Correct the Russian P39Q and P63 models!!!

Here are some links to the history of the Russian use of some 3,000+ American built P-39/P-63 used in the Great Patriotic War.

These links will show that the P39Q/P63 was a superior fighter at alt. below 15,000ft. At lower levels the P39/P63 not only out-turned and out performed the 190's and 109's but out-gunned them as well. Russian modification to the 37mm canon was to increase magazine capacity from 30 to 58 rounds. ALL but the first 300 planes had this modification!!! (300 of 3,200+ planes!).
America further sent 1.2 million rounds of High Explosive canon rounds to Russian forces.

It is time to correct this great injustice of having a P39 model not anywhere near its real-life performance envelope!

Please correct the flying model, the canon capacity and the canon "lethality". the 190s have their 30mm. the 37mm with HE shells should be MUCH more deadly!

Thank you!!!!!!




http://www.acepilots.com/planes/p39_airacobra.html

http://www.acepilots.com/planes/soviet_p39_airacobra.html#top

 

it's not enough.
i guess you really believe irondog to be an überplane, but it is actually not.

we'd like to see you provide data like
http://www.fourthfightergroup.com/eagles/spittest.html
or at least
http://www.airwarfareforum.com/viewtopic.php?t=2973

the worst are (though not completely bad)
http://www.csd.uwo.ca/~pettypi/elevon/baugher_other/
http://home.att.net/~jbaugher1/oldseriesfighters.html

 

Hi Bhoover,

>It is time to correct this great injustice of having a P39 model not anywhere near its real-life performance envelope!

Hm. I haven't checked in-game performance yet. Have you? Top speed over altitude would be nice.

But I doubt the P-39Q would have any advantage over the Me 109G. The V-1710-85 at 57" Hg boost topped out at 1420 HP @ 9000 ft (with ram), while the DB605A at 1.30 ata boost yielded 1410 HP at a similar height.

While the P-39Q has a larger wing than the Me 109, it also uses a different profile with a lower maximum lift coefficient. From a NACA report on the P-39, I'd say the resulting instantaneous turn rates should be almost equal with a slight advantage for the Me 109, while the sustained turn should be clearly in favour of the Me 109 since it's almost 300 kg lighter. The lower weight also favours the Me 109 in the climb.

And the P-39 had a nasty, abrupt stall which according to contemporary reports made it a poor gun platform, while the Me 109 had excellent controllability at the edge of a stall.

I'm not quite certain on top speed, but a P-39D with 57" Hg would be slower than the Me 109G-2 even at the P-39's best altitude. This might be different with the V-1710-85, so I won't comment on this point.

>the 190s have their 30mm. the 37mm with HE shells should be MUCH more deadly!

Definitely not The 37 mm HE shells had a total energy of about 360 kJ, compared to the 30 mm mine shells' 510 kJ. Add the MK108's greater rate of fire (10 per second compared to 2.5 per second), and the 30 mm comes out with 5 MW compared to 0.9 MW, or roughly five times as powerful.

OK, the 37 mm has a much higher muzzle velocity, so it's easier to hit, but that's already modelled

Oh, and I believe the P-39Q is actually a very capable plane in the game. Don't underestimate it, if you keep up the speed it's the Luftwaffe's terror

Regards,

Henning (HoHun)

 

IMHO:
i'd be careful comparing destructive effect basing on specific heat of exothermicity, because it does not consider brisance (shattering effect) and fougasseness.

also, i won't trust pure kinetic energy, because it does not consider armour penetration capabilities, that depend on velocity, calibre, nose shape, core hardness, angle of impact and more factors.

in most cases 1x37mm hit doomes fighter and even med.bomber. in the game it is made through exactly 1 hit (disregarding recent dm experiments).
1x30mmMGeshoß is quite harmful too, but it's much more easy to hit with it, adding here twice ammo load. so i think that 30mm must be about twice less harmful than any 37mm in the game.

 

Agree with -exec-. IMHO the energy of hit for M4 37mm gun has to be impoved a bit.. 25..35% max.
Otherwise we can get P39D in the beginning of the TOD which can be too good "spray d8 1 x hit = 100% kill buff-killer".

 

But Soviet Air Force very freguince use P39Q Lite, without wings Browning 0.50 (-100-120kg) other facilitated components.

Soviet pilots fly at P39Q frequence befor flied on I-16, too has bad stability.

 

Wasn't most of Hartmanns 356 kills done whilst flying in the Gustav?


Malin

 

I may be mistaken, but p-63 didn't see much battle in russian army in ww2. Russians received first p-63 in June 1945 and haven't had much chance to use them against Japanese. I doubt there is a single plane in ww2 shot down by p-63.
So its poiintless to introduce it, even if it does have super performance.

37mm shell is definitely more powerful in kinetic energy as in explosive than german 30mm.

While p-39 is a capable plane there was no clear advantage over german fighters. Except firepower

 

Hi Exec,

>i'd be careful comparing destructive effect basing on specific heat of exothermicity ... also, i won't trust pure kinetic energy

The figures I quoted are the sum of both. Of course, you're right that my comparison is a simplification, but it's the best simplification available so I don't hesitate to apply it.

Anyway, the M4's high explosive shell and the MK108 mine shell are very similar in their effect mechanism, so this comparison really is a no-brainer.

>so i think that 30mm must be about twice less harmful than any 37mm in the game.

Well, I commented on reality, not on the game. If you're right, that means there's no reason to complain about the 37 mm anyway

Regards,

Henning (HoHun)

 

Hi Hammer,

>But Soviet Air Force very freguince use P39Q Lite, without wings Browning 0.50 (-100-120kg) other facilitated components.

331 lbs according to the P-39Q manual, or 150 kg. That helps a bit, but the Messerschmitt still has the better power loading, about equivalent lift loading, and better controllability in the turn.

I'd rather see the removal of the wing guns as a sign that the P-39Q was not a superior aircraft in combat. The VVF obviously felt that something had to be done to improve performance.

>Soviet pilots fly at P39Q frequence befor flied on I-16, too has bad stability.

Well, the P-39Q just dropped a wing in a steep turn with no warning at all. That means you either don't go too close to the limit, not flying the aircraft to its full (theoretical) capability, or you risk dropping out of the turn losing a lot of angle. And if you try to pull a bit too much to get the gunsight on target, the plane will roll away out of control. That's nothing one could overcome with piloting skill, I'm afraid.

Regards,

Henning (HoHun)

 

Hi Alec,

>While p-39 is a capable plane there was no clear advantage over german fighters. Except firepower

Well, the British replaced the 37 mm cannon with a 20 mm Hispano and felt that was an improvement.

The Hispano II actually had a firepower of 1.06 MW, compared to the M4's 0.91 MW, while weighing only half as much.

The Firepower even of an Fw 190A-4/light was clearly superior to the P-39's.

Regards,

Henning (HoHun)

 

P39Q Lite(~3300kg) Wing Load 167kg/M^2 it equal wing Load Yak-9
But P39Q can use not full fuel Tank(On east front usually far from being flied)
Bf.109G-2 it (3023kg) Wing Load 187kg/M^2
Soviet data for turn Bf.109G-2 20-21.5 sec and radius 290m at alt 1000m
for P39(It is not specified for what model) 19 sec and 253m at alt 1000m
Bf.109G-2 has advanced in Power load P-39Q has advanced Wing Load.

P-39Q had good stall. But bad spin. Very trouble out spin if u has small ammo. (See attach)

 

It saw a bit against Japan.

P-63A was tested by NII VVS in march 1945.
So june 1945 is clearly wrong date, late 44 would be more likly.

 

I' afraid they are quite diffirent.

M4 gives a lot of fragments, MK-108 creates more powerful, but local blast, no much of the shell left to create fragments.

 

P-39 would have lower wing loading.

I-16 do the same and were considered as dangerous as P-39 (even more i guess), althru it easly recover from spin.

Or you control your aircraft better.

If you pull it too much - every plane do the same

That's exactly what you can overcome with pilot skill.

 

I guess they just prefer to have british armament.

Or you would have to imagine that british felt their 0.303 MGs were improvment over american's 0.30

i guess you mean per some period of time, althru i fail to see per what period of time you were able to calculate such values.

My calculations shows about ~500 kW of muzzle energy per second for Hispano II and ~270 kW for M4

Still 1 hit by M4 shell would destroy Fw 190A.

 

Typical P-39Q Light would weight 3445 kg
So it will be 173,5 kg/m2

Q-1 had 87 gallons(factory kits supplied to rise it to full 120 gallons) of fuel = ~ 330 liters
rest of Q version had 120 gallons of fuel = ~455 liters

Guess u wouldn't want to fly it without full tank (and would want Q-1 fuel capacity up to full 120 gallons)

It was specified - P-39D

We can speculate it was measured about same way as 17-19 seconds for Yaks, especially considering about 3 kg per hp powerloading of P-39D
Or lets say using manifold pressures above permitted.

Problem is P-39 stalls abruptly and without adequate warning





And then easily goes to spin if you do something wrong


http://www.airwar.ru/other/bibl/p39d_flying.html
page 24

 

Я смотрел здесь http://www.acepilots.com/planes/p39_airacobra.html.
Где можно посмотреть что данный вес имеено для P39Q без крыльевых браунингов ?

Про то что это P-39D я видел только в книжке про аэрокобру
составитель В.А. Бакурский. Но как такое получить на P-39D даже незнаю (У меня при Cyдоп=1.2 и полетном 3556кг из той же книги почти 23,8 сек и радиус 298м при Cyдоп=1.3 23,1 сек и радиус 275м )Кстати по Аллисону V-1710-35 и 85 графика высота мощность нету случайно или хотя бы мощности на критических высотах с указанием высот?

 

В "Самолётостроении":

http://badger.front.ru/237.htm

Или в РЛЭ P-39Q-1, где видно что вес 7570 lbs с 4 пулеметами и с 87 галлонами горючего.

В "Самолётостроении" тоже самое, смотрите выше страницу.

Так же как на яках.

А в "Самолётостроении" радиус для P-39 так и указан: 253-280 метров.

Графиков нет, таблица по -85 есть в РЛЭ, по -35 тоже есть таблицы, лень искать, можно здесь:

http://www.enginehistory.org/moddesig.htm

Там нет WEP, но его у -35 и не было