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Donald S. Mitchell's 1946 Goodyear Racer flying wing design

Stargazer2006

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Excerpts from a 1946 brochure whereby glider designer Don Mitchell hoped to raise an interest and attract some financing for a revolutionary flying wing racer design to be submitted to the “Goodyear Trophy Race” competition.
Mitchell is especially known for his work with Hawley Bowlus on the Bumble Bee/Dragonfly design, his Nimbus gliders of the 1950s and his Mitchell Wing (B-10, A-10) powered hang gliders and Super Wing (U-2) ultralight powered glider.

index.php




The National Air Races held annually at Cleveland, Ohio are a thrilling air show a valuable source of aircraft improvement.
In 1946, to encourage the design and development of light aircraft the Goodyear Tire & Rubber Company created and sponsored the “Goodyear Trophy Race” as part of the National Air Races.
This booklet is submitted in a sincere effort to obtain a sponsor and co-owner for the racer herein described. It is a project that vigorously breaks away from the exhausted conventional design.
It is not, however, a flight of the imagination, but rather one based on sound advanced aerodynamics with practical data proving this type of aircraft is without parallel.
It is a project that not only will admirably perform its main purpose of winning races, but one that can be used as a nucleus for the design of cheap, safe, high performance light aircraft, military pilotless jet drones, target ships, and practical roadable airplanes.
The reader will recognize within these covers the outline of a project that will have an immediate satisfaction and profit to the sponsor, designer, and to the aircraft industry as a whole.

Donald S. Mitchell



WHY THIS RACER?

Because,
. . . It is ultra modern and sensational in appearance;
. . . It has sparkling, exciting performance; it has the ability to smash records;
. . . It has eye appeal and fires the imagin-ation - qualities necessary for wide-spread and
lasting publicity;
. . . It has the “New Look” in aviation;
. . . It has terrific potentialities besides racing;
. . . It will be the first flying wing to compete in the National Air Races;
. . . It has a basic control method destined to bring a new era to aviation.

Winning races is the prime purpose of a racing airplane. THIS flying wing will do that -- and much more.



SPECIFICATIONS Top Speed 245 M.P.H.
Landing Speed 55 M.P.H.
Engine Continental C-85
85 H.P. at 2570 R.P.M.
Pusher Installation
Span 18 feet
Area 72 Sq. Feet
Sweepback 40 Degrees
Total length 9 Feet
Nacelle height 43 Inches
Weight empty 400 lbs. **
Ballast 100 lbs. **
Landing Gear Tandem (Two Goodyear tires and wheels- 5.00-5)
Brake on rear wheel
No dihedral. No wing twist.

** 500 lbs. minimum weight empty required for Goodyear Race.




For the full contents of the brochure, see this page:
http://www.twitt.org/GoodyearRacer.html
 

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Retrofit

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Unfortunatly for Don Mitchell, The PRPA (Professional Race Pilots Association) rules prohibited flying wings (as well as prone pilot configuration) in its 1947 Formula One design specifications.
 

cluttonfred

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The timing is interesting...I wonder if the "no flying wings" provision was introduced in response to Don Mitchell's proposal?
 

Grey Havoc

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cluttonfred said:
The timing is interesting...I wonder if the "no flying wings" provision was introduced in response to Don Mitchell's proposal?

Quite likely.
 

Wahubna

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Retrofit said:
Unfortunatly for Don Mitchell, The PRPA (Professional Race Pilots Association) rules prohibited flying wings (as well as prone pilot configuration) in its 1947 Formula One design specifications.

I do not remember reading an explicit rule in the current International Formula 1 rules prohibiting tail-less configurations...I did model & analyze a tail-less design but for 'other' reasons going tail-less in F1 is a bear...

http://www.if1airracing.com/images/Documents/IF1_Technical_Rules_Rev2011.pdf
 

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After 41 years involvement in all aspects of Formula One except actually flying the things, I could not stay out of this one! I have written quite a few of the rules over the years and they are still using my drawings in the current technical rules referenced above. I do not have access to my files which include the original PRPA rules from 1947, but as I recall they did not specifically exclude flying wings. What they did require however was that proposed designs be approved by the Technical Committee. Something this radical would not have survived the review process. At the time Northrop was the only company successfully working with flying wings and even for them stability was a challenge. Flying closely in the wake of seven other aircraft is particularly difficult.

Current rules do not exclude tailless aircraft and Jim Miller's original "Texas Gem" 1973? (http://www.secretprojects.co.uk/forum/index.php/topic,4015.msg245433.html#msg245433) used a flap on the top of a ducted prop for elevator control, but was otherwise a flying wing. This design did not work well and Jim reverted to a Tee tail with separate elevator. International Formula One does specifically exclude prone pilots and controls the overall fuselage height. The number in the rule height rule was set by Jim Miller's "Pushy Cat" to avoid excluding him and to limit the degree of recline permitted. The vision rules are also a major determinant on the configuration.
 

Stargazer2006

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BillRo said:
After 41 years involvement in all aspects of Formula One except actually flying the things, I could not stay out of this one! I have written quite a few of the rules over the years and they are still using my drawings in the current technical rules referenced above. I do not have access to my files which include the original PRPA rules from 1947, but as I recall they did not specifically exclude flying wings. What they did require however was that proposed designs be approved by the Technical Committee. Something this radical would not have survived the review process. At the time Northrop was the only company successfully working with flying wings and even for them stability was a challenge. Flying closely in the wake of seven other aircraft is particularly difficult.

Current rules do not exclude tailless aircraft and Jim Miller's original "Texas Gem" 1973? (http://www.secretprojects.co.uk/forum/index.php/topic,4015.msg245433.html#msg245433) used a flap on the top of a ducted prop for elevator control, but was otherwise a flying wing. This design did not work well and Jim reverted to a Tee tail with separate elevator. International Formula One does specifically exclude prone pilots and controls the overall fuselage height. The number in the rule height rule was set by Jim Miller's "Pushy Cat" to avoid excluding him and to limit the degree of recline permitted. The vision rules are also a major determinant on the configuration.

Very, very interesting! Great to have a Formula One insider among our ranks. I'll have to remember this when I have questions about certain obscure racers... ;D

I suppose the aircraft you designate both as the "Pushy Cat" and the "Texas Gem" is the same I have as the JM-2 "Pushy Galore". If so, it did appear in 1973 indeed.
 

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BillRo

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Nice Skyblazer. The gold pusher is Jim's "Texas Gem" in its original configuration; it was then modified with the tee tail. I think that is the one in which Chuck Andrews lost his life. Jim built a stretched 2 place that he sold to Errol Roberson who named it "Puffin". Both were lost at Reno, again due to structural failure.
Jim made two improved versions, his own "Pushy Cat" and another for Bruce Bohannon which was named "Pushy Galore". Bruce raced it then modified it for time-to-climb records with Aeroshell sponsorship. I think that plane is hanging on a hangar wall in Texas. "Pushy" was sold to another pilot who tried to race it but had an engine failure during practice and landed off the airport. The accident tore off the gear and the aircraft has not reappeared.

A side note on pushers. Formula One engines are quite strictly controlled by the rules but are run at up to 4300 rpm and produce perhaps 40% more power than stock. For his climb record attempts Bruce had no such constraints and using nitrous was able to double the engine power. Even with that he could never get a level flight speed above 240/250 m/h, concluding that a pusher prop blade passes through the wing wake twice a revolution and loses efficiency compared with a tractor design. The current 3 mile Reno lap record is 267 m/h, not bad for a blueprinted 100HP Cessna 150 engine.
 

Stargazer2006

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BillRo said:
Nice Skyblazer. The gold pusher is Jim's "Texas Gem" in its original configuration; it was then modified with the tee tail. I think that is the one in which Chuck Andrews lost his life. Jim built a stretched 2 place that he sold to Errol Roberson who named it "Puffin". Both were lost at Reno, again due to structural failure.
Jim made two improved versions, his own "Pushy Cat" and another for Bruce Bohannon which was named "Pushy Galore". Bruce raced it then modified it for time-to-climb records with Aeroshell sponsorship. I think that plane is hanging on a hangar wall in Texas. "Pushy" was sold to another pilot who tried to race it but had an engine failure during practice and landed off the airport. The accident tore off the gear and the aircraft has not reappeared.

A side note on pushers. Formula One engines are quite strictly controlled by the rules but are run at up to 4300 rpm and produce perhaps 40% more power than stock. For his climb record attempts Bruce had no such constraints and using nitrous was able to double the engine power. Even with that he could never get a level flight speed above 240/250 m/h, concluding that a pusher prop blade passes through the wing wake twice a revolution and loses efficiency compared with a tractor design. The current 3 mile Reno lap record is 267 m/h, not bad for a blueprinted 100HP Cessna 150 engine.

Thanks BillRo. I was only aware of two of these aircraft and didn't know there had been four actually. I guess the two-seater later named Puffin is the one that Miller called the GEM-260, a 1984 type which didn't have a duct around the propeller (at least in the photos I've seen of it).
 

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Wahubna

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BillRo said:
Nice Skyblazer. The gold pusher is Jim's "Texas Gem" in its original configuration; it was then modified with the tee tail. I think that is the one in which Chuck Andrews lost his life. Jim built a stretched 2 place that he sold to Errol Roberson who named it "Puffin". Both were lost at Reno, again due to structural failure.
Jim made two improved versions, his own "Pushy Cat" and another for Bruce Bohannon which was named "Pushy Galore". Bruce raced it then modified it for time-to-climb records with Aeroshell sponsorship. I think that plane is hanging on a hangar wall in Texas. "Pushy" was sold to another pilot who tried to race it but had an engine failure during practice and landed off the airport. The accident tore off the gear and the aircraft has not reappeared.

A side note on pushers. Formula One engines are quite strictly controlled by the rules but are run at up to 4300 rpm and produce perhaps 40% more power than stock. For his climb record attempts Bruce had no such constraints and using nitrous was able to double the engine power. Even with that he could never get a level flight speed above 240/250 m/h, concluding that a pusher prop blade passes through the wing wake twice a revolution and loses efficiency compared with a tractor design. The current 3 mile Reno lap record is 267 m/h, not bad for a blueprinted 100HP Cessna 150 engine.

Pushy Galore is in the EAA museum and looking good:
https://www.eaa.org/en/eaa-museum/museum-collection/aircraft-collection-folder/1989-miller-bohannan-jm-2-special-pushy-galore---n189bb

You are absolutely right, pushers do not work better! The tail-less I was exploring was a tractor for that reason but I came across some other issues related to turning pylons. Tail-less is a very interesting and entirely solvable problem today. Lots of literature on the topic, analysis tools, sims, and there still is the small-scale test method! BUT not so hot for F1s...

This past year for F1s was real nice. Wasabi Siren got up to speed, AR-11 (the record setter) was crazy fast, the Gilbert DG-2 was a surprise, and the modified Cassutts were good as usual.
 
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