SHOULD the P39 have been able to handle the Zero? Was it training or performance?

[XBe02Drvr]

The airplane performed a portion of an inverted snap roll, faltered momentarily and then did one or two turns of an oscillatory inverted spin. It then moved suddenly into a normal left hand spin

Ever see an airshow acro plane do a Lomcevak? You just described it to a tee. I'm told the word is Czech and is (mis)translated as "crazy mixed-up headache". Having ridden through a couple in a Pitts, I can vouch for the accuracy of the term. The ultimate sensation of hostageness. You ever notice that nobody does them at low altitude at airshows (or anywhere else)? Takes a few seconds to uncage your eyeballs afterward.
Days of future passed! That sort of behaviour, an inverted oscillatory spin with the nose whipsawing up and down and the rotation rate and bank angle fluctuating randomly and not synchronously, became pretty common in the jet age. IIRC, spin in the F4J was described as: "random oscillations around all three axis with buffeting, a high rate of descent, and probable dual flameout". IIRC, recovery was: "average fluctuations of AOA needle to determine if positive or negative stall, average turn needle to determine direction of rotation, apply appropriate stick and rudder for type of spin. Deploy RAT if flameout occurs. If control not regained passing 10,000 AGL, EJECT."
I knew a crew who missed that last directive by a thousand feet, stopping rotation by 9,000 and still augered in. They managed to achieve a level pitch attitude passing through 1,000, but at some phenomenal G load and an impossible sink rate, and the plane snapped inverted in the midst of the ejection sequence.
Cheers,
Wes

 

[Greg Boeser]

P-39expert cites Attack and Conquer.
So will I. The 8th FG entered combat 30 April 1942 with P-39Ds and P-400s, within 5 days they had lost 9 pilots and 14 aircraft. Clearly, the pilots were no match for the Tainan AG. The P-39 lacked range to effectively bring battle to the enemy, and were hard pressed to defend their own air base. slow climb performance meant that with the short warning afforded the Port Moresby defenders, they often had no choice but to scramble out to sea to avoid being swatted down while in the climb. Trying to engage the Japanese while still in a climb was suicide as demonstrated by the 75 Sqn. RAAF.
The 8th and 35th FGs held the line in New Guinea during 1942, but suffered considerable losses.
The 80th FS was reequipped with P-38s and entered combat 30 March 1943. The P-38 was a game changer. As the book states, the 35th and 36th Fighter Squadrons continued to fly combat missions in spite of the fact that the P-38 was pushing the fight out of the radius of other fighter types. Both squadrons eventually re-equipped, The 35th got P-40Ns in late 43, and the 36th got some P-39Qs before converting to P-47s in early 44. Both eventually got P-38s

 

[Elmas]

View: https://youtu.be/og7fCw85Qns


Performed by Maggiore Andrea Rossi, then (2005) "Solista" of the Pattuglia Acrobatica Nazionale.

 

[Elmas]

View: https://youtu.be/hLeYWkx2Jlg


If you watch at this video the Instructor do insist that landing in P-39 must be done on the main undercarriage, keeping the nose well up to the end ( from 33'.00 circa). As all airplanes with tricycle landing gear must do, of course.

But probably the tricicle undercarriage, that required this markedly nose-up attitude was one of the reasons responsible for the bad handling of P-39 at low speeds.

The combination of nose-up, CG aft, ammunition expended, no wash-out in the wings, inertia coupling due to the position of the engine and possibly other incidental factors like a little bit to slow landing speed ("..be careful not coming too fast" says the Instructor at 32.00...), some unfavourable wind conditions, a jerky handling of the stick from a inexperienced Pilot, could have led very easily to a nasty situation.

 

[P-39 Expert]

P-39expert cites Attack and Conquer.
So will I. The 8th FG entered combat 30 April 1942 with P-39Ds and P-400s, within 5 days they had lost 9 pilots and 14 aircraft. Clearly, the pilots were no match for the Tainan AG. The P-39 lacked range to effectively bring battle to the enemy, and were hard pressed to defend their own air base. slow climb performance meant that with the short warning afforded the Port Moresby defenders, they often had no choice but to scramble out to sea to avoid being swatted down while in the climb. Trying to engage the Japanese while still in a climb was suicide as demonstrated by the 75 Sqn. RAAF.
The 8th and 35th FGs held the line in New Guinea during 1942, but suffered considerable losses.
The 80th FS was reequipped with P-38s and entered combat 30 March 1943. The P-38 was a game changer. As the book states, the 35th and 36th Fighter Squadrons continued to fly combat missions in spite of the fact that the P-38 was pushing the fight out of the radius of other fighter types. Both squadrons eventually re-equipped, The 35th got P-40Ns in late 43, and the 36th got some P-39Qs before converting to P-47s in early 44. Both eventually got P-38s

Keep in mind a few salient points, first these were older P-39s with the lower rated engine and way too much weight. With the ever present drop tank their combat ceiling (altitude above which any plane will climb at only 1000fpm or less) was about 18000'. The Bettys came in at between 18000' and 22000' with their Zero escort at about 24000'. These older P-39s (D,F,K,L) could have easily been modified in the field by simply removing the 4 x .30 wing guns along with their mounts, chargers heaters and ammunition boxes (and of course the ammo itself which was the heaviest component) and these planes would climb with the P-38s that, by the way, were not even available until very late in the year. And those Jap raids were frequently intercepted by those P-39s, no radar and extra weight included.

Second, the Japanese pilots were among the best in the world being Navy carrier pilots with experience in China. Our kids at PM were all fresh out of flying school with no experience except for Buzz Wagner who supposedly got off the ground at Pearl Harbor. Most experts consider pilot quality to be more important than plane quality all other factors being equal. Theirs were much much better at this point in the war.

Third,we didn't have effective radar until after August 1942 so the raids were largely unopposed. These raids could come at any time from Lae only 200 miles away and their Zero escort didn't even need drop tanks. Later at Guadalcanal the Jap raids came from much farther away so they almost always came at noon making them very predictable.

Fourth, we were tremendously outnumbered. Japanese had functioning bases all along the NG coast backed up by their huge base at Rabaul. Their maintenance facilities were functional. Our maintenance/supply early on at Moresby consisted mainly of pulling a functional part off of one of the many wrecks at the end of the runway. By the time the P-38 appeared in the theater attrition at Moresby, Coral Sea, Midway and the first three months of Guadalcanal had seriously reduced the Japanese Navy pilot quality and our pilots were much better trained than in April '42.

The fact that the green outnumbered American kids kept the Japanese out of Moresby was a real tribute to their courage and tenacity. Lighter equipped P-39s and functioning radar would have made the job a lot easier. The later arriving Lightnings benefited from better pilots, declining Jap pilots, functioning radar and much more efficient maintenance.

 

[P-39 Expert]

View: https://youtu.be/hLeYWkx2Jlg


If you watch at this video the Instructor do insist that landing in P-39 must be done on the main undercarriage, keeping the nose well up to the end ( from 33'.00 circa). As all airplanes with tricycle landing gear must do, of course.

But probably the tricicle undercarriage, that required this markedly nose-up attitude was one of the reasons responsible for the bad handling of P-39 at low speeds.

The combination of nose-up, GG aft, ammunition expended, no wash-out in the wings, inertia coupling due to the position of the engine and possibly other factors like a little bit to slow landing speed ("..be careful not coming too fast" says the Instructor at 32.00...), some unfavourable wind conditions, a jerky handling of the stick from a inexperienced Pilot, could have led very easily to a nasty situation.

All planes were encouraged to land on their main landing gear first. The slight nose up attitude on the ground did not transfer to flight, the P-39 flew level like a normal plane. P-39 was much easier to handle on the ground than a tail dragger, you could see straight ahead and taxied like driving a car.

 

[Elmas]

All planes were encouraged to land on their main landing gear first. The slight nose up attitude on the ground did not transfer to flight, the P-39 flew level like a normal plane. P-39 was much easier to handle on the ground than a tail dragger, you could see straight ahead and taxied like driving a car.

I cannot more unconditionally agree with you about that, and so does Com.te Galbusera in his interview and also Jeffrey Quill, the well known Spitfire test Pilot, was amazed about the handling of P-39 on the ground, and he did insist to have Supermarine Attacker with a tricycle landing gear.
"Very strange that Vickers, who was a main producer of equipment for landing gears, did not accept my proposal" he remembers in his memories.
Probably the British were so scared from landing P-39s after the one and only mission they flew wit it to exclude completely tricycle landing gear from their aeroplanes once and for all. Joking, of course. I know that Meteor and Vampire had tricycle landing gear.
While I do easily accept the fact that P-39 flew level ( but up to a point...) our opinions differ about the handling of P-39 in flight, and in particular at landing...

 

[P-39 Expert]

For those who have not read it, this is an interesting account of the 67th Ftr Squadron and its P-400's on Guadalcanal:

https://ia902205.us.archive.org/17/items/PacificCounterblow/PacificCounterblow.pdf

It says they looked into reducing the weight of the P-39 and by the end of September 1942 were able to strip a P-39K of 650 lb of its original equipment. It also says that Gen Harmon asked DC for the P-38, P-47, or the P-40 with the Merlin engine. I guess that explains why those P-40F's got to Guadalcanal.

The P-39 comes off better in this Guadalcanal summary than others that I have read.

The P-400s had no oxygen (wrong equipment) so any flying above 12000' was forbidden. Those that got to 14000' had to be feeling the effects.

After regular P-39s arrived they seem to have handled themselves admirably. Interesting how on some missions they were tasked with bombing and then climbing up to become their own escort. More efficient than having SBDs for bombing and Wildcats for escort.

No Wildcat in WWII could match the speed of any P-39 at any altitude and were 30-40mph slower at all altitudes. Standard P-39 could match the Wildcat in climb and outclimb with later models (M, N, Q) substantially outclimbing it. Wildcats were effective against the Japanese because of superior pilot quality of the Navy/Marine aviators.

 

[MIflyer]

The F4F-4 had a two stage supercharger and its success as an interceptor owes much to that fact. Right about the altitude where a P-39 hit the wall the F4F literally kicked into high gear. Its maneverabilty was quite good as well.

Now why did the Wildcat have a two stage supercharger? I was going to write my next article on that and was doing research at the Smithsonian Air and Space Museum before Wings/Airpower folded. The answer comes from four events:

1. Billy Mitchell, 1921.
2. YB-17 interception of the liner Roma
3. Y1B-17
4. USN Panics

 

[MIflyer]

Just read a couple of accounts of the P-39 in a book I bought recently, "Flying American Combat Aircraft of WWII."

One account was from the Med, the 35th Fighter Squadron; I found this especially interesting for I have read very little of any P-39 use in Europe. The other is from Guadalcanal and that's always interesting. Here is a summary:

Med and the 'Canal: Never had it tumble but it stalled almost without warning and many crashes resulted from pilots getting too slow on final, especially in training. Some pilots did say they tumbled and it took them 15,000 ft to recover. A stall in the traffic pattern probably meant it was all over. It was very easy to land if you were careful about airspeed.

Med and the 'Canal: Very sensitive on the controls, and better than the P-40 and P-47 in that respect but it also offered a danger to novice pilots

The 'Canal: Fastest climbing US fighter from sea level to 12,000 ft but you hit a brick wall at 12,000 ft and was virtually worthless above 15,000 ft.

Med and the 'Canal: Range was too much short. At the 'Canal they were often escorting troopships and had to remain in that vicinity, so hit and run tactics were not an option. On returning to base on the "Canal they usually had fuel enough to land, period, not enough to go around. On one case the P-39's were returning from a patrol and had just enough fuel to land, while overhead P-40's were dogfighting with Zeros. One P-40 had a Zero on his tail he could not shake, at about 2000 ft and was yelling for help. While the P-39's were coming into land the P-40 with the Zero about 40 ft behind were at about a 90 degree angle to them. One of the P-39's made a sharp bank and used a 70 degree deflection shot to blow away the Zero, then rolled back onto final and landed.

Med and the 'Canal: Very easy to taxi but there were serious overheating problems on the ground. P-39's had to take off either first or last when mixed in with other aircraft, usually last to conserve their limited fuel.

Med and the 'Canal: The 37MM was great for strafing and a single well placed shot could clean the troop out of a barge or destroy an enemy automobile.

The Canal: The 37MM was worthless in air combat due to the different trajectory from the machine guns. He never even fired the 37MM in air combat.

Med and the 'Canal: Great airplane for bellying in, ditching, or bailing out of.

The 'Canal: Maneuverability was nil at 12,000 to 15,000 ft and poor below that.

Med: Had relatively poor turning characteristics.

 

[P-39 Expert]

The F4F-4 had a two stage supercharger and its success as an interceptor owes much to that fact. Right about the altitude where a P-39 hit the wall the F4F literally kicked into high gear. Its maneverabilty was quite good as well.

Now why did the Wildcat have a two stage supercharger? I was going to write my next article on that and was doing research at the Smithsonian Air and Space Museum before Wings/Airpower folded. The answer comes from four events:

1. Billy Mitchell, 1921.
2. YB-17 interception of the liner Roma
3. Y1B-17
4. USN Panics

It did have a two stage supercharger, the first in any production combat plane. Didn't seem to be as efficient as others. Look at the performance graphs, I stand by my statement about the P-39 being faster at all altitudes.

Regarding the P-40, it had the same engine as the P-39 and weighed 750# more (8400-7650). There is no physical way possible for the P-40 to have the same performance in climb or level speed. Physically impossible. Merlin P-40 was faster than the Allison P-40, but no faster then the P-39.

 

[P-39 Expert]

Just read a couple of accounts of the P-39 in a book I bought recently, "Flying American Combat Aircraft of WWII."

One account was from the Med, the 35th Fighter Squadron; I found this especially interesting for I have read very little of any P-39 use in Europe. The other is from Guadalcanal and that's always interesting. Here is a summary:

Med and the 'Canal: Never had it tumble but it stalled almost without warning and many crashes resulted from pilots getting too slow on final, especially in training. Some pilots did say they tumbled and it took them 15,000 ft to recover. A stall in the traffic pattern probably meant it was all over. It was very easy to land if you were careful about airspeed.

Med and the 'Canal: Very sensitive on the controls, and better than the P-40 and P-47 in that respect but it also offered a danger to novice pilots

The 'Canal: Fastest climbing US fighter from sea level to 12,000 ft but you hit a brick wall at 12,000 ft and was virtually worthless above 15,000 ft.

Med and the 'Canal: Range was too much short. At the 'Canal they were often escorting troopships and had to remain in that vicinity, so hit and run tactics were not an option. On returning to base on the "Canal they usually had fuel enough to land, period, not enough to go around. On one case the P-39's were returning from a patrol and had just enough fuel to land, while overhead P-40's were dogfighting with Zeros. One P-40 had a Zero on his tail he could not shake, at about 2000 ft and was yelling for help. While the P-39's were coming into land the P-40 with the Zero about 40 ft behind were at about a 90 degree angle to them. One of the P-39's made a sharp bank and used a 70 degree deflection shot to blow away the Zero, then rolled back onto final and landed.

Med and the 'Canal: Very easy to taxi but there were serious overheating problems on the ground. P-39's had to take off either first or last when mixed in with other aircraft, usually last to conserve their limited fuel.

Med and the 'Canal: The 37MM was great for strafing and a single well placed shot could clean the troop out of a barge or destroy an enemy automobile.

The Canal: The 37MM was worthless in air combat due to the different trajectory from the machine guns. He never even fired the 37MM in air combat.

Med and the 'Canal: Great airplane for bellying in, ditching, or bailing out of.

The 'Canal: Maneuverability was nil at 12,000 to 15,000 ft and poor below that.

Med: Had relatively poor turning characteristics.

P-39 would overheat if kept on the ground. Not as big a problem as you think, since the P-39 taxi was with full forward vision and you just drove it like a car. After starting the engine you just did your preflight checks on the way to the end of the runway. Once you got there, mag and prop check and then just take off. The tail draggers couldn't see straight ahead over the engine so they had to serpentine everywhere or have a guy sit on the wing.

The 37mm cannon was better than most give it credit for. Yeager said the 37mm "had some trajectory" and was like "throwing a grapefruit". But the trajectory was not that bad inside the effective air to air gunnery range. Inside of about 400 yards the difference in the drop of the .50 caliber MGs and the 37mm cannon was negligible so you could fire all three at once. One strike from the 37mm cannon was usually deadly for anything it hit. Outside of 400 yards you were not likely to hit anything anyway. The jamming problem was largely solved from the L model on with the little exhaust vents just ahead of the gun bay doors. The gun was an "open breach" that would freeze at higher altitudes. Those little vents exhausted heated air ducted up from the coolant radiator through the cockpit effectively heating the gun bay to near cockpit temperature. Russians considered the 37mm more reliable than the 20mm in the P-400 and D-1. For all the P-39 faults it did have excellent cockpit climate control.

 

[pbehn]

Regarding the P-40, it had the same engine as the P-39 and weighed 750# more (8400-7650). There is no physical way possible for the P-40 to have the same performance in climb or level speed. Physically impossible. Merlin P-40 was faster than the Allison P-40, but no faster then the P-39.

This may be true, that the P39 was faster than the P40 but it is an aerodynamic issue not weight, the P51B was faster by about 30MPH than a Spitfire with the same engine and heavier too. How did the P51 and P39 compare with identical engines?

 

[pbehn]

No Wildcat in WWII could match the speed of any P-39 at any altitude and were 30-40mph slower at all altitudes. Standard P-39 could match the Wildcat in climb and outclimb with later models (M, N, Q) substantially outclimbing it. Wildcats were effective against the Japanese because of superior pilot quality of the Navy/Marine aviators.

The Wildcat was a carrier capable fighter which made its first "kill" on Christmas day 1940 over Scapa Flow, it was very robust, easy to fly and had excellent range, it remained in service with the USA and UK navies until the end of the war because although the Hellcat was better in most respects it wasn't better at all of them, the Hellcat being introduced in 1943.

 

[michaelmaltby]

".... How did the P51 and P39 compare with identical engines?"
The Alison-powered P-51 was more successful ... cheap to build. easy to maintain, no bad habits except high (laminar flow) landing speed and the short comings associated with tail draggers AC's, IMO.

 

[pbehn]

".... How did the P51 and P39 compare with identical engines?"
The Alison-powered P-51 was more successful ... cheap to build. easy to maintain, no bad habits except high (laminar flow) landing speed and the short comings associated with tail draggers AC's, IMO.

Chuck Yaeger preferred the P-51.

 

[Peter Gunn]

*SNIP*

Regarding the fuselage tank, I read a pilot's comments that it was a court martial offense to use the fuselage tank before exhausting the drop tanks. Any usage of the fuselage tank prior to exhausting the drop tanks meant a loss of range if the drop tanks had to be dropped before they were empty. Use your fuselage tank before your drop tanks and you have one third less internal fuel after they are dropped.

*SNIP*

Say what now? I believe you read wrong.

Also the Luftwaffe was beaten by June '44? Interesting. They were certainly in no position to challenge Overlord, but beaten? Hardly likely.

 

[pbehn]

Many evaluations of the P-39 contradict that statement about stalls. and speaking about control reversal. On the P-39 with wing guns and full ammo loads the proper spin recovery use of ailerons was opposite the proper use of ailerons without or with light load of ammo.
.

I find this intriguing, my "in" is 100% "trigued"

If a full ammunition load requires action "A" in a stall, AND no ammunition requires action "B" in a stall, AND action "A" and action "B" are completely opposite. There must be a point of ammunition weight where the conditions cross over. My question is, at this point do both actions "A" and "B" both work equally well or is the pilot completely screwed with no chance?

 

[tomo pauk]

Regarding the P-40, it had the same engine as the P-39 and weighed 750# more (8400-7650). There is no physical way possible for the P-40 to have the same performance in climb or level speed. Physically impossible. Merlin P-40 was faster than the Allison P-40, but no faster then the P-39.

P-40F (1st delivered in January 1942) was sligtly faster than the P-39D, K or L on most of altitudes, it provided better range/radius, armament suite was better, range was longer, service ceiling was higher.

 

[Elmas]

Pierre Clostermann's memories are certainly controversial, but he states that, in May 1945, a few hours before Doenitz called to surrender, his unit lost six of the twelve Tempests that strafed a German airport. From memory, I'm not at home now.

The Nazi Titanic