Fighter Jocks and Old School Aviation Buffs give me a hand...
 

I have read in a couple of different places that the F-104 Starfighters best glide with T/O flaps up is 275kts... And they went on to say that above FL500, this is supersonic..

Ok is that true? I am having a bit of trouble buying it.

According to my calculation the speed of sound at FL500 would be

Speed of sound 761 mph X Speed of Sound Ratio at 50K on a standard day.. So 761 X 0.8671 = 659.86 mph

659.86 mph/1.15 = 573 knots...

K... thats not 275 knots... Am I missing something? Whats the deal? Anybody got any sources?

Think IAS <g>, IAS is low at high altitudes but the TAS is highhhhhh.

Speed of sound has nothing to do with altitude. Only temperature changes it. Of course, as you go up it gets colder. If I had an E6B around I would calculate what it would be, but I don't. FL500 would be tough, that's usually above the tropopause I think, so I don't know what ISA would be.

Yes, it is over Mach 1 at that altitude. Virtual E6B:http://www.luizmonteiro.com/Altimetry.htm

The human body in free fall can exceed Mach 1 from very high altitudes as was proven in balloon jumps from 100,000 feet. Joe Kittinger:http://www.youtube.com/watch?v=5BOK1aMIhp4

Lousiest glide ratio ever?
 

MGen Bob Rushworth used to tell about the time he had an uncommanded landing gear extension in the X-15 at Mach 3. The airplane had heated up and stretched, but the gear unlock cable did not stretch, so it was pulled. His glide was a lot shorter than planned, with a hideous rate of descent, but he made a successful landing on an alternate lakebed. :eek:

You need to convert TAS to IAS. I also think that the speed of sound at 50k is less than 573 true, but I'm just going on feel here. Don't ask me to do the math.

I was at 50K last night and over the Mach at 300 KCAS. In MIL power. And accelerating. Bragging....

I'll let the U-2 guys state their's but if I remember correctly (40 years ago) , at 70,000 in the RB-57F our IAS was about 115 Kts.