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

[Greyman]

From wiki:

By mid-1944, the Allied air forces enjoyed undisputed air supremacy over Burma. The last major effort by the Japanese Army Air Force had been over the Arakan in February and March, when they had suffered severe losses. During the Imphal and Kohima battles, they were able to make barely half a dozen significant raids.

 

[Kevin J]

I wanna check only one, was RAF able to maintain air superiority in the battle of Imphal?
I know that it was in the middle of the allied counterattack, but at the same time it was also the last offensive oparation of the CBI theater by the Japanese army.So, I think that it is very important which one has air superiority at that time.

Yes they did.
Battle of Imphal - Wikipedia
Battle of Kohima - Wikipedia
RAF Third Tactical Air Force - Wikipedia

 

[UnderPressure]

Thanks guys. I didn't think RAF had such a great air superiority while doing large scale transportation. they were dispatching Spitfires, which had been deployed only a little, to escort Dakotas...

 

[Kevin J]

Thanks guys. I didn't think RAF had such a great air superiority while doing large scale transportation. they were dispatching Spitfires, which had been deployed only a little, to escort Dakotas...

I think you'll find they had 3 squadrons of Spitfire VIII's available at the time, a plane totally superior to its JAAF opponents. I don't think they would have had any problems at all undertaking the escorts.

 

[UnderPressure]

Sorry for my english is not quite up to native level...

I think you'll find they had 3 squadrons of Spitfire VIII's available at the time

AFAIK, At that time 615sqn operated Mk.V in part and They used Mk.V even in the Air combat of June 17. Maybe, 81 and 136 sqn were running Mk.VIII then.

a plane totally superior to its JAAF opponents.

By my count, 9 Mk.VIIIs were lost, four of them were destroyed on the ground. On the other hand, nearly 20 Ki-43s were shot down by Spitfires. Therefore, I agree that Spitfire is definitely superior to Ki-43.

However, what I'm worried about is the amount of spitfire that could cover or patrol. I think remaining squadrons are too few to defend Burma.

 

[Wawny]

The Spitfire performance numbers you post from the Wawn and Jackson trials match up well with a tropical Spitfire Vc running +9 boost/3000 rpm. It appears they weren't 'pulling the tit' and using +16 boost.

Maybe that ability wasn't available in Austrailia, I have no idea. Perhaps there is a note why in the original document.

My dad was the Spitfire pilot against the Hap and he bent the tail of the Spitfire 15 degrees (Dad's annotation) doing some pretty evasive 'high G' manoeuvering.
He also flew a Kittyhawk against a Spitfire at Mildura during tests - parameters attached.
In both cases the Volkes Filter diminished the performance considerably, especially in the tropics. He reckoned if he wasn't wearing (and testing) the Cotton G Suit, he couldn't have pulled the G's that he did

 

[Schweik]

Wow this is quite interesting. I'm surprised the Kittyhawk was accelerating faster than the Spit V and had a higher top speed below 16,000 ft. Sounds like the Vokes filter was a real disaster. I wonder if the Kitty pilots were overboosting.

"5. Results:
a) Spitfire had the greater rate of climb at all heights - the difference becoming greater as height increased above 13,000ft.

b) Spitfire is far more manoeuvrable at all heights.

c) Kittyhawk is faster in level speed from 0 to 16,000ft. Above 16,000ft Spitfire is faster and again the difference becomes greater as height increases. Estimated speed advantage of Kittyhawk up to 16,000ft: 0ft - 15mph; 12,000ft - 20 to 25mph; 16,000ft - 5 to 10mph.

d) Kittyhawk accelerates, both in dive and on increase of throttle on the level, far more quickly than the Spitfire.

6) Combat 1 - commenced at 13,000ft (equal height) and lasted for 5 to 7 minutes, in which time the fight was practically a stalemate. At the end of this period height was reduced to 4,000ft when the Kittyhawk pilots decided he had nothing to gain by staying and so broke off by diving away. Thus, in combat up to 16,000ft, the Kittyhawk has the distinct advantage in that the pilot can commence the fight and discontinue it at will. In such a combat the Kittyhawks tactics are to hit and run, and then come again.

7) Combat 2 - commenced at 20,000ft (equal height) and lasted less than 2 minutes. Spitfire quickly gained dominant position on the tail of the Kittyhawk and couldn't be shaken. Kittyhawk pilot broke off by diving away.

8) Combat 3 - Commenced at 16,000ft (height advantage to Kittyhawk) an lasted 14 minutes. Kittyhawk made repeated dive and zoom attacks with the Spitfire alternatively breaking hard to avoid and climbing for advantage where possible. Fight reduced to 9,000ft with neither pilot gaining a decisive advantage.

9) Combat 4 - Commence at 16,000ft (height advantage to Spitfire) and lasted 11 minutes. Spitfire pounced on Kittyhawk and attempted to gain a position on tail. Kittyhawk used speed advantage in first level flight and then shallow dive to gain separation and then climb for advantage. Spitfire countered by climbing hard. Gaining advantage Spitfire used climb and dive tactics to force the Kittyhawk to make repeated diving breaks to avoid. At 7,000ft Kittyhawk used superior roll rate to scissor behind the Spitfire, who countered with steep climb. Kittyhawk then used speed advantage to again gain separation and fight was broken off.

10) Visions - the vision in the Spitfire with the hood closed is better than the Kittyhawk, but it is a definite disadvantage that the hood cannot be opened at speeds above 160mph particularly when searching up-sun.

11) The flying characteristics of the Spitfire make it more suitable for Operations:

a) it is easier to fly.

b) Take-off run is much shorter and so could be operated from smaller landing grounds. Note – the Spitfire does not handle hard dirt strips as well as the Kittyhawk.

c) Mixture and boost are automatically controlled.

d) It is not necessary, as it is in the Kittyhawk, to alter rudder and elevator trims over great speed changes.

All these facts greatly reduce the pilot's problems and so increase his fighting efficiency. The report concluded by recommending that as the large Volkes air filter on the Spitfire cost 20-30mph in top speed, it should be removed in operational service - or at least an alternative found. Also mentioned was the effect of the Spitfires rough paint finish on performance but the general feeling of the report was that the Spitfire was perhaps the better fighter, especially at altitude."

 

[Kevin J]

Wow this is quite interesting. I'm surprised the Kittyhawk was accelerating faster than the Spit V and had a higher top speed below 16,000 ft. Sounds like the Vokes filter was a real disaster. I wonder if the Kitty pilots were overboosting.

"5. Results:
a) Spitfire had the greater rate of climb at all heights - the difference becoming greater as height increased above 13,000ft.

b) Spitfire is far more manoeuvrable at all heights.

c) Kittyhawk is faster in level speed from 0 to 16,000ft. Above 16,000ft Spitfire is faster and again the difference becomes greater as height increases. Estimated speed advantage of Kittyhawk up to 16,000ft: 0ft - 15mph; 12,000ft - 20 to 25mph; 16,000ft - 5 to 10mph.

d) Kittyhawk accelerates, both in dive and on increase of throttle on the level, far more quickly than the Spitfire.

6) Combat 1 - commenced at 13,000ft (equal height) and lasted for 5 to 7 minutes, in which time the fight was practically a stalemate. At the end of this period height was reduced to 4,000ft when the Kittyhawk pilots decided he had nothing to gain by staying and so broke off by diving away. Thus, in combat up to 16,000ft, the Kittyhawk has the distinct advantage in that the pilot can commence the fight and discontinue it at will. In such a combat the Kittyhawks tactics are to hit and run, and then come again.

7) Combat 2 - commenced at 20,000ft (equal height) and lasted less than 2 minutes. Spitfire quickly gained dominant position on the tail of the Kittyhawk and couldn't be shaken. Kittyhawk pilot broke off by diving away.

8) Combat 3 - Commenced at 16,000ft (height advantage to Kittyhawk) an lasted 14 minutes. Kittyhawk made repeated dive and zoom attacks with the Spitfire alternatively breaking hard to avoid and climbing for advantage where possible. Fight reduced to 9,000ft with neither pilot gaining a decisive advantage.

9) Combat 4 - Commence at 16,000ft (height advantage to Spitfire) and lasted 11 minutes. Spitfire pounced on Kittyhawk and attempted to gain a position on tail. Kittyhawk used speed advantage in first level flight and then shallow dive to gain separation and then climb for advantage. Spitfire countered by climbing hard. Gaining advantage Spitfire used climb and dive tactics to force the Kittyhawk to make repeated diving breaks to avoid. At 7,000ft Kittyhawk used superior roll rate to scissor behind the Spitfire, who countered with steep climb. Kittyhawk then used speed advantage to again gain separation and fight was broken off.

10) Visions - the vision in the Spitfire with the hood closed is better than the Kittyhawk, but it is a definite disadvantage that the hood cannot be opened at speeds above 160mph particularly when searching up-sun.

11) The flying characteristics of the Spitfire make it more suitable for Operations:

a) it is easier to fly.

b) Take-off run is much shorter and so could be operated from smaller landing grounds. Note – the Spitfire does not handle hard dirt strips as well as the Kittyhawk.

c) Mixture and boost are automatically controlled.

d) It is not necessary, as it is in the Kittyhawk, to alter rudder and elevator trims over great speed changes.

All these facts greatly reduce the pilot's problems and so increase his fighting efficiency. The report concluded by recommending that as the large Volkes air filter on the Spitfire cost 20-30mph in top speed, it should be removed in operational service - or at least an alternative found. Also mentioned was the effect of the Spitfires rough paint finish on performance but the general feeling of the report was that the Spitfire was perhaps the better fighter, especially at altitude."

So that's why the Tomahawk IIb and Kittyhawk I got sent to the Western Desert in 1941/42 before the Spitfire Vb / Vc Trop. You definitely needed that big Volkes dust filter, and extra oil tank for use with the long range slipper tanks, out there for the Spitfire.

 

[MIflyer]

It seems that the P-40 did have quite good acceleration. Here is what Corky Meyer said about the P-40

"I was on final approach to Grumman's airport in a P-40N that had been loaned to us by the USAAF for comparative testing, and during the test flight I had found it to have very poor slow-speed characteristics. About that time, another test pilot buzzed the field coming under me in the same direction. This was not an unusual occurrence in those days when the war-effort syndrome allowed test pilots to get away with murder when it came to breaking the rules.
Having just found out that the Warhawk had much better power acceleration than the Hellcat, I decided to pull up my wheels and flaps and give him a go at a rat race (which was also covered by the same syndrome).

I pushed the throttle forward and pulled up into a steep fighter climb as the wheels and flaps were retracting. At about 700 feet, my exuberance ended most abruptly when the airplane stalled unexpectedly and violently.

The control stick and rudder pedals flapped loosely around the cockpit, and the airplane snapped back and forth in a roll. Those are the last events I remember coherently. The airplane was shaking violently. It then started into a spin—still shaking like a dog getting rid of a water bath. I could see the hangars with great clarity and with a strange detachment. I was stupefied—mesmerized—and seemed to be sitting on the sidelines watching this unbelievable panorama unfolding. My mind was a blank as to what action I should be taking in this horrible kaleidoscope I was watching as if I didn't have a concern in the world. It just couldn't be happening to me!

The next thing I remember was moving level at 50 feet over the potato fields west of the Grumman airport with the ground whizzing by at a great speed. I was still mentally only riding this P-40. I was not flying it because the maneuver it had just done was completely out of my frame of reference, even in nightmares.
I finally noted that the throttle was pushed through both of the limiting wires, and the engine was straining with much more power than I had heard or felt during takeoff. I was in War Emergency Power. After a few seconds, I came to my senses, retarded the throttle and climbed to 1,500 feet. I turned back rapidly to the airport, as the sun had almost set and it was rapidly getting dark.

Were I a test pilot of greater experience, I might have related in my reminiscence that I calmed down, remembered all the instructions in the handbook about spins, jotted some meaningful notes about the "incident" and made a nonchalant, smooth, three-point landing. I was totally without any of these movie-star proclivities. I was still stupefied. I flew around the airport without calling the tower and talked to myself like a Dutch uncle. I said, "You stupid SOB. You can't land this airplane. You are running out of gas. It is getting dark and you have to land this airplane," etc., etc. My conversation was also sprinkled with four-letter words impugning my legal birthright.

After too many circuits of the field, I humbly called the tower and was given landing clearance. They were charitable and made no embarrassing commentary. I made a long, airline-style approach at a speed considerably higher than required and landed without further ado. I taxied back to the tower, where all the pilots were still gathered. They had seen my spin and wanted to see the color of my face after that farce. After the propeller had stopped rotating, the airplane continued to shake. When it stopped shaking, I did, too, and guessed that I might now be able to stand on my own two feet. I got out to the total silence of the pilot mob watching.
Later, they told me that I made a turn-and-a-half spin, came down below the hangars behind them and scurried out to the west at 50 feet off the ground like a bat out of hell. I had no recollection of the number of turns of that spin until they told me.

That flight was one of the most impressive of my test-pilot career. I learned to listen to airplanes for everything they had to tell me. I became a born-again-Christian immediately after that 30-second episode of my P-40 flight."

 

[Schweik]

Wow that's scary. Yes I would expect a P-40N to accelerate better than a Hellcat, at least at low altitude. It had a better power to weight ratio.

P-40E vs. Spit V is a surprise though unless the former was overboosting and the latter really struggling with the filter. I guess the filter just caused a lot of drag because the filter itself was supposed to be bypassed after takeoff right?

 

[Greyman]

Wow this is quite interesting. I'm surprised the Kittyhawk was accelerating faster than the Spit V and had a higher top speed below 16,000 ft. Sounds like the Vokes filter was a real disaster. I wonder if the Kitty pilots were overboosting.

If the Kittyhawk is 15-20 mph faster up to 16,000 ft that matches up well with a P-40 running the regular 42-inch boost and 3000 rpm vs. a tropical Spit V running 9-lb boost at 3000 rpm.

 

[Schweik]

Even at 9 lbs , Spit V Trop should still have a very high power-to weight ratio, better than the Kitty I would think? When was 12 lbs introduced?

It's interesting that they mention the challenges on the Kittyhawk of changing rudder trim settings during rapid speed change, and note that the Spit is easier to fly, but it doesn't seem to cause the Kittyhawk pilot to perform worse in the dogfights, to the contrary it seems to be able to contend with the Spit even when in a height disadvantage via scissors and is able to dive away at will.

How do you feel this translates to a match up against a Bf 109E7 or F2? How does the Bf 109 dive compare to the Spit V

 

[Greyman]

+12 was there from the start. Again we're kind of puzzled why +12/+16 doesn't appear to be used in Australia.

An easier plane to fly is always a plus, and being able to escape at will is a very nice option to have, but in these mock combats it doesn't appear that the Spitfire--unlike the Kittyhawk--ever needed to escape.

The 109F had a notable dive advantage on the Spitfire V.

 

[BiffF15]

Don't forget the variables of pilots. They may be close in skill, or one may be more proficient in his steed than the other. Difficult airplanes can be mastered, a pilot can have a better day than the next guy, the list goes on. Multiple pilots over multiple days with multiple set ups would be optimal, but in the middle of a war one takes what one can get.

Cheers,
Biff

 

[GrauGeist]

Don't forget the variables of pilots. They may be close in skill, or one may be more proficient in his steed than the other. Difficult airplanes can be mastered, a pilot can have a better day than the next guy, the list goes on. Multiple pilots over multiple days with multiple set ups would be optimal, but in the middle of a war one takes what one can get.

Cheers,
Biff

There was also the occasional hangover that *may* have been a contributing factor to a pilot's abilities if they've been roused out of the rack during an early morning scramble, too.

 

[Schweik]

+12 was there from the start. Again we're kind of puzzled why +12/+16 doesn't appear to be used in Australia.

An easier plane to fly is always a plus, and being able to escape at will is a very nice option to have, but in these mock combats it doesn't appear that the Spitfire--unlike the Kittyhawk--ever needed to escape.

Well that is just turn and burn vs. boom and zoom, just like when a P-40 would be fighting a Zero, the BnZ plane usually has an edge though certainly not always, and it depends by how much of a speed / dive advantage it had. But this does say pretty definitively that a P-40E could out-dive the Spit V, at least at the boost ratings they were using and with the Vokes filter. At +12 I don't know, though we don't know if the P-40E was using high boost settings either...

The 109F had a notable dive advantage on the Spitfire V.

The report language is a bit ambiguous but it sounds to me like they were saying in combats 2 and 3 that the P-40 was getting on the tail of / or making attacks against the Spit. Unclear if that means a "firing solution" but it sounds like it does. Combat 1 was 'practically' a stalemate with the P-40 able to make hit and run attacks. Combat 4 up at 20,000 ft clearly went to the Spit.

If this was the results of a Spit V (Trop) vs. P-40E, i.e. roughly even overall up to 16,0000 ft, with a speed advantage to the P-40, presumably this is how the other P-40 variants used in the Med should shape up:

P-40E - Takeoff power 1,240 hp @ 45" Hg, WEP 1,470 hp - power / weight 0.14 at military, 0.17 at WEP (sea level) critical altitude ~ 12,000 ft
P-40K - Takeoff power 1,325 hp @ 51" Hg, WEP 1,550 hp - power / weight 0.16 at military, 0.18 at WEP (sea level) critical altitude ~ 12,000 ft
P-40M - Takeoff power 1,200 hp @ 45" Hg WEP 1,300 hp - power / weight 0.13 at military, 0.15 at WEP (~8,000 ft) critical altitude ~ 16,000 ft
P-40F - Takeoff power 1,300 hp @ 50" Hg, WEP 1,435 hp - power / weight 0.15 at military, 0.16 at WEP (at 11,800 ft and 18,500 ft*) critical altitude ~ 20,000 ft
P-40L** - Takeoff power 1,300 hp @ 50" Hg, WEP 1435 hp - power / weight 0.16 at military, 0.17 at WEP (at 11,800 ft and 18,500 ft) critical altitude ~ 20,000 ft (maybe a bit more)

P-40K should be substantially better than the P-40E against the Spitfire particularly at low altitude (say below 3,000 ft)
P-40M should be similar to the E but equal to the Spit up to a little bit higher altitude, maybe 18,000 ft
P-40F should be a bit better at all altitudes up to maybe 22,000 ft
P-40L** should be substantially better up to ~22,000 ft

All versions should be able to out turn and out roll the Bf 109F or G up to their critical altitude.

P-40N's were also used in the Med in Italy and the Balkans, by the British, but I think almost exclusively for fighter-bomber sorties so I didn't include it.

* I have to admit I don't understand precisely where the Merlin 28 / XX reaches it's two highest power output points, one source said 6,000' for low gear so maybe SR8 can clear that up
** This would also be the same for field stripped, 4 gun P-40Fs

 

[MIflyer]

The P-40F had a two speed supercharger, so speed increased to 11,500 ft, at which point it would have dropped off, but the 2nd speed of the supercharger kicked in and the speed increased up to 20,000 ft, after which it dropped off. At 20,000 ft the F was over 30mph faster than the E model, but the E model was around 10 mph faster than the F at sea level. The P-40F had about the same climb rate as the K model until about 15,000 ft where the F started increasingly climbing faster.

The P-40N-5 and -40 was actually slower than the E or F but climbed quite a bit faster over over 10,000 ft.

The F was heaver than the others due to the Merlin engine's greater weight so it probably was not as quite as maneuverable.

 

[Schweik]

Yeah I know about the two speeds, but I wasn't sure which two altitudes were critical.

The P-40F of course was habitually stripped down to 4 guns and had one of the fuel tanks removed and some other stuff. The P-40L (same as the stripped P-40F configuration) had a slightly lower empty weight than the E. This wasn't so much for maneuverability though as for performance at altitude and climb rate. The L had an initial climb rate of 3,300 ft/min which is much better than all the other P-40 models.

 

[Shortround6]

Yeah I know about the two speeds, but I wasn't sure which two altitudes were critical.

They both were.
The lower one is wide open throttle in low supercharger gear and the upper one is wide open (Full Throttle Height/FTH) in high gear.
Full throttle height is just another term for critical altitude.

 

[Schweik]

They both were.
The lower one is wide open throttle in low supercharger gear and the upper one is wide open (Full Throttle Height/FTH) in high gear.
Full throttle height is just another term for critical altitude.

Right, what I meant is that I saw two sets of numbers, one 6,000 / 12,000 and the other 11,000 / 18500 or thereabouts.