The real combat history of the Ki-43 (1 Viewer)

[Holtzauge]

This is correct as many times the manuals or listed stall speeds are for the plane in "landing configuration" with flaps and landing gear down. Possibly useful if you are comparing one to another plane that use the same flap type/system and use flaps of the same size. If they don't use similar flaps comparing land stall speed doesn't tell you much about stall speed in a high speed turn.
Sometimes you can find the stall speed with flaps and landing gear up which is much better but in some cases (like Ki 43 to Spitfire) it doesn't work as the Spitfire cannot use it's flaps in combat the Ki 43 famously can. However the Ki-43 does not use the landing position of the flap in combat. It extends the flap and lowers it about 8 degrees which is nowhere near the landing setting. Spitfire flap does very little for lift and is pretty much an airbrake to create drag and steepen the glide path.

Sometimes stall speed for both flaps up and flaps down is given: For the Spitfire Mk I in the June 1940 edition 1565A of the flight manual it says 69 mph flaps up and 63 mph flaps down (IAS). And yes, the straight and level stall speed does not say much about things like g-loaded sustained turn rate and which is why Clmax, wing area and wing span is a better way to compare turn performance. Regarding flaps, the RAE actually did a report for the Spitfire's turn performance in which they concluded as you say that it does create a lot of drag. But even so they also concluded that the split flap in landing configuration did improve turn performance (especially shorter radius) as well. But if the Ki 43 could drop combat flaps then that certainly must have been an asset.

Spitfire Mk I N.3171 Trials Report

Spitfire Performance Testing, wartime flight trials and reports of Spitfire aircraft. Spitfire Mk I data.

www.spitfireperformance.com

Lists several stalling speeds and either does not say TAS when it is TAS or says ASI when it is ASI?

In conjunction to the stall speeds given in that report (78 and 68 mph respectively for flaps up flaps down) the other numbers are IAS which makes sense since otherwise they would need to state stall speed with altitude. In addition, those values also highlight the unreliable nature of stall speed numbers since they are different than from the 1565A flight manual, maybe due to a different all-up weights and/or speed indicators being used.

 

[SaparotRob]

I'd normally bow to your greater knowledge but after checking the potted 261 history by Shores et al in "Malta, the Hurricane Years" it seems that we've each got it partly right. Shores says that 261 was disbanded in Malta in May 1941 with most of the pilots dispersing, some going to 249, some going to 127, and others elsewhere. Shores says that "a handful" of ex-Malta pilots went into the reformed 261 that was created in Iraq.

In the BBM database of pilots it's noted that F O N. Doughty was 'sent to Takali airfield for use by 261 Squadron in the defence of Malta. Doughty, however, only stayed until 6th July when he was posted to 127 squadron at Kasfareet in Syria flying Hurricanes…..On 12th of July, 127 squadron was absorbed into 261, Doughty rejoining his old unit on the 17th by flying six Hurricanes from Deir Ez Zor to Habbaniya." It is also stated that he joined the "reformed 261 as flight commander…..". My emphasis.

There's a personal account on Fl Lt Pickering of 261 which refers clearly to the squadrom's "departure from Malta in about June 1941" on p. 409 of Shores et el - not disbanding. He refers to the need to alter tactics when fighting the Italian aircraft compared to when fighting 109s in the BoB and also that later experience in the Far East showed how tactics had to be altered for local conditions- something which was too often ignored. Pickering, together with fellow ex-261 pilot Len Davies, certainly flew in Burma - see Bloody Shambles Pt 3 p 372.

Birtles on p. 146 of "Hurricane: the illustrated history" says that in late May '41 261 (which had been a very big squadron earlier in Malta) was relieved by 249 Squadron. 261 was "relocating to the Middle East" (again, not being disbanded) and took 249's new Hurries, leaving 249 with old planes and no kit.

The carriers that flew off 249 are said to have flown off 48 Hurries in 3 squadrons although Birtles doesn't give a number on how many 249 had. All of 249's planes made it so we could possible assume they had 16+ Hurries that 261 took. When 185 was formed to go alongside 261 Birtles says there were 50 Hurries on the island, with 10 lost by the time 249 came.

Since 185 was formed from a nucleus of 261 it's probably quite likely that 261 had at least 25 Hurries (50% of the force) when the new squadron was formed and 20 when 249 arrived. So according to Birtles only some of 261's survivors were formed into 185 and 16 or so ex-249 Hurries were flown by 261 to their new home in "the Middle East" when 261 was "relocating".

So from Shores et al, Pickering (a first-hand source) and Brtles, it appears that some of 261's pilots went to 249 together with 261's old planes. The other 261 pilots flew out of Malta and the squadron was disbanded for a while but reformed with several of the earlier Malta pilots. Perhaps the "disbanding" was a planned bureaucratic way to clear the decks and do some pilots selection and reorganisation, give exhausted pilots a change of scenery or at least a rest, and then re-form 261 around a nucleus of old hands?

Some of these ex- "Malta 261" hands and other Malta pilots formed a reasonable proportion of the Far Eastern RAF in the early Pacific War. Shores et al's potted bios of Malta pilots also shows that about a dozen of them flew in Burma and Sri Lanka about that time. We know that least one (Pickering) specifically noted that the RAF had to change tactics to match the Italian aircraft and also to match the conditions in Burma, and that some pilots did so. We know that this was done by February 1942.

So we know from a very good source, or three, that a significant bunch of ex-Malta pilots were in Burma and Sri Lanka at the time; we know that some of them dropped the old "Battle of Britain" tactics and adopted new ones to suit the characteristics of Japanese aircraft quickly; and we know that some of them knew this sort of flexibility was required. That seems to add up to making it pretty clear that the RAF pilots were not slow-learners wedded to tactics that had worked against 110s and 109s - they were intelligent, aware of the need to change the tactics to meet the situation, and did so quickly.

I'd also live to give this post an "informative" too.

 

[MiTasol]

Regarding flaps, the RAE actually did a report for the Spitfire's turn performance in which they concluded as you say that it does create a lot of drag. But even so they also concluded that the split flap in landing configuration did improve turn performance (especially shorter radius) as well. But if the Ki 43 could drop combat flaps then that certainly must have been an asset.

The Spitfire flaps are pnuematic through small plumbing making them slow to move.

The Ki-43 ones were hydraulic through a rack and pinion making them very fast.

 

[Shortround6]

I don't know about later Spitfires but the early ones had a two position control, either up or down, nothing in-between so trying to fiddle with flaps in a combat situation was not going to happen. On some of the ferry flights to Malta they fashioned wooden wedges to hold the flaps at 15 degrees (?) and closed the flaps on the wedges. After take-off and gaining safe flying speed they simple lowered the flaps, the wedges fell out and then the pilots retracted the flaps.
Perhaps later Spitfires got a different control system or the Hurricane had a different system or Curtiss Mohawks or Tomahawks did?

 

[Holtzauge]

The Spitfire flaps are pnuematic through small plumbing making them slow to move.

You sure about that? As I recall it they deploy and retract in a matter of a few seconds but I may be wrong. You have a source for this info?

 

[Holtzauge]

I don't know about later Spitfires but the early ones had a two position control, either up or down, nothing in-between so trying to fiddle with flaps in a combat situation was not going to happen. On some of the ferry flights to Malta they fashioned wooden wedges to hold the flaps at 15 degrees (?) and closed the flaps on the wedges. After take-off and gaining safe flying speed they simple lowered the flaps, the wedges fell out and then the pilots retracted the flaps.
Perhaps later Spitfires got a different control system or the Hurricane had a different system or Curtiss Mohawks or Tomahawks did?

Yes, AFAIK Spitfires just had the two position flap system and I'm not aware this was ever changed even on later marks. And this (the fully up or down only option) was also pointed out in the RAE report I mentioned as something that made them less useful in combat. And the report just looked at what would happen if flaps were deployed from a technical perspective and did not suggest that they were useful in combat.

 

[MiTasol]

The Hurricane had hydraulic flaps and when you selected up or down nothing moved until you manually activated the engine driven or hand pump hydraulic system to operate them. If you deactivate the system part travel the flaps will lock in that position which enables the pilot to select any flap position. Engine pump activation is via a lever beside the selector lever. All those controls, and the Dowty hand pump, are on the right side of the cockpit so the pilot must swap hands back and forth between the engine/prop controls and the gear/flap controls. From memory (going back to 1968) the Hurricane had both a landing gear and a flap indicator. I know the landing gear indicator was a large Dowty light display but I cannot remember what the flap indication was.

All the Curtiss H75, H81 and H87 series aircraft used the same basic hydraulic system with small variations. When you select flaps (or landing gear) up or down nothing moved until you manually activated the electric (main) or hand pump hydraulic system to operate them which enables the pilot to select any flap position.. If you deactivate the system part travel the flaps will lock in that position. Activation is via an electric switch on the control column. All those controls, EXCEPT the hand pump, are on the rear right side of the cockpit so the pilot does NOT swap hands back and forth between the engine/prop controls and the gear/flap controls. The hand pumps (main and emergency except on the later P-40s) are on the right. The later P-40 does not have a main system pump. All H75/P-36 and P-40 aircraft had both landing gear and flap indicators.

This was pretty much standard on all US and UK aircraft of the period except the Spitfire which kept the two position flaps up to the Mk 24. According to its manual the Spiteful had a hydraulic system for flaps and landing gear and set the controls on the pilots left like American aircraft did. I presume that the flaps could be selected to any position like on the the vast majority of British and American aircraft. Others here will know how the Europeans addressed these controls.

Many early aircraft required manual activation of the hydraulic systems and in many cases this was deleted from later models of the same aircraft.

 

[MiTasol]

You sure about that? As I recall it they deploy and retract in a matter of a few seconds but I may be wrong. You have a source for this info?

They are pretty quick on the ground with no air loads but the small size of the plumbing means they will be slow extending in flight even though the piston is fairly small. The air has a fair distance to travel from the air tank to the selector then to the piston and there are a lot of bends in the system. Somewhere on Spewtube there must be a video showing them extending in flight.

I do not have a reference but I do know from working on the horrible $%^& things. NOT my favourite aircraft by a very long way.

The Spitfire ALWAYS reminds me of the first day of my training where the instructor stated -- My job is to teach you the three ways to build an aircraft. The right way. The wrong way. And the British way. The first law of British aircraft design is why make it difficult when with a little bit of thought you can make it freaking near impossible. He should have also said that many British designs are metal aircraft using wooden design concepts like making ribs and formers from dozens of parts instead of punching them out of a single sheet of metal with flanges, beads and lightening holes to provide strength and lightness.

Bristol aircraft like the Blenheim and Beaufort are built more like American and European aircraft. Supermarine, Gloster, Hawker, Fairey and other aircraft follow the first law of British aircraft design.

Japanese aircraft are a mix of British and other concepts with far more British than American concepts and technology.

 

[Holtzauge]

They are pretty quick on the ground with no air loads but the small size of the plumbing means they will be slow extending in flight even though the piston is fairly small. The air has a fair distance to travel from the air tank to the selector then to the piston and there are a lot of bends in the system. Somewhere on Spewtube there must be a video showing them extending in flight.

I do not have a reference but I do know from working on the horrible $%^& things. NOT my favourite aircraft by a very long way.

The Spitfire ALWAYS reminds me of the first day of my training where the instructor stated -- My job is to teach you the three ways to build an aircraft. The right way. The wrong way. And the British way. The first law of British aircraft design is why make it difficult when with a little bit of thought you can make it freaking near impossible. He should have also said that many British designs are metal aircraft using wooden design concepts like making ribs and formers from dozens of parts instead of punching them out of a single sheet of metal with flanges, beads and lightening holes to provide strength and lightness.

Bristol aircraft like the Blenheim and Beaufort are built more like American and European aircraft. Supermarine, Gloster, Hawker, Fairey and other aircraft follow the first law of British aircraft design.

Japanese aircraft are a mix of British and other concepts with far more British than American concepts and technology.

OK, thanks for clearing that up. I think the only time I've seen them (the Spitfire flaps) operated is on the ground and what you say makes sense. Regarding the Spitfire, while I do agree with you on some aspects of British engineering (When I was young and into cars, we used to joke that Lucas who make the electrical systems on many British cars were the inventors of darkness ), I recently had the privilege to fly the Grace Spitfire at Sywell and I was absolutely delighted with the handling and surprised that such a big and heavy aircraft (compared to other aircraft I've flown) could feel so light and responsive. In addition, I was a surprised that the Spitfire was not as overly sensitive in pitch as it is sometimes made out to be. In fact, and rather to the contrary, I found this responsiveness quite pleasing and more of a feature than a bug. Maybe this is simply due to me being a glider pilot and that I was already accustomed to small and delicate control inputs, but I immediately took a liking to it and felt right at home with the small stick movements needed to fly it. So when it comes to the Spitfire's handling, I'm giving British engineering an 11 on a 10 graded scale!

 

[GrauGeist]

The first law of British aircraft design is why make it difficult when with a little bit of thought you can make it freaking near impossible.

This holds true to their automobiles, too.

They make fantastic machines, there is no question, however, whatever lead they take in engines and drivetrains is negated by their electrical systems...

 

[Holtzauge]

Regarding British aircraft engineering: The pilot I flew the Spitfire with said that you had to be very careful with the brakes (I never experienced this myself of course, since touching the brakes for me as a back-seater was a big no-no): First of all, when you operate the brake handle on the stick, there is quite a delay before the brakes "bite", and secondly, you have to apply rudder to indicate to the "system" which brake to operate. So given the delay before anything happens, you have to be very much on the ball or you will ground loop. And as if that's not enough, if you use them too frequently, then the drum brakes on the Spitfire will fade and you will have to wait quite some time until they cool off sufficiently to work again.

 

[MiTasol]

Regarding British aircraft engineering: The pilot I flew the Spitfire with said that you had to be very careful with the brakes (I never experienced this myself of course, since touching the brakes for me as a back-seater was a big no-no): First of all, when you operate the brake handle on the stick, there is quite a delay before the brakes "bite", and secondly, you have to apply rudder to indicate to the "system" which brake to operate. So given the delay before anything happens, you have to be very much on the ball or you will ground loop. And as if that's not enough, if you use them too frequently, then the drum brakes on the Spitfire will fade and you will have to wait quite some time until they cool off sufficiently to work again.

Same on the Lancaster but far more so as I found out the hard way. No damage but very close to that and dirty underwear. I was told, and later found correct, the secret on the Lanc in close areas was to partially apply the brake lever and walk the rudders from side to side so that the air was released from each side a little at a time which allowed the aircraft to move. Centring the pedals and applying full lever allowed the brakes to activate fairly quickly but you always had to think that extra distance ahead. On any straight area release the brakes fully or they overheat and fade. A nice aircraft otherwise on the ground but I never had the pleasure of flying in one.

 

[WARSPITER]

A nice aircraft otherwise on the ground but I never had the pleasure of flying in one.

Jogged my memory with that one. A long time car dealership owner here had a painting of a Lancaster in flight on his office
wall. I asked him about it one day when buying a car off him and he told me it was from a Lancaster flight that his father and
he were able to get on (he was only a young bloke at the time). It went over the Swiss Alps (somewhere there) and other passengers
were World War Two veterans on some sort of commemorative flight or similar.

He named some of the veterans who I didn't really recognise at the time but one name stuck - Adolf Galland.

 

[beers]

the IAS stall speed is 69 mph, while in reality the stall speed is about 87 mph TAS

If you went down to a low enough altitude, would those not converge to the same value? After all, IAS only decreases with altitude because there's 'less air' the higher you go. And if I'm not mistaken, Aerodynamics For Naval Aviators also claims comparing stall speeds is more accurate than other methods.

 

[MiTasol]

Hi beers (love your handle) and welcome aboard.

IAS compensation is less related to altitude or air density but because local pressure disturbances caused by the aircraft itself cause the indicator to misread.

You will note that many of the older prototype aircraft had a very long probe sticking out the front of the aircraft nose or wing. That was to measure the pitot and static air pressures from outside the disturbed air flow. You will also note that on many older prototype aircraft the pitot-static source moved during trials but, usually did not move once the aircraft went into production.

 

[Dimlee]

Back to Ki-43.
The author of this thread has provided interesting material about the Ki-43. It's a pity he left and did not extend the narrative until 1945.
Probably, the last operations of Ki-43 were over the Northern Kurils, Shumshu Island, in particular, in a short period of 17-20 Aug.. Ki-43-IIIa of the 54th Sentai were mentioned in various sources.
They escorted B5N2s in attacks against the Soviet transports and landing ships and strafed Soviet ships as described here:

Battle of Shumshu - Wikipedia

en.wikipedia.org

I failed to find any information about air-to-air battles over Shumshu.

 

[AerialTorpedoDude69]

Back to Ki-43.
The author of this thread has provided interesting material about the Ki-43. It's a pity he left and did not extend the narrative until 1945.
Probably, the last operations of Ki-43 were over the Northern Kurils, Shumshu Island, in particular, in a short period of 17-20 Aug.. Ki-43-IIIa of the 54th Sentai were mentioned in various sources.
They escorted B5N2s in attacks against the Soviet transports and landing ships and strafed Soviet ships as described here:

Battle of Shumshu - Wikipedia

en.wikipedia.org

I failed to find any information about air-to-air battles over Shumshu.

It's mentioned on the Japanese version of this Wikipedia page that there were no Soviet aircraft. My guess is that it was due to a combination of foggy weather, Soviet fighters' lack of range, and a lack of Soviet airbases in the region, although there's nothing in the article that explains why.

There's also an article in the Ki-43 page on this. The translation is confusing to me, but it suggests that there may have been an air battle but without anyone getting shot down (except the Kamikaze who was lost to AA fire).

一式戦闘機 - Wikipedia

ja.wikipedia.org

Here's an AI translation of the relevant passage:

Battle of Shumshu

In July 1945, near the end of the war, the 54th Air Regiment's main force of 11 aircraft was dispatched to Sapporo to strengthen air defense over Hokkaido. On August 10, the remaining four aircraft were also ordered to withdraw to Hokkaido by the 1st Air Division, and they were waiting for weather conditions to improve. Since April, the Navy had already begun withdrawing its ground forces from the northern Kurils, but air defense units and the Northeast Area Naval Air Group's Type 97 Carrier Attack Aircraft (B5N "Kate") were left behind.


On August 9, the Soviet Union entered the war against Japan. The Type 97 carrier attack aircraft launched attacks on the Kamchatka Peninsula on August 9 and 10, but since there had been no explicit order for aggressive action, no significant results were achieved.


On August 15, Japan accepted the Potsdam Declaration and decided to surrender. The Japanese military ceased combat, and army and navy units in the northern region began disarming. However, on August 18, the Soviet army landed on Shumshu Island, at the eastern end of the Kuril Islands, and engaged the Japanese Northern Raiding Unit (91st Division) in combat — the Battle of Shumshu.


With high morale, four Type 1 fighters (Ki-43 "Oscar") from the 54th Regiment and four Type 97 carrier attack aircraft from the Northeast Area Naval Air Group launched sorties to support the 91st Division. One of the carrier attack aircraft was shot down by anti-aircraft fire and lost, but it was reported that one transport ship received a direct hit and one minesweeper was sunk (results unconfirmed). The Type 1 fighters attacked minesweepers while also providing cover for the carrier attack aircraft (no confirmed results).


On the following day, August 19, the carrier attack aircraft carried out a show-of-force flight to intimidate Soviet naval vessels, but one plane was damaged during landing, leaving only two operational. As a result, three pilots from the Northeast Area Naval Air Group requested training in piloting the Type 1 fighter from pilots of the 54th Regiment.


Although the air engagements did not result in any major material damage, the efforts of the Type 1 fighters and carrier attack aircraft contributed to the Japanese garrison's valiant defense of Shumshu. Furthermore, the air battle on August 18 became one of the final aerial engagements of World War II.


After ceasefire negotiations were settled, on August 21, the Type 1 fighters and carrier attack aircraft, along with their pilots, escaped to Hokkaido. Of the three Type 1 fighters, Warrant Officer Ikeno's plane made a forced landing en route and he was taken prisoner by the Soviets; Sergeant Irie's plane went missing; and Sergeant Morinaga's plane mistakenly landed in Sakhalin but managed to hitch a ride on a ship and returned to Hokkaido a month later.


Thus, the aerial battles over the Kuril Islands ended with Japan's defeat and the conclusion of World War II.

EDIT: One interesting thing to note is that this was one of the only air battles in which the IJN and IJA flew together in a joint operation, with army fighters escorting navy aircraft.

 

[Dimlee]

It's mentioned on the Japanese version of this Wikipedia page that there were no Soviet aircraft. My guess is that it was due to a combination of foggy weather, Soviet fighters' lack of range, and a lack of Soviet airbases in the region, although there's nothing in the article that explains why.

There's also an article in the Ki-43 page on this. The translation is confusing to me, but it suggests that there may have been an air battle but without anyone getting shot down (except the Kamikaze who was lost to AA fire).

一式戦闘機 - Wikipedia

ja.wikipedia.org

Here's an AI translation of the relevant passage:

Battle of Shumshu



EDIT: One interesting thing to note is that this was one of the only air battles in which the IJN and IJA flew together in a joint operation, with army fighters escorting navy aircraft.

Thank you for the translation, very interesting.

 

[cammerjeff]

Just stumbled on this Picture

Caption - A rare combat photograph of a Japanese Ki-43 Hayabusa (Allied reporting name "Oscar") intercepting USAAF B-25 Mitchells over the Kurile Islands, November 6, 1944. A close examination of the Oscar shows that one of the landing gear is lowered, likely indicating damage to the hydraulic system.

Source Picture of the Week – Page 3 – Inch High Guy

 

[GrauGeist]

How about a shot of a KI-43 and an A6M3?

(Photo credit: Matt Booty, 2021)