FLYBOYJ
"THE GREAT GAZOO"
Yep - by putting 90 pounds of ballast in the nose!
Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained)
- Thread starter greybeard
- Start date
Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules
Yep - by putting 90 pounds of ballast in the nose!
Thumpalumpacus
Major
That sounds like an angry sergeant in maintenance detailing his sad-sack to digging and filling a hole, lol.
(Never saw that, just heard the old-timers talk about it.)
I was joking when I suggested that
What was it about Bell that made them so "special". North American managed to make one of the foremost fighters, one of the foremost trainers and one of the most versatile twin engined planes in the whole war, did they ever have an issue that plagued these planes from start to finish without a cure coming from them and not someone else? As far as I can see they just said "yes sir, but you need to consider this or limit that, and put it in the pilots notes" they didnt pretend that a P-51 with maximum fuel was anything other than a potential accident on take off, but between client and manufacturer they made it work.
FLYBOYJ
"THE GREAT GAZOO"
Bell was successful with helicopters because of the very talented Arthur Young. Personally after all the SNAFUs encountered during WW2 and with other manufacturers surpassing Bell's ability to design and produce modern fighter aircraft, I think it was a smart business move to concentrate on helicopters as the core business. Larry Bell died in 1956 IIRC but the helicopter division flourished until it was sold to Textron in 1960. By then it was an entirely different company.
I read years ago in a link I can no longer find that RAF 601 squadron had a Russian aviation expert attached to them when they were using the P-39. So when the P-39 arrived in Russia they had a good idea of what to do to make it a success. (Maybe
Dimlee
can help with this). Did Bell have their own test pilots or any real feedback from pilots in the field? I just cant understand why this CoG issue went on throughout the war, with Bell designing a replacement for the P-39 and designing in the same ffing problem.
Dimlee
can help with this). Did Bell have their own test pilots or any real feedback from pilots in the field? I just cant understand why this CoG issue went on throughout the war, with Bell designing a replacement for the P-39 and designing in the same ffing problem.
Thumpalumpacus
Major
All very true, their fixed-wing business was, I think, killed in large part by the -39/-63 experiences USAAF had during the war. I was just trying to be very accurate with that edit, and acknowledging their work (which was obviously good) in rotary-wing stuff.
Just like their airplanes, Bell was itself a pretty quirky company, so far as I've read. "Quirky" and military don't often play well together.
FLYBOYJ
"THE GREAT GAZOO"
I read years ago in a link I can no longer find that RAF 601 squadron had a Russian aviation expert attached to them when they were using the P-39. So when the P-39 arrived in Russia they had a good idea of what to do to make it a success. (Maybe
I think the Soviets did everything they could to make the P-39 a formidable weapon. I also think the environment the Soviets operated the P-39 in was the perfect niche for this aircraft. Agree with our "Expert" friend, "remove the wing guns and the IFF (with the Soviets not having a requirement for IFF, a little crazy if you ask me!) Earlier I showed some calculations that with the IFF removed and the radios moved forward, you're going to get the CG within the middle range with ammo depleted and 1/4 full tanks, even further forward when full of fuel and fully armed. The Soviets knew the P-39 (and P-63) was tail heavy as documented, so I think they might have done other things to get C/G to move more forward (ballast?)
As far as the AAF - in the Pacific the P-39 (along with the P-40) was doomed to be pushed aside by the P-38, a weapon the 5th AF General Kenny made his primary acquisition. In The Med and Europe, we saw how quickly the P-39 was placed in secondary roles once other aircraft came on scene, so I think the AAF knew of these deficiencies and just operated around them.
We do know a lot of P-39s were used in training, many were also lost (like other aircraft of the day) but that's naturally going to happen in a training environment.
I find it funny that after all the controversy with the P-39, folks at Bell STILL continued to ignore lessons learned when they were developing the P-63.
As well documented, some pilots loved the aircraft many hated it. It's reputation wasn't set by a few disgruntled pilots, every WW2 fighter pilot I ever met who flew the aircraft did not have favorable things to say about it, at least two that I can recall "hated it." Instead of trying to theorize what "should have" been done, or what "could have" I think more emphasis should be placed on how it was operated, where it succeeded and where it failed. Historical facts rather than armchair engineering.
Thumpalumpacus
Major
Kenney was very astute, one of the best USAAF generals in my humble opinion. He wasn't beholden to gear -- he rejected the A-26 in favor of more B-25s -- so when he said some gear was crap, I'm inclined to pay the hell attention.
One thing I picked up from reading various "bits" was that on the eastern front rate of roll was prized over rate of turn. If conflict starts at a lower altitude and they all descend to the ground then rate of roll is more important and ditching wing guns is one of the few things you can do to improve it.
wuzak
Captain
The P-38 was supposed to get the 37mm, but they switched to the 20mm and never considered going back.
Shortround6
Major General
"The P-39C may have been ordered in August 1939 but the first production delivery was in January 1941 and it suffered substantial weight gain during production like the P-400. The weight specified on the contract was substantially lower, more like the original P-400 weight."
And why the weight gain?
You are the one claiming the British started specifying all manor of extraneous stuff to get the weight up and the Performance down AFTER The BoB in order to get out of a cash contract.
YP-39, was first flown on September 13, 1940, same day the USAAC ordered the P-39Ds. One source says "Empty and normal loaded weights rose to 5042 pounds and 7000 pounds, respectively. "
Bell simply could not deliver a working (or read viable) combat aircraft at the weights specified in the contract. Yet you want to blame the British.
" Okay, in detail (AHT) the P-39D weighed 5523lbs empty and grossed 7690lbs. The P-400 weighed 5550lbs empty and grossed 7700lbs even. You can look for the 10lb difference if you like."
If that is what you consider "detail" it is no wonder these threads have dragged out so long.
I will try to be plainer.
Please list all of the items that the British specified that ran the weight up over and above the weights for the YP-39 or P-39C.
Items that the USAAC did not specify for either the P-39C or the P-39D so that we can see exactly how the British were trying to get out of the contract.
Don't bother just copying the gross weights. I am looking the the specific item or items of equipment that ran the weight up that weren't needed for a successful combat fighter of the time.
You made the claim the British ran the weight up unnecessarily. Show us how.
And why the weight gain?
You are the one claiming the British started specifying all manor of extraneous stuff to get the weight up and the Performance down AFTER The BoB in order to get out of a cash contract.
YP-39, was first flown on September 13, 1940, same day the USAAC ordered the P-39Ds. One source says "Empty and normal loaded weights rose to 5042 pounds and 7000 pounds, respectively. "
Bell simply could not deliver a working (or read viable) combat aircraft at the weights specified in the contract. Yet you want to blame the British.
" Okay, in detail (AHT) the P-39D weighed 5523lbs empty and grossed 7690lbs. The P-400 weighed 5550lbs empty and grossed 7700lbs even. You can look for the 10lb difference if you like."
If that is what you consider "detail" it is no wonder these threads have dragged out so long.
I will try to be plainer.
Please list all of the items that the British specified that ran the weight up over and above the weights for the YP-39 or P-39C.
Items that the USAAC did not specify for either the P-39C or the P-39D so that we can see exactly how the British were trying to get out of the contract.
Don't bother just copying the gross weights. I am looking the the specific item or items of equipment that ran the weight up that weren't needed for a successful combat fighter of the time.
You made the claim the British ran the weight up unnecessarily. Show us how.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
It's almost funny how various air forces had their obsessions: The RLM wanted everything to be a dive-bomber, the USAAC/USAAF wanted everything to have a 37mm cannon and so on...
wuzak
Captain
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
Messerschmitt altered the Me262's wings to address CoG issues, so that might be one avenue to explore.
The British just wanted to screw up anything that came from the USA, its a historical fact, as can be seen from the P-40 and P-51. Actually it is utter bollocks. The British were doing R&D on the P-39 in a way they were never required to on the P-40 and P-51 which pretty much did what was said on the tin. This line of discussion from the expert holds no water at all.
Thumpalumpacus
Major
The British had as much experience in air combat as anyone in the world, in 1941. Their not liking the -39 speaks volumes when we keep this in mind. After the BoB they knew what they needed, and the -39 was not it. They knew bullshit when they saw it.
That the VVS got more out of it in their combat milieu was great. Goes to show how operational needs and circumstances can affect the utility of gear. It also shows how narrow was the utility of the -39, to me.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
The Soviets were in dire need of anything they could get their hands on in the first years of the war.
I am certain that if they were given Brewster Buffalos or Blackburn Rocs, they would have made those work, too.
I am certain that if they were given Brewster Buffalos or Blackburn Rocs, they would have made those work, too.
ThomasP
Senior Master Sergeant
P-39 Maximum Range - internal fuel with fuel for WUTO & climb to 10,000 ft not available for range:
P-39D____600 miles at 232 mph TAS at 10,000 ft___2600 rpm at 26"Hg__120 USgal
P-39N____360 miles at 250 mph TAS at 10,000 ft___2650 rpm at 26"Hg___87 USgal
P-39Q____530 miles at 240 mph TAS at 10,000 ft___2650 rpm at 26"Hg__120 USgal
As to the CG issue:
I may be misremembering, but I believe the P-39N model incorporated changes to alleviate the out-of-CG problem due to the expenditure of the nose gun ammo. What the exact changes were I do not know.
As to the change of/removal of armour:
As to the weight of the radio equipment in the aft compartment, and possible movement of it to correct CG:
P-39D____600 miles at 232 mph TAS at 10,000 ft___2600 rpm at 26"Hg__120 USgal
P-39N____360 miles at 250 mph TAS at 10,000 ft___2650 rpm at 26"Hg___87 USgal
P-39Q____530 miles at 240 mph TAS at 10,000 ft___2650 rpm at 26"Hg__120 USgal
As to the CG issue:
I may be misremembering, but I believe the P-39N model incorporated changes to alleviate the out-of-CG problem due to the expenditure of the nose gun ammo. What the exact changes were I do not know.
As to the change of/removal of armour:
As to the weight of the radio equipment in the aft compartment, and possible movement of it to correct CG:
FLYBOYJ
"THE GREAT GAZOO"
I believe a catch box was installed to maintain the shell casings from the cannon
wuzak
Captain
So the IFF components ("pipsqueak") amounted to only a few pounds?
