Me-262, NOT Bell X-1 Broke SB First

Ed Rasimus wrote:

On Mon, 06 Oct 2003 19:03:36 GMT, Guy Alcala
wrote:

Ed Rasimus wrote:

snip

Now, let's put to bed this idea of accelerating through the mach
straight up. While modern jets with greater than 1-to-1 T/W ratios can
accelerate through the vertical, I sincerely doubt the mach claim. Too
much is going on with drag curves, deteriorating performance with
altitude, losses in engine efficiency, etc. I think only heavy lift
rockets accelerate through the mach in near vertical, but they
transition out of vertical fairly early in the flight trajectory and
may not be vertical either.

Oh, I don't know. While not a stock production a/c, the Streak Eagle was
certainly capable of doing so [From Jeff Ethell's book on the F-15]:

--rest of very detailed and impressive data snipped, but should be
referred to for context.---

Guy

All well and good, but the issue is could an airplane accelerate
through the mach vertically. I contend the answer is no. While the
Streak Eagle stuff is arguably the best documented and most
impressive, it involves accelerating transition into the vertical.

To
truly be an acceleration through the mach vertically, it would require
establishing the vertical, then choosing max power and performing the
acceleration.

Seems to me that's just what happened in these cases:

"Smith quickly raised the landing gear and maintained nearly level
flight while accelerating to approximately Mach 0.6. The aircraft was then
rotated by a 5g pullup to a near vertical climb attitude. The Eagle
accelerated during this climb to Mach 1 and reached the specified 3,000m
altitude in 27.57 seconds. The 6,000m, 9,000m, and 12,000m records, were
set by Maj Willard 'Mac' MacFarlane in one flight of 16 January [1975]. The
profile was similar to the 3,000m flight except that a maximum speed of Mach
0.7 was obtained before the pullup. MacFarlane and his Eagle were at sonic
speed only 23 seconds after brake release."

Now, an aircraft that can pull 5g to (near) vertical and then accelerate to
Mach 1 or better, and do so in 23 seconds from start of takeoff roll,
certainly has more than enough Ps without all that G.


IOW, pick a subsonic speed, such as 600 KIAS for the
pullup to vertical, and even allow for throttle modulation to maintain
constant airspeed through the transition to stabilized vertical at 600
KIAS, NOW accelerate from that point through the mach.

I'm still a skeptic.

Given that the Streak Eagle went through the mach while vertical at 20,000
feet while pulling 2.5g in an Immelmann that started on the deck at M0.65, I'm
not. You were the one talking about drag curves being a factor; the induced
drag from pulling 2.5 to 5g inot or through the vertical is certainly
significant, and yet the a/c was still accelerating the whole time.

Guy