Well, if you could get the engine to keep running & the wings producing lift that high. OTOH, I wonder if you had something heavy, like a P-47 &/or sleek, like a late Spit or maybe even a Sea Fury, & fit it with a full feathering prop like twin engined a/c use & at the speed where the prop is maxed out, feather the prop & maybe get over the hump.
According to my trusty US Standard Atmosphere tables, the speed of sound is the same from 36089 feet on up: 968.1 feet/sec, or 660 miles/hr. So according to that, our man Kittenger didn't quite make supersonic (only made .93 Mach).
Steve H
J>
Hi Bill, I'm a 1/48 case myself. So I'll sacrifice my Heller kit. Any chance of getting a copy of your copy my way? Pretty please
-- Dennis Loep The Glueing Dutchman
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny ...'" Isaac Asimov
Yes - it's a function of temperature; so from the tropopause up it's a "constant" for talking purposes.
This article claims he reached 614 - 714 mph, but doesn't say at what altitude:
Like I said before - the higher you go, the faster you fall...
Possibly but it was probably done for safety's sake. Flying that fast in the East would worry a lot of folks.
Bill Banaszak, MFE
Actually, for a piston engined airplane that makes things harder, not easier...from a horsepower available point of view.
Thin air is bad air - from both dynamic pressure and "breathability" points of view. Less dynamic pressure, less lift - so yes you have to fly faster...but there is also less dense air for the engine to breathe, so there is less power available to make that speed (most engines make max power at sea level conditions). You have to find a balance point - where both are maximized. The Conquest Team may have chosen their location for just that reason.
With the supercharger fitted to Conquest 1's R-2800 (or R-3350?), I don't think that altitude affected power output. In fact, many of the larger, later radials could put out more HP at altitude than at sea level due to the blower setup. I'm sure there are large areas nearer sea level available so safety wouldn't be an issue.
Much of the publicity at the time touted him with breaking the soundbarrier, and many articles today parrot this assertation. However, Mr. Kittenger himself admits that there was no way he could have done that, explaining the scientific limitations etc. As a native New Mexican, I take great pride in this achievment too, as this was at White Sands.... as if I had anything to with it.
rch
That doesn't really make sense...they may have been wastegated to do so, but the air is denser at sea level and so they should make maximum hp there. I know you can over-boost the manifold and blow the engine up if you're not careful with the throttle at lower altitudes...espesially in a setup with a fixed wastegate.
What a turbo or super chager is meant to do (for an aircraft) is insure max hp is available up to the aircraft's service ceiling if possible - or at least throughout as much of the envelope as possible, independent of altitude. There should still be a point where the power available (or "transmittable" as a function of propeller efficiency) and the speed/drag polars for a given design cross or may be optimal in trade.
And you can always just fly over the water, if you're really worried about dropping the aiplane on someone - Thompson Trophy races spring to mind.
I have to be a bit skeptical in the Col's assertion that there was "no way" he might have achieved Mach...I've heard assertions that some Mk-80 series bombs break Mach in freefall from as low as 25-30K. Though I can't seem to find anyone that can tell me what the terminal velocity of a Mk-80 series body is...
Given Kittenger's initial conditions and the lower sonic velocity at that altitude one would have to postulate that it could have been possible. Being a jumper myself, I can attest that there would have been no way he would have "felt" the speed once the pressure wave built in front of him...though he should have felt some heat buildup, maybe.
Someone should do a CFD study based on his drag polar and see if the math allows it.
Sounds like a job for those myth busters on one of the cable channels.
WmB
To reply, get the HECK out of there snipped-for-privacy@earthlink.net
I want to thank you for your answers on this topic. It convinces we that only way a P-47 could break the sound barrier was if it lost both wings, its propeller and only then might it just nudge the envelope a few milliseconds prior to impact. I figure though, that in the heat of battle, pilots from both sides, probably thought they entered the sound barrier several years before Chuck Yeager did. Thanks Again :-) Mike IPMS
Sure, IF..... you can get a prop A/C up to the same altitude he was. Dont think it could ever happen...............
BTW, there were claims that the Me 163 actually went supersonic as well. Much more likely than any prop A/C ever doing it !
"Only a Gentleman can insult me, and a true Gentleman never will..."
It would be very hard to know for sure how fast any plane actually was flying at except during special flight tests with sophisticated instrumentation.
I think when we say the airplane is going at a certain speed, we mean with respect to air at rest, far from aircraft surface. Air around an aircraft is disturbed by an airplane's passage, speeding up or slowing down.
Shock wave first appears on top surface of wing, as that is usually fastest LOCAL airflow. Unfortunately, on any operational airplane, airspeed indicator reads local airflow. Only by radar tracking or use of special boom-mounted pitot tubes can one measure airspeed with respect to actual ambient (undisturbed) air.
Shock waves may occur at speeds WELL below sonic when talking about actual airspeed. It is the speeded up local flow that starts these shock waves. Depending on thickness of airfoil, this can start at speeds of about 400 mph.
No problem getting to altitude - you sling it under a carrier aircraft like an X-15/B-52 combination...or you use a JATO assist...or you climb slowly - not trying to break a time to climb record, just a speed record. I still hold firm that it could be done, though it would most certainly not be practical...how 'bout it, Mr. Rutan?..
I've heard/read in a few places that the Me 163 was/is a planform which is "aerodynamically capable" of exceeding Mach 1, but I've also read that it is NOT structurally capable of doing so as built/fielded.
Well stated, Don...
Even more important than structure is control. Big problem that X-1 was really set up to do was investigate center of pressure and moment changes on wing at transsonic speeds. And, controllability of elevator controls. If plane goes unstable at transsonic speeds (or at ANY speed) one does not have a very nice flight :-) Movement of shock waves on wing, stab, and elevator had drastic effect of creating large and undesirable pitch up or pitch down forces.
Pe>
That would be another fun/interesting CFD study, or perhaps someone could "flight test" the 163 in a sim like X-Planes and let us know what happens out there at 1.x M...
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