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

On Tue, 07 Oct 2003 06:53:12 GMT, Guy Alcala
wrote:

Given that the Streak Eagle [yadda yadda yadda]

I know it sprang from the original question, but let's face it, Streak
Eagle is just boring, boring, boring. Lots of altitude, lots of
high-level Air Force middle managers yibbling, safety margins that
actually existed, etc, etc.

Real men talk about the _authentic_ triumphs of American aviation
machismo.

Like SAGEBURNER.... Never mind the namby, limp-wristed '70's Air
Force efforts, let's get back to the heady days of the Cold War,
Marine Corps pilots with something to prove, and idiotic record
attempts being made with the new toys.

Gavin Bailey


--

Another user rings. "I need more space" he says.
"Well, why not move to Texas?", I ask. - The ******* Operator From Hell

Actually, the Streak Eagle didn't ever fly vertically for more than a
transition. The profile, as I remember (the x's are numbers I don't
remember), was to takeoff, do an Immelman at IAS x, accelerate in level
flight to Mach x, then pull to a zoom at x degrees (or maybe at an angle
attack). I never flew this profile, but was in the F-15 Test Force when
Roger Smith did. My memory is probably faulty, but I think that my
description is fairly accurate.

Could it have accelerated through Mach 1 in vertical flight? We'll never
know. It never tried to.

Jim Thomas

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. 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.

I hadn't read this post at my last reply. This description sounds
accurate for the Streak Eagle flights. I'm still not sure that the
aircraft accelerated through Mach 1 in vertical flight; it sure could
have, if it did so during an Immelman!

Jim Thomas

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]:

"The 3,000m record flight was piloted by Maj Roger Smith. With a
thrust-to-weight ratio at release of over 1.6 to 1 the 'Streak Eagle' lifted
off the ground after a roll of only 400ft, approximately seven airplane
lengths. 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."

"The third flight on 16 January was made by Maj Dave Peterson for the
15,000m record. On this and subsequent flights pilots were wearing pressure
suits. Upon liftoff Maj Peterson accelerated about 50ft over the runway to
0.65 Mach and pulled into a 55 degree flight path angle to reach the 15,000m
target altitude (49,212 ft) in 77.05 seconds. This is approximately 10sec
quicker to that altitude than the Saturn V rocket boosted the Apollo
spacecraft on its way to the moon."

"The 20,000m profile with Maj Smith again at the controls consisted of a
giant Immelmann manoeuvre starting at Mach 0.65 on the deck and pulling 2.5g
until the airplane was over the top at 32,000ft and acceperating in the
opposite direction. While passing throuhg 20,000ft the Eagle was vertical
with a 2.5g load factor and a rate of climb faster than the speed of sound.
At Mach 1.5 Smith pulled 4g into a 55 degree climb and held it there to
66,617ft in 122.94 secs elapsed time. The margin over the 'Foxbat' record
was 28%."

"Maj Peterson then took over for the 25,000m record and flew a similar
profile. Maximum speed achieved was Mach 1.8 just prior to the second
pullup. The specified altitude of 82,021ft was achieved in 161.02 sec at a
speed of Mach 0.6. The a/c eased over the top and descended without
incident. This beat the 'Foxbat's' time by 17%."

In 1973 the MiG-25 climbed to 30,000m in 4 min 3.86sec. when Maj Smith made
the flight to break this record, he lifted off the runway at a weight of
32,000lb after 500ft of ground roll, accelerating to Mach 0.65 and then
pulling into a 2.5g Immemann similar to the two previous record profiles.
After rolling 180 deg. at the top of the climb Smith accelerated in a slight
climb to build up total energy. The 'Streak Eagle' passed through Mach 2
approximately 21 miles downrange and two minutes from takeoff. At Mach 2.2
Smith pulled up to [Sic. 'at'] 4g and attained a 55 deg. flight path
whereupon the stick was relaxed to maintain a constant climb attitutde. The
30,000m mark (98,425ft) was achieved in 207.08sec, bettering the 'Foxbat'
time by 36 sec. The a/c maintained a nearly ballistic freefall path as it
went over the top at 102,400ft."

[Later in the book, describing his own flight in a stock F-15B with Lt. Col.
Dick Stamm, CO of the 22nd TFS, 36th TFW, from Alconbury, for an ACM hop
with the 527th; 36th TFW CO Col. Perry Smith was the wingman]:

"When Dick released the brakes and lit the afterburners, I was slammed back
in my seat with a force very similar to launches I had made from an aircraft
carrier catapult. Before I could catch my breath, the F-15 had traveled
900ft and rotated. The nose came up . . . and up . . . and up! From
rotation Dick pulled the nose up into a 90*degree climb a scant few hundred
feet off the runway. And the aircraft was accelerating while going straight
up*."

"I watched the earth recede rapidly -- this must be what a moon shot was
like -- and glanced up at a cloud deck at 15,000ft. We slammed through it
in a flash; no gradual ascent through. By the time I looked back it was far
below."

"Due to airspace and speed restrictions, Dick had to pull the burners back,
but there was no question a clean, lightly fueled Eagle will go supersonic
straight up from a standing start."

*Given that the F-15 seat is reclined at an angle of 13 degrees IIRC, the
a/c probably wasn't straight up as they'd be hanging by their heads if it
was, but at some angle around 77 degrees, unless Ethell was referencing the
HUD climb ladder at the time.

Guy

On Wed, 08 Oct 2003 01:51:35 GMT, Jim Thomas
wrote:

I hadn't read this post at my last reply. This description sounds
accurate for the Streak Eagle flights. I'm still not sure that the
aircraft accelerated through Mach 1 in vertical flight; it sure could
have, if it did so during an Immelman!

Jim Thomas

Guy Alcala wrote:

Ed Rasimus wrote:

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]:

"The 3,000m record flight was piloted by Maj Roger Smith. With a
thrust-to-weight ratio at release of over 1.6 to 1 the 'Streak Eagle' lifted
off the ground after a roll of only 400ft, approximately seven airplane
lengths. 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.
Guy

---remainder of detail on a great aeronautical achievement snipped--

First, let me note that I'm a political scientist by education and a
military aviator by choice. I'm not an engineer or mathematician (but
I did stay in a Holiday Inn Express last night.....)

As I recall, the first integral of velocity is acceleration. The
second integral would be rate of change of acceleration. Therefore
(without doing the math), if one were accelerating horizontally at a
high rate and then transitioned into the vertical, the addition of the
gravity vector to drag--i.e. directly in opposition to thrust, would
result in a rapid decay of the second integral--positive rate of
change of acceleration. Acceleration would slow down, although still
be increasing speed; merely at a slower rate of increase. Therefore
you might pass through the Mach while in the vertical. Note also that
the relationship between the Mach and IAS is shifting rapidly as
altitude increases. Mach 1 becomes a lower and lower IAS.

The "fastest way to Mach II" used to be the Rutowski profile. Takeoff
and accelerate to .9 mach on the deck. Hold .9 mach and transition to
climb until .9 mach intersects some airspeed (I think it was about 400
or 450 kts, but am not sure--it was a long time ago.) Then hump over
to allow the aircraft to accelerate to 1.2 M. This usually took place
at around FL 210 and resulted in a slight descent to about FL 180. At
1.2 M, establish that IAS and maintain the climb on IAS until reaching
Mach 2--usually around FL 450. The amazing thing was the sensation of
"the faster you go, the faster you go faster!" The acceleration on
takeoff from about 400 kts IAS until reaching .9 near 600 kts was a
kick!

My point remains. If you established vertical at a given subsonic IAS,
then selected reheat, I continue to doubt that the aircraft could
accelerate through the mach. It's an entirely different dynamic
situation than the Streak Eagle profile.

"Ed Rasimus" wrote in message
...
On Wed, 08 Oct 2003 01:51:35 GMT, Jim Thomas
wrote:

I hadn't read this post at my last reply. This description sounds
accurate for the Streak Eagle flights. I'm still not sure that the
aircraft accelerated through Mach 1 in vertical flight; it sure could
have, if it did so during an Immelman!

Jim Thomas

Guy Alcala wrote:

Ed Rasimus wrote:

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]:

"The 3,000m record flight was piloted by Maj Roger Smith. With a
thrust-to-weight ratio at release of over 1.6 to 1 the 'Streak Eagle'
lifted
off the ground after a roll of only 400ft, approximately seven airplane
lengths. 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.
Guy

---remainder of detail on a great aeronautical achievement snipped--

First, let me note that I'm a political scientist by education and a
military aviator by choice. I'm not an engineer or mathematician (but
I did stay in a Holiday Inn Express last night.....)

As I recall, the first integral of velocity is acceleration.

Nope.

P-42 (record-breaking SU-27) could accelerate through vertical, 90 degrees
flight.

Nele

NULLA ROSA SINE SPINA

Jim Thomas wrote in message ...
I hadn't read this post at my last reply. This description sounds
accurate for the Streak Eagle flights. I'm still not sure that the
aircraft accelerated through Mach 1 in vertical flight; it sure could
have, if it did so during an Immelman!

Jim Thomas

On Wed, 8 Oct 2003 08:00:01 -0700, "Tarver Engineering"
wrote:

"Ed Rasimus" wrote in message
As I recall, the first integral of velocity is acceleration.

Nope.


Ahh, now I see. Thanks for that typically helpful addition to the
thread. Enlightenment can come in such small and pithy comments.

[Later in the book, describing his own flight in a stock F-15B with Lt. Col.
Dick Stamm, CO of the 22nd TFS, 36th TFW, from Alconbury, for an ACM hop
with the 527th; 36th TFW CO Col. Perry Smith was the wingman]:

"When Dick released the brakes and lit the afterburners, I was slammed back
in my seat with a force very similar to launches I had made from an aircraft
carrier catapult. Before I could catch my breath, the F-15 had traveled
900ft and rotated. The nose came up . . . and up . . . and up! From
rotation Dick pulled the nose up into a 90*degree climb a scant few hundred
feet off the runway. And the aircraft was accelerating while going straight
up*."

"I watched the earth recede rapidly -- this must be what a moon shot was
like -- and glanced up at a cloud deck at 15,000ft. We slammed through it
in a flash; no gradual ascent through. By the time I looked back it was far
below."

"Due to airspace and speed restrictions, Dick had to pull the burners back,
but there was no question a clean, lightly fueled Eagle will go supersonic
straight up from a standing start."

I watched F-15s do this at St Louis airport back in the 80's.
What did they call it? A "Trojan takeoff"?

The Macair guy claimed they used this profile because it kept the aircraft
noise over the airport and didn't disturb the neighbors as much.
He kept a straight face while he said it, too.
I admired him for that.

--
Harry Andreas
Engineering raconteur

"Ed Rasimus" wrote in message
...
On Wed, 8 Oct 2003 08:00:01 -0700, "Tarver Engineering"
wrote:

"Ed Rasimus" wrote in message
As I recall, the first integral of velocity is acceleration.

Nope.


Ahh, now I see. Thanks for that typically helpful addition to the
thread. Enlightenment can come in such small and pithy comments.

Integral A dt = V0 + At =V