orbiter maneuvering

How much maneuvering can orbiter do while descending through upper atmosphere?
Is it possible to modify descent profile by changing vehicle's attitude
slightly, like pitching up or down a bit, or forward-slipping a little?
Can thermal load distribution be modified that way? In other words, how much
control does the crew have between de-orbiting burn and final approach?


Andrey

"Andrey Serbinenko" wrote in message
...

How much maneuvering can orbiter do while descending through upper
atmosphere?
Is it possible to modify descent profile by changing vehicle's attitude
slightly, like pitching up or down a bit, or forward-slipping a little?
Can thermal load distribution be modified that way? In other words, how
much
control does the crew have between de-orbiting burn and final approach?


Andrey


Obviously, they have enough control to be able to switch runways at the
landing location. On this last mission, they switched from runway 33 to 15
somewhere in the middle of the descent, after the de-orbit burn.

JD

That's during the approach -- this I understand. My question was more about
maneuvering while still going at a very high speed.

Andrey


Joe Delphi wrote:
"Andrey Serbinenko" wrote in message
...

How much maneuvering can orbiter do while descending through upper
atmosphere?
Is it possible to modify descent profile by changing vehicle's attitude
slightly, like pitching up or down a bit, or forward-slipping a little?
Can thermal load distribution be modified that way? In other words, how
much
control does the crew have between de-orbiting burn and final approach?


Andrey


Obviously, they have enough control to be able to switch runways at the
landing location. On this last mission, they switched from runway 33 to 15
somewhere in the middle of the descent, after the de-orbit burn.

JD

Andrey Serbinenko wrote:
That's during the approach -- this I understand. My question was more about
maneuvering while still going at a very high speed.


Actually, the Orbiter has quite a bit more manuvering capability during
descent than you might think.

When the STS was originally being designed, NASA was cooperating with
the Air Force so that the shuttle could be used for both civillian and
millitary purposes (this was primarily for budgetary reasons...NASA
knew that cooperating with the Air Force meant that the shuttle project
wouldn't be sacked by Congress). One of the Air Force requirements was
for the shuttle be able to launch into a polar orbit from Vandenberg
AFB in California, and then land one orbit later after dropping off a
payload in space. The problem with this is that the Earth rotates
beneath the orbit of a space shuttle while in space, so the runway at
Vandenberg would have moved about 900 miles east of the orbital track
by the time the orbiter comes around to land.

Long story short: the Orbiters were given larger, delta wings, which
provided a cross-range capability of about 1085 miles on descent.
Basically what happens is that the shuttle goes through a series of
"roll-reversals" during descent to bleed off the energy that was built
up during ascent. By adjusting the timing and magnitude of these
maneuvers, the lift generated by the wings allow the orbiter to maunver
left or right of its orbital track. Obviously, the farther into
descent the orbiter is, the less crossrange capability it has, so most
crossrange manuvers are planned before the deorbit burn to allow the
GPCs to manage the Orbiter's energy profile accordingly. During the
last flight, the change from runway 33 to runway 15 only required the
orbiter to reach a target about three miles away from the original
target, so as you saw, it was possible to swap runway direction fairly
late in the descent.

Even though the polar orbit flights were ultimately canceled, the
additional crossrange capability has come in handy on a number of
occassions, providing additional landing opportunities than would have
been possible with a less manuverable design.

"Craig Cocca" wrote:

Even though the polar orbit flights were ultimately canceled, the
additional crossrange capability has come in handy on a number of
occassions, providing additional landing opportunities than would have
been possible with a less manuverable design.

Jorge has bandied about the theory that the large crossrange would
have evolved *anyhow*, as low crossrange orbiters lack abort (TAL) and
landing opportunities. This makes them much more difficult to operate
and lowers programmatic safety.

D.
--
Touch-twice life. Eat. Drink. Laugh.

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

On Wed, 19 Jul 2006 13:09:05 -0700, Craig Cocca wrote:

Andrey Serbinenko wrote:
That's during the approach -- this I understand. My question was more about
maneuvering while still going at a very high speed.


Actually, the Orbiter has quite a bit more manuvering capability during
descent than you might think.

When the STS was originally being designed, NASA was cooperating with
the Air Force so that the shuttle could be used for both civillian and
millitary purposes (this was primarily for budgetary reasons...NASA
knew that cooperating with the Air Force meant that the shuttle project
wouldn't be sacked by Congress). One of the Air Force requirements was
for the shuttle be able to launch into a polar orbit from Vandenberg
AFB in California, and then land one orbit later after dropping off a
payload in space. The problem with this is that the Earth rotates
beneath the orbit of a space shuttle while in space, so the runway at
Vandenberg would have moved about 900 miles east of the orbital track
by the time the orbiter comes around to land.

Long story short: the Orbiters were given larger, delta wings, which
provided a cross-range capability of about 1085 miles on descent.
Basically what happens is that the shuttle goes through a series of
"roll-reversals" during descent to bleed off the energy that was built
up during ascent. By adjusting the timing and magnitude of these
maneuvers, the lift generated by the wings allow the orbiter to maunver
left or right of its orbital track. Obviously, the farther into
descent the orbiter is, the less crossrange capability it has, so most
crossrange manuvers are planned before the deorbit burn to allow the
GPCs to manage the Orbiter's energy profile accordingly. During the
last flight, the change from runway 33 to runway 15 only required the
orbiter to reach a target about three miles away from the original
target, so as you saw, it was possible to swap runway direction fairly
late in the descent.

http://www.nasa.gov/mission_pages/sh...s/landing.html

Here you can see STS-121 entry ground tracks that are one orbit apart.
Both were planned for a downwind landing on runway 33. It doesn't show the
runway 15 hack, but it has essentially the same approach except it crosses
the runway a little bit north of this track (essentially the same distance
from the end of the runway), and circles to the north.

http://www.nasa.gov/images/content/1...202_close2.gif

--
Craig Fink
Courtesy E-Mail Welcome @

(Derek Lyons) wrote in news:44bf9c3d.110331312
@news.supernews.com:

"Craig Cocca" wrote:

Even though the polar orbit flights were ultimately canceled, the
additional crossrange capability has come in handy on a number of
occassions, providing additional landing opportunities than would have
been possible with a less manuverable design.

Jorge has bandied about the theory that the large crossrange would
have evolved *anyhow*, as low crossrange orbiters lack abort (TAL) and
landing opportunities. This makes them much more difficult to operate
and lowers programmatic safety.

To be fair, while I've bandied the theory, I can't claim it as my own. I
heard it from Robert Thompson at a speech he gave to the ASE some years
ago.


--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

"Craig Fink" wrote in message
news
On Wed, 19 Jul 2006 13:09:05 -0700, Craig Cocca wrote:

Andrey Serbinenko wrote:
That's during the approach -- this I understand. My question was more
about
maneuvering while still going at a very high speed.


Actually, the Orbiter has quite a bit more manuvering capability during
descent than you might think.

When the STS was originally being designed, NASA was cooperating with
the Air Force so that the shuttle could be used for both civillian and
millitary purposes (this was primarily for budgetary reasons...NASA
knew that cooperating with the Air Force meant that the shuttle project
wouldn't be sacked by Congress). One of the Air Force requirements was
for the shuttle be able to launch into a polar orbit from Vandenberg
AFB in California, and then land one orbit later after dropping off a
payload in space. The problem with this is that the Earth rotates
beneath the orbit of a space shuttle while in space, so the runway at
Vandenberg would have moved about 900 miles east of the orbital track
by the time the orbiter comes around to land.

Long story short: the Orbiters were given larger, delta wings, which
provided a cross-range capability of about 1085 miles on descent.
Basically what happens is that the shuttle goes through a series of
"roll-reversals" during descent to bleed off the energy that was built
up during ascent. By adjusting the timing and magnitude of these
maneuvers, the lift generated by the wings allow the orbiter to maunver
left or right of its orbital track. Obviously, the farther into
descent the orbiter is, the less crossrange capability it has, so most
crossrange manuvers are planned before the deorbit burn to allow the
GPCs to manage the Orbiter's energy profile accordingly. During the
last flight, the change from runway 33 to runway 15 only required the
orbiter to reach a target about three miles away from the original
target, so as you saw, it was possible to swap runway direction fairly
late in the descent.

http://www.nasa.gov/mission_pages/sh...s/landing.html

Here you can see STS-121 entry ground tracks that are one orbit apart.
Both were planned for a downwind landing on runway 33. It doesn't show the
runway 15 hack, but it has essentially the same approach except it crosses
the runway a little bit north of this track (essentially the same distance
from the end of the runway), and circles to the north.

http://www.nasa.gov/images/content/1...202_close2.gif

I'm certainly going to miss this stuff come 2010 when the shuttle retires
and we're back to boring capsules and splashdowns...

MichaelJP wrote:
"Craig Fink" wrote in message
news
On Wed, 19 Jul 2006 13:09:05 -0700, Craig Cocca wrote:

Andrey Serbinenko wrote:
That's during the approach -- this I understand. My question was more
about
maneuvering while still going at a very high speed.


Actually, the Orbiter has quite a bit more manuvering capability during
descent than you might think.

When the STS was originally being designed, NASA was cooperating with
the Air Force so that the shuttle could be used for both civillian and
millitary purposes (this was primarily for budgetary reasons...NASA
knew that cooperating with the Air Force meant that the shuttle project
wouldn't be sacked by Congress). One of the Air Force requirements was
for the shuttle be able to launch into a polar orbit from Vandenberg
AFB in California, and then land one orbit later after dropping off a
payload in space. The problem with this is that the Earth rotates
beneath the orbit of a space shuttle while in space, so the runway at
Vandenberg would have moved about 900 miles east of the orbital track
by the time the orbiter comes around to land.

Long story short: the Orbiters were given larger, delta wings, which
provided a cross-range capability of about 1085 miles on descent.
Basically what happens is that the shuttle goes through a series of
"roll-reversals" during descent to bleed off the energy that was built
up during ascent. By adjusting the timing and magnitude of these
maneuvers, the lift generated by the wings allow the orbiter to maunver
left or right of its orbital track. Obviously, the farther into
descent the orbiter is, the less crossrange capability it has, so most
crossrange manuvers are planned before the deorbit burn to allow the
GPCs to manage the Orbiter's energy profile accordingly. During the
last flight, the change from runway 33 to runway 15 only required the
orbiter to reach a target about three miles away from the original
target, so as you saw, it was possible to swap runway direction fairly
late in the descent.

http://www.nasa.gov/mission_pages/sh...s/landing.html

Here you can see STS-121 entry ground tracks that are one orbit apart.
Both were planned for a downwind landing on runway 33. It doesn't show the
runway 15 hack, but it has essentially the same approach except it crosses
the runway a little bit north of this track (essentially the same distance
from the end of the runway), and circles to the north.

http://www.nasa.gov/images/content/1...202_close2.gif

I'm certainly going to miss this stuff come 2010 when the shuttle retires
and we're back to boring capsules and splashdowns...

Michael,

As I understand it, the only splashdowns will be during contingency
landings. Routine CRV landings are planned to occur on dry land. I
think people are still considering the details of how to soften final
touchdown impact (bags vs rockets vs large fields of Jet-Puff
marshmallows) after the parachute descent.

Blue skies

John

"John" wrote in message
oups.com...

MichaelJP wrote:
"Craig Fink" wrote in message
news
On Wed, 19 Jul 2006 13:09:05 -0700, Craig Cocca wrote:

Andrey Serbinenko wrote:
That's during the approach -- this I understand. My question was more
about
maneuvering while still going at a very high speed.


Actually, the Orbiter has quite a bit more manuvering capability
during
descent than you might think.

When the STS was originally being designed, NASA was cooperating with
the Air Force so that the shuttle could be used for both civillian and
millitary purposes (this was primarily for budgetary reasons...NASA
knew that cooperating with the Air Force meant that the shuttle
project
wouldn't be sacked by Congress). One of the Air Force requirements
was
for the shuttle be able to launch into a polar orbit from Vandenberg
AFB in California, and then land one orbit later after dropping off a
payload in space. The problem with this is that the Earth rotates
beneath the orbit of a space shuttle while in space, so the runway at
Vandenberg would have moved about 900 miles east of the orbital track
by the time the orbiter comes around to land.

Long story short: the Orbiters were given larger, delta wings, which
provided a cross-range capability of about 1085 miles on descent.
Basically what happens is that the shuttle goes through a series of
"roll-reversals" during descent to bleed off the energy that was built
up during ascent. By adjusting the timing and magnitude of these
maneuvers, the lift generated by the wings allow the orbiter to
maunver
left or right of its orbital track. Obviously, the farther into
descent the orbiter is, the less crossrange capability it has, so most
crossrange manuvers are planned before the deorbit burn to allow the
GPCs to manage the Orbiter's energy profile accordingly. During the
last flight, the change from runway 33 to runway 15 only required the
orbiter to reach a target about three miles away from the original
target, so as you saw, it was possible to swap runway direction fairly
late in the descent.

http://www.nasa.gov/mission_pages/sh...s/landing.html

Here you can see STS-121 entry ground tracks that are one orbit apart.
Both were planned for a downwind landing on runway 33. It doesn't show
the
runway 15 hack, but it has essentially the same approach except it
crosses
the runway a little bit north of this track (essentially the same
distance
from the end of the runway), and circles to the north.

http://www.nasa.gov/images/content/1...202_close2.gif

I'm certainly going to miss this stuff come 2010 when the shuttle retires
and we're back to boring capsules and splashdowns...

Michael,

As I understand it, the only splashdowns will be during contingency
landings. Routine CRV landings are planned to occur on dry land. I
think people are still considering the details of how to soften final
touchdown impact (bags vs rockets vs large fields of Jet-Puff
marshmallows) after the parachute descent.

Blue skies

John


Basically like the Russians do it then?

I know it makes economic sense but we're losing something - certainly it
won't be like piloting a hypersonic vehicle back from orbit to a runway next
to the launch pad anyway.