Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained)

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Weight and rate of climb are directly related when engine power remains constant.

It isnt a question of just weight, it is thrust lift drag etc.
One Ex to another: t'aint that simple, lad. pbehn's pesky variables all add into the equation. Two engines of the same horsepower don't necessarily produce the same thrust unless they have identical props and superchargers rigged identically. Different marks of the same airframe almost certainly will not have identical drag coefficients due to different armament, antenna, and various other details. I could go on and on, but it's like conversing with a brick wall.

 
It is a complete waste of time, to improve the performance of the P-39 to get it to do 400MPH one mod was to change the exhausts to be in the direction of airflow, the Spitfires fish tail exhausts increased speed by about 10MPH with a slight increase in climb rate, so an increase in performance with no increase in power, all this has been posted here on this thread.
 
Weight and rate of climb are directly related when engine power remains constant.
With regard to Thumpalumpacus post below, engine power did not remain constant. The problem with the Allisson engine was it ran out of lungs at lower altitudes than others, but its power was changed by use of different fuels and gear ratios, you often quote this in your arguments. The power of the Merlin changed with use of different fuels which didnt increase weight, as well as different superchargers which did. The Merlin increased from circa 1,000BHP to circa 2,000BHP in 5 years, so 200BHP per year and airframes had to adjust to it and make use of it. The Hurricane MkII was 7 inches longer than a MkI. What do you do about an engine 7 inches longer in a P-39? Every small change in the engine requires almost a completely new airframe to be designed. Without these changes the P-51 would never have been an escort fighter with a Merlin engine, how would it perform with 1000BHP max?



 
Not proven wrong about any of those. Not wasting time proving them again.
You haven't proven many or indeed any of them.

Saying they are wrong is not proving they are wrong.

WHEN did the British specify the "extra" stuff to get out of the contract?
Which date/s or contract talks?
Why didn't Bell negotiate a lower performance standard if the British added weight?
Instead Bell spent weeks modifying the 2nd production airframe to a point where it could make the lower margin of the speed band specified in the contract.
Bell KNEW the P-400 didn't have a hope of meeting the contract specs weeks before the test flights. And yet it is the fault of the British?????
Bell had sold the French a plane that wouldn't meet the specs and the British got stuck with the contract. They had 3 opportunities, yet the original performance specs stood.

You have said the stuff the British added was useless.
As proof you trot out that the IFF wasn't needed in NG in 1942. Without a time machine what has that got to do with what the British needed in 1940-41 when fighting in British air space or over the Channel?
Cockpit heater is useless????
Two are redundant, were the British ever offered the system using the hot air from the radiator duct?
Self sealing fuel tanks are useless?

You have one quote from a page in AHT saying the .30 cal guns had an effective range 200yds and turn that into the .30 cal guns were useless. I do like AHT but it is not infallible and I have shown there are several mistakes on that page. I would also note that the British did NOT rip the .30 cal guns out of the early P-40s and depend on the two cowl .50s.

A bit more proof that A, .30 cal guns were useless in general and B, that the British could have known this in 1940 and early 1941,
At the time of the 2nd specification talks with Bell (Jan 1941) the British had gotten done with the BoB where over 99% of the fighting was done with .30/.303 guns. At that time the British were still arming the vast majority of their fighters with .303 guns including planning to fit 12 into the Hurricane II and the Typhoon.
But somehow the British are "tricking" Bell by keeping the four wing guns that Bell agreed to put in for the French?

Repeating wrong information many times does not make it true.

You are the one claiming much of what we know about the P-39 is wrong and yet you offer little more than conjecture or unproven claims.
 
I just read recently that the requirement for IFF was a direct result of the "Battle of Barking Creek" 6 Sept 1939


In 2003, Patrick Bishop wrote that the incident exposed the inadequacies of RAF radar and identification procedures, leading to their being greatly improved by the time of the Battle of Britain, a view echoed in a 2012 publication by Philip Kaplan.[11][5]
 
Since no one took my .30 armed Airacobra idea seriously... *sniff*



1). No matter what anyone else says, I agree with SaparotRob I'm learning a lot and enjoying it fully.

2). P-39 Expert is a master troll. I've been around message boards too many years (read decades) not to recognize the traits of one. He may claim he's not, but if it walks like a duck...

I'm not saying that's a bad thing mind you, see number one (1) above.
 
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Not proven wrong about any of those. Not wasting time proving them again.

They have ALL been proven wrong. You have made incorrect statements again and again and, when called on it, you deflect or change the entire argument. Just because you refuse to read or accept evidence does not mean that the evidence is invalid or that the proof is insufficient. You keep trotting out your own "proof" but most is centred in opinion not in fact. You've been asked for facts and to confirm information...and every time you have refused to answer.

In the spirit of the Oscars, for excellence in film making, I hereby award you a Bert for supreme trollery.



Like any good troll, Bert is stumbling forward, constantly reaching out to clutch at any straws that perpetuate his world view regardless of the facts. His left eye is closed, connoting an inability to see everything that is in front of him, and a focus solely on a partial view of the world.
 
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Okay. I've stripped out the padding from both ends of the code. Now to 'figger out the middle. It's gonna' take some time. I got the "mit" part though.
 

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