The Canberra Bomber - Memories of a Pilot - Bill Kilsby

 

       THE CANBERRA BOMBER

                         MEMORIES OF A PILOT

       Wing Commander C.G. (Bill) Kilsby MBE AFC

 

                                                                  INTRODUCTION

 

General

 

            During WW2, the major RAAF heavy bomber aircraft was the Liberator which had been used extensively in the Pacific Campaign.  But after the war, the government intended to preserve the Australian aviation industry which was mainly attuned to British aircraft.   Consequently, Liberators were scrapped and the resurgent RAAF force was slowly equipped with Lincolns built by the Government Aircraft Factory at Fisherman’s Bend, Victoria.  

 

             The major operational role undertaken by the Lincolns was by No 1 Sqn during the Malayan Emergency from 1951 to 1958.  An amazing number of sorties were flown and an enormous tonnage of bombs were dropped in that campaign.  Actually, the Liberators could have fulfilled the role with a lot more comfort for the crews and it would have avoided sending a large number of aircrew deaf.   And by 1951, the Government decided to re-equip the bomber force with the British General Electric B2 version of the Canberra to be made by the Government Aircraft Factory (its designation was the B20 and its RAAF prefix was A84 -).   Also, the Rolls Royce Avon jet engine would be made under licence by Commonwealth Aircraft Corporation also at Fishermans Bend as they had previously produced the Rolls Royce Merlin for Lincolns and Mustangs.

 

            An aside.  I mention the Government Aircraft Factory Melbourne a number of times.  Lincolns, and some basic Canberra parts were made at the factory at Fishermans’ Bend.  There was a limited airfield there and all associated Lincoln flights were conducted there.  After returning to Melbourne to live in 1997, I have looked many times from the height of the Westgate Bridge to see if I can identify where the airfield was but it has completely disappeared.  Canberra final assembly and all associated flights were conducted from the then new airfield at Avalon.

 

            Although the Canberra force was to consist of Australian built aircraft the first of which was to come off the factory line in early 1953, it was decided to obtain a couple of early models for pre experience.  Thus, the Canberra was introduced to Australia by the arrival of English Electric pre production model A84-307 ferried by Wg Cdr Jel Cummings (Commanding Officer of Aircraft Research and Development Unit) and Sqn Ldr Col Harvey late in 1951.  It was temporarily assigned to ARDU at Laverton for a limited test program.  A little later it was joined at Laverton by early British production model, A84-125.  

 

Initial Developments.

 

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            Looking forward to introducing the aircraft into No. 82 Bomber Wing at Amberley Queensland, the Canberra Conversion Flight was formed at Amberley with the two aircraft in early 1952. Two pilots and two navigators were trained on them to become the command and staff of the unit.   The pilots were Sqn Ldr Jim Wilson (Commanding Officer) and Flg Off Bob Atkinson while the navigators were Flt Lt McLeod and Flt Lt Geoff Blackwell.

            Also, in early 1952 a requirement arose for two RAAF Canberra crews to participate in a joint RAF, RAAF weapons trial program at Woomera.   I had just returned from a full tour of operations as an Lincoln captain in the Malayan Emergency and was selected as captain of one of the crews, my navigator was Flg Off Eric Walker.  The other pilot was Flt Sgt Ron Hunt who had just completed a tour on Meteors in Korea.  His navigator was Flt Sgt John Bell.

 

            The Liberator had a crew of 11 men; the Lincoln 7 men.  The Canberra crew was normally 2: pilot and navigator.  A good crew could integrate and form a great team.  Over time, I crewed with many navigators and found every one of them excellent - it was the ideal crew for highspeed operations.

 

            In all my time in the RAAF, the aircrews and ground crews were highly skilled and dedicated to the Air Force.  I guess that all the aircrew were a bit mad and obsessed with aircraft, flying, and the mission.  In the squadron hut, in the mess after work, at squadron outings, everywhere, we discussed flying and operations.  Over a few, or many beers, more imaginative solutions were aired and some of them were worthy of follow up.

 

Evolution of the Canberra Aircraft in Australia.

 

            The two British aircraft were markedly different from each other and from the Australian version when it was eventually produced.   A84-307 had disk brakes but was not fitted with the Dunlop Maxaret system which was the earliest version of ABS, but that system was fitted to A84-125 and to all Australian produced Canberras.  Both aircraft had 12 channel VHF communications only but the associated microphone wiring and intercommunication system was different. 307's was quite rational but 125 was fitted with a system designed for a maritime aircraft with a crew of 10 plus and a complex array of radios etc.  No one ever understood it and it was the cause of a couple of unusual outcomes.

 

            The Australian produced Canberra was a reproduction of the British B2 and almost identical being fitted with Rolls Royce Avon RA3 engines of 7,000 lbs. thrust.   They were very inflexible and very difficult to handle.   From about A84-214 on the newer RA7 (the same as in the Sabre) engines were fitted to add 500 lbs of thrust and much more flexible handling but still within the limitations of a single spool configuration.

 

Pilot Conversion to Type.

 

            There was no dual aircraft until the late 1950's when the two original British built aircraft were so modified.  The method of pilot conversion was for the pupil to sit on the jump seat and observe for two flights.  Then the instructor sat on the jump seat in an advisory role for the next flight -  not a happy instructor!  That was also made more difficult as touch and go landings were prohibited because of the poor engine characteristics.  Also, repeat landings on any flight were prohibited due to lack of brake cooling.

 

            Our conversion was prolonged because of limited aircraft serviceability mainly due to a lack of spares.  Nevertheless, both crews were deemed converted in late July.   During the down periods of the aircraft, I had continued as the 82 Wing instructor on Lincolns.  Simultaneously, the Conversion Flight was conducting ground crew training on the aircraft and I was able to sit in on their lectures and thus gained a very thorough knowledge of the aircraft and was fully involved during that time.   On completion of the course, I was accredited as an instructor on Canberras.

 

Handling.

 

            The Canberra was a pretty aircraft, the first bomber to have elegant lines.   The airframe itself was easy and a delight to fly.  It had no auto pilot which meant hand flying it all the time.  I found that no sweat except when looking up radio or navigation frequencies or complex let down procedures especially at night due to the abysmal cockpit lighting which was inherent in British aircraft.  Further, it freed us from the jerky, wallowing action of the British auto pilots thus improving fuel consumption on a well flown aircraft.  It was a new dimension for most of us, ushering in the vastly different characteristics of jet aircraft.  The cord of the wing was large providing a large wing area for the wing span (low aspect ratio) providing for a low landing speed (105 knots) and reasonable high max speed but a very bumpy ride in any turbulence.  As well as different handling, we the plodding bomber crews were lifted in speed from about 200 knots cruising speed to 500 + knots and introduced to the problems with very high altitude and high Mach numbers.  The climb speed was 300k IAS, twice that of the Lincoln. The Canberra was limited to Mach .85 with marked buffet and pitching from M.82 up. 

 

            The Canberra did not have power controls but it had to contend with a vast range of speeds and the large pitch variations as Mach changes caused large movements of the center of pressure.  To that end, a fully moving tailplane was installed for the forward 2/3 of the aerofoil.  That was operated by an electric screw jack controlled by a three way switch (up, down, or center, off) on the top of the right hand control yolk.  Normal movements were small and it was usually operated by a flicking motion and that also served as the elevator trim.  The trailing part of the tailplane was a fairly conventional elevator but with a quite intricate method of operation.   The details of the control system is shown in ANNEX B

 

 

Comfort.

 

            There was none.   Although the aircraft was quite capable of altitudes of up to 55,000 feet, the maximum altitude was decreed to be 48,000 feet because of crew limitations coping with the very high cabin altitude as the Canberra was only pressurized to a maximum of 3 ½ lbs/ sq. inch (American and later British combat aircraft were pressurized. to 8 PSI).  Both heating and cooling of the cabin was abysmal in early aircraft with the result that in the tropics, cabin temperature before takeoff would be as high as 70 c.  Less than 20 minutes later, on reaching cruising altitude of 40,000 feet, the cabin temperature would be about - 5 c.  All the metal interior would be frosted over.  In fact, it was like sitting in a deep freeze.  At the same time, the cabin altitude would be about 28,000 feet necessitating the crew to breath 100% oxygen delivered under some pressure. We wore a new type oxygen masks which when coupled to a pressure vest allowed breathing high pressure oxygen in cases of very low cabin pressure.  These masks were absolutely rigid and after a while hurt like hell especially across the nose sometimes rubbing it raw.  I still carry the scars.

 

            There was no way to dress for such extremes and the 4 hours plus cruise became extremely uncomfortable to say the least.  The air conditioning system was modified in production aircraft from about mid1954 and, ultimately, previous aircraft were post modified.  Later military aircraft types were pressurized to 8 lbs/sq. inch, but the Canberra could not be as the airframe would not have stood the extra pressure differential .

            The distance from floor to the eggshell canopy was limited in the pilot’s area.  Thus, for escape, the ejection seat had to accelerate the pilot over a shorter distance than the seats were originally designed.    That resulted in a high G force (18G) close to the extreme that the body could stand without injury.  For that reason, the only cushion provided for the pilot and navigator was the survival water bladder and a 10 millimeter felt pad.  The occupants’ tails became sore very quickly.

 

 

            The rapid decompression of the cabin on climb and the reverse compression during descent posed more than comfort problems.   We ensured that crews did not fly with a head cold.  Even then there were problems with extreme ear pain if there were any restriction in the ear canals.  But a more serious incident occurred on a flight 1^st February 1962.  I took off from Amberley with Flt Lt Slim Sawyer as Navigator on a high level air defense exercise in the Sydney area.  Just as we leveled at 40,000 feet, Slim gasped and then croaked something like “I think that one of my lungs has burst”!  I closed the throttles and did an almost wing over into a steep descent with full speed brakes out.  I informed Brisbane control of an emergency, got clearance for descent and to change radio frequency to Amberley.  I declared an emergency to them, requested a straight in approach and that an ambulance meet us.   The aircraft was fitted with tip tanks (empty) for which there was a descent limitation of 5,000 feet / minute as there were no inward venting valves on the tip tanks.  We exceeded that for the first 15,000 feet or so, but then heeded the warning at lower altitudes where ambient pressure was increasing rapidly.   Slim was conscious, but in considerable pain.

 

            We maintained maximum permitted speed until it was necessary to get the aircraft configured for landing.   We did not get down to correct approach speed until about 500 feet on finals.  After touch down hard brake and then engine shut down to coast to an intercepting taxiway where the ambulance had stationed.   The medics helped Slim from the aircraft and he was in hospital about 20 minutes from the start of the incident.  I believe one of Slim’s lungs had deflated.  However, he made a full recovery and was assessed fit for flying about 6 months later but I do not think for Canberras.  Certainly, I have no record of him flying with me again. 

 

Engines.

 

             Previous jets, Vampires and Meteors, were powered by engines with centrifugal compressors.  The Canberra was the first jet aircraft in Australia with axial flow engines, namely the Rolls Royce Avon RA3.    In axial flow engines the air is ingested , compressed, burned, and exhausted in a continuos direction instead of  by the centrifugal compressor in earlier engines.    It produced infinitely more power but was, in the early versions, very difficult to operate. 

 

            This may be a good place to mention the aircraft’s single engine flight characteristics.  From a 45,000 foot cruise while lightly laden, without any power at all, the aircraft would glide for 150 + nautical miles (270 km.) if the optimum speed was maintained.  Thus, with one engine operating at maximum continuous, the float down was very long.  What is more, the aircraft would maintain altitude on one engine at about 25,000 feet but the fuel consumption was very high.  Approach and landing was not difficult provided the correct procedures were followed.   The critical speed was decreed as 120 knots (that is the minimum speed that the pilot could hold directional control with one only engine operating at full power) but most of us found that quite a bit optimistic.  A go round could be performed if commenced early.    Therefore, one maintained 120 knots + and at least 5,000 RPM on the good engine until committed to land.  As flaps were only 2 position (up or fully down) flaps were not extended until commitment and then speed was brought back to normal.

            For single engine flight, the rudder was extremely heavy when significant power was applied.  I used to try and lock the active knee, pull the harness as tight as possible so that I would not be lifted up in the seat and juggle the throttle for as much power as I could hold while maintaining directional control.

 

            During conversion, the difficult engine characteristics led to two incidents.   Descent from cruising altitude was with engines at idle and speed brakes out in order to minimise the time spent with the engines inefficient and gulping fuel.   On re-entering the circuit after descent from altitude, power was brought up to 6500 - 7000rpm approx.    The first incident was with Ron Hunt when he failed to recognize the engine rumbling which indicated a compressor stall on one engine as he tried to accelerate the engines from idle.   Subsequently, the engine was cooked and had to be changed.  A couple of days later, I encountered the same problem on the port engine of the other aircraft (A84-307) but luckily, and probably alerted by Ron’s incident, I understood what was happening.  Over several very careful attempts, the engine refused to accelerate above 6000 RPM.  I then shut it down and did a single engine landing which was not without additional dramas.

 

            In those days, the main runway at Amberley (6,000 feet long) was crossed by the New England Highway about 2,000 feet from the threshold.  Traffic control was maintained by the use of manually operated boom gates which covered about 70 % of the highway in the active direction.  When I was approaching to land, the guards closed the boom gates on each side of the runway but then transferred their interest to the approaching aircraft which was still a novelty.   Along came an old utility and chugged around the barrier and out onto the strip.  As I was already in flare, the only thing I could do was to push up as much power as I could control on the operating engine and just managed to go over the ute before sagging back onto the runway.  Then it was hard brake as a good bit of the strip was already behind me.

 

            The engine was ground run and it repeatedly compressor stalled at 5,900 RPM much to the bewilderment of our ground staff.   They had little test equipment to fully explore the problem.   Why two similar malfunctions should occur so close together was never worked out and we had few similar incidents subsequently.  The engine was eventually removed and sent back to Commonwealth Aircraft Factory where they discovered a faulty bleed valve unit.   All the automatic functions for the engine were replaced and it again functioned normally and was returned to service.   Those engines did not have a shrouded rear turbine and thus were limited to a 150 hour operating life.  It was not long before the engine was reinstalled, this time on the starboard side of A84-307.  About a year later I was flying that aircraft out of Laverton.   At 40,000 feet north of Sale there was an horrendous clatter.  Can you imagine a metal garbage can being struck with a sledge hammer at a rate of 7,000 times per minute.  After making a very improper exclamation, I identified the problem which was the unshrouded turbine coming apart, shut down the engine, reduced speed to minimum to try and stop the damaged turbine from destroying the outer casing of the engine, and commenced a very slow let down back to Laverton.  The noise was considerably abated and there was no trouble with a single engine landing quite some time later.

 

            Later engines were fitted with shrouded turbines and this problem did not re occur.  Also, the RA3 engine was modified to incorporate progressively opening swirl vanes (the first stage of compressor) instead of the original two position devices and thus improve the engine handling characteristics.  From about production aircraft A84-211 onward, all aircraft were fitted with the later RA7 engine which was more powerful and user friendly.  But, still fairly tricky.

            Another more serious incident.   In preparation for the 1953 air race from London to Christchurch, Mike Ridgeway, with Jack Bell as navigator and, I think Phil Hamilton Foster were doing a quick check out of the refueling and flight planning facilities on the sectors from Ceylon back to Woomera..    While flying at 45,000 feet about midway between Ceylon and Cocos Island, they encountered a line of storms going up to well above 48,000 feet.  Mike tried to climb through a gap and at 48,000 feet he suddenly had both engines flame out.   Of course, no attempt could be made to relight them above 15,000 feet.   Somehow, they managed to penetrate the storms while gliding.  All possible electrical equipment was turned off to conserve battery power as the generators were not working with the engines shut down.  It was a long, quiet and very bumpy ride.  I believe that Mike turned on the VHF a couple of times to transmit a “MAYDAY” but as the VHF only had a range of about 200 miles, no one heard.   On reaching 15,000 feet, Mike tried a relight on one engine.   No success!  Then the other.  No success!   A very worrying time.   At last, at a frighteningly lower altitude, one engine was successfully restarted.   Very soon after, surprisingly, the other also lit.   The rest of the flight to Cocos Island was apparently without further incident.   I later asked Jack Bell what he was doing during the long, long descent.  He said “I packed up my nav bag and tidied up the nav station.  What else was there to do?”

 

            A possible explanation of the reluctance of the engines to relight was through low battery voltage.  Certainly, the second engine started without trouble once the first generator was on line.   The cause of the double engine flame out was a lot more complex.

 

            After the relight, both engines functioned normally; the ground staff could find nothing wrong with them.   Mike then cautiously flew the aircraft back to Laverton.  Rolls Royce assistance was requested and then it was disclosed that they were aware of a high altitude, high RPM compressor instability.   The problem would only occur at temperatures which, at that time were considered far below any that could occur.  That was because of a lack of knowledge of high altitude atmospheric conditions in the tropics.  When the flame outs occurred, the ambient temperature was probably about -65c at their altitude (10 c. below ICAN  figures) and the IAS (Indicated Air Speed) was low resulting in very little ram effect in the engine intakes.  The ensuing compressor instability caused the multiple flame out.

 

            The problem was inherent in the engine type so, for the future we were aware that a problem could occur with a combination of low IAS and extremely low temperatures at high altitude and thus we tried to avoid the danger area.  There was a formula for calculating it but it was impractical for use in most circumstances.  Thankfully, the conditions were extremely unlikely to occur but, some engines were more susceptible than others and turbulence exaggerated the problem.   While engaged in a test program at Woomera, on two occasions, I had the port engine flame out through this phenomenon while a little outside the danger zone.   On both occasions, the starboard engine was not affected. 

 

            Although various modifications were made over the life of the Avon engine to improve its power and engine handling, it still had the basic deficiencies inherent to a single spool engine - that is that all stages of compressor and turbines were on one shaft thus ensuring that the compromises were too great.  Second generation axial flow jet engines were designed first with two spools (first stages of compressor and final stages of turbine being on an inner shaft with later stages of compressor and first stages of turbine on an outer shaft each tuned for efficiency) and now a days, with more spools and leading fan stages of compressor.

            Our conversion suffered a number of stoppages through aircraft grounding the first of which  was because of the escape system which depended on a number of explosive bolts (see Annex B for a description of the escape system.).   Also, the ejection seats were also powered by explosive shells. The bolts had a very short installed life.   Of course no replacements were available and the aircraft were grounded until they arrived.  The next hold up was also because of the escape system - this time because of failure of the rear hinge of the canopy.   This was redesigned and we got on with it again. 

 

            All the escape system explosive bolts were isolated by a Master Switch on the left console.   Subsequently, the canopy and the navigators hatch could be detonated by separate switches for pilot and navigator and a further switch on the left console was to sever the elevator control.   The activation switches were covered by a hinged flap with a hole for the switch to poke through when off and the flap was lightly lock wired down.  During pre start up checks, the drill was to check those switches lock wired off and the master switch off.  Then, immediately before takeoff, the pilot would turn on the master switch.

 

            In 1960 I fell foul of a gross deficiency in the system.  I was air testing one of the dual aircraft which had the canopy detonation switch on the starboard side of the instrument panel.  Before start up, I reached over and checked the safety flap in position and lock wired.  Then, immediately before takeoff, I turned on the master switch.   There was a hell of an explosion as the canopy explosive bolts fired.  I got bruised a bit by flying bolt heads and the cabin was full of smoke.   After shutting down, I checked the activator switch which still had the flap down and lock wired.  But to my surprise, I found that the flap had two holes in it and had been wrongly lock wired in the “ON”  position during inspection.   The canopy was busted in the incident.  To make matters worse, there was much discussion about it in the hanger and one of the senior armourers, while trying to explain what had happened to one of his men, managed to blow the navigators hatch in another aircraft in the hanger.   I put in a defect report on the safety flap as I believed that it was inconceivable that a safety flap could be used which could permit the switch to be safetied in the wrong position.   That did not stop the Station Commander from insisting that I be charged for “negligently damaging Her Majesty’s aircraft” and he took pleasure in awarding me a reprimand which is shown in one’s documents and specifies a delay in promotion.  I was not pleased and considered it very unjust.  Also, I was disgusted at the complete idiocy in that the flap was not ever modified.      

 

            Many pilots throughout the world had very grave doubts about all the switches and detonators in the escape system.   Consequently, they activated it only at times they considered of higher risk: for example landing.  Such actions are probably the explanation of the following major accident..

 

            These are the known facts.   A RAF Canberra was approaching its home airfield.   The pilot established contact with the control tower and then there was silence.     The aircraft dived into the ground at a steep angle some miles from the airfield.    The remains of the pilot’s canopy were located reasonably intact some many miles further back along the aircraft’s flight path.   The remainder of the aircraft was very badly broken up but it appeared that the tailplane was in the full nose down position The cockpit was completely disintegrated and the human remains very greatly scrambled, scattered and buried.  The remains of the two navigators were found in a farmer’s field along the way.    Owing to lack of witnesses and the extreme destruction of the aircraft, no firm conclusions could be established.    But knowledge of the aircraft type and its deficiencies brought forward this version of the sequence of the events.

 

            The pilot did not turn on the detonation master switch until approaching the airfield for landing.   But the activate switch was live and the pilot’s canopy blew.    The rear hinge failed and the forward edge of the canopy decapitated the pilot.    The aircraft was well trimmed and continued to fly smoothly.    The two navigators came forward.    One of them was a scrubbed pilot before being assigned to navigator training.   They thought that he could land the aircraft if he could get into the seat.    They tried to extricate the pilot but, on release of his safety harness, he sagged across the control column thus activating the tailplane switch causing the aircraft to very rapidly pitch nose down throwing both navigators out through the missing canopy.   The aircraft dived into the ground at high speed.

 

Fuel Handling.

 

             Of the fuselage tanks, the front and rear carried the bulk of the fuel.  The gauges were arranged in a column towards the starboard side of the instrument panel.  On each side of the gauge for each tank was the engine fuel supply switch, the left one being for the port engine and the right for the starboard.  For take off and landing, all switches were on.  For cruise, we fed one engine with the front tank and the other with the rear to maintain balance and to make sure that the center smaller tank with less surge was available for landing.  Thus, at top of climb, both pumps for the center tank would be switched off and one each for the front and rear tank.  The initial configuration could well be: left front tank switch on, right front off, both center off, right rear on, left rear off.   To even out the wear on the pumps, the pattern would be changed every half hour in a sequence like: left rear on, left front off, right front on, right rear off.  We very quickly got confident and could do the change very quickly without any thought.  The trick was to make sure that the other pump and cock for each engine was switched on before the previously active one was switched off.  Of course, it was inevitable, that some distraction would cause two pumps to be on for one engine and none for the other - immediately, one engine out!

 

            One night early on, I was flying A84-125 on a Navigation exercise with two navigators in the back.  At 40,000 over outback NSW, I got the fuel pump sequence wrong causing a flame out for the port engine.   I went through the engine shut down procedures and commenced let down to 15,000 feet, the maximum altitude that those early engines could be relit.  Simultaneously, my headset microphone went off line so I could not tell the navigators about it.  Naturally, they became a bit agitated and started to demand an explanation as to what was going on.  In the absence of being able to talk, I tried to make appropriate calming hand signals hoping they would be discernable in the back in the almost dark.  That did not work very well and the lead navigator shouted on the intercom “Don’t keep wagging your hand at me, tell us what’s happening”!   Eventually, I thought of the mysterious switch and found that I must have knocked it on during the flurry of closing throttle and high pressure cock to complete the shut down of the engine.  After it was turned off, we reestablished  communication.  We descended to 15,000 feet and set up the complex procedure to successfully relight the engine, and got on with the navex.  Later, in the Mess over a couple of beers, the lead navigator said “I had decided that at 10,000 feet, I would blow the hatch and eject”.  “Sorry, you could not do that” said the second navigator.  “Why?”.  “I was going to go at 15,000 feet!”

 

             Thus, we learned the purpose of the extra switch.  It was so that the pilot could isolate his microphone from the intercom when he was involved in using the radios.  Maybe useful on a multi crewed maritime aircraft, but completely superfluous in the Canberra.

 

Nose Wheel Up.

 

            During the London to Christchurch Air Race in August 1953, our first nose wheel up accident occurred.    A84-201 was landing at Woomera very late at night having departed that leg from Colombo in Ceylon.  The crew were Sqn Ldr Peter Raw (Captain), Flt Lt Noel Davis (Co - pilot), and Flt Lt Bill Kerr as Navigator.  Noel was flying the aircraft while Peter was doing all the support tasks such as assisting in the navigation and keeping the fuel log.  All the crew were fatigued having had no rest since leaving England - each refueling stop was only a few minutes while fuel was taken aboard and a new flight plan delivered for the next leg.  At Woomera, Noel did not realize that the nosewheel did not extend and landed with it up causing quite considerable damage to the underside of the nose of the aircraft.  Some of the aerials were damaged and the pitot head was ripped off.   The engineering staff did a wonderful job to get the nose wheel extended, make superficial repairs to the skin of the aircraft, and reattach the pitot head which, of course could not be calibrated, and thus their air speed indication would be not accurate.  The crew then carried on to Christchurch where the weather was far from good.   Owing to the then lack of radio aids, they had to do a complicated let down procedure thus losing more time.  Despite all that, they managed second place. 

 

            Subsequent enquiries did not reveal the cause of the nose wheel lock up.  That the pilot did not realize that the wheel was still locked up was forgiven due to his fatigue and the configuration of the undercarriage indicator lights.  The indicators show a green light for every wheel down and locked and a red light for every wheel in an unlocked state.  There are no lights shown for wheels locked up.  To stop the green lights interfering with pilot vision when landing, there is a dimming system for use at night which renders them to a dull glow.  After selecting gear down, Noel saw the dim glow of greens and failed to notice that there were only two - there was no red light for the nose wheel as it remained locked up.

 

            Subsequently, we, the pilots realized the problem and modified our check from “Gear down - green lights” to “Gear down - 1, 2, 3 greens” counting them off.  That was perfectly adequate pending a possible modification that would show a red light on every wheel that was not locked down after gear was selected.   That approach was not pursued.  Instead our brains trust installed a bright flashing amber light that activated when the throttles were retarded and all gear was not locked down.   There was no dimmer for night operations.  It was hopeless.  We usually started let down from forty or so thousand feet with the throttles closed and continued instrument procedures until touch down.  Gear was not selected until 1,500 feet turning on to final.   During all that time, at night the pilot was blinded with that damned flashing light which, when combined with the appalling instrument lighting, caused a dangerous situation.  However, our defect reports and pleas went nowhere.  On a number of occasions, I solved the problem by giving the light a good kick again causing threats of wilfully damaging.

 

            Of all the gear failures in the Canberra, nose wheel failure to extend was the most common.   I had the same problem occur at Darwin, as that which had occurred on the air race, and was able to work out the reason.  On return to base at Darwin after a high level navex, the nose gear on A84-211 failed to extend.  Coincidentally, that aircraft also had a problem with asymmetric feed of the tip tanks and on this occasion the starboard tip tank also had failed to feed.   Suspecting the problem, I retracted the main gear and proceeded to fly around at fairly high speed.  Almost immediately, the tip tank started to feed as the fuel temperature increased.   About 10 minutes later, recycling the gear produced three greens - all three wheels down and locked.    Obviously, the ice on the up lock had melted.

 

            The problem occurred after taking off  in a very moist atmosphere and quickly climbing to the very low temperatures that can be experienced in the tropics.   The moist air condenses and settles on the operating lever of the nose wheel lock forming clear ice which is very hard and strong.  The unlocking mechanism is then un able to break the lock clear.  That problem occurred to me three times, always with A84-211.   No other aircraft, including A84-201, was so affected to my knowledge.  I have no idea why it only occurred to that one aircraft but can only conclude that it was a quirk of the ventilation in the nose wheel bay on that particular aircraft.  The explanation for it only occurring once for A84-201 could have been that the aircraft had become cold soaked in its long journey from the United Kingdom and, after the very quick turn around it was conducive to icing.

 

            There were other cases of nose wheel up landings but it is fairly unlikely that they were caused by the above problem.   One that comes to mind was an incident when one of our aircraft was landing at Richmond.   The pilot was Flg Off Keith (Masher) Molloy who was brilliant.  When Masher realised the nose wheel was not going to extend (he had recycled the gear three times, the maximum permitted) he planned his landing.  He still had a lot of fuel.  He organized the control tower personnel to get the weight and balance tables and read certain sections to him.  He then calculated, in his head, that if he could burn off all the fuel in the forward fuselage tank and retain most of it in the rear tank, the Center of Gravity would move aft sufficient for it to be just behind the main wheels with the nose in a very high attitude.  He then asked that a number of ground staff assemble near the end of the runway.   When he got the balance to where he wanted (it was at maximum aft limit) he landed pulling the nose high and getting some braking while the tailplane was still effective. As speed died, he shut down the engines and rotated the nose higher until the emergency tail skid was dragging.  When the aircraft was slow enough, the ground staff rushed out and held the tail down until a support could be placed under the nose.   Result was no damage except some rubbing to the tail skid which had to be replaced.

 

            Another instance in which I recall was to one of my junior pilots at Amberley.   I was invited to the tower to advise when he could not get the nose wheel to extend.   He did not have the fuel available to get the Center of Gravity as far aft as Masher had.  However, we conferred and he proceeded to set it up as best available.  We also got the ground staff positioned.   Unfortunately, after touch down,  he could not get much brake without tipping the aircraft on its nose.  Subsequently, the aircraft overran the runway and the extra drag to the wheels on the unprepared surface caused the nose to gently pitch down.  There was a bit of damage to under the nose but not that much.  The young pilot did and excellent job.

 

 

                                                       OPERATING THE AIRCRAFT

 

Weather.

 

            We very soon found out that tropical and southern hemisphere mid latitudes weather was vastly different to that of Europe and that very little was really known about it.  Everyone had believed for years that the criteria laid out in the International Convention of Air Navigation (ICAN) was gospel.   But we discovered that was not so and that ICAN was really only an average of the vastly different circumstances occurring across the globe.

            ICAN states that the temperature will decrease at a linear rate from ground level up to the tropopause which is the level above which temperature no longer decreases with increasing altitude and in some cases increases.  ICAN decrees that the tropopause will occur at 35,000 feet and the temperature will be - 54.7 c.  In fact, when progressing from the poles to the equator, the height of the tropopause could be about 20,000 feet and the temperature     -35 c. at the poles and, for the equator, 45,000 feet and -65 c.   Because of that we experienced a vastly different environment.  Also, that was a major contributor to the “jet stream”.   The jet stream was completely new to us but it was to affect most aspects of high altitude flight.   

 

            The jet stream is a band of very high speed wind at high altitude.   It is centered about the tropopause and probably causes a mutation of the tropopause which I will call the split tropopause.  It runs in streams and after a while we got to know where to expect a jet stream although they changed location over the year and for some periods were non existent.  An active jet stream could produce winds of 180 knots or so.   In Australia, we found that there was such a jet stream curving down from about Exmouth Gulf across central West Australia and then North East to exit Australia somewhere near Evans Head.  That stream moves about a bit and is at its strongest in the winter and quite moderate or non existent in the summer.   Thus, the airlines take almost an hour longer on the flight from Sydney, Melbourne, or Adelaide to Bali than the return during the winter. 

 

            Previous thinking was that thunderstorm clouds would not penetrate far above the tropopause and thus, according to ICAN, would not be evident above 35,000 feet.   But in real life we found thunder heads rising to well above 55,000 feet in the tropics.  Because of the extent of the associated rise of the air, the updrafts were tremendous.   Also, there is a large difference in the cooling of dry air to that of moist air which resulted in extreme turbulence in thunderstorms.  During tropical trials of the Canberra at Darwin in 1954, we recounted our observations to the meteorological staff and were mainly disbelieved.   One meteorologist was so adamant that I challenged him to fly with me and made all the arrangements.  At 45,000 feet he was astounded to see thunder heads rising at least another 10,000 feet above us.  He changed his ideas and from then on was a great help in understanding the new knowledge that was unfolding.  

 

Navigation.

 

            The Canberra was designed for British operations: that is short range and with the “G” navigational and bombing systems used quite effectively in Europe during the latter stages of WW2.   But Australia did not have the ground based system to allow that to operate.  Instead, the only navigational aid was a dubious British radio compass which provided little help especially at night.   There were very few radio beacons and in the outback, even commercial radio stations were infrequent.  However, we sure learned the words of ‘beautiful, beautiful Queensland” which seemed to be about the only music played by outback radio stations.  Also, because our operations demanded much greater range, we intended to operate at much higher altitudes which involved so many of the previously unknowns.       

 

              Also, the early aircraft did not have leading edge fuel tanks and thus, carried 1000 gallons less of fuel than the later models were capable of.  Thus, fuel was critical and we based a lot of importance on flight planning which was even more difficult because the meteorologists had little data on which to base their weather forecasts. During flight planning, the navigator would use the Dalton Navigational calculator to compute a comprehensive air plot with headings and ground speeds.    The pilot would use a trig system to calculate head and tail wind components and thus the time on each leg.  Using the fuel consumption tables, 

he would then construct a fuel graph for the flight.  Pilot and navigator would then compare their time over each leg.  If there were a discrepancy of more than a minute on any leg, both crew would recalculate all.

 

             In flight, we used to check the wind whenever possible by a system of three course winds.   It was done by taking a drift (using the bombsight) on the main heading, then turning 60 degrees and hold it for 2 minutes while taking another drift, then turning back 120 degrees the other way, again holding it for 2 minutes while taking another drift, then back to original heading.   The process was deemed to merely place the aircraft 2 minutes less along the air plot and the three drifts would allow the navigator to calculate the wind speed and direction.   But we had to be able to see the surface which was not possible at night or above cloud.   It was extremely difficult to cope with jet streams which were a completely unknown quantity.   We slowly got to build a picture of where to expect them in our operating area.  Very high winds were common in the Evans Head area.   Another area was south of the Gulf of Carpenteria where 100 knot winds often occurred with direction anywhere from North East to North West.

 

             But I got a nasty surprise one night in August 1954 when flying a Navex Perth, Carnarvon, Kalgoorlie, Perth at 35,000 feet.  We were quite a bit late on ETA at Carnarvon.   Then, on the leg down to Kalgoorlie there was nothing to check our navigation.  No small towns, no radio beacons, nothing.   Before ETA was up, I saw a few scattered lights where no lights should have been.   Luckily, we presumed that it could only be Forrest which was far East of where we should have been.   We turned West to head back to Perth.   After sometime we managed to get a fix and confirm that we were bucking a very strong wind and had a long way to go.   No airfields to the East of Perth were open and we were critical on fuel.   Luckily, we decided to descend 5,000 feet and encountered a much lesser headwind.  The radio compass eventually came good on the beacon at Pearce and we were able to land there with very little fuel left.  

 

            On the ground, we back plotted the flight using the all the information that was then available and established that we had encountered a 180 knot jet stream.   I learned a lot about jet streams that night.  Mainly the characteristic ripple turbulence on entering or at the edge of a jet stream is an excellent pointer to its existence.  It is caused by the friction of very fast air against slow air on the outer - very much like the ripples near a river bank.   Those ripples can be a guide if one tries to climb above or descend below from the very high speed core which may only cover 5,000 feet or so around the tropopause.

 

            Later on we got Distance Measuring Equipment which indicated the distance to a series of beacons mainly situated at RAAF airfields (not to be confused with TACAN which also gave a very accurate direction indication).   Later still we got Green Satin, a doppler system which accurately gave drift and ground speed.   Sheer bliss.

 

Fatal Accidents.

 

            Military aircraft are built for war purposes and therefore do not prescribe to the safety standards of civilian aircraft.   Also, military assault aircraft are not intended for continual day to day operations over a long period.; they are not designed for big flying hour totals.  Thus, military aircraft are loaded beyond the limits of civil acceptance and are operated to their very limits during training and action.  Not to do so could well result in military inferiority and disaster.  In this context, the Canberra was a very safe aircraft.   To my recall, there were only three fatal accidents in the long operating life of the Canberra, with, I think, only six killed.   Compared with the first few years of the Lincoln, that was not much.

 

            The first was a conversion accident at Amberley.  Flt Lt David Nichols was the trainee pilot at the controls with my very good friend Flt Lt Noel Davis as the instructor pilot - remember that he did not have access to any controls but could only act in an advisory capacity.   I cannot remember who the navigator was nor do I remember what was the result of the Court of Inquiry.  However, my impression is that they were performing a single engine go around and it got out of control resulting in a viscous peel off before striking the ground in the middle of the airfield where the aircraft burned.  All were killed!  One theory was that they induced rudder stall after which the aircraft would be completely uncontrollable.  Tests at altitude could replicate the final manoeuver.   Maybe? 

 

            A side story.  Molly and I were living in one of the Ipswich suburbs.  A neighbor came to her and said that he had been driving past Amberley and saw a Canberra crash and burn: was it Bill?   Molly had heard nothing and statistically there was a good chance that it could be me as there were so few that could fly the airplane.   Luckily, she knew that I was ferrying a Long Nose Lincoln to Government Aircraft Factory in Melbourne that day and bringing back another the next day ( my secondary duty was still as 82 Wing Lincoln instructor and I was also testing any darn aircraft that I could get my hands on at 82 Wing or No. 3 Aircraft Depot).   Otherwise, she could have had a real worry.   I think that Des could have cut his tongue out immediately after he said it .

 

            Early in March 1955, a Canberra on a training flight out of Amberley, had the navigator eject at low level.   His ejection seat and parachute did not have time to complete their sequences due to the extremely low altitude and he was killed.  The navigator was Flg Off Martin, a RAF exchange officer.   Once again, I think that the Court of Inquiry failed to establish the cause of the accident.

 

            There were many theories how it happened.   The most likely is that, at high altitude, the pilot (still quite inexperienced on type) performed a wing over into a steep dive to enter a Mach run.   That was not an accepted method of entry.  The aircraft accelerated rapidly and entered high Mach buffet with its associated pitch up, pitch down.   Because of the high dive angle, the aircraft would not respond properly to controls and would only alternate in pitch up and pitch down around the main dive angle.  At a much lower altitude, the very high airspeed resulted in sufficient drag to reduce the Mach no and  then restore flight control.   In his efforts to bring the nose up, the pilot would have wound the tailplane very nose up and that suddenly became effective.   A violent pull out eventuated only just clearing the ground, during which the navigator ejected.

 

            Examination by the engineering staff established that the aircraft (A84-204) had been violently over stressed and its repair was beyond the capabilities at Amberley.  Also, they could not fit a new navigators hatch there.  It was arranged that the aircraft would be returned to the factory at Avalon for complete examination and repair.   I and my navigator, Flt Lt Geoff Hughes, were selected for the job of getting it there.   It came back some years later as a trainer.

 

            First we did an air test - up to 10,000 feet and maintaining low airspeeds to minimise stresses.   The missing ejector seat had not been replaced so the navigator’s position was untenable.   Geoff tried the starboard navigator’s ejection seat but turbulence was too great for him to be effective.  Thus, he came forward to the jump seat beside me with the option of scrambling back to the ejector seat if needs be.   It was also extremely cold throughout the cockpit.

 

            The air test went OK and we planned our delivery flight.   Because of transit at 10,000 feet, the slow airspeed, and drag caused by the missing hatch, fuel consumption would be horrific.  Therefore, we planned an intermediate stop to refuel at Williamtown Air Base in NSW.

 

            Once again, the flight went OK and we treated that aircraft very gently.   It sure raised a lot of interest at Williamtown and at Government Aircraft Factory, Avalon.   We returned the next day to Amberley by delivering a new aircraft to the squadron - a much more pleasant flight.   

 

            The other fatal accident that I recall was also at Amberley in either late 1965 or early 1966.  I had long left the Canberra program at that time.  It was also a training single engine approach.   Both the pilot and the navigator were killed.

 

 

                              OPERATIONAL DEVELOPMENT

 

 

Fundamentals.

 

            The fundamentals are to:

. Reach the target,

. Destroy it,

. Return.

That involved:

. Attaining suitable range,

. Accurate bombing, and

. Surviving.

            Each of those factors was intermixed; each having a significant affect on the other.

 

            Target selection was made by higher authority and was sent to us as an Operation Order.  One hoped that they had fully considered the two most important factors:

. where maximum disruption could be achieved.

. accessability.

 

Perceived Threat.

 

            Although diplomacy restricted public acknowledgment, the threats we trained for were :

. Hostile action from the very unstable and increasingly belligerent Communist influenced and armed Indonesia under Soekarno;

. Major Communist insurgencies through Cambodia, Laos, Vietnam, and Thailand; and

. A Communist advance possibly through Eastern Indonesia, Dutch New Guinea or Papua New Guinea.

 

 

            The Indonesian Air Force was quite formidable.    They had:

.  some 60 or more Beagle (2 engine Jet Bombers similar to the Canberra),

.  a small number of Bears (4 engine massive turbo prop bomber/reconnaissance aircraft)

.  a great number of Mig 15/17 fighters (roughly equivalent to our Sabres),

.  at least 2 squadrons of Mig21 (roughly equivalent to our Mirage when we finally got it operational), and

.   Numerous ground to air missiles.

 

            To fulfill our commitment to continental South East Asia, Australian forces (especially the AIF) assisted Malaysia in the Indonesian Confrontation in Northern Borneo.  Also, we built the large RAAF / Malaysian Air Force Base at Butterworth and stationed a Canberra and a Sabre (later Mirage) Squadron there.  Those actions contributed largely to the emerging nation, Malaysia.   However, the Malaysians reminded us at every turn that the base was theirs and that we were only there by invitation.

 

            By the time that Soekarno was toppled and the Indonesian real threat was diminished, the Vietnam War was underway and the role was even more complex.   Even though No 2 RAAF Squadron of Canberras was involved in the Vietnam war (the only war operations conducted by RAAF Canberras), the replacement programme for the type was well under way.

 

Operational Criteria.

 

            The Canberra was purchased as a strategic bomber which was a bit euphemistic.  In fact its role was more as a tactical bomber involved in a confined theatre of operations and the battlefield.  The thinking at that time was that a war would be of short duration and that there would be little use in trying to destroy the long term ability of an enemy to wage war.   Thus, large industrial complexes were not the priority but our concept of targets was stores complexes, transport facilities including rail, road and ship, and, possibly, direct battlefield strikes.   Small targets like road and rail bridges were predominate.   At the same time, high level was dictated to get suitable range and for survivability.

 

Woomera Attachment.

 

            We, the two crews went off to Woomera in August 1952 there to join a 9 Sqn RAF crew that had brought one of their aircraft out for the conduct of the test program.   The leader of the project was a British Army Major specializing in Anti Aircraft Artillery.  The objectives were to determine the capability of new radar prediction and aiming techniques against bomber evasive maneuvers.  The objective for the Air Forces was to develop evasive techniques and assess how much time was needed from the cessation of such maneuvers before bomb release.

 

            As a preliminary, we did some practice bombing and each crew’s accuracy was assessed.  That was later used to calculate the deterioration in results of the various maneuvers and the period of dedicated bomb run.   Both the Australian crews got their first experience of bomb delivery from the aircraft.  I think that all tests were carried out at 30,000 feet above which the anti aircraft artillery was considered to be ineffective.  It was all valuable learning but we came away more convinced that we should operate above 30,000 feet.

    

Early Bombing Efforts.

            The Canberra bomb bay was designed to accommodate 9 x 1,000 pound bombs hung on three triple carriers.   But, neither of our two original aircraft had the hardware to hang the bombs, nor the associated wiring, or the switches and indicator lights for the bombaimer in the nose .  But, as we formed No 2 Squadron in early 1954 (most of 1953 was taken up with test work and the Air Race), we had to get on with developing the aircrafts bombing role.   Consequently, the engineers adapted Lincoln equipment and fitted it.  The aircraft did a successful sortie with the standard 25 pound practice bombs at Evans Head bombing range.  Then, I was scheduled, with Jack Bell as navigator for a practice sortie.  We dropped the first bomb OK but on the second run, Jack or the range crew could not see any bomb strike.  We flew out to sea and checked all lights and switches.  Finally, we concluded a failure of the add hock system and that the remaining seven bombs were still in the bomb bay.   We returned to Amberley, parked the aircraft in the bomb safe area with the bomb doors closed and instructed the armourers that there were seven bombs still in the bay.   Somehow, there was a breakdown in communications as we heard nothing from the armourers.   As it was long after stand down, we went home.

 

            Next morning, a Saturday and a stand down day, the morning paper brought a rude shock.  “BROADWATER BOMBED” screamed the headlines!   Broadwater is a village on the river about 8 kilometers from the Evans Head range.  Late the afternoon before, a number of practice bombs had straddled the substantial river that runs through the town.  I went out to the base as fast as I could and things were really hotting up.  Correctly, the authorities were treating the incident very seriously.  It was apparent that Command would like to have me executed forthwith.   We were also very concerned to find out what had happened.

 

            When the Lincoln switching etc had been put into the Canberra it was not really suitable for the aircraft.  In the Lincoln, the bombaimer was seated in a spacious position with a clear view and comfortable access to all the associated controls.  In the Canberra, the Navigator has to leave his normal station and come forward to lie in the nose in a very uncomfortable position to peer through the bomb sight.  The switching had been installed on the side of the aircraft nose and was difficult for the bombaimer to see or operate.  What is more, there was a JETTISON switch in an even more difficult position.  When Jack was wriggling about in the nose to get a suitable position over the bomb sight for the second run, some part of his body must have knocked the Jettison switch ON.   The safety circuitry prevented the bombs from releasing until the bomb doors opened.  Consequently, as I finished the turn on for the second run, I opened the bomb doors and the remaining bombs sequentially released some 8 - 10 miles from the target.

 

            As it was a serious incident, a Court of Inquiry was convened firstly to find out what happened but more importantly to lay the blame on - guess who?  First, they could not understand the distance from the target and why would we open bomb doors so far away.  We explained that our first result had not been brilliant therefore we decided to extend the run just to get everything a bit more stable.   Also there was a very strong wind and our ground speed was very high meaning that the run was only about a minute in time.

 

            I certainly was not praised in the Court’s findings but it was probably better than I had feared as I was ready to resign.  The main result from the Court was that the ad hoc system was not used again and urgent action was taken to get the proper bomb beam and circuitry - action that should have been taken long before.

 

Survivability.

 

            At first we did not worry about survivability.  At that time, the Canberra operated so high and so fast that enemy fighters were not a real threat.   RAAF Operational Command, to which all operational elements belonged, scheduled frequent Air Defence Exercises (ADEX) in the Sydney area.  We operated normally except that our only “bombing” was with a camera to record our likely achievements.   But, Vampires which were the primary RAAF fighter, could not make the altitude and thus, they got no training.   Consequently, we were restricted to, I think, a maximum altitude of 35,000 feet and Mach .72.  But the Vampires could not hack that either.  I remember a Vampire pilot combat report that went something like this:

Radar directed me to a good position to turn into a curve of pursuit, from which I estimated to roll out at about 750 yards and close for the kill.  But at full power, I had a negative close rate, and broke off the engagement at 1,000 yards.

Subsequently, we were further restricted so that the defence elements could get some useful practice.

 

            At that time, there were no effective ground to air missiles.   Our Woomera trials showed that we had little to fear from Anti Aircraft Artillery while we maintained high altitude and speed.   Thus, in the early period, survivability from enemy defences was not a problem.   But that was to change rapidly with the emergence of the second generation jet fighters such as the Mig 15 and 17, the F86 Sabre, and eventually the Mig 21, the Mirage, and the American F100 series.   Indonesia was being supplied with sophisticated Air Force aircraft by the Russians.

 

Range.

 

            The Canberra was not fitted for air refueling.   Despite many approaches for the necessary equipment, the government would not countenance air to air refueling mainly because of the expense of airborne tankers.   With no outside help, we could only attain the maximum range at high altitude.  We developed a method of cruise climb as the most effective.   At a calculated height dependent on aircraft weight and ambient temperature, we would terminate the initial climb (in the mid 30,000 feet range) and set the most efficient engine power (about 7,500 RPM) and the most efficient Mach No ( I think .74) and let the aircraft ascend slowly as the weight diminished.   Nowadays, long range airlines do a version of that which they call step climb as they are prevented from our more effective method by Air Traffic Control considerations.  (In our time there was no one else up there).

 

            Later, when survivability became of considerable concern, we had to compromise all that, but more on that later.

 

Bombing.

 

            We only had a small force and were confined to HE (iron) bombs - we hungered for tactical nuclear bombs but that was dream time stuff.    For many of our targets, ships, bridges, railway lines etc., using conventional high explosive iron bombs (1,000 lbs HE), extreme accuracy was necessary.   But that was the problem.   Nowadays, guided bombs provide that but for us that was also dream time. With both survivability and range dictating high level, we set about perfecting our high level bombing skills.   That did not develop well. 

 

            For training we used the 25 lb practice bombs which, on impact would emit a burst of smoke to enable plotting.   We also had a small allocation of 1,000 HE to get used to the real thing ( probably bombs that were getting close to their use by date).   Our major bombing range was at Evans Head, in northern NSW, but it was only cleared for 25 lb bombs.   When we dropped 1,000 HE, we used either the offshore range just north of Townsville or a range near Darwin.

 

            With bomb release from 40,000 feet, the forward travel of the bomb would be 5 or more nautical miles (7 or so kilometers).  We had one of the best high level bombsights in the world, but the slightest discrepancy at release could mean a large impact error.   A bomb run required extraordinary coordination and skill from both the pilot and the bombaimer.   The bombaimer lay in the nose and used the bombsight to direct the pilot by voice commands to correctly align the aircraft until release.   Because of the speed and tactical considerations, it all had to be done in minimum time.   It was an incredible team effort.  The art was for the bombaimer to anticipate the corrections necessary and to convey them to the pilot by voice so that he would action the correct movement of the aircraft.  What is more, the aircraft had to be flown absolutely accurately - that is no slip, skid, or sloppy movement.

 

            At Evans Head, our results were very inconsistent and, on occasion, the error was quite large.  But at Townsville range dropping 1,000 lb HE, a good crew could be quite accurate.   As well as different bomb types, the other variable was different conditions at the two locations.  Over Evans Head, the windspeed at altitude was as high as 140 knots due to a jet stream that flowed during a large period of the year.  At Townsville, there was no jet stream and winds were quite moderate.

 

            My conclusion is simple.  The bombsight could predict the correct release point for the environment that it was in but it could not predict the variations during the bombs’s fall.   If the bombs inertia could maintain the release trajectory, then the impact point would be accurate.  However, the violent wind shear tended to overcome the inertia resulting in error.  The extent of the error would depend on the wind shear, and the inertia of the bomb.  The inertia would be less for the 25 pounder and thus its errors greater.   Such a conclusion is supported by the excellent results we attained using the radar bombing trainer that we finally got at Amberley.

 

            However, we were encouraged by the presumptions that:

. We would be operating in the tropics where jet stream conditions were less likely; and

. We would be using more stable 1,000 HE.

 

            Therefore, we concentrated on honing our high altitude bombing skills.

 

            Against that though was the factor of visibility.   As we had no radar, we were dependent on visual bombing and we were unlikely to get clear skies over the targets for much of the time.     

 

Night Bombing.

 

            We were capable of bombing at night in a lit up area or bright moonlight.  But otherwise, identification of the target was a problem.

 

            It appears that the RAAF had a stack of 4 ½ inch reconnaissance flares left over from WW2.  Operational Command issued a directive that we were to develop a technique for high level night bombing using those flares.   I got the job in about mid 1961.

            The 4 ½ inch reconnaissance flare was a long tube (4 ½ inch diameter and over one meter long), the forward part containing the incandescent substance, the other end containing a parachute.   When the flare was dropped, the parachute deployed slowing the descent and after a predetermined time the incandescent substance was ignited.  The flare would then drift down very slowly (due to the convection generated by the burning flare operating on the parachute) for about 4 minutes before burning out after which the remnants dropped quite rapidly.   Because of the fall out, the flares could only be dropped on a vast range - for us the range offshore from Townsville.

 

            I flew the first test.  We carried 8 flares and had decided that a stick of 4 would be appropriate.   The aim was, using a mixed load, to see if there would be sufficient illumination after dropping the stick of flares to then identify the target and then carry on with a bombing run.   That is, drop the flares, identify the target, bomb it.   No way!  From high level, bomb release and thus the start of the bomb run was a long way from the target and the flares would not illuminate that distance.   We did two runs dropping a stick of flares each time with negative results.

 

            Next test was for two aircraft both carrying flares.  We set up a racetrack.   The first aircraft dropped a string of 4 flares where navigation estimated the target to be.  The second aircraft came along two minutes later to see if a bomb run was possible.  Very difficult as the crew had to look through the flares.   Just to be sure, using the racetrack, we each carried out two dropping runs and two attempted bombing runs.  Still not satisfactory.

 

            Next test was again using two aircraft using a similar racetrack system but the second aircraft was 10,000 feet lower - that is under the flares.   It was very marginally successful and very dicey as the flares had different descent rates thus assuming a very ragged line and they did not always burn for the stipulated time and were prone to plummet.   However, the danger could be reduced by the bombing aircraft turning away immediately after bomb release which was still a long way from the target.   On this sortie, there was further developments which I will describe later.

 

            My conclusion was that it was not a reasonably effective method.   The problems were:

. From high level, one had to be able to identify the target at a long distance to then conduct a bombing run with release far from the target.

. The flares themselves destroyed the crew’s night vision.

. Plus all the other problems with high level bombing.

 

            I went on later to do some individual tests dropping the flares at 10,000 feet and doing almost a wing over to come back under at low level and drop a flare at low level right on the target for it to be used as a target marker.  A following bomber force could then bomb the target indicator.   That looked like a reasonable solution if we had target markers but we did not and it did not look like they would spend the money for that ordinance.   The RAF were using such a system and there seemed to be no reason to reinvent the wheel.  And there was still the problem of the considerable time in which the attack was highlighted and our completely defenceless aircraft were exposed to attack from the quite sophisticated fighters being supplied by the Russians to our potential enemies.

 

            On the second two aircraft sortie, the bomb doors on no 2 aircraft did not fully close after the final flare drop.   The crew tried to hand pump them closed to no avail.   I had already landed back at Amberley and was taxiing in when the tower informed me of the problem with no 2 and informed that the pilot would like me to come to the tower so that we could discuss the problem and plan further action    I did so with great haste.

 

            The pilot was Flt Lt Tom Thorpe, a very skilled operator.  After discussion we determined that there was damage to the bomb door hydraulic system, and on a flypast of the tower we were able to get a powerful spotlight on the belly of the aircraft.   There was a distinct hydraulic oil spill coming from the back of the bomb doors.   Unfortunately, the bomb doors cannot be isolated from the system and all hydraulic pressure would therefore be lost through that damaged system.   Therefore, the wheels would not extend or the flaps function necessitating a wheels up landing at a higher approach speed due to being flappless.

 

            A major danger was the aircraft catching fire on landing.  We anticipated that the cabin door would not be openable with the aircraft on its belly, and even if it could be opened, escape through there would be tricky especially if the aircraft rolled on to its starboard wing.   Tom did a slow run over the airfield jettisoning the navigators’ hatch (about 40 explosive bolts).  Then he did a copy book wheels up landing on the strip where all the emergency equipment was strategically positioned.   The crew had shut down everything on touch down - engines, fuel cocks and pumps, and all electricals to minimise fire risk.  However, when the aircraft was about half way through its landing slide, flames started to erupt from just aft of the partly open bomb doors.   Hydraulic fluid had pooled in the compartment there and was now burning.   My heart nearly dropped out of my body.   As the aircraft slid to a stop, both crew rapidly exited from the top hatch and the fire personnel quickly extinguished the fire.

 

            In all there was little damage.  The bomb doors were wrecked and there was repairable skin damage to the underside skin of the aircraft.   The cause was quite simple.  The parachute on the rear flare operated as, or before, the flare was released thus dragging the flare into collision with the rear bomb bay bulkhead shattering the rear bomb bay actuating jack.   As the bomb doors were considered vital hydraulics, the sub system could not be isolated.   Thus all hydraulic fluid was lost including the emergency hand pump reserve and all hydraulic services became inoperative.

 

            In the Officers Mess, members had learned of the emergency in progress and had kept the bar open.  A few drinks went well that night.

 

 

HI - LOW - HI.

 

            As time went by, our high level security diminished.   Indonesia got Mig 15's, then 17's, and eventually 21's which could all outperform us no end.  Also, missiles were coming into the picture.   We had no attack warning devices or any counter measures.  And we were not really satisfied that cloud cover and haze would allow us to see the target and bomb it accurately from high level on sufficient occasions as to make us an effective force.  So, we had to develop a compromise alternative which was HI - LOW - HI:

. high level transit outside enemy radar range,

. slow descent keeping below the radar sight line,

. low level approach to and attack of the target,

. low level immediate exit, then

. high level return.

Sure, range was lessened but it was the price we had to pay for a better chance of reaching the target and this technique optimized the time spent at economical high level.

 

            There were very few mobile early warning and control radars, thus the norm was for radars at fixed sites.   We knew the precise location of all the Indonesian radars.  Also we knew the type of radars installed and their performance.   With the addition of contour data, we could draw up a map of radar coverage and, more importantly, non coverage for all of their radars.   We could design a descent profile starting about 250 nautical miles from the station and slowly descending to be at low level about 80 nautical miles out and then do a low level dash to the target.   Luckily, we found that the most economical descent profile was at high speed which was probably safer in case we had been detected and it certainly reduced the crew’s twitter factor.

 

            So we set about training, concentrating on low level navigation and bombing.

 

Low Level Navigation.

 

            At low level, the Canberra was rough and the aircraft bounced and shuddered in even slight turbulence due to the low aspect ratio and rigid wing.   In the tropics, turbulence could be extreme during the day.    The later models with the “wet wing” were better as the weight in the wing damped out some of the reactions but, even then it was like riding an unsprung vehicle at 80 k down a rough dirt road.   All that led to fears of fatigue especially in the massive fuselage yolk to which the wings were attached.   Therefore, performance restrictions to 350 knots maximum and 3 ½ G were imposed.   Also, the Air Force decreed a minimum of 250 feet for low level training.  In a real shooting conflict we would go as fast and low as we could, but in training, we observed the limitations as a basis and aimed for excellence under those circumstances.

 

            Although the low level run to the target was not very long, we had to be very precise.  There was no future in having to search for the target because we were off course.  In the Canberra, the pilot hand flew the aircraft, did the map reading, fuel planning, and fuel log.   The navigator was very busy with the air and ground plot, the courses to steer and time based calculations.  At low level, everything was speeded up and a lot of fast calculation was necessary as we frequently had to deviate from the predicted course to go around a hill or take advantage of topographical concealment.  We pilots got quite adept at compensating for deviations by keeping a mental plot of the course alteration and time and thus reversing it as soon as possible.

 

            The first essential was flight planning.  We pored over maps to find significant features.  We may then alter our planned track to ensure that we could identify them.  We then marked our intended tracks on aeronautical series maps and cut them into strip maps always orientated to aircraft heading.  Then, we needed a vision of what those significant points would look like as we approached.  For geographical features, we got any contour maps available and tried to draw up a sketch of what it would look like as we approached.  For buildings, we would try to make a sketch referencing similar buildings or photographs.   Then we would mark the time elapsed on the strip map and attach the sketch.   All that had to be juggled on the pilot’s lap while he flew the aircraft and ensured no contact with anything rigid - there was definitely no future in that.

 

            We always tried to establish an Initial Point (IP) some short distance from the target.  The aim was to do any major corrections there so as to ensure a simple final run to the target. 

 

            Low level escape from the target was not really a navigational problem as all we had to aim for was getting near enough to base to use the navigational aids available.  The main aim was to “get the hell out of Dodge”.  First thing was that the enemy fighters knew that we were there as we had left a significant calling card.   They would most likely search for us along the shortest route home.  Thus it was best to build in a significant deviation before turning for home and subsequently climbing back to altitude.

 

            We trained very hard and I think that we were probably the best in the world at low level navigation.  Both pilot and navigator were working like one armed paper hangers and were completely rung out at the end of the mission.  But it was a hell of a lot of fun!

 

Low Level Bombing.

 

            Low level was pilot release from about 200 feet and at 350 knots.  We all became quite accurate at it.  But there was the massive problem of preventing the bombs exploding right under the aircraft; safety height was deemed to be 3,000 feet above the exploding bomb.  The first defence was to tail fuse the bombs with a 10 second delay so that the aircraft would be well gone.  But owing to the speed and low angle trajectory of the released bombs, they were likely to skip back under the aircraft and 10 seconds later - kabung!   Also, delay fuses had a failure rate.

 

            Therefore, the only practical uses of low level release was against shipping or a building which would prevent skipping and also assist penetration for armour piercing bombs, tail delay fused.  For those attacks, we continued practicing low level pilot release.

 

Toss Bombing.

 

            Another method of bomb release from low level was toss bombing.   The aircraft would approach the target at low level and high speed.  At a predetermined point, the pilot would initiate a high G pull up and release the bomb at a predetermined angle (about 60 degrees nose up).  The bomb would then continue to climb before arcing over into a very steep trajectory to the target??   In the meantime, the pilot would perform a wing over into a very steep descent to low level and escape.

 

            That technique was primarily designed for tactical nuclear weapons where accuracy was not as significant.   It overcame the problem of blast and radiation damage to the aircraft as it rapidly escaped.   At Woomera, RAAF crews developed the technique, I think for the RAF which did have tactical nuclear weapons.   My good friend David Glenn was on that project.  The RAF Vulcan nuclear bombing force subsequently used that technique.

 

            The Americans used toss bombing to some effect with iron bombs from their advanced attack aircraft using target acquisition radar and a computer controlled bombing manoeuver.  For us, without the sophisticated gear, it was not a goer because of lack of accuracy.

 

Bombing From 3,000 Feet.

 

            The only practical solution was for bomb release at 3,000 feet above ground level.  That is, we would approach the target at low level and pop up to 3,000 feet approximately 1 minute before bomb release.   But our bombsight was for high level and would not work at 3,000 feet.  So we had to improvise.   Linked to the Green Satin doppler navigation aid, we could use the bombsight for direction.  But it could not compute release point.   Thus, we would preset an angle on the sight head calculated for release speed and height above ground.  At calculated time after initial point, we would pop up to release height opening bomb doors on the way.  Then, the aircraft had to be stabilized at release speed and exact height (using target forecast barometric pressure) while doing directional corrections as demanded by the bombaimer.  Because of the fixed angle, the aircraft had to be perfectly level and stable at release point.

 

            Strangely enough, accuracy was quite reasonable, but the work load was terrific.  There was some range error, but that could be offset by dropping a close spaced stick of bombs.

 

Finger Four.

 

            Even with the Hi - Low - Hi profile, there was still danger that we could be detected and intercepted.  As stated before, the Canberra had no intercept warning or any type of defences.  Also, because of the eggshell canopy and the pilot being offset to the port side, rearward visibility was poor especially on the rear starboard quarter.   Thus, we experimented with flying a very loose left hand finger four to maximize combined look out.  It worked OK in that aircraft were far enough apart for each to do his own terrain clearance while still conducting adequate look out.  If fighters were detected, the only defence was to try and out turn them and disappear.  Was a slim chance which was better than do nothing.

 

            Then came the tricky bit - the bomb run.   Making the initial point spot on was even more important.  At pull up point, formation was abandoned and each aircraft initiated its own bomb run and turned on to the target.   Theoretically, there would be adequate spacing as the aircraft crossed over but that depended on the lead not having to do anything but a slight turn for final run in.   In any case we did a lot of looking - just another almost impossible extra.  Actually, the aircraft should not be in great danger of collision until after bomb release and then the pilot had more time for evasion.

 

            We did a number of these exercises using Evans Head bombing range.  Results were quite good.  But, we knew the Evans Head area so very well that it was relatively easy to make the initial point spot on which assisted a copy book approach.   In unfamiliar enemy territory; who knows??

 

            Weapons Research Establishment had been working on a low and medium level bombsight for some time, but it must have been in the too hard category, as it was always being put off.  I do not know if it ever eventuated but I doubt it as the RAF Vulcan force were still using a bodged up system for low level bomb aiming right up to the Falklands war.

 

 

Deployments and ADEXs.

 

            We were continually being tested and given opportunities to develop our skills through exercises laid on by Operational Command.   Regular ones were with representative targets in the Sydney area (camera assessment of the bombing run) which also gave training to the radars and fighter aircraft and even the SAMS at Williamtown.  Others were deployments at very short notice for selected operational segments (bomber squadrons, fighter squadrons, radars and radar operators etc) to Darwin there to carry out concentrated simulated operational sorties.  Darwin was a prepared operational base with limited pre stocked support, an air defence radar, and a live bombing and air to ground firing range.   The movement phase usually simulated a rapid response to an exercise designated threat with a time frame of commencing operations within two days of first alert.  All our aircraft transited fully armed ready for a rapid turn around.  Each of our aircraft carried 6 x 1,000 HE.   Of course, it involved the transport squadrons to shift our ground staff and sufficient spares etc to sustain operations for one month after which in real circumstances, the supply chain was expected to be operating.  Such deployments usually lasted for a couple of weeks of intense activity.

 

                                                                        FINISH UP

 

            I left the program at the end of 1962 to go to United States to fly B66 aircraft as an Exchange Officer.  At that time our systems were considered experimental mainly conducted by No 6 Squadron which I commanded and I do not know whether they were ever accepted as operational procedures.

By the time of the commitment of a RAAF Squadron of Canberras to the Vietnam war, the aircraft had long since become obsolescent and its replacement had already been ordered.  Also, in Vietnam the role was completely different, and the techniques that we developed were not appropriate.  But the aircraft and crews acquitted themselves excellently in the assigned role. 

 

            I regretted that I did not get the opportunity to do a tour on Canberras in Vietnam.  By the time that they were committed, I had almost completed a tour at the RAAF Base at Vung Tau, Vietnam, after which I was assigned as a planner and I did not fly for the RAAF again before mandatory retirement at age 50 years.

 

            When I read of the massive ordinance that modern aircraft can deliver with pin point accuracy, I get real jealous.  The electronic aids that they have are absolutely mind boggling.  We had no auto pilot, no navigation systems, no terrain following system, no radar, no defences, no warning devices, and not even an appropriate bombsight.   We, the pilot and navigator / bombaimer had to cover all of that and it was not easy.  But we loved it!   And I am still satisfied with what we accomplished developing systems that would have been effective if needed. 

 

            Remember that Indonesia initiated “Konfrontasi” in the early 1960 ‘s and Commonwealth Forces (including Australians) were involved in skirmishes around the borders of Malaysian Borneo and Indonesia.  Those actions continued until Soekarno was toppled in very late 1965.   I think that Indonesia had a healthy regard for our capabilities, probably far greater than warranted, and that may have been sufficient deterrent to prevent escalation of the conflict.