AHC: Peerless Air Ministry

[dave_r_gilbert]

The Hurricane suffers from leading edge drag. It has rough, sagging, gapped and bumpy surfaces. The wings are way too thick at 19% thickness to chord ratio at the wing root (cf 13.5% for the Spitfire). Could something like the P-51 be built by Hawker domestically?

Spoiler: Big pics

There is scope for hawker to do better than OTL - but not with the P51.
Hawker had a history of incremental improvement.
The hurricane can be looked at as an updated Hawker Fury, changed from a biplane to monoplane, with a merlin engine.
Immediately after the Hurricane was in service Hawker began work on the Tornado and Typhoon.
Principle differences from the hurricane were duralumin rear fuselage, and either RR Vulture (Tornado) or Napier Sabre (Typhoon) engine.
They kept the same style of thick wings as the Hurricane, which weren't great.
After the Typhoon the next step was to the Tempest, which was originally known as the Typhoon II, i.e. an evolution rather than a revolution.
Principle differences from the Typhoon was thinner wings, and as well as the Sabre either RR Griffon or Bristol Centaurus.
After the Tempest was the (sea) Fury, which originated from a requirement for a light Tempest fighter.

Possible changes in a PAM world:
1) Tornado/Typhoon get the thin wing, rather than waiting for the Tempest.
Better data from the farnborough wind tunnels would do it. Ithink the data existed, but was misinterpreted before it got to Hawker?
2) Tornado gets the RR Griffon instead of the Vulture. The development of the griffon was stopped for a while, and effort concentrated on the Vulture instead.
I think, without that shift, the griffon is about in the right time frame for the Tornado prototype.
3) Typhoon (instead of/as well as) Sabre gets Bristol Hercules. Too early for the Centaurus I think.
In OTL the air ministry insisted on 3 different engine types in the prototypes for the Tempest - they could have done the same here.
4) Tornado/Typhoon gets a carrier version - Hawker had a history of carrier aircraft, notably the osprey, nimrod, and sea hurricane, and a future with the sea fury.

 

[sonofpegasus]

In the PAM, The Tornado has been built with the Monarch H24 and the thick wing of the OTL Typhoon. The big change is that the Tornado ITL is in series production in 1941 and will become OTL's Typhoon without all the delays caused by the Sabre. ITTL the Typhoon might well be a different beasty!

 

[foresterab]

The recent discussion on hurricane fighters raises a question re Canadian production. Canada produced over 1,400 hurricane fighters from 1940 on via Plans shared from England.

At the same time they were also trying to expand the British Commonwealth Air Training Plan and importing trainers from the USA.
What would be the impact if the hurricane production was shifted to trainers in use not just in Canada but also Australia, South Africa, India and the Uk especially for initial flight training. Many students did basic training at “home” and the went to Canada for advanced training prior to deployment.

 

[Errolwi]

The recent discussion on hurricane fighters raises a question re Canadian production. Canada produced over 1,400 hurricane fighters from 1940 on via Plans shared from England.

At the same time they were also trying to expand the British Commonwealth Air Training Plan and importing trainers from the USA.
What would be the impact if the hurricane production was shifted to trainers in use not just in Canada but also Australia, South Africa, India and the Uk especially for initial flight training. Many students did basic training at “home” and the went to Canada for advanced training prior to deployment.

Australia is building it's own Wirraway (rather than using its cousin the Harvard).
Wirraway Whizzes by by Errol Cavit, on Flickr

 

[sonofpegasus]

I am working on both Canadian and Australian aircraft production through 1941/2 . Some of what has already been written in earlier posts rather limits the choices.

 

[sonofpegasus]

12.06 Making Malta tougher

On November 28th 1940 a very important resupply convoy had docked in the Grand harbour of Malta, this convoy brought much needed supplies to the island for alongside the essential food and other consumables there were significant quantities of munitions and spares and fuel for the RAF squadrons on the island. One cargo ship was carrying heavy equipment for the army units defending Malta, the significance of these items would only become apparent to the RAF a little later. So far as the army was concerned the arrival of an additional troop of 40mm Bofors AA guns was always welcome. The unloading of four Matilda II tanks, a cruiser tank Mk I (A9), cruiser tank Mk II (A10) and two Vickers Mk VI light tanks was definitely seen as improving the islands defensive capability . Additionally there were four universal carriers and an assortment of Motor transport.

The arrival of this small but potent armoured unit did much to bolster the morale of the Maltese Garrison and civilian population. Once the Tanks had been serviced and checked after their voyage from the UK they were painted in the stone wall camouflage pattern that was unique to tanks and vehicles used on Malta.

After much discussion within the High Command and the Civilian Administration on the Island the decision was made that the tanks would be used to bolster the defence of the Islands airfields rather than try and cover any of the potential landing beaches for a seaborne invasion.

The available universal carriers were assigned the task of moving and supplying the mobile 40mm Bofors guns that were sited around the island.

Within a short time of the tanks arriving at the airfields they were being used to help the RAF ground crews to drag badly damaged bombers clear of the runways.

The three airfields currently operational all suffered from the same problem, Malta is a small island, land is at a premium and flat land especially so. Add to that the fact that the landscape is crisscrossed with stone walls dividing the small fields and the nature of the problem becomes apparent. Since the arrival of the first Hurricane fighters in the late spring of 1940 the creation of more and widely spaced protected dispersal pens had been high on the priority list for the RAF. To this end whenever possible whatever machinery, manpower and other resources could be begged borrowed or acquired from both the RN and the Military garrison was utilised to this end. Sometime in December 1940 a Royal Engineers officer had been overseeing work being carried out on clearing stone walls and building new blast proof pens around Luqa airstrip when he espied the sole A 10 cruiser tank towing a wrecked Wellington from the runway. An offhand remark by an RAF officer about how much easier it would be to remove the old stone walls and fill in ravines if they had a bulldozer, set the RE officer thinking. Apparently during the final days of the battle of France this French speaking officer had been attached to a French engineering unit where he had seen and photographed a conversion done by the French army of a Renault FT17 into an armoured bulldozer. Using the French conversion as guide this officer sketched up a scheme for fitting a dozer blade to the A10 cruiser tank. Unlike the French conversion the turret would be retained on the A10. The biggest problem would be sourcing a suitable set of hydraulic rams powerful enough for lifting the blade and installing the pump in the cramped engine space. Eventual despite ram sacking the dockyard and Naval Base no suitable hydraulic system could be found. Therefore a rather Heath Robinson solution was adopted. Taking inspiration from a military recovery vehicle, a gib and hoist would be added to the back of the turret and with the gun facing aft a winch on the gin would lift and lower the blade. If the tank was needed for battle then either the blade could be pinned in the up position or if time allowed the whole thing could be unbolted. With the considerable resources of the dockyard exploited to the full the Mark 1 Malta Bulldozer Tank was hard at work lengthening Luka airfields runway early in the new year. The Royal engineers officer was later to receive a Military OBE for this and his subsequent work with the 79th armoured Division.

The expansion of the airfields on Malta was becoming ever more pressing as the need for fighter defence and the desire for bombers and Maritime patrol aircraft became apparent.

The Airfield at Hal Far was the principal fighter station on the island and was only now being upgraded to all weather status. Whilst the Maritime Command head quarters was at the Kalafrana seaplane base where the Sunderland flying boats and other seaplanes were based the land planes of the Maritime Command were spread around the islands airfields whether they could be given a home.

Work had commenced on the construction of an airfield at Qrendi earlier in 1940 but work was proceeding slowly.

The Mk 1 MBT was instrumental in the expansion of the satellite strip at SafI and its numerous blast pens.

Ta Qali air field had been used as a fighter base since mid November 1940 and would need expansion if aircraft larger than fighters were to ever use it.

The start of operation Compass and the need to intercept and stop the flow of reinforcements and supplies from Italy to Italian North Africa in conjunction with other events was to raise the priority of the completion and expansion of all three airfields to the point where it became perhaps the overriding priority for the British Government at the time. As Operation Compass evolved from a raid to a major advance the possibilities regarding the use of Malta as an air base to interdict Italian convoys and support the advance through Cyrenaica became manifest but also as air bases further west became available the ability to fly fighter reinforcements into Malta from the east became both a reality and a necessity.

 

[diestormlie]

I love the improvisation and outright bodging that goes on in wartime. Thank you for producing such a fine example!

 

[foresterab]

Nice work with the dozer. Reminds me of the older model D8 caterpillar dozers with the big C frame the blade attached to and a winch assist.
Especially when root hoods were added to clear land post ww2.

 

[sonofpegasus]

The FT-17 bulldozer as used in France 1940. OTL.

 

[unknownchild]

4 years later in america

 

[Peg Leg Pom]

. An offhand remark by an RAF officer about how much easier it would be to remove the old stone walls and fill in ravines if they had a bulldozer, set the RE officer thinking. Apparently during the final days of the battle of France this French speaking officer had been attached to a French engineering unit where he had seen and photographed a conversion done by the French army of a Renault FT17 into an armoured bulldozer. Using the French conversion as guide this officer sketched up a scheme for fitting a dozer blade to the A10 cruiser tank. Unlike the French conversion the turret would be retained on the A10. The biggest problem would be sourcing a suitable set of hydraulic rams powerful enough for lifting the blade and installing the pump in the cramped engine space. Eventual despite ram sacking the dockyard and Naval Base no suitable hydraulic system could be found. Therefore a rather Heath Robinson solution was adopted. Taking inspiration from a military recovery vehicle, a gib and hoist would be added to the back of the turret and with the gun facing aft a winch on the gin would lift and lower the blade. If the tank was needed for battle then either the blade could be pinned in the up position or if time allowed the whole thing could be unbolted. With the considerable resources of the dockyard exploited to the full the Mark 1 Malta Bulldozer Tank was hard at work lengthening Luka airfields runway early in the new year. The Royal engineers officer was later to receive a Military OBE for this and his subsequent work with the 79th armoured Division.

And thus was born the Armoured Vehicle Royal Engineers.

 

[sonofpegasus]

I an using authors fiat here, there were RE officers attached to French units in 1939/40 and these FT-17 bulldozer tanks had been converted in 1935 and were used during the battle of France. hence I hope this actual has the scent of plausibility rather than the stench of ASB, This will have quite big butterfly's in a few months!! Including a spat between the RTC and the RE!!!

 

[Schlock]

The driver is they need bulldozers. They don't have any. They do have several 28 ton tracked vehicles. They also have engineers and a base workshop. OTL they did far more than just fit a dozer blade to tanks at base workshops in North Africa and necessity is the mother of invention.

It reads fine to me.

 

[steamboy]

Aye it reads well and makes sense! Tis missing a threadmark though.

 

[Errolwi]

I an using authors fiat here, there were RE officers attached to French units in 1939/40 and these FT-17 bulldozer tanks had been converted in 1935 and were used during the battle of France. hence I hope this actual has the scent of plausibility rather than the stench of ASB, This will have quite big butterfly's in a few months!! Including a spat between the RTC and the RE!!!

I'm just listening to this podcast on Dieppe. One of the lessons learned (you always learn lessons, even when your main objective is something entirely different) is that you really do need something like a AVRE...
Hmmm, where might an armored bulldozer located on an airfield be handy in a few months...

 

[sonofpegasus]

12. 07 Testing, Trials and Tribulations



Early December had not been kind to Westland's test pilots. For just as they got production standard engines from power jets tragedy had struck, in less than two weeks two Whirlwind jet fighters had crashed with one test pilot missing, believed dead and the other in hospital with serious injuries.

How had this happened? Vernon Brown’s team from Farnborough were dispatched down to Yeovil to investigate the aircraft losses and help Westland understand what had gone so wrong. So far the surviving pilot had been in a coma and unable to give any indication of what had happened.

The sequence of events was that, whilst carrying out a series of high speed runs to explore the handling characteristics of the fully loaded production type twin jet engine fighter the first aircraft being flown by company test pilot had simply vanished over the Bristol Channel, with no wreckage being found.

The test pilots last radio message was that he had completed the first of his test runs at the set speed (of four hundred miles per hour) and had experience some buffeting but would proceed with his next test run. No more was heard from the pilot and when the aircraft failed to return the alarm was raised.

After a week searching for the aircraft it was decided to resume testing and to replicate the flights that the test pilots had been doing. A prototype PR Reaper fitted with a film camera would act as a chase plane. Whilst the Reaper could reach the test speed in a shallow dive it could not sustain it in level flight, therefore the flight plan was for the Reaper to get ahead of the Whirlwind by making a shallow dive from above and then the jet would accelerate past in level flight for the film camera. Both the pilots had done several days of dummy runs using two reapers with each pilots adopting the role of test aircraft and camera ship in turn. After several familiarisation flights with a Whirlwind and the Reaper at lower speeds it was decided to go for a high speed run. High over Devon in the crisp winter air the Reaper, that day flown by the Chief Westland test Pilot Harold Penrose, had been dived to gain speed and the pilot, looking over his left shoulder, watched as the Whirlwind accelerated past him. As it flew past everything seemed normal but as it got to what the Penrose estimated was a half mile ahead there was a sudden flash from the starboard jet engine. The Whirlwind was observed to yaw hard right whilst the starboard wing dropped rapidly. Over the radio the chase plane pilot reported that he heard a broken transmission that sounded like ‘getting out now’ as the jet aircraft was hidden by an increasing stream of smoke. Nosing over to follow the now rapidly descending jet the chase pilot radioed Yeovil that he had seen the pilot leave the aircraft but no parachute was observed. Continuing his dive the Reaper pilot gave a running commentary on what he saw and the location in north Devon where he expected the jet to crash. Observing the impact high on Exmore near the north Devon coast the Reaper pilot then made a sweep to the west and south in the hope of seeing a parachute. Nothing was seen, it was not till some hours later that Westland’s at Yeovil were contacted by the RAF to confirm that a seriously injured pilot had been found near Bampton in north Devon and had been taken to hospital in Taunton.

Whilst the news that the pilot was a alive was a relief his injuries were reported as severe and his survival was uncertain. A team was dispatched to Exmoor to the site of the crash, where next morning they were joined by the team from the RAE. Meanwhile the chase plane pilot had been thoroughly debriefed and the film from the cameras mounted on the Reaper developed. Analysing the film frame by frame in conjunction with the chase pilots observations initially pointed to a catastrophic explosion within the starboard engine, resulting in the disintegration of the starboard engine nacelle, this caused the aircraft to slew and yaw to starboard resulting in total loss of control authority at which point the test pilot had radioed and abandoned the aircraft. The team at the crash site were carefully recovering as much of the aircraft as was possible and it would be taken back to Farnborough for examination. The initial finding from the crash site were indicative of the aircraft having broken up as it plummeted to earth. So far the main body of the fuselage and both engines had been located but the remains of the outer starboard wing and most of the tail had yet to be found.

All flying on the remaining Whirlwinds had been suspended and Power Jets were not only sending engineers to examine both engines from the wreck but were attempting to replicate the engine flight profile on the test stand with an engine from the same preproduction batch.

It would however be some weeks before there could be any firm conclusions from the investigation. Westland were seeking permission to continue flying the Whirlwind at lower speeds to try and build up experience and gather more data on the handling characteristics of the aircraft.

The AM were divided on whether such permission should be given and Sir Hugh Dowding pointed out that there was no shortage of pilots volunteering to fly the aircraft. So after much angst permission was granted for the test program to continue but under strict guidelines.

On a vey still day in late December over the Bristol Channel Arthur Penrose pushed the nose down of the Whirlwind jet below the horizon and dived the aircraft keeping the throttles at eighty percent power.

As the speed built up the controls got heavier and as the aircraft passed four hundred miles an hour the controls started to get unresponsive and as the speed rose further the aircraft started to buffet heavily, pulling back the stick and getting the aircraft nose to rise took all of Arthur Penrose’s strength. Breathing rather heavily from the effort Penrose settled the aircraft once more on level flight and wrote a few notes on the pad strapped to his right thigh. He knew there would be serious recrimination over his actions but he felt that it was his responsibility to try and find out what had killed and maimed his fellow test pilots.

Upon returning to terra firma Arthur Penrose phoned Farnborough and spoke to Vernon Brown, informing him of the results of his flight and his conclusion that the loss of the two Whirlwinds might be to unrelated. The first loss could well be due to the aircraft handling problems in a dive and the second one to a totally unrelated catastrophic failure of the starboard jet engine. Sir Vernon Brown had listened and then confirmed that all the evidence they had so far collect from the wrecked Whirlwind on Exmoor was drawing them to the same conclusion regarding the catastrophic failure and resulting disintegration of the starboard jet effectively destroying the starboard engine and subsequently the aircraft. Vernon Brown added that he would send a recommendation that the high speed handling of the Whirlwind should be scrutinised as a possible cause of the loss of the other aircraft.

Having carefully briefed Petter as the head of the design team as to what had happened during his unauthorised test Arthur Penrose was relieved when Petter agreed that a systematic investigation of the high speed handling of the Whirlwind would start. For his part Arthur Penrose said he would canvass all the other test pilots then working on fighters to see if they had encountered similar problems with other aircraft.

Fortunately the high speed wind tunnel at Farnborough run by the Aerodynamics Department, the construction of which had commenced in1938 was just now being commissioned. Capable of simulating flight conditions at four atmospheres at six hundred miles an hour utilising models with a wingspan of up to six feet, it had been hastily decided that the first project would be an investigation of the high speed airflow characteristics of the jet Whirlwind. Comparison of the full scale aircraft test flights and the data from the wind tunnel would help validate the results from the new facility.

 

[Thoresby]

The problem with pioneering jets is the inevitable casualties as planes outstrip understanding of aerodynamics with fatal consequences.

 

[edqu]

Jesus these pilots are brave. I kind of assumed there wouldn’t be people like Penrose chomping at the bit to risk their lives.

edit: also there’s no threadmark

 

[steamboy]

Excellent update, it could be the fans breaking or compression issues or both (the 2nd one sounds like compression issues) but the chaps doing those test flights must have had the biggest brass balls, especially in the early jets.

 

[sonofpegasus]

Yes . I would call the period up to about 1950 as the 'heroic' age of test flying. At this time test pilots really did put their life on the line to push the flight envelope. All to often like Geoffry DeHaviland they ended up as lessons in 'Crash Investigation'.
In his book 'Wings on my sleeve' Eric 'Winkle' Browns describes vividly the cold blooded self believe and courage required to get into an aircraft (in this case the second DeHaviland Swift prototype) knowing that one of the worlds best test pilots and been killed flying one and the replicating that pilots last flight in an attempt to discover what went wrong. Happily in this case 'Winkle' did not only survive but also uncovered the probable root cause of the loss of the other prototype. However 'Winkle' Brown was not unique, at this time in aviation history test pilots all over the world were chancing their lives in pursuit of Knowledge, performance and the unknown.