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I never knew they existed until I read it in a book written by NASA about NACA. NACA is the predecessor to NASA and stands for the National Advisory Council for Aeronautics. Well, before Jet aircraft real got off the ground it turns out they were tasked with developing a supersonic propeller. So, they put in a lot of money and they developed one! They stuck it on an XF-88B and it worked. They reach supersonic with a propeller! But by that time jets have gained their ground, in fact the propeller was placed on a turboprop engine. They theorized that it would be more efficient at low mach speeds than a jet. Well, could we use this efficiently in civilian design maybe a better solution for a supersonic transport or airliner?

<img src="http://www.boeing.com/history/mdc/graphics/histlarg/hist059b.jpg" border=0>

Dear Abby, I joined the Navy to see the world. I've seen it. Now,
how do I get out?

I think you are wrong in this instance. The propeller in that picture is feathered. Nothing working there. Propellers were fitted to the noses of jets when their testing was secret in early development. It was to confuse regular pilots that had not as of yet realised their operational status. That is of course open to discussion because every time I am just positive I am right..............well lets just say I end up being wrong.

By this time tomorrow I shall have gained either a pearage or Westminster Abbey........Nelson

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YGBSM !

MAN THAT ALMOST LOOKS LIKE A F-101 VODOOO.

I WAS WATCHING THE WINGS CHANNEL,HAD IT FOR OVER A YR AND NOW FINALLY WATCHING IT ALL THE TIME.
SAW ALOT OF SHOWS AND HISTORY OF THE FIRST JETS AND WAS REALLY SHOCKED HOW THE US JUST ABOUT GOT PASSED LIKE A BAD BEER IN THE JET RACE!

IF THE AXIS WOULD OF USED THEIR TECH ADVANCES IN AIRCRAFT DESIGN WW2 WOULD OF BEEN A LONGER WAR BY FAR.
EVEN JAPAN HAD A JET FIGTHER AND BOMBER THAT WOULD OF CAUSED A BIG PROBLEM!!!!!!!!

PRESS TO TEST

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\"Live Free Or Die\"

Goose the F-88 laid the groundwork for the F-101 Voodoo.


http://www.wpafb.af.mil/museum/research/fighter/f88.htm

McDonnell XF-88
The XF-88 was designed to fill a USAF requirement for a "Penetration Fighter", a new class of aircraft for long-range escort of USAF bombers. Two XF-88s were ordered (S/N 46-525, 526) in 1946 and the first flight was on 29 October 1948. The XF-88 was underpowered and the second aircraft was modified to the XF-88A by adding afterburning engines which increased its maximum speed to approximately 700 mph. The XF-88A design was used as the basis for the F-101 "Voodoo".
The original XF-88 was modified to XF-88B with the addition of afterburning turbojets and an Allison XT-38A turboprop. The turboprop engine was added to test the feasibility of extending the cruising range of a fighter aircraft. This arrangement, like the XF-81, proved impractical and was never adopted for production.


TYPE Number built/Converted Remarks

XF-88 2 Penetration Ftr.
XF-88A 1 (cv) Mod. XF-88
XF-88B 1 (cv) Turboprop mod.





SPECIFICATIONS (XF-88)
Span: 39 ft. 8 in.
Length: 54 ft. 2 in.
Height: 17 ft. 3 in.
Weight: 18,500 lbs. loaded
Engines: Two Westinghouse J34-WE-13 turbojets of 3,000 lbs. thrust each
Armament: Designed for six 20mm cannons
Crew: One
PERFORMANCE
Maximum speed: 641 mph
Range: 1,737 miles with 734 gallons in internal fuel tanks and two 350 gallon external fuel tip tanks.
Service Ceiling: 36,000 ft




"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

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The only time you have too much fuel is when you're on fire.

the idea was to get on station with jets, then loiter on the prop, and then AB intercept at supersonic speeds with the prop feathered.

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

the "propfan" is as close as we are likely to get to supersonic flight with props
<img src="http://www.aerospaceweb.org/question/propulsion/propfan/propfan2.jpg" border=0>

"We sleep safely in our beds because rough men stand ready in the night to visit violence on those who would harm us". George Orwell

Fighting For Justice With Brains Of Steel !
<img src="http://www.fas.org/man/dod-101/sys/ac/atengun2X.GIF" border=0>

_________________
The only time you have too much fuel is when you're on fire.

[quote]
I never knew they existed until I read it in a book written by NASA about NACA. NACA is the predecessor to NASA and stands for the National Advisory Council for Aeronautics. Well, before Jet aircraft real got off the ground it turns out they were tasked with developing a supersonic propeller. -------

The Force had a F-84 modded with one turboprop. Saw the Wings on it. It was a LOUD SOB. Some claim it went beyond Mach, damn if I know. The Russian Bear bomber with those huge turboprops use to stretch it to Mach. 85 and it was sweptwing. Fastest I ever hit in a turboprop was 415KTAS in a Super P-3B, they could scoot right along.

Navy did build a funky fighter, recip in the front that feathered and a jet kick in the ass. Can't recall the exact type now. Really funny story went around, lead had them all feather and they went scooting by some Admiral's bird inverted.

Only motorgliders to my knowledge (well maybe these single engine turboprops out now might feather inflight), have a single motor that feathers inflight.

Moi has tested my LongEZ infight with the prop stopped, vice it turning for kicks for glide ratios. It decreased my glide ratio by 15% or so. Had to cut the mags to stop the damn prop. I used 5K for a hard deck for a relight. Needed only 120KIAS to turn the prop for a relight. I dumped the nose too. I used 70KIAS at 10K for a standard.

Jack

Maybe I'm miss reading it but I don't think so <BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Unfortunately, this program did not produce results until the mid-fifties when intreset in high-speed propellers had almost disappeared.<b> Three propellers were eventually tested at fight speeds up to slightly above Mach 1 on the XF-88B. </b> By the time theresults were analyzed in 1957, the Subcommittee on Propellers for Aircraft had been disbaned, eliminating a main heading on this subject in the crowning achievement of a difficult and costly project, under the heading "Low-Speed Aerodynamics." <b> Peak effiency of 80 percent had been measure at Mach 0.95 on thin "supersonic" propeller</b>, generally confirming the levels indicated in the Langley High-speed wind tunnel programs <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>
from <u>The High-Speed Frontier, Case history of Four NACA PRograms, 1920-1950</u> by Becker, John



I think this raises the question: If we hadn't invented the jet engine would we still have made high preformance high speed fighters like today?

Dear Abby, I joined the Navy to see the world. I've seen it. Now,
how do I get out?

The XF-84H was also another program designed to test the feasability of a super-sonic propeller driven aircraft. It failed, but the shock-waves of the super-sonic propellers caused a lot of people to vomit uncontrollably. lol

http://www.wpafb.af.mil/museum/research ... /f84sp.htm

Flyboy, while the XF-88B may have gone supersonic with a propeller, I am certain it did NOT go supersonic under turbo-prop propulsion alone. Those two jet engines in the back are what allowed it to do so. Propellers lose so much efficiency at mach, that they can't propell the aircraft fast enough to break the sound barrier. We couldn't accomplish the same fighter performance with prop-jobs as we can with jets, as a result, I think modern propeller fighters would focus on range, maneuverability, verticle climb, and load-carrying capacity, since speed would be limited to about mach .95. (Think P-38 with C-130 engines and a .50 Vulcan. lol)

EzyJack, is this the Navy hybrid you were talking about? The Ryan FR-1 Fireball? (Now isn't <i>that</i> one hell of an inspiring name for the pilots? lol)

http://sfstation.members.easyspace.com/fr-1.htm


A sucking chest wound is life's way of telling you to slow down...

[quote]


EzyJack, is this the Navy hybrid you were talking about? The Ryan FR-1 Fireball? (Now isn't <i>that</i> one hell of an inspiring name for the pilots? lol)

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That's it, ROFL. I knew one fighter jock that flew the Cutlass. Kinda of a far out bird that didn't last long either.

From reports I heard on the F-84 turboprop, it was the loudest sucker they had ever heard.

Late 40s through the late 50s, maybe a tad into the 60s. All sorts of far out birds in test. While I was at NAS Norfolk until 81 or so, they had the damn POGO parked in front of the HQs there. Finally moved it to the Smithsonian and broke the damn canopy when they moved it.

I use to fly into NAS Pax river a little. They always had something going on. Crashed a Hornet one time while I was nearby. Another time think an A-7 went down. Then I got to watch a T-2 doing some ski jump launches.

Real classic was at NAS Oceano, Tomcat on a real IMC day, managed to hit the GCA radar shack. It spun them around and they actually punched out going backwards and lived. SecNav was flying in and they were hustling to clean up the mess.

Army actually ran some Mustangs until 75 or so. They were used as chase birds for the Comanche chopper. Only thing they could use to keep up with it.

Jack

Cheyenne helo. That was the Cheyenne EZ.

<img src="http://www.worldaffairsboard.com/sigs/snipersig.jpg " border=0>

[quote]
Cheyenne helo. That was the Cheyenne EZ.

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Damn I had the C part right. Then and now I still read my AW for data. Not that I recall the part of the Army flying Mustangs for chase. Hell the Navy still had one A-1 flying in ABQ in 81. My good buddy didn't get the gig either to fly it. Mere 2-3 tours in Nam flying Spads.

Jack

the only time I could imagine a propeller plane going supersonic is in a complete nose down dive, with the throttles jammed open! and that will be until it slams into the ground. level flight at supersonic speeds, nah, cant imagine it.

id imagine the propellers would be spinning so fast, they would either

1/have "cavitation" where the airflow breaks away from the surface, and stall the propeller, (cavatation has occured on boat propellers and basically the water boils around the prop face reducing efficiency)

or..

2/ fly apart because of centrifugal forces acting on the propellers.

Also, though most propellers, whether on a DC3 or a P3 Orion, are variable pitch, there is only so much pitch to play with, so the props would have to spin faster to go faster, rather than simply change pitch. If it was possible to go supersonic with propellers, they would be so noisy they would be heavily restricted, so therefore would be uneconomical.

<img src="http://www.boomspeed.com/megazone23/su27.jpg" border=0>

ALL YOUR BASE ARE BELONG TO US

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
the only time I could imagine a propeller plane going supersonic is in a complete nose down dive, with the throttles jammed open! and that will be until it slams into the ground. level flight at supersonic speeds, nah, cant imagine it.
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

the cuncks acctually had a programe were they did this, they lost alot of pilots and found out how to build air foils for supersonic air planes, thin.

<img src="http://www.wpafb.af.mil/museum/research/bombers/b5/b62-7.jpg" border=0>
overthere? naw, we'll kill 'em from here.

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
1/have "cavitation" where the airflow breaks away from the surface, and stall the propeller, (cavatation has occured on boat propellers and basically the water boils around the prop face reducing efficiency)
<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

also the NASA figured out how to work around them, the air flow was disrupted at the tips most and then worked down the propeller untill it was uneffective, they made it real thin and got 80% effectincy at .95 mach, as stated before.

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote> 2/ fly apart because of centrifugal forces acting on the propellers<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

the force isn't strong enough to put it apart, even if it was that could be over come. also it's not the centrifugal force acting one the propler it's the momentum and inertia is working on pulling it out. Centrifugal is a made up force, centripical force is real, and moceing towards the center

<img src="http://www.wpafb.af.mil/museum/research/bombers/b5/b62-7.jpg" border=0>
overthere? naw, we'll kill 'em from here.