An Allison V-1710 with a two-speed supercharger in 1942 (3 Viewers)

[PAT303]

Er, it was in 1941 that my home city received its worst bombing raids. Even when Germany was daft enough to attack the Soviet Union there was a very real perception that, at best, an invasion of Britain was merely delayed. Whilst the Barbarossa assault continued forward and reached the gates of Leningrad and Moscow that perception was still current. It was only in 1942 that the halt of the Germans and some reverses for them changed the perception. Until then the home islands were, not unreasonably in the light of the time, under a genuine threat. The priority pure interceptor rôle was thus current until well into 1942. The last raid on my home city was in May 1944. The last cruise missile raid on London was on the 29th of March 1945. Dealing with V1 raids was very much an interceptor rôle, within a whole defence system.

We saw this again in the 1950s and 1960s when the emphasis of British fighters was to get fighters up and away to meet Soviet bombers as fast as possible in all weathers. Hence the English Electric Lightning with the climb rate of an angel leaving work on a Friday and the fuel storage of a human bladder with prostate difficulties.

Again you should actually read what I wrote, from 1941 the RAF switched from the BoB defensive doctrine to aggressive cross channel operations such as the leaning on France fighter sweeps, yes there was a need for defensive fighters and yes Britain as bombed after 1940 but the shift was to go on the offesive, to do that you needed fuel.

 

[PAT303]

Escort to the Ruhr wasn't a factor. The RAF neither cared about, nor was equipped, for daylight strikes to the Ruhr. Escort at night was off the table.

Because they had fighters with only 85G of fuel, it's a bit hard to do anything when you can't fly out of sight of home.

 

[drgondog]

Don't people read????, I clearly stated that having extra fuel allows for a whole range of different missions that historically the Spitfire didn't fly because it didn't have the range, if range wasn't important why did every fighter once suitable engines were available have aux tanks drop tanks or both fitted?.

Conversely, I have tried to point out that IT WASN'T IMORTANT ENOUGH TO EITHER THE RAF or Ministry of Production to implement major changes to increase range.

 

[yulzari]

Again you should actually read what I wrote, from 1941 the RAF switched from the BoB defensive doctrine to aggressive cross channel operations such as the leaning on France fighter sweeps, yes there was a need for defensive fighters and yes Britain as bombed after 1940 but the shift was to go on the offensive, to do that you needed fuel.

Those offensive sweeps were to draw in the Luftwaffe and keep them from moving to Russia. In support of the Soviet Union and as a demonstration of offensive action to assist the alliance with the Soviet Union. Not to try extending offensive raids in themselves. The fighters principal rôle remained the air defence of Great Britain not escort bombers as far as possible. The operations were to be within the range of the existing interceptors.

Certainly later on they ranged further with weaker opposition but that was after the invasion and widespread bombing became seen as low risk. One should not restrict the real Battle of Britain to 1940. It continued, different forms, until the Luftwaffe went away to the east. The later 1941 cross Channel operations were a response to Barbarossa not to any offensive plans in themselves. When actual operational offensive actions began it was after the Germans were held and the Eastern front stablised. For a given degree of stability. That was when extending the home fighter's ranges began to override the interceptor rôle, with a delay to recognise the change and then design and build in the means to extend the ranges. Range needs had then become more important than base interceptor requirements.

I agree, with hindsight, that this step should have been made earlier and small improvements could have been done earlier without compromising the base rôle but we know when it was safe to do so. They did not and were understandably conservative. To them the prime rôle of their fighters was shooting down bombers over the UK and remained so until 1942.

 

[MikeMeech]

Spitfire IIA with 40 gal tank.
View attachment 879720
Tested at Boscombe Down in Sept 1941 (?) .
Some were flown by Sqadron Nos 66, 118, and 154.
I don't know if any squadron was fully equipped or not.
This was the 2nd attempt at fitting the wing tank. It had been tried on a MK I.
Somewhere there was a report on the MK I. The Report on the MK IIA gives speeds and climbs.
The MK IIB had metal alerions and handling was a marked improvement over the MK I and the plane was considered satisfactory as a fighter.
Granted this tank has a fair amount of drag and cost a bit over 20mph in speed. It also cost about 700fpm in climb under 20,000ft.
How much was drag and how much was weight can be argued. Fitting the fuel tanks inside would get rid of the drag (except for a few mph) but the weight is still a problem.
Engaging the enemy over the French/Belgian coast is problematic. Near the end of the misson/sweep (longer than a normal Spitfire) there isn't going be much difference.
At the start or entry into enemy airspace the planes carrying the extra fuel are going to have much degraded climb.
Early MK Vs (eight gun) show a bit better climb using standard 2850rpm and 9lbs climb compared to the MK IIs with Merlin XII engines. Above 20,000ft the MK Vs show more advantage.
MK Vs seem to show rather different performance from each other.
A MK Vb with standard tanks was within 15lbs of the MK IIA with the fuel tank. Extend range Vb might have had similar performance to a standard IIa? Or IIb? Is that good enough in late 1941?

Hi
Actually all rather earlier than Sept. 1941 with development starting before May 1940, see image below from Morgan and Shacklady:

Some other images from Green & Swanborough 'RAF Fighters part 3' page 16:

Actually used on Operation 'Sunrise' on 24 July 1941, from 'Fighter Command War Diaries Volume 2' by John Foreman:

I hope that is of interest.
Mike

 

[Steamed_Banana]

Let's keep in mind, they did eventually produce the Spitfire Mk VIII, it proved extremely useful in the 'outer Theaters', and it had a very good rate of climb.

 

[tomo pauk]

Conversely, I have tried to point out that IT WASN'T IMORTANT ENOUGH TO EITHER THE RAF or Ministry of Production to implement major changes to increase range.

Institutional inertia, shortsightedness and turf war were a thing. So were the wrong purchases and pet ponies (hence we have two - two - factories making the Bothas, and the turret fighter made in 1000+ copies, so was the biplane fighter made in many hundreds in the late 1930s). Nobody have had monopoly on these shortcoming, not the Japanese, not the British, not the Germans.

Spitfire needed minor changes to increase the range. What was not there was the doctrine to call for that.

Let's keep in mind, they did eventually produce the Spitfire Mk VIII, it proved extremely useful in the 'outer Theaters', and it had a very good rate of climb.

Stop noticing

 

[Geoffrey Sinclair]

The Spitfire design decision to delete wing fuel tanks in favour of heavier armament gave it one of the simplest fuel systems around, two tanks right beside the engine, it meant more changes than other types to draw fuel from wing or external tanks. It gave the mark I all the range it needed for the war it mostly fought, the enemy coming for it. The Spitfire still had range needed for the priority mission for 1941, defend Britain, even though the more powerful engines being fitted to the II and V were reducing range. Also by 1941 everyone wanted the Spitfire, in particular the latest versions, something that would continue until 1944. While 1941 would see the Spitfire struggle to keep up performance wise with the Bf109, being over taken by the Bf109F-4 and then most obviously by the Fw190A. It would take until mid 1942 to match the Fw190A, then came matching anticipated increases in Luftwaffe fighter performance in 1943. Extra range was down the list of priorities over better performance and more aircraft.

There is no doubt even providing enough extra fuel so Spitfires arrived at the French coast would have cut the loss rates, the overall situation, pilot training and Fighter Command tactics were the big contributors to losses. The Germans were not worried about France, the Spitfire would need to reach Germany before any strong reaction could be expected.

The mark III upped fuselage fuel from 85 to 99.5 gallons, of which around 5 gallons would be available for range under the RAF 15 minutes allowance rules.

The C wing had a different attachment to the fuselage compared with the A and B wing, whether that precluded A and B wing fuel tanks is unknown, mark Vc production began in October 1941 at Supermarine, April 1942 at Westland and August 1942 at Castle Bromwich (after 1 in June). Given the usage of ferry tanks the failure to provide around 50 gallon combat drop tanks to Spitfires in 1941/42 is an obvious error, the question being whether they could be designed and made in numbers at the time, who was asking for them and who was against the idea, 50 gallons plus tank would be around 400 pounds.

1942, same issues around Britain, with the prospect of a viable bomber force extra range was becoming more desirable but the 8th Air Force was not thinking in terms of fighter escorts for most raids. At Malta the enemy was coming for the defences. In the Western Desert how many allied day bomber missions were on targets beyond Spitfire range? The armies were mostly around the "front line", there were the well defended ports, the coast road and the enemy airfields, nothing else but to be in Bf109 range you had to be in Spitfire range.

1942, working off the mark III Supermarine did a comprehensive update of the airframe to create the mark VII (from September) and VIII (from November) matched to the Merlin 60 series, in the VIII case adding around 46% more fuel for no handling issues, the similar P-51 upgrade also added about 46% more fuel but had handling issues until about half the extra fuel was used, but of course the P-51 was carrying 80% more fuel. Even so it meant the VIII with 90 gallons external fuel had a theoretical combat radius of 300 miles using fast cruise.

Also in 1942 the Merlin Mustang became a reality, giving better performance coupled with much longer range, hundreds promised for the second half of 1943

1943 In Q1 the Tunisia fighter quality crisis, rushing Spitfire VIII and IX to counter the better performance of the Bf109G and Fw190A. Would there be another crisis when the inevitable Bf109 and Fw190 upgrades appeared? Again ranges to targets in Tunisia do not seem to have been a big issue given allied base locations. Sicily again had few targets and many of the airfields were Bf109 distance from Malta. Finally Italy, with many more targets, bridges, more roads, bigger and more complex rail system, factories and so on. By which stage the Spitfire VIII were flowing into theatre while the Luftwaffe was departing.

Also in 1943, providing a longer range Spitfire force in Britain is not going to do much to allied or axis casualties unless the 8th Air Force agrees to limit targets to those within escort range.

Early 1943 quality was the issue and only the Spitfire could provide it, the P-47 was arriving but it would be taking on fighters half its weight, could that work? Apart from operations out of Britain as the medium and light bomber forces grew, where was the big push for more Spitfire range, to the point of interrupting Castle Bromwich production? Lots of Hurricanes needed replacement in the fighter role and even a Spitfire V would be an improvement. In any case getting a Griffon Spitfire into production was a priority, the Luftwaffe was becoming overdue for a fighter performance upgrade. Mustangs could provide the range. Overlord was coming, expect the biggest air fights and probably losses of the war as the Luftwaffe throws everything into defeating the invasion, once again the enemy coming for the Spitfire. Even if range is an issue look at the Overlord phase lines, out of Normandy in under 3 weeks, plenty of room for airfields which removes the risk of good weather in France but bad in Britain giving the Luftwaffe a great opportunity.

Now what history knows, the Luftwaffe fighter performance held largely steady from early 1942 to the final quarter of 1944, upgrades were concentrated on heavier armament and protection, the P-47 proved itself in the second half of 1943, taking pressure off the Spitfire, the Mustang program suffered delays, the 8th Air Force changed tactics but not targets creating a world wide Mustang shortage that short term had to be fixed by RAF allocations, the Luftwaffe day fighter force suffered a major quality loss in the first 5 months of 1944 even though numbers held, while the Luftwaffe bomber force took large and irrecoverable losses bombing Britain in the first months of 1944, making the Overlord air war often one sided. The Overlord ground advances were much slower than planned for around the first 7 or so weeks then raced ahead.

Knowing that then the usefulness of changing Castle Bromwich to VIII in 1943 or just getting the late war 2x18 gallon wing tanks into the IX, along with the ability to carry 1,000 pounds of bombs etc. was clearly worth the loss of production. Looking forward it was another matter, there always seemed to be a big gap between demand and production, quality now and quality needed tomorrow. That leaves the use of drop tanks in 1941/42 with enough fuel to make France to overcome the fear of interception when carrying the tank, then bigger tanks as experience grew. Note the truly cheap "paper" external tanks came later.

 

[Steamed_Banana]

Some production numbers here (just googling, so correct me if I'm wrong)

British production:
Spitfire Mk II production: 920
Spitfire Mk V production: 6,479
Spitfire Mk IX production: 5,665
Spitfire Mk VIII production: 1,658

Hurricane Mk II production: 8,600 (451 Mk IIA, 2,948 Mk IIB, 4,711 Mk IIC, 296 Mk IID, 270 Mk IV)

Boulton Paul Defiant produced (through 1943 !!): 1,064
Hawker Henley: 202
Armstrong Witworth Whitley: 1,814
Avro Manchester: 209
Beaufighter Mk II: 448

US Production:
P-40F and L (total): 1,831
P-40 (Allison types) prior to 1944: 7,570
P-38 Lightning (1942-43): 3,212 (1019 in 1942, 2,193 in 1943)
P-47 Thunderbolt (1942-43): ~3,000 (includes 171 B and 602 C which I don't think were combat ready)
P-51A Mustang + A-36 (1942-43): 810 (500 A-36, 310 P-51A)
P-51B and C (I couldn't find the number for 1943, hopefully one of our P-51 experts here has it?)
F4U production in 1943: ~ 1,200 (not sure how many of these were really combat ready types)
F4F / FM1 Wildcat / Martlet production 1942-43: 3,138 (1,988 from Grumman, 1,150 from GM)
F6F Hellcat production 1943: 2,545 (I believe these were all F6F-3)
P-39 Airacobra production through 1943: ~8,000

Losses -
Luftwaffe losses in North Africa 1942-43: ~3,000 (600-700 aircraft in action or accidents, 2,400 counting aircraft left on airfields etc.)
Regia Aeronautica North Africa aircraft losses 1942-43: 400-500 aircraft + unknown (or i couldn't find data) for left behind / lost on the ground
Luftwaffe + Regia losses Sicily campaign 1943: 2,011 (320 (225 German and 95 Italian) in action or operational, 1,691 lost due to captured airfields etc.)

RAF / DAF losses North Africa 1,800-2,000 aircraft
USAAF losses North Africa ~1,800 aircraft
Combined Allied aircraft losses Sicily ~200-300 aircraft (including 140 US)
RAF aircraft losses Burma and India (through 1945): ~ 1,300 aircraft
US aircraft losses CBI (through 1945): ~600-700 aircraft

Google also claims that Regia Aeronautica lost 5,200 aircraft between June 1940 Sept 1943, and Luftwaffe 3,540 aircraft. Presumably most of these were lost on the ground / abandoned.

Comments:

• I could not find the total number of Luftwaffe losses in fighting over the channel in 1942-43, but I would bet you a beer it's less than what they lost in the MTO, mainly because of all the captured and abandoned aircraft lost as a result of the Allies taking ground. The ability to capture enemy controlled territory was a major advantage of the fighting in the MTO for the Allies.
• Just taking a wild guess here, but I would bet a beer that about 5,000 of those 8,000 Hurricane Mk II were 'extra', as were about 3,000 of the Spitfire Mk V. If we can assume that something better in terms of performance and range could have been possible in time to be fielded in 1942-43. If not I'd say swap Hurricane production for Spitfire as we already discussed.
• The reason being that both Hurricane and Spit V were extremely limited in both range and endurance. This was a big problem for both in North Africa, and in Burma and India, and for the Spit V in Australia. It basically prevented it's active use in the South Pacific Island campaigns which could have been a very helpful contribution. The Spit VIII, for all it's capabilities, did not have a huge combat advantage over the Ki-43 and other JAAF fighter aircraft, but it did have an advantage and more importantly allowed the British to bring the fight to the Japanese more than ever before in the campaign.
• I will also guess that 4,000 of the 8,000 Airacobras produced could have been skipped. The ones that were built should have been sent to the Soviets.
• Probably half of the P-40E, K, M and N could have been better replaced by F/L types. The F/L was viable in the MTO through early 1944 and would have been useful in the South Pacific and China / Burma / India through the end of the war.
• The CBI was a truly tertiary Theater of War for the British, their only real necessity there was to protect India which was in fact threatened for a minute at the end. The US had their own reasons but it was not as important as the PTO or Europe for them either. But MTO was not so trivial, Suez canal, Egypt, the supply route to India etc., and the middle eastern oil (both keeping it and denying it to the Axis) were all very important. It also served as a useful Theater for damaging the Axis armies, building up British and American land fighting capabilities, and knocking Italy out of the war which I think was a bigger deal than people usually acknowledge. El Alamein and Italy's collapse were both major losses to German prestige and morale.
• There was some degree (we can debate how much) of squandering of the Merlin XX engines
• There was a shortage of the best US and British fighter aircraft through the end of 1943 - especially the Spitfire Mk VIII, P-38, F4U, and P-40F/L. I was quite surprised by the large number of F6F produced (if that number is correct) but if it is correct, it seems like more of these could have been deployed by the USN sooner and given to the British sooner. The P-47 was arriving in some numbers though as we know it took a while to iron out some of the problems with the type. But you can see in the production numbers a hidden value of this aircraft. Quantity has a quality all it's own, up to a certain point. Definitely more useful than Hurricane IIs or P-39s.

 

[yulzari]

Reference the Defiant continuing in production into 1943. Whatever the debate about turret fighters there was a need for high speed target tugs. Boulton Paul had a factory making Defiants. The two came together to produce a very useful aeroplane for the high speed target tug rôle. Used to a limited extent by the USAAF too.

If they stopped making these where would they find high speed target tugs? The Hawker Henleys initially used had their factory go over to making Hurricanes in 1940 and the Henley, which was used for several years despite needing careful attention to overheating with large target tows requiring high revs at low speeds, was never about in enough numbers for the demand from the RAF, RN and Anti Aircraft Gun training. The last production Fairey Battles, whose production ended in August 1940 as target tugs, was simply too slow. The Defiant was ideal for the task and very necessary and it's continuing production from an existing factory with a well developed airframe was an exceedingly wise opportunity taken. As one can see, every alternative stopped being made before the autumn of 1940 when the official Battle of Britain was still very much in progress. I wouod argue that the Boulton Paul Defiant was responsible for bringing down at least as many enemy aeroplanes through its contribution as a high speed target tug as it did as a fighter. Probably more if you count the V1s brought down. Both through pilot aerial gunnery experience and through the whole of the Anti Aircraft Guns of the army and Royal Navy. Not only in the UK but overseas as well. Serving in Canada, Caribbean, Mediterranean, around Africa and India. Gave Sterling service meeting á very real need.

 

[Steamed_Banana]

I figure you ought to be able to use Hurricanes, god knows there were plenty of those. Especially the older types once the Hurri IIs were available. Same for the older mark Spitfires.

 

[Engineman]

Now what history knows, the Luftwaffe fighter performance held largely steady from early 1942 to the final quarter of 1944, upgrades were concentrated on heavier armament and protection, the P-47 proved itself in the second half of 1943, taking pressure off the Spitfire, the Mustang program suffered delays, the 8th Air Force changed tactics but not targets creating a world wide Mustang shortage that short term had to be fixed by RAF allocations, the Luftwaffe day fighter force suffered a major quality loss in the first 5 months of 1944 even though numbers held, while the Luftwaffe bomber force took large and irrecoverable losses bombing Britain in the first months of 1944, making the Overlord air war often one sided. The Overlord ground advances were much slower than planned for around the first 7 or so weeks then raced ahead.

Hi Geoffrey,

I do think that the Luftwaffe Fighter performance actually changed a lot from early 1942 to Q4/44. The effectiveness might be viewed differently from the technology, and the "performance against the allied air forces holding steady", could be read as a tremendous increase in performance, given the tremendous increase in the performance of the allied air forces!
Very broad-brush, the German fighters had many problems with engines in mid 1942. Most DB601/605/603 and BMW801 engines were de-rated due to fuel and metalurgical problems
until late 1943 when they regained full ratings. By early 1944, tactics and specialised Bomber attack fighter variants were well established. Furthermore, night fighter sub-types, with modified armament also saw step-changes in AI radar performance (generally out-paced though by Allied AI radar tech). Late Spring 1944 saw the introduction of the DB 605 AS high altitude engine into variations of the High Altitude Bf 109 and by June 1944, the general introduction of MW50 power boosting made big improvements of the low/middle power ratings of many German Aero-engines. September 1944 saw the introduction of the JUMO 213 powered Fw 190 D-9. Of course, I do think that the Luftwaffe fell below the abilities of the Allied air forces in about mid 1943, but they were certainly a resourceful enemy. Q4/44 onwards saw further technical developments by the Luftwaffe, such as the superior Me 262, but most of these late developments , although sometimes superior, were just bright sparks within a rapidly overwhelmed force.

Eng

 

[tomo pauk]

Reference the Defiant continuing in production into 1943. Whatever the debate about turret fighters there was a need for high speed target tugs. Boulton Paul had a factory making Defiants. The two came together to produce a very useful aeroplane for the high speed target tug rôle. Used to a limited extent by the USAAF too.

If they stopped making these where would they find high speed target tugs? The Hawker Henleys initially used had their factory go over to making Hurricanes in 1940 and the Henley, which was used for several years despite needing careful attention to overheating with large target tows requiring high revs at low speeds, was never about in enough numbers for the demand from the RAF, RN and Anti Aircraft Gun training. The last production Fairey Battles, whose production ended in August 1940 as target tugs, was simply too slow. The Defiant was ideal for the task and very necessary and it's continuing production from an existing factory with a well developed airframe was an exceedingly wise opportunity taken. As one can see, every alternative stopped being made before the autumn of 1940 when the official Battle of Britain was still very much in progress. I wouod argue that the Boulton Paul Defiant was responsible for bringing down at least as many enemy aeroplanes through its contribution as a high speed target tug as it did as a fighter. Probably more if you count the V1s brought down. Both through pilot aerial gunnery experience and through the whole of the Anti Aircraft Guns of the army and Royal Navy. Not only in the UK but overseas as well. Serving in Canada, Caribbean, Mediterranean, around Africa and India. Gave Sterling service meeting á very real need.

When a military aircraft, that is designed and made initially for combat purposes, is touted to be irreplaceable as a target tug, we know exactly how much it was a mistake that it ever saw the light of the day in the 1st place.

 

[MiTasol]

I figure you ought to be able to use Hurricanes, god knows there were plenty of those. Especially the older types once the Hurri IIs were available. Same for the older mark Spitfires.

Target tugs require a large winch fitted internally and there was not much room in the back of the Hurricane.

Target tugs require a winch operator carried internally who had clear visibility of the drogue and there was not much room in the back of the Hurricane

The winch and operator would both create a severe CoG problem.

 

[MiTasol]

When a military aircraft, that is designed and made initially for combat purposes, is touted to be irreplaceable as a target tug, we know exactly how much it was a mistake that it ever saw the light of the day in the 1st place.

I do not know about you but I can not name one country that designed aircraft specifically for the purpose of being a target tug.

Target tugs were absolutely necessary but, afaik, every tug started life as something else.

 

[yulzari]

I do not know about you but I can not name one country that designed aircraft specifically for the purpose of being a target tug.

Target tugs were absolutely necessary but, afaik, every tug started life as something else.

Miles Monitor

 

[Engineman]

When a military aircraft, that is designed and made initially for combat purposes, is touted to be irreplaceable as a target tug, we know exactly how much it was a mistake that it ever saw the light of the day in the 1st place.

There were the Tempest and Sea Fury Target tugs.

Eng

 

[tomo pauk]

There were the Tempest and Sea Fury Target tugs.

Eng

Very successful aircraft that found another role to do. Something that does not apply for Defiant.

 

[Shortround6]

Very successful aircraft that found another role to do. Something that does not apply for Defiant.

I defend the Battle, there is no defense for the Defiant.
The British had time to play with a few dozen Hawker turret Demon biplanes to figure out if it was actually going to work like they thought (put gun cameras in the turrets) like they thought before investing how many thousands (millions?) of pounds in the idea.

 

[Engineman]

The Defiant is somewhat maligned for not being a Spitfire. However, as a two-seat aircraft with a heavy power-operated turret, it performed well in its designed function.
Unfortunately, the whole concept of Turret armament continued to plague "bomber fighters", and particularly RAF Doctrine. It seems that the Official realisation of the vulnerability of the Defiant was not realised until the early stages of the BoB. By that time, the chances of BP changing their Defiant production to anything else in short order were non-existent. That said, Defiants did do some useful work in the learning days of British AI radar, and with specialised ECM, possibly quite efficiently, flying with just one early Merlin.
The real decisions about British Aircraft production lay with the Government Minister, the Ministry's and The Leaders of the RAF. A total attack on the production orders of the time would require an immense amount of work and would probably still not reveal all the details and subterfuge!

Eng