WaltBJ wrote:

SNIP:
Ed Rasimus wrote:
Now, let's put to bed this idea of accelerating through the mach
straight up.
A couple reminders:
1) with a thrust to weight atio of 1.6:1 the Streak Eagle is
distinctly higher powered than anything any of us flew in the service.
2) It's shedding weight in full afterburner during the takeoff and
climb. I don't know what the fuel consumption of an F15 full-out is
but it's certainly over a ton a minute, so the T/W is increasing.

F100-PW-100, 860lb./min. SL static uninstalled, each (probably not with the
VMAX switch). As you say, could be more when they're cooking along.

snip

5) BTW with Jeff Ethell's flying experience and the highly visible
attitude direction indicator in an F15 why question his statement that
they were indeed vertical? Checking a vertical climb on the gyro is no
big deal - and one also looks out at the horizon.

I'm allowing for the possibility that he was a bit overwhelmed by the rate
of data. ISTM that Ethell mainly flew prop a/c; AFAIK he was never a jet
jock by trade. I've got an account from a seasoned RCAF jet jock (Mustang
and Vampire in training, Sabre in Germany) transitioning to the CF-104D,
who says he was way behind the a/c on his first takeoff, which was his
first a/c with A/B.

It seems possible to me that Ethell may have been in the same boat, as
although he'd undoubtedly flown in jet fighters prior to that, he'd never
flown them for a living. Besides, I imagine the seat of the pants
difference between true vertical and 75 degrees or so is pretty small, if
you're not rolling on the way up. But maybe he was staring right at the
HUD ladder the entire time, and they were in fact climbing at 90 deg. I
don't know, I just thought I'd better mention the possibility that they
weren't true vertical.

Guy