Why does the shuttle throttle on ascent?

MichaelJP wrote:
Thanks Pat - the ME-163 is modelled in the superb combat flight sim IL-2,
trying it last night they must have modelled this aircraft quite nicely
as I found it very difficult to bleed off enough speed in the hold-off,
exactly as you said above. Landing on the grass the skid dug in and
certainly a real aircraft would have been destroyed.

Obviously somebody did their research when writing the program for it.
It might have something to do with the fact tat the ailerons also serve as
its elevators.
Does the simulator have the spoilers on it?
The controls for them are located just to the left of the control stick.
There's a manual pump mechanism handle with a ball top, and to the rear of
it the actual flap control lever.
On the actual aircraft you turn the control handle 180 degrees, then pump
the pump handle six times to put the flaps fully down.

Don't think so, but it does have landing flaps. IL-2 is pretty good as a
simulator but it models 100's of different aircraft and variants so it has
to make compromises and not all the subtleties are there. Amazing value
though for the price.

Difference is I could reset for another go

Doing some other testing I found it impossible to recover from a spin
entered from a slow-speed stall. Wonder if that's correct?

It's supposed to have a very abrupt and severe stall according to Eric
Brown's flight notes; he states it goes into a steep spiraling dive, but
you can recover from it in a "straightforward" manner. I don't know it
that means you turn into the spin and convert it into a dive or what.
BTW, he was able to get the one he was flying up to 440 mph in _gliding_
flight in a dive, which gives you some idea of just how aerodynamic this
little thing was.
He wrecked his Komet by doing progressively faster and faster ballasted
landings as tests for a British high speed research aircraft that the RAF
was planning, till the skid finally came through the floorboard of the
cockpit after a landing at 158 mph.

Pat

Interesting, what's your source for the Eric Brown story, I'd like to read
more.

MichaelJP wrote:

Interesting, what's your source for the Eric Brown story, I'd like to read
more.


Eric Brown wrote a series books about the 487 types of planes he flew
in his career as a test pilot.
The one I have is "Wings of The Luftwaffe"(all the titles have "Wings"
in them).
Each aircraft type has both a cutaway of the whole aircraft, and a
detailed drawing of the cockpit from the pilot's perspective with
everything labeled.
He gives an overview of all the handling characteristics of each type:
http://www.amazon.com/Wings-Luftwaff.../dp/0385135211
In another book, "Wings of the Weird and Wonderful" he actually flew one
of these: http://www.warbirdsresourcegroup.org/LRG/bv141.html

Pat

wrote in message
oups.com...
The shuttle actually throttles back twice during ascent. The first time
is at max Q. This is not a 3 G situation for the vehicle. After the
solids are dropped, the shuttle again throttles back in the last 30
seconds or so before main engine cut-off, so as to not exceed 3 G's of
forward acceleration when the fuel is almost gone. Whether this is due
to a structural or other reason, I'm not sure. But structural makes the
most sense for several reasons, weight being the primary one.

Bud

The answer is:
So Navy fighter pilots can fly the shuttle :-)

Danny Deger

snip

Danny Deger wrote:
wrote in message
oups.com...
The shuttle actually throttles back twice during ascent. The first time
is at max Q. This is not a 3 G situation for the vehicle. After the
solids are dropped, the shuttle again throttles back in the last 30
seconds or so before main engine cut-off, so as to not exceed 3 G's of
forward acceleration when the fuel is almost gone. Whether this is due
to a structural or other reason, I'm not sure. But structural makes the
most sense for several reasons, weight being the primary one.

Bud

The answer is:
So Navy fighter pilots can fly the shuttle :-)

Danny Deger

snip

I read that. Nice double meaning. However I think Navy pilots get to 9
G's like AF Raptor pilots do. I was just explaining to the ones that
thought the max Q issue was 3 G's, which it is not.

Bud


Danny Deger wrote:
wrote in message
oups.com...
The shuttle actually throttles back twice during ascent. The first time
is at max Q. This is not a 3 G situation for the vehicle. After the
solids are dropped, the shuttle again throttles back in the last 30
seconds or so before main engine cut-off, so as to not exceed 3 G's of
forward acceleration when the fuel is almost gone. Whether this is due
to a structural or other reason, I'm not sure. But structural makes the
most sense for several reasons, weight being the primary one.

Bud

The answer is:
So Navy fighter pilots can fly the shuttle :-)

Danny Deger

snip

wrote in message
ups.com...
I read that. Nice double meaning. However I think Navy pilots get to 9
G's like AF Raptor pilots do. I was just explaining to the ones that
thought the max Q issue was 3 G's, which it is not.


This is true. Two different times to throttle on ascent for 2 different
reasons.

Danny Deger

"Pat Flannery" wrote in message
...


Henry Spencer wrote:

Of course, the crew that *really* didn't want to hear/see anything like
that were the folks aboard the Ethan Allen in May 1962, when she did the
only US SLBM test ever with a live warhead...

Frigate Bird! Hardly anyone knows we ever did that one:
http://www.navy.mil/navydata/cno/n87...igate_bird.htm
Where I'd have been a little queasy about being is on the Carbonero or
Medregal at twenty-five miles from the aim point, and thinking to yourself
"I sure hope that thing's guidance system works right." :-)

I only read about it since someone asked if we had ever done that and I
figured I'd look it up.



Pat

Danny Deger wrote:

While in the atmosphere the main engines are throttled back to reduce the
maximum aerodynamic pressure. The grain in the SRB is also designed to
have them go through a period of reduced thrust at about the same time.

Not sure what you mean by "grain in the SRB", but the physical propellant
shape is designed the reduce the thrust by approximately a third 50 seconds
after lift-off to prevent overstressing the vehicle during maximum dynamic
pressure.

Hilton

Pat Flannery wrote:



MichaelJP wrote:
I wonder how many found it too much and came to grief - were there any
trainer versions of the P51D or was the first flight always the first
solo as well?


I don't think I've ever seen a trainer P-51, in fact most U.S. WW II
fighter didn't have a trainer version.
I assume that after you had done enough hours in a Texan trainer they
assumed you were ready to take on a Mustang, although I have heard of
some pilots training stateside in P-39s before moving up to P-47s or
P-51s overseas.
(Chuck Yeager for instance)

During the war there weren't any 2 chair P-51s (Except a few one-offs like
the 2-seat P-51B that was used by Eisenhower for direct recon of Normandy.)

There were some TF-51Ds put together after the war by Temco - They can be
spotted by their having the bigger F-51H fin & rudder, and a canopy shape
that gives a bit more rear headroom. Cavalier made some, as well -
including a couple delivered to the U.S. Army in the 1960s for use as chase
planes for the AH-56 Cheyenne Compound Helicopter.

But, backduring the War, the usual procedure before transitioning to a singe
seat fighter was to demonstrate proficiency in landing an AT-6 from the
read seat.
This gave the same lousy over-the-nose visibility, and the T-6's much
snarkier behavior on landing and rollout meant that if you could handle
that, you could pretty much handle anything.

Figher training (More of less what we'd call LIFT (Lead-In Fighter Training
these days) was typically performed in war-weary P-39s or P-40s. It was
considered part of the Advanced Single Engine syllabus.

The U.S. Aviation Training Programs, both Army and Navy, were some of the
most amazing miracles of WW 2. A lot of study went into syllabus and
methods - And the result was Pilots coming out of training in with 250-300
hours who could not only fly a fighter, but fly it on instruments, navigate
their way from England to Prague and back, and fight the Luftwaffe (or the
IJN) to a standstill when they got there.
Well, and the U.S. Aviation Industry, that could build fighters that could
not only fly from England to Prague, but take on the short-ranged
interceptors when it got there, and, if necessary, run them out of gas, and
fly home.
(The only German fighter pilots who got instrument training were the
NachtJagd. This was a factor in choosing bomber pilots to fly the early
jets - they could make instrument let-down in the usual crappy German
weather. An Me 262 didn't have the fuel on board to stooge around looking
for a hole in the clouds to descend through, or a VFR airfield.

Pete Stickney
Without data, all you have is an opinion

Peter Stickney wrote:
(The only German fighter pilots who got instrument training were the
NachtJagd.


How would you like to be the pilot of one of those single seat radar
equipped FW-190 night fighters?
That must have kept one mighty busy.
See if you can figure this out BTW; it's a Ba-349 "Natter" control
panel:
http://www.fantasyofflight.com/Image...er_Cockpit.jpg
That thing in the middle with the crosshairs on it has to have something
to do with the semi-automated way it was vectored by ground control to
the incoming bombers... but how does it work? I don't think the nose was
recoverable after being jettisoned, so it has to be cheap, but it looks
pretty sophisticated, like something that might have a gyro or cathode
ray tube in it.

Pat