Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: Krusty on October 05, 2005, 11:39:29 PM
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Just saw a pic of a P38J with 7 rockets under each wing. Not in the tree-holder, spread out one each under the wing for a total of 7 each side.
Just curious, why are we limited to 10 rkts?
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That was only a test. It would have required some serious changes in production which wasn't worth it. The rocket tree was the solution that worked best.
What you saw wasn't ever used operationally
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cool, thanks for the info!
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I think some P47's and even Tiffies sported a double set of rockets - like 7 or 8 on each wing!
I've also heard about tiffies that had no cannons. Maybe the same?
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Originally posted by Angus
I think some P47's and even Tiffies sported a double set of rockets - like 7 or 8 on each wing!
I've also heard about tiffies that had no cannons. Maybe the same?
For the typhoon I've seen pict of typhon with 10 rockets or 4 rockets + DT.
Some tiffies had their inner gun removed to make FR.1B
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Originally posted by Angus
I think some P47's and even Tiffies sported a double set of rockets - like 7 or 8 on each wing!
I've also heard about tiffies that had no cannons. Maybe the same?
Don't know about the Tiffies, but those were experiments on the P-47's, and possibly some unapproved field modifications, same as the P-38. I've talked to guys who had seen planes in their units modified by some of the creative ground crews. Like 6 and 8 gun noses in the P-38's (all 50 cal), and a P-38 with 4 20MM cannons in the nose. Not that I wouldn't like to have a P-38J with 4 20MM cannons in the nose, but I can see where unapproved field modifications and experiments/prototypes just won't work here.
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Mmm, I'd love to see a P-38 with that kind of firepower, it doesn't really need an upgrade, I beleave the 38 has some of the most effective hitting power in the game thus far, the 4x 20mm's do have harder hit but on the planes that there mounted, there normaly on the wings. But the 38s guns all tightly packed in the nose like that, I can't think of anything better then with 4x 20mm cannons... Ahh... :-D
Edward
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Sometimes I wish they'd never taken out the 37mm Oldsmobile cannon the P-38 had before they replaced it with the 20mm Hispano.
ack-ack
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Originally posted by Ack-Ack
Sometimes I wish they'd never taken out the 37mm Oldsmobile cannon the P-38 had before they replaced it with the 20mm Hispano.
ack-ack
Problem is they never really put it in :)
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ExCal,
It is brutal. To try it out fly the Mossie as a fighter for a bit. It doesn't perform as well as a P-38, but it'll give you an idea of what four 20mm Hispanos in the nose are like.
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Originally posted by Guppy35
Problem is they never really put it in :)
The 37mm Oldsmobile cannon was in the YP-38 and the P-38D, while the YP-38 was an experimental test bed, the D was an operational model. Although, only IIRC, 32 were produced and some of the Ds had the 37mm replaced with a 23mm cannon, which was later swapped out for the 20mm in the E model.
ack-ack
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Originally posted by Ack-Ack
The 37mm Oldsmobile cannon was in the YP-38 and the P-38D, while the YP-38 was an experimental test bed, the D was an operational model. Although, only IIRC, 32 were produced and some of the Ds had the 37mm replaced with a 23mm cannon, which was later swapped out for the 20mm in the E model.
ack-ack
Gotta find me a D picture that actually shows an operational D with a cannon at all. Only D photos I've ever seen show the opening blanked off and only the 4 MGs.
Bodie's book on the 38 is clear that the 38D never carried the cannon. And I tend to believe Bodie since his book on the 38 is the best overal coverage on the Lightning out there in my opinion
Nothing else I've seen or read says that it ever got beyond the drawing board and was never on an operational D model 38.
I have seen photos of a 38 modified by the 80th FS with the 6 50 call set up that was used in combat.
(http://www.onpoi.net/ah/pics/users/810_1128648857_6gun38.jpg)
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I thought the D's never saw combat and that they were just used as trainers?
Honestly, never seen a picture of a D model with a 37mm cannon. Only thing I've seen that it said it carried the 37mm and in some cases a 23mm is in the gun package specs for the D model.
ack-ack
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Originally posted by Guppy35
I have seen photos of a 38 modified by the 80th FS with the 6 50 call set up that was used in combat.
(http://www.onpoi.net/ah/pics/users/810_1128648857_6gun38.jpg)
Anything that shows that this gun package was more effective than the quad .50s and 20mm Hispano?
ack-ack
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Is this a D or an E model?
(http://www.airwar.ru/image/idop/fww2/p38/p38-8.jpg)
ack-ack
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Originally posted by Ack-Ack
Is this a D or an E model?
ack-ack
That's a D model. Just the 4 MGs.
Also note the lack of the curved fillet where the wing meets the cockpit pod. That apparently made a huge difference when they added it as it prevented the tail buffet they'd been dealing with previously.
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Originally posted by Ack-Ack
Anything that shows that this gun package was more effective than the quad .50s and 20mm Hispano?
ack-ack
According to the 8th FG history, the 80th FS said it was devestating in it's effectiveness but was dropped for some reason.
I suppose it was just to much work to modify more, or use it on a larger scale?
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OK, so all the design specs that I've seen for the D that showed the default guns package as a 37mm or 23mm and 4x .50 cals was only on paper and in practice the D only had 4x .50's correct?
One more question for you, why would they go in favor of the 20mm Hispano instead of the 37mm Oldsmobile cannon? Was the Hispano that much better than the larger Oldsmobile cannon?
ack-ack
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Originally posted by Ack-Ack
OK, so all the design specs that I've seen for the D that showed the default guns package as a 37mm or 23mm and 4x .50 cals was only on paper and in practice the D only had 4x .50's correct?
One more question for you, why would they go in favor of the 20mm Hispano instead of the 37mm Oldsmobile cannon? Was the Hispano that much better than the larger Oldsmobile cannon?
ack-ack
Yep the D was supposed to get that cannon but it never did.
I'm guessing they went with the 20mm for the rate of fire. The 37mm probably wouldn't have been too effective in air to air, with the slow rate of fire and velocity.
Seems like I recall P39 drivers who had that gun, saying they could see it almost drop out of the end of the barrel some times.
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Originally posted by Ack-Ack
One more question for you, why would they go in favor of the 20mm Hispano instead of the 37mm Oldsmobile cannon? Was the Hispano that much better than the larger Oldsmobile cannon?
ack-ack
Everyone I talked to who flew anything with the 37MM said it sucked, the velocity was low, the trajectory was terrible, and it jammed constantly. The 20MM was light years ahead.
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fly a yak9t and they have the 37mm...maybe not same company, but same trajectory and such...what ive read about that was that the 37mm was unreliable and was succeptable to malfunction more than the 20mm.
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Originally posted by Ack-Ack
OK, so all the design specs that I've seen for the D that showed the default guns package as a 37mm or 23mm and 4x .50 cals was only on paper and in practice the D only had 4x .50's correct?
One more question for you, why would they go in favor of the 20mm Hispano instead of the 37mm Oldsmobile cannon? Was the Hispano that much better than the larger Oldsmobile cannon?
ack-ack
US policy makers didnt buy into needing a cannon of a size suitable for platforming on a plane between ww1 and ww2. When the war in europe finally caused a concern they were behind the curve. If I remember correctly that particular cannon was a knock off of an older french gun, and wasnt up to par with the contempary technology. I think there were supply issues too.
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Akak, if you have Bodie's book, there are a couple of pages devoted to the politics of finding a cannon armament for US planes. Ch 8 Weapons of War. (Took me a bit to remember where I had gotten my fuzzy details from :) )
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Originally posted by killnu
fly a yak9t and they have the 37mm...maybe not same company, but same trajectory and such...what ive read about that was that the 37mm was unreliable and was succeptable to malfunction more than the 20mm.
Balderdash. The NS-37 on the Yak-9T has a vastly higher muzzle velocity than the Olds 37mm. Saying they are the same is like saying the Hispano is the same as the MG/FF on the Bf109E ot the Type 99 Model 1s on the A6M2 because all three guns are 20mm.
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Hi Ack-Ack,
>One more question for you, why would they go in favor of the 20mm Hispano instead of the 37mm Oldsmobile cannon? Was the Hispano that much better than the larger Oldsmobile cannon?
Have a look at Tony's site:
http://www.quarry.nildram.co.uk/WW2guneffect.htm
Based on Tony'd data, I calculated the Hispano II's total firepower as 1.06 MW (kinetic and chemical energy at the muzzle), while the 37 mm M4 had only 0.91 MW.
The Hispano cannon only weighed 50 kg compared to 91 kg for the M4, and while I don't know the total cartridge weight for the 37x145R rounds, I suppose an equivalent ammunition supply would have been roughly twice as heavy as the Hispano's, too ... only that the M4 didn't use ammunition belts but a mechanized feed that was yet heavier and only held a limited number of rounds so that it would be impossible to actually load an equivalent supply of 37 mm shells.
So the use of the Hispano cannon appears to be a very good decision.
On the other hand, one has to wonder why only one Hispano was used.
Historical battery:
- 4x .50 Browning M2 - 500 rpg - 336 kg - 100% firepower (38 s of fire)
- 1x Hispano II - 150 rpg - 87 kg - 94% firepower (15 s of fire)
- Total: 423 kg 194% firepower
Cannon-only battery:
- 2x Hispano II - 281 rpg - 238 kg - 187% firepower (28 s of fire)
That would have yielded about the same firepower at just 56% of the weight. In fact, you could have mounted a third Hispano for a substantial firepower increase and still have saved a few kilograms. The nose of the P-38 certainly should have offered enough space!
Regards,
Henning (HoHun)
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Originally posted by HoHun
- 2x Hispano II - 281 rpg - 238 kg - 187% firepower (28 s of fire)
That would have yielded about the same firepower at just 56% of the weight. In fact, you could have mounted a third Hispano for a substantial firepower increase and still have saved a few kilograms. The nose of the P-38 certainly should have offered enough space!
(http://479th.jasminemarie.com/images/2-20mm.jpg)
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Hi Murdr,
>http://479th.jasminemarie.com/images/2-20mm.jpg
Wow! :-) Great gun platform! Is there a story behind the photograph? Why didn't they build all P-38s that way?
Regards,
Henning (HoHun)
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sorry karnak, didnt mean to get your panties in a bunch there. point i was tryin to make, yak9t has a 37mm....fly it and you will see what it is like. im thinking the trajectory of the yaks 37mm and the olds 37mm can not be that much different. and if the olds 37mm rof is any slower than the yaks 37mm, guess you would need a sun dial to time it. other than that, like my post said, from what ive read the olds 37mm was succeptable to malfuntion and therefore not as reliable as the 20mm.
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Hi Killnu,
>im thinking the trajectory of the yaks 37mm and the olds 37mm can not be that much different. and if the olds 37mm rof is any slower than the yaks 37mm, guess you would need a sun dial to time it.
The Yak's NS37 had 230% the firepower, 150% the muzzle velocity and 160% the rate of fire of the P-39's M4 cannon.
Regards,
Henning (HoHun)
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Originally posted by HoHun
Hi Murdr,
>http://479th.jasminemarie.com/images/2-20mm.jpg
Wow! :-) Great gun platform! Is there a story behind the photograph? Why didn't they build all P-38s that way?
Regards,
Henning (HoHun)
Its one of a few arrangments they tested for the XP-49 program using modified P-38s (G-5-LO in the photo). The XP-49 program was abandoned after problems getting the envisioned powerplant forced a downgrade that only provided marginal performance over the original P-38.
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NS37 had 230% the firepower, 150% the muzzle velocity and 160% the rate of fire of the P-39's M4 cannon.
firepower...37mm doesnt equal 37mm? not sure what you mean by firepower i guess...when i think of firepower, i think of size of the projectile, maybe i am all wrong.
increase in muzzle velocity is going to change the trajectory? i really not sure of that. i can see where it would, but does it change it that much?
so the NS37 was more reliable than the olds 37mm because of all the stuff you posted?
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I guess it simply means the Russian NS-37 37mm was a much more superior heavy cannon than the M4 37mm initially equipped on the P-39s. While a direct comparison would be out of context the Soviets seem to very much like their P-39s equipped with M4.
As for why the P-38 didn't use more Hizookas and less .50s.. well.. maybe its just a 'US thing'? I seem to recall most US pilots were much more accustomed to multiple .50s and didn't really like the setups with one or two cannons as major firepower. Maybe that weighed to be a much larger problem than the actual difficulty of producing such a platform...?
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killnu,
Why do you think the trajectory of the Hispano is so much better than that of the MG/FF? They're both 20mm cannons after all.
20 X 80RB MG/FF 20mm cannon: 600 m/sec muzzle velocity
20 X 110 HS404 20mm cannon: 880 m/sec muzzle velocity
37 X 145R M4 37mm cannon: 610 m/sec muzzle velocity
37 X 195 NS-37 37mm cannon: 900 m/sec muzzle velocity
The faster it is going when it leaves the barrel the flater the trajectory will be. Rate of deceleration will depend on the drag coefficient of the round, but the initial flight trajectory is dependant on muzzle velocity. Take the Bf109E-4 or A6M2 and do deflection shots against the drones offline and then do deflection shots with the Spitfire Mk V or Hurricane Mk IIc. The Bf109E has MG/FF cannon and the Spit and Hurri have Hispano Mk II (HS404) cannon. That'll give you an idea of how different the trajectories are based on about a 300 m/sec muzzle velocity difference.
As to the firepower, that depends on the explosive content of the round. It varried a lot within a given diameter depending on the design of the shells. The Germans in particular were good at loading a lot more explosive into a round.
What we are getting at is that if you base the M4 37mm's possible behavior on the NS-37 of the YAK-9T you are going to be very disappointed. It will be much harder to hit with and will do less damage when it does.
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ok, got it. but was it more reliable than M4? or they both as succeptable to jamming, etc...? what i read about the P38 not using the Old37mm was that it was unreliable. I made the obviously incorrect assumption that the yaks 37mm was similiar to the olds37mm in more ways than it is.
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The NS-37 was used fairly widely by the Soviets. I don't know how reliable it was, but the usage suggests that it was at least fairly reliable.
I would like to have the Il-2 armed with two NS-37 cannon and loaded with AP ammo. It would be a much better tank killer than our current 23mm VYa armed Il-2.