A Critical Analysis of the RAF Air Superiority Campaign in India, Burma and Malaya in 1941-45

[Schweik]

I think you are arguing for the sake of arguing, I suggest you read the links M Williams put up a page back, theirs evidence a plenty of Spitfires flying long range missions.

I did indeed read them. As I already pointed out, some of those links and the speculative article about turning a Spit into a LR fighter were already quite familiar to me before this thread even started. Seems to be difficult for some of you guys to grasp that other people look at that data and come to completely different conclusions.

Since you offered an assessment of my mentality in this discussion, I'll do the same - I think a couple of you are caught up in wish-fulfillment fantasy.

Of course if you somehow strap enough fuel on to a Spitfire it can fly as long (or almost as long) as any other plane. Depending on the version it has basically the same engine as the Mustang -with enough fuel flowing through it and enough oil lubricating it, it will keep chugging along for the same amount of time on either airframe. So if you connect it to a supertanker you can fly around the world... fly to the moon if there was atmosphere to fly through.

The Mustang has some advantages due to it's rather freakishly low drag and the push from the exhaust etc., but the main difference here is the very reason the Spitfire was so great - it's thin wings and small body. It was an agile dogfighter and an interceptor. This is why it has a great climb rate, turn rate, good combat speed and so on. But it doesn't have a lot of room for fuel in those wings (it barely had room for big guns). That is really the problem.

And you can try to wiggle out of it by strapping ugly 'slipper' tanks to the bottom and stuffing some bags full fuel in parts of the wings, overloading rear fuselage tanks and so on. But if you do too much of that you are losing the elegant interceptor and creating something more like an overloaded delivery truck. Or a Fairey Fulmar.

If you degrade the performance sufficiently and require pilots to fight with those external boxes on the bottom, you no longer have a fighter with an advantage over the enemy planes. Your escorts are also going to have to chug along at relatively low speed and altitude and be vulnerable to being bounced on the way to the target. It defeats the purpose. And it still didn't have the kind of range you really needed. THAT, and no other spurious reason, is why it wasn't done. If they could have done it they definitely would have.

No one fighter was good at everything. There is a bit of a paper / scissors / rock aspect to fighter design.

 

[RCAFson]

Just for reference, here's some extracts from the June 1944 Mustang III Pilot's Notes:

(iv) Aerobatics and spinning are permitted, except when
carrying wing bombs or tanks, or when carrying fuel in
auxiliary fuselage tank. See paras. 44, 46.
Rolls of any sort should only be practised above 10,000
feet.

(vi) When fuselage tank is filled, flying must be restricted
to straight and level and no manoeuvres other than very
gentle turns should be attempted until at least 40 Imp.
gallons (48 U.S. gallons) have been consumed.

42. General flying
(i) Stability.-Except when carrying full fuselage tank,
the aircraft is stable longitudinally, laterally, and direc-
tionally. When the fuselage tank is full, the aircraft is
longitudinally unstable in all conditions of flight, and
tends to tighten up in turns; until at least 40 Imp.
gallons (48 U.S. gallons) have been consumed from the
fuselage tank, no manoeuvres other than very gentle
turns should be attempted.

 

[Schweik]

I don't think that it's a surprise to anyone here that the fuselage tank being full made Mustangs unstable... ?

 

[RCAFson]

And you can try to wiggle out of it by strapping ugly 'slipper' tanks to the bottom and stuffing some bags full fuel in parts of the wings, overloading rear fuselage tanks and so on. But if you do too much of that you are losing the elegant interceptor and creating something more like an overloaded delivery truck. Or a Fairey Fulmar.

If you degrade the performance sufficiently and require pilots to fight with those external boxes on the bottom, you no longer have a fighter with an advantage over the enemy planes. Your escorts are also going to have to chug along at relatively low speed and altitude and be vulnerable to being bounced on the way to the target. It defeats the purpose. And it still didn't have the kind of range you really needed. THAT, and no other spurious reason, is why it wasn't done. If they could have done it they definitely would have.

No one fighter was good at everything. There is a bit of a paper / scissors / rock aspect to fighter design.

You declaim the use of rear fuselage tanks on the Spitfire even when you have the data presented to you that the Mustang had exactly the same cautions whilst using the rear fuselage tank, yet they seemed do well in combat. The Spitfire VII/VIII had integral wing tanks as part of the design. Without the fuselage tank the Mustang carried only ~28IG more internal fuel than an Spitfire VII.

The 90IG ST caused a loss of 20mph on a Spit14 and the 30IG tank caused a loss of 14mph on a Spit9 and I'd guesstimate that the 45IG tank would cause a loss of about 15-16mph on a Spit9. This is less speed loss than with the twin DTs on a Mustang or Spit9 which must be released when in contact with enemy fighters, as the STs are fully stressed for combat manoeuvre. You do seem to argue for the sake of it rather than simply admitting that the ST had some advantages over a DT and that the loss of performance was small, in exchange for the ability to carry the fight to the enemy. I suspect that if LR escort Mustang pilots were offered another 90IG of fuel in exchange for a temporary loss of 20MPH that they would have happily used the slipper tank if it was technically feasible.

 

[Schweik]

They did both have wing tanks, true...

As for arguing - it takes two to tango, or in this case more than two - I am hardly the only one here who disagrees with you mate. There are about three others posting in this thread not to mention the historical record which also defies your theory.

Both the Spitfire and Mustang have trouble flying with a full rear fuselage tank. The difference is that the Spitfire also needs to have a slipper tank and probably external wing tanks to get to the target, fight and fly back to base, whereas the Mustang can get there with drop tanks, using up the rear fuel tank and drop-tank gas on the way. And fly home on internal fuel (from the wing tanks). The Mustang can also keep up a much higher cruise speed both there and back.

Fighting with a slipper tank on I suspect causes more than a 15-20 mph speed loss - there would also be impact to climb, acceleration etc.. Even if speed was the only effect, I do not agree that Mustang pilots would choose an extra 90 gallons of fuel for a 20 mph speed loss. Speed was the only real advantage they had and was the trait their tactics depended on most. Mustangs were (usually) faster than their opponents and this enabled them to disengage. For the Spit it was more complicated. The Spitfire turned better and was generally more maneuverable, but speed was comparable or a little less than Fw 190 or late model 109, depending on variants of course. When close to parity on performance Spitfires had the edge.

But we know from the historical record if the Spitfire's performance dropped below a certain threshold compared to the 109 or (especially) the Fw 190, they suffered severe losses. Speed is life in air combat, and apparently in the mix of tactics used by the two (three) aircraft types, the Spit pilot very much needed his airplane to be within striking distance performance wise. In 1943 or later that meant the performance of a Spit IX, Spit VIII, or later mark... not a Spit VB or a Fulmar.

So I guess a big part of our debate hinges on precisely how much of a 'drag' (pun intended) the famous 'slipper tank' really was in combat. We do know that some aircraft scored victories with them still attached, and we know also that some were lost with these attached. Kevin mentioned something about 110s vs Spits but I couldn't find it. Probably more detail on this point might help us put this to rest, unless someone is arguing for the sake of it...

 

[Dan Fahey]

Side note here...!
The combatants all designed Combat planes suitable for their combat terrains.
US and Japanese aircraft built with long range considerations.
Japan because of China, Korea and Pacific Ocean.
USA with a large continent and two oceans.

Europe thought in terms of the next country, including Russia..!
Planes tended short ranged though lighter and slightly more maneuverable.
Heck they fought each other for centuries.
Few considered another far away country could support a war from long distances.

Had the British relied on the Spitfire as a prime fighter they would have lost the war quickly.
It was a tough plane to build using fitment technology vs mass manufacturing.
Much like the Watch Maker Rolls Royce Merlin's...and a lousy engine as far as durability.

It was an outstanding aircraft but every plane builder could turn out 3 combat planes for every Spitfire.
Except for maybe the P-38 Lighting but it was a bomber sized fighter.

Three Hurricanes will shoot down one Spitfire in combat.
The Spitfire was never that much better than any other combat fighter aircraft.

I stressed this before...range and ability to hit at your opponent effectively from a distance was the winning formula.
All the combat planes had useful performance even if they were a generation younger than their opponent.
Late war Zero with seasoned pilots proved that fighting against British and US carrier group fighters off the coast of Japan.

Cost effectively and Performance wise the Mustang was the best most effective & versatile fighter in WW2.
IMHO should have developed the A and B/C/D Mustangs at the same time.
Would have filled a huge performance envelop.

The Mustang was used in every role including Bomber.
Lighten up became an interceptor !
You (Shoulda Coulda Woulda ) put the H-Tail on it and made a fine Carrier plane too.

WW2 was a short war that required everything built to be fault free quickly.
The unsung players of the war were the Engineers, Designers and Testers, some to their demise !

For all the wind about the Spitfire..
IMHO it was a bit player compared to other Combat Aircraft.

D

 

[Schweik]

I don't agree about the Spitfire, there was a need in the war for different combat types. Not every aircraft could be a generalist. You needed escort planes and fighter-bombers and carrier fighters and you definitely needed interceptors especially early in the war. The Spitfire was the only fighter in the Allied arsenal through 1943 that could reasonably be claimed to be as good as, or arguably better than the German fighters. That mattered. And for the Battle of Britain I think you did need a purpose-built interceptor. Casualties were high enough as it is, the British could not have afforded three times more casualties.

The Rolls Royce Merlin was probably the best inline engine of the war, in my book. Only close comparison was the DB 600 series.

After all, it was the engine in the Mustang right?

 

[Schweik]

Also they built ~20,000 Spitfires during the war so they must have figured out the demanding production requirements ...

 

[RCAFson]

T
Both the Spitfire and Mustang have trouble flying with a full rear fuselage tank. The difference is that the Spitfire also needs to have a slipper tank and probably external wing tanks to get to the target, fight and fly back to base, whereas the Mustang can get there with drop tanks, using up the rear fuel tank and drop-tank gas on the way. And fly home on internal fuel (from the wing tanks). The Mustang can also keep up a much higher cruise speed both there and back.

Fighting with a slipper tank on I suspect causes more than a 15-20 mph speed loss - there would also be impact to climb, acceleration etc.. Even if speed was the only effect, I do not agree that Mustang pilots would choose an extra 90 gallons of fuel for a 20 mph speed loss. Speed was the only real advantage they had and was the trait their tactics depended on most. Mustangs were (usually) faster than their opponents and this enabled them to disengage. For the Spit it was more complicated. The Spitfire turned better and was generally more maneuverable, but speed was comparable or a little less than Fw 190 or late model 109, depending on variants of course. When close to parity on performance Spitfires had the edge.

Total internal fuel on a Mustang was 221IG including all internal fuel tanks. Total internal fuel on a Mk VII/VIII with the rear fuselage tank was 200IG.

I earlier presented the data from a Spitfire IX with a 30IG slipper tank and here's a link to the full report:

Spitfire F Mk IX BF274 Test

Maximum speed drops from 404mph to 389mph. Time to climb to 20K ft increases by 30secs using normal climb power. As this report was being written boost levels were increased and maximum speed increased to 409mph.

This is from the report on the Mk XIV with a 90IG ST:

The account below is taken from the report of the tactical trial
of an early production Mark XIV, RB 179, flown by the Air
Fighting Development Unit at Wittering in February and March
1944.

Combat Performance with 90 Gallon Long-Range Tank

As the Spitfire XIV has a very short range it has been
assumed that when a long-range tank is to be carried, it is
most likely to be the 90 gallon tank rather than the 30 gallon or
45 gallon. Pending further instructions, no drops or trials have
been carried out with the 30 gallon or 45 gallon tanks. The
aircraft's performance with either can be estimated from the
results given below of trials with the 90 gallon long-range
tank.

Drops
The aircraft was fitted with assistor springs as for the
Spitfire IX. Two drops were made with empty tanks at 50 ft
and 25,000 ft, ASI 250 mph. with no trouble. Cine photo-
graphs were taken and show the tank dropping quite clear of
the aircraft. Further trials would be necessary to check these
results thoroughly.

Speeds
About 20 mph is knocked off the maximum speed and
correspondingly off the speed at intermediate throttle set-
tings. The aircraft is then still faster than the FW 190 (BMW
801D) and the Me 109G above 20,000 feet.

Climb
Climb is most affected. With a half-full tank its maximum
climb becomes identical with the Spitfire IX without the tank.
Even with a full tank it can therefore climb as fast as the
FW 190 or Me 109G. Its zoom climb is hardly affected.
Dive

So long as the tank is more than 1/3 full, the dive accelera-
tion is similar.

Turning Circle
The Spitfire XIV now has a definitely wider turning circle
than before, but is still within those of the FW 190 (BMW
801D) and Me 109G.
Rate of Roll
Similar.

Conclusions

Even with the 90 gallon long-range tank, the Spitfire XIV
can equal or outclass the FW 190 (BMW 8010) and Me 109G
in every respect. Its main advantages remain the right turn
and maximum climb.
(Price, The Spitfire Story)

Depending on the opponent, the Mustang typically had more than a 40mph edge at high altitude (being the same speed as a Mk XIV) and losing 20mph in exchange for increased endurance equal to 35mins at full WEP seems like a fair trade.

 

[Schweik]

"As the Spitfire XIV has a very short range it has been
assumed that when a long-range tank is to be carried, it is
most likely to be the 90 gallon tank rather than the 30 gallon or
45 gallon. "

Sounds like they must be talking about a different fighter than you have been eh? Very short range? Did they read all those reports?

The first series of tests you linked are for effects with a 30 gallon tank, and those are bad enough, showing a clear decline in performance

The above points out you needed a lot more fuel to make it a viable long range fighter, so 90 gallons is more likely.

Even the 30 gallon tanks drops the top speed for that Spit IX is down to 389 at 30,000 ft, and 365 mph at 20,000 ft which is getting close to Spit V performance I'd say... and there was a corresponding decline in speed at lower power settings.

The report on the Spit XIV + 90 gal tank sounds like the 90 gal tank affects turning circle, climb, and acceleration. I'd sure bet stability as well. Still, it patriotically insists that this is still way better than a Fw 190 or Bf 109G, and maybe it is for specific versions, but peers of the Spit XIV included the Fw 190D-9 and the 109G-10 and 109K. Both I think are going to have a substantial performance edge over the older type Fw 190 and 109G. Bf 109K-4 is making 440 mph at WEP at 24,000 ft and an initial climb rate of 4,822 fpm. Spit XIV seems to have a slight performance edge even over the K-4 under normal flight conditions but with a 20 mph speed hit that would go away.

You need to bring your "A game" to handle the oppo that late in the war.

 

[BiffF15]

Total internal fuel on a Mustang was 221IG including all internal fuel tanks. Total internal fuel on a Mk VII/VIII with the rear fuselage tank was 200IG.

I earlier presented the data from a Spitfire IX with a 30IG slipper tank and here's a link to the full report:

Spitfire F Mk IX BF274 Test

Maximum speed drops from 404mph to 389mph. Time to climb to 20K ft increases by 30secs using normal climb power. As this report was being written boost levels were increased and maximum speed increased to 409mph.

This is from the report on the Mk XIV with a 90IG ST:



Depending on the opponent, the Mustang typically had more than a 40mph edge at high altitude (being the same speed as a Mk XIV) and losing 20mph in exchange for increased endurance equal to 35mins at full WEP seems like a fair trade.

RCAFson,

Adding a 90IG ST to a MkXIV will also add drag. Yes you get more fuel, but how much range do you really get after the increased drag is taken into account, and at escort speeds?

Cheers,
Biff

 

[Schweik]

Just to explore the speeds a bit further...

this shows Spit IX, Fw 190 A-5, A-3, and G-3, as well as a P-47 and some others for comparison.

Spit IX peaks at ~ 407 mph at about 22,000 feet and maintains close to that through 26,000

Fw 190A-5 peaks at ~ 410 mph at about 21,000 ft which drops below 400 at 23,000

So they have comparable speed, Fw has the fast roll rate and dive, Spit IX has a bit better altitude performance, climb and turns better etc. so it has an advantage.

The speeds on the charts you posted show slightly inferior performance (before slipper tank) for the Spit IX of 402 mph with 15.2 lbs boost at 27,400 ft and 380 mph at 20,000 ft. down to 15,000 ft.

With the 30 gal slipper tank, you get a 19 mph drop in top speed and a 15mph drop in speed at 20,000 ft. That is again, like I said putting it very close to Spit V performance, in fact it's a bit slower than test data for example here showing 372 mph at 20,000 ft for a Spit V, declining to 364 at 25,000 ft. In part, the Spit V suffered from declining performance at higher altitudes, which the two stage engine on the Spit IX largely alleviates, but it's worth pointing out that at that crucial height of 15-20k, where so many of the British bombers were cruising, you have turned your thoroughbred Spit IX back into a Spit V.

At 20,000 ft the Spit IX with the 30 gallon tank* has a 45 mph speed disadvantage against a Fw 190A-5. I say that spells doom, based on prior history.

(*not even the 90 gallon tank which per your report was probably more realistic)

Of course if they were unlucky enough to run into a Fw 190D-9 it's even worse.

 

[pinsog]

.

 

[RCAFson]

RCAFson,

Adding a 90IG ST to a MkXIV will also add drag. Yes you get more fuel, but how much range do you really get after the increased drag is taken into account, and at escort speeds?

Cheers,
Biff

At the same throttle setting speed is reduced by about 20mph TAS, so at full power this would result in a ~5% decrease in range, compared to an additional 90IG internal fuel, and maybe ~7% at Max weak mixture and ~9% at Most economical,.

For reference this is the effect of a 90IG ST on the MkV Trop:

SpitV trop without / with 90IG ST
Time to 20,000ft 8 mins / 10 mins
Max speed @ 17,400ft 354mph / 337.5
20K ft economical range 600 / 1230miles (unclear if with allowance for TO and climb)
(M&S)

 

[pinsog]

Wow that's dark! No wonder all the revolutions so soon after the war.... I know Malaya went into a revolt very soon after right?



Didn't know that! Different engine variant I guess? RN / Fleet Air Arm seemed to have a preference for low altitude engines for so many of their planes which I never did grasp. They must have had the strangest procurement policies of the war and that is saying something.

Well, FM-2s then the US had plenty of those I think.

I may be wrong, but I believe the reason the British got 2 speed engines in the Martlet instead of the 2 stage engine the Wildcat had was due to there not being enough 2 stage engines available, not because that's what the British wanted.

 

[RCAFson]

"As the Spitfire XIV has a very short range it has been
assumed that when a long-range tank is to be carried, it is
most likely to be the 90 gallon tank rather than the 30 gallon or
45 gallon. "

Sounds like they must be talking about a different fighter than you have been eh? Very short range? Did they read all those reports?

The first series of tests you linked are for effects with a 30 gallon tank, and those are bad enough, showing a clear decline in performance

The above points out you needed a lot more fuel to make it a viable long range fighter, so 90 gallons is more likely.

Even the 30 gallon tanks drops the top speed for that Spit IX is down to 389 at 30,000 ft, and 365 mph at 20,000 ft which is getting close to Spit V performance I'd say... and there was a corresponding decline in speed at lower power settings.

The report on the Spit XIV + 90 gal tank sounds like the 90 gal tank affects turning circle, climb, and acceleration. I'd sure bet stability as well. Still, it patriotically insists that this is still way better than a Fw 190 or Bf 109G, and maybe it is for specific versions, but peers of the Spit XIV included the Fw 190D-9 and the 109G-10 and 109K. Both I think are going to have a substantial performance edge over the older type Fw 190 and 109G. Bf 109K-4 is making 440 mph at WEP at 24,000 ft and an initial climb rate of 4,822 fpm. Spit XIV seems to have a slight performance edge even over the K-4 under normal flight conditions but with a 20 mph speed hit that would go away.

You need to bring your "A game" to handle the oppo that late in the war.

Are you interested in a serious discussion or just in making snide comments? The RAF knew full well that a Griffon Spitfire was short on range, which is why they developed a method of adding 90IG of external fuel that could be retained in combat (or not at the pilot's discretion), with only a minimal reduction in performance. Again, the Spit XIV proved superior to the 190 and 109 even with the 90IG ST and we are talking about mid 1943 not mid 1945. The thing to take away from this is that a Spitfire VIII with a 45IG ST is still going to compare well against the Luftwaffe in mid 1943 and while any escort fighter is better than none, a MKVIII with a 30/45IG ST is still a formidable aircraft in Mid 1943.

The Spit IX is going to be able to run at full overboost for 12/18mins with the 30 / 45IG tank, versus how long for the FW190A/109G? The small reduction in speed is balanced by the ability to use higher power, and as I stated earlier actual maximum speeds would be about 5mph faster so about 394 at 27400ft and 370 at 20K ft and again as I stated earlier Luftwaffe Reich defence fighters often carried DTs and/or extra ordnance so, in mid 1943, the numbers for the MK VIII/IX are still pretty good even with the ST attached.

 

[RCAFson]

I may be wrong, but I believe the reason the British got 2 speed engines in the Martlet instead of the 2 stage engine the Wildcat had was due to there not being enough 2 stage engines available, not because that's what the British wanted.

The FAA specified single stage engines because they were lighter and more efficient at low altitude.
The F4F-4B weighed about 300lb less than the -4 and a USN comparative trial stated "...the difference in performance was very small, the F4F-4B being slightly superior in speed and climb at low altitudes and the F4F-4 slightly superior at 15000ft and above..."

 

[pinsog]

The FAA specified single stage engines because they were lighter and more efficient at low altitude.
The F4F-4B weighed about 300lb less than the -4 and a USN comparative trial stated "...the difference in performance was very small, the F4F-4B being slightly superior in speed and climb at low altitudes and the F4F-4 slightly superior at 15000ft and above..."

Apparently I was wrong. Thank you for the correction

 

[RCAFson]

Just to explore the speeds a bit further...



With the 30 gal slipper tank, you get a 19 mph drop in top speed and a 15mph drop in speed at 20,000 ft.

The test data showed a 14mph drop in Vmax and a 10mph drop at 20k ft (15mph using lower gear or stage). You've read the data incorrectly as there are dual entries for some altitudes that are close to the supercharger gear and stage changes.

For reference a Mk VII HF was about 10mph faster than the MK IX F:

20k ft 400mph
26k ft 412mph
29.4k ft 424mph
(Price)

 

[PAT303]

I looked at them, several of them have Spit XIVs with 90 gallon tanks flying about 2 hours give or take from take-off to landing. While quite useful it is hardly in the same league as flying to Schweinfurt is it?
The first one posted has a victory near the French town of Fleche is roughly the same distance as Paris depending on where in England you take off from.

There is no doubt that the 90 gallon tanks were used on operations, however the 90 gallon tank alone (or better said, in conjunction with standard fuselage tanks) does not give the needed range for missions much past the Rhine.

How far do they need to go?, no one is saying the Spit can match the P51 but if set up like this http://www.spitfireperformance.com/spitfire9-fuelsystem-lr.jpg they could cover a lot of territory.