Rutans White Knight as IR observatory

In another thread:

SSTO propulsion overview

Gordon D. Pusch wrote

[Rutan's White Knight] is basically a big high aspect-ratio
sailplane-like design with a couple of jet engines --- essentially a
civilian re-invention of the U2 spyplane. It's top speed is at most
a few hundred knots!

That makes me think: The civilian astronomers must have wanted an U2
plane with upward looking cameras, for work you can't do on the
ground, like IR and similar work.

I know that NASA has a converted KC-135 (IIRC) for that sort of thing.

When they are finished flying StarShip 1, perhaps they could design a
pod with two IR cameras for the White Knight.

Or modify it to have the cameras on board.

Is White Knight able to cut the engines, glide and then restart after
the pictures are taken ? I suppose that's how Lockheed U2 worked.

Or how much would it take to add that capability ?

Regards

Carsten Nielsen
Denmark

They already did/do use U-2's for this, NASA owns one that I knew of. Also did
some time using SR-71 blackbirds on loan, looking "up".

You don't cut the engines on the U-2 if you can help it, at the altitude you're
talking about, the difference between max speed and stall speed is a handful of
knots. Should the engine flame out, it would have to immediatley dive to keep
the airspeed inside the "coffin corner"... though on occasions when the U-2 has
flamed out, they have been known to glide across a significant amount of a
country before getting to an altitude where they have to worry about picking a
field...;-)

Anyhow, I think hyperpressure baloons are maybe a better deal for these
observations, since you get a much longer observing time, no thermal problems
from the platform itself, and no pilot with human needs and frailties.

Carsten Nielsen wrote:

In another thread:

SSTO propulsion overview

Gordon D. Pusch wrote

[Rutan's White Knight] is basically a big high aspect-ratio
sailplane-like design with a couple of jet engines --- essentially a
civilian re-invention of the U2 spyplane. It's top speed is at most
a few hundred knots!

That makes me think: The civilian astronomers must have wanted an U2
plane with upward looking cameras, for work you can't do on the
ground, like IR and similar work.

I did a bit of reading on high altitude planes. The "Perseus B" is
driven by a propeller with a triple-turbocharged piston engine.

Mike Ackerman

(Carsten Nielsen) wrote


That makes me think: The civilian astronomers must have wanted an U2
plane with upward looking cameras, for work you can't do on the
ground, like IR and similar work.


NASA has at least one ER-2, essentially a modernized U-2, that it
uses for terrestrial remote sensing and stratospheric sampling work.
Presumably it would be available for IR astronomy if needed.

I know that NASA has a converted KC-135 (IIRC) for that sort of thing.

Initially it was on a DC-8, more or less like a KC-135. (I flew on it
several times during my IR astronomy grad student days.) After the DC-8
had an unfortunate encounter with a P-3, the program moved to a C-141.
The modern version, IIRC, is being installed on a Boeing 747 SP.

It may be that the IR optics that can be carried on a U-2 sized
airplane aren't big enough to be interesting compared to other
available platforms.

(MSu1049321) wrote in message ...
They already did/do use U-2's for this, NASA owns one that I knew of. Also did
some time using SR-71 blackbirds on loan, looking "up".

You don't cut the engines on the U-2 if you can help it, at the altitude you're
talking about, the difference between max speed and stall speed is a handful of
knots. Should the engine flame out, it would have to immediatley dive to keep
the airspeed inside the "coffin corner"... though on occasions when the U-2 has
flamed out, they have been known to glide across a significant amount of a
country before getting to an altitude where they have to worry about picking a
field...;-)


So they crossed the intire Soviet Union on one tank full of fuel ?

I thought they glided a lot of time to stretch the fuel available, and
to cut the engine vibration during picture taking.

Regards

Carsten Nielsen
Denmark

So they crossed the intire Soviet Union on one tank full of fuel ?

I thought they glided a lot of time to stretch the fuel available, and
to cut the engine vibration during picture taking.

No, engines were never cut on purpose, though they did sometimes have flameouts
and compressor stalls.
The Soviet fly-overs were launched from nearby, in places like Peshawar,
Pakistan. The early missions, as you seem to suggest, didn't exactly fly
across the whole country on it's longest axis, rather, their courses were more
like loops or curved sections.

(MSu1049321) wrote in message ...
The Soviet fly-overs were launched from nearby, in places like Peshawar,
Pakistan. The early missions, as you seem to suggest, didn't exactly fly
across the whole country on it's longest axis, rather, their courses were more
like loops or curved sections.

I understood they flew out of Pakistan and landed in Bodø, Norway.

And they had fuel enough to keep the engine running all the way, of
course not at full power.

Am I right to assume that the engine was idling most of the way ? They
would have to conserve fuel in some way.

Regards

Carsten Nielsen
Denmark

(Carsten Nielsen) wrote in message . com...
I understood they flew out of Pakistan and landed in Bodø, Norway.

And they had fuel enough to keep the engine running all the way, of
course not at full power.

Am I right to assume that the engine was idling most of the way ? They
would have to conserve fuel in some way.

Where did you get this idea? It's mistaken.

The great circle range from Peshawar to Bodo is 3200 miles, which is
not extremely far. It's comparable to the New York to London
distance, and the U-2 is obviously a longer-range aircraft than most,
given its high aspect ratio and corresponding L/Dmax and its large
fuel fraction.

-jake