Most Overrated aircraft of WWII.....? (1 Viewer)

[Navalwarrior]

Post-war, as transonic wind tunnels were still new tech, a P-51 was modified for high-Mach number research.

The NACA engineers and technicians carefully cleaned up the aircraft, including removing the propeller, packed it with instrumentation, and towed as high as possible behind a lightly-loaded B-29 or B-50. See http://naca.central.cranfield.ac.uk/reports/1948/naca-report-916.pdf

Mr Nissen then dived towards the ground.

Resp:
My father went to work for NACA shortly after WWII, where he evaluated 'wind tunnel' (the Govt just recently dismantled their wooden wind tunnel [that was in use prior?/during WWII]@ 2016) tests on various aircraft. I remember that NACA had several Bell Airacobras (or Kingcobras) that they installed swept wings (likely removed the propeller, but he didn't mention that) on them to do high speed evaluations, al la F-86, etc.. He also worked on the X-15. He transferred to NASA (a division of NACA at the time) in 1961, where he headed Structural Testing for every part/assembly prior to space flight, retiring in 1981.

 

[wuzak]

Well, it flew with a propeller

Bell P-63 Kingcobra - Wikipedia

 

[Navalwarrior]

Well, it flew with a propeller

View attachment 509515

Bell P-63 Kingcobra - Wikipedia

Resp:
Thanks!
Any idea what the minimum speed would be to maintain lift with the swept wing? Certainly would have to be greater than the conventional wing. I wonder what the maximum speed would have been.

 

[wuzak]

You can see the leading edge slats, which I believe were for low speed handling.

 

[Shortround6]

Wiki says the main landing gear was fixed, only the nose gear retracted so max speed is kind of a moot question. The experiments were to explore low speed stall and handling so max speed was not of interest.

 

[Navalwarrior]

You can see the leading edge slats, which I believe were for low speed handling.

Resp:
I just read that an NACA employee named Robert Gilruth found and fixed some flaws in early Mark Spitfire's. And from that point the British assigned a team to him for the rest of the war. Each time Gilruth made a discovery or developed an innovation, it was forwarded back to Briain where it was incorporated into aircraft built there.

 

[tomo pauk]

Resp:
I just read that an NACA employee named Robert Gilruth found and fixed some flaws in early Mark Spitfire's. And from that point the British assigned a team to him for the rest of the war. Each time Gilruth made a discovery or developed an innovation, it was forwarded back to Briain where it was incorporated into aircraft built there.

Interesting. Do you have some link to the source of the information?

 

[Navalwarrior]

Interesting. Do you have some link to the source of the information?

Redo:
Book: Flight, My Life in Mission Control, by Chris Kraft, ISBN 0-525-9457-7, pub 2001

 

[wuzak]

Resp:
I just read that an NACA employee named Robert Gilruth found and fixed some flaws in early Mark Spitfire's. And from that point the British assigned a team to him for the rest of the war. Each time Gilruth made a discovery or developed an innovation, it was forwarded back to Briain where it was incorporated into aircraft built there.

And what flaws did he fix?

 

[fubar57]

And what flaws did he fix?

Probably not much as it isn't mentioned in his NASA bio...
https://history.nasa.gov/naca/bio.html
A large bio
https://www.aem.umn.edu/info/history/gilruth-robert.pdf
Or the all important Wiki
Robert R. Gilruth - Wikipedia

 

[wuzak]

Doesn't appear to be any mention of the Spitfire or Supermarine in any of those.

It appears that the thing which the British were interested in was a reprot he wrote: NACA Report R755, Requirements for Satisfactory Flying Qualities of an Airplane

Which was not specific to the Spitfire.

 

[Navalwarrior]

Doesn't appear to be any mention of the Spitfire or Supermarine in any of those.

It appears that the thing which the British were interested in was a reprot he wrote: NACA Report R755, Requirements for Satisfactory Flying Qualities of an Airplane

Which was not specific to the Spitfire.

And what flaws did he fix?

Resp:
The book didn't say, but I suspect they were related to aerodynamics . . .since they had access to a wind tunnel.
Cont:
The British were interested enough to send/assign a team to work with NACA during WWII.

 

[fastmongrel]

As he didn't start work at NACA till 1937 and didn't start working with wind tunnels till 1939 what influence could he have had on early Spits. What is the earliest date he could conceivably have even seen let alone tested a Spit.

 

[fubar57]

https://www.aerosociety.com/media/4953/the-aerodynamics-of-the-spitfire.pdf

 

[Zipper730]

Well I voted the P-51D as well. It was a great aircraft dont take me wrong but she was not all she was cracked up to be. One on one there were many aircraft that were just as good or better but she gets all the attention.

What other designs would be comparable? I'd guess the P-38 with dive-recovery flaps and P-47N?

 

[Navalwarrior]

As he didn't start work at NACA till 1937 and didn't start working with wind tunnels till 1939 what influence could he have had on early Spits. What is the earliest date he could conceivably have even seen let alone tested a Spit.

Resp:
Taken from an obituary of 'Robert R Gilruth' by Christopher C Kraft, Jr, 2000, nap.edu
In late 1937, Gilruth replaced Hartley Goule (after having been at NACA for 6 mos) as the engineer who flew w/ the test pilots. The purpose of the project was to determine quantities criteria for flying and handling qualities of airplanes. Gilruth became the flying quality expert at Langley.
As a result of the project Gilruth wrote a report titled "Requirements for Satisfactory Flying Qualities of Airplanes," which abstained from pilot jargon and put numbers to the qualities that made an airplane's characteristics good or bad. For the first time Gilruth used his concept of "stick force per g", which compares the pilot's actions to the airplane's reactions. Later when WWII was raging, the British were so enamored with Gilruth's findings they sent a team of people to consult with him in 1943. (Note that this source did not specifically mention 'Spitfire' while the other one did.

 

[wuzak]

Resp:
Taken from an obituary of 'Robert R Gilruth' by Christopher C Kraft, Jr, 2000, nap.edu
In late 1937, Gilruth replaced Hartley Goule (after having been at NACA for 6 mos) as the engineer who flew w/ the test pilots. The purpose of the project was to determine quantities criteria for flying and handling qualities of airplanes. Gilruth became the flying quality expert at Langley.
As a result of the project Gilruth wrote a report titled "Requirements for Satisfactory Flying Qualities of Airplanes," which abstained from pilot jargon and put numbers to the qualities that made an airplane's characteristics good or bad. For the first time Gilruth used his concept of "stick force per g", which compares the pilot's actions to the airplane's reactions. Later when WWII was raging, the British were so enamored with Gilruth's findings they sent a team of people to consult with him in 1943. (Note that this source did not specifically mention 'Spitfire' while the other one did.

The British started working with Gilruth in 1943. Which is 7 years after the Spitfire first flew. The V, VIII, IX, XI and XII were in production (maybe the X as well), the XIV was under development (VIIIG).

All these used the original wing section, though improved structurally, variations on the cooling systems introduced with the I in 1938, and largely unchanged rear fuselage, cockpit, etc.

The Spitfire 21 was under development since early in the war - 1940 or 1941 - but kept getting pushed back because of priorities for improving existing models. I believe the 21 wing had the same section as before, but had a much stronger structure and slightly different plan form.

How exactly did he fix anything on the Spitfire?

And the report he wrote was about the quantitative evaluation of the handling of aircraft, rather than qualitative evaluation.

Applying these techniques (presumably to all British aircraft) did not mean anything needed to be, or was, changed.

 

[wuzak]

https://www.aerosociety.com/media/4953/the-aerodynamics-of-the-spitfire.pdf

Funnily enough, Gilruth doesn't appear in that document.

 

[fubar57]

Zactly

 

[GrauGeist]

What other designs would be comparable? I'd guess the P-38 with dive-recovery flaps and P-47N?

The IJN's N1K was a deadly adversary against the P-51D and USN types.