Why should the roll program position the shuttle's nose to the east?
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4
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The roll program occurred during a shuttle launch for the following reasons:
(...)
Orienting the shuttle more parallel toward the ground with the nose to the east.
But why east?
launch launch-sequence
add a comment |
up vote
4
down vote
favorite
The roll program occurred during a shuttle launch for the following reasons:
(...)
Orienting the shuttle more parallel toward the ground with the nose to the east.
But why east?
launch launch-sequence
2
Possible duplicate of How does the roll maneuver allow more mass to be lifted into orbit?
– SF.
Dec 4 at 13:07
(long story short: utilizing the speed of rotation of Earth as a part of orbital velocity. This choice of direction sheds some 200-300m/s off the delta-V required to orbit.)
– SF.
Dec 4 at 13:09
3
I disgree with the duplicate topic votes. That topic has some relevant information, but doesn't explain why launches were aimed to the East.
– Hobbes
Dec 4 at 13:53
add a comment |
up vote
4
down vote
favorite
up vote
4
down vote
favorite
The roll program occurred during a shuttle launch for the following reasons:
(...)
Orienting the shuttle more parallel toward the ground with the nose to the east.
But why east?
launch launch-sequence
The roll program occurred during a shuttle launch for the following reasons:
(...)
Orienting the shuttle more parallel toward the ground with the nose to the east.
But why east?
launch launch-sequence
launch launch-sequence
edited Dec 4 at 17:45
jpaugh
1055
1055
asked Dec 4 at 12:29
Marian Paździoch
1512
1512
2
Possible duplicate of How does the roll maneuver allow more mass to be lifted into orbit?
– SF.
Dec 4 at 13:07
(long story short: utilizing the speed of rotation of Earth as a part of orbital velocity. This choice of direction sheds some 200-300m/s off the delta-V required to orbit.)
– SF.
Dec 4 at 13:09
3
I disgree with the duplicate topic votes. That topic has some relevant information, but doesn't explain why launches were aimed to the East.
– Hobbes
Dec 4 at 13:53
add a comment |
2
Possible duplicate of How does the roll maneuver allow more mass to be lifted into orbit?
– SF.
Dec 4 at 13:07
(long story short: utilizing the speed of rotation of Earth as a part of orbital velocity. This choice of direction sheds some 200-300m/s off the delta-V required to orbit.)
– SF.
Dec 4 at 13:09
3
I disgree with the duplicate topic votes. That topic has some relevant information, but doesn't explain why launches were aimed to the East.
– Hobbes
Dec 4 at 13:53
2
2
Possible duplicate of How does the roll maneuver allow more mass to be lifted into orbit?
– SF.
Dec 4 at 13:07
Possible duplicate of How does the roll maneuver allow more mass to be lifted into orbit?
– SF.
Dec 4 at 13:07
(long story short: utilizing the speed of rotation of Earth as a part of orbital velocity. This choice of direction sheds some 200-300m/s off the delta-V required to orbit.)
– SF.
Dec 4 at 13:09
(long story short: utilizing the speed of rotation of Earth as a part of orbital velocity. This choice of direction sheds some 200-300m/s off the delta-V required to orbit.)
– SF.
Dec 4 at 13:09
3
3
I disgree with the duplicate topic votes. That topic has some relevant information, but doesn't explain why launches were aimed to the East.
– Hobbes
Dec 4 at 13:53
I disgree with the duplicate topic votes. That topic has some relevant information, but doesn't explain why launches were aimed to the East.
– Hobbes
Dec 4 at 13:53
add a comment |
1 Answer
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oldest
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up vote
10
down vote
The phrase 'with the nose to the east' is a shorthand. The direction depended on the orbital inclination chosen for the mission.
- Missions to the ISS have to match the 51.6° inclination of the ISS
- the possible inclinations are limited by the launch location: from Cape Canaveral, you have to launch over water, so in a direction roughly between North-East and South.
You usually want to launch to the East (as opposed to launching to the West) because of the Earth's rotation to the East. If you launch to the East, you get part of your orbital speed (about 300 m/s on the equator) 'for free'.
The Shuttle needed to perform a roll program to get to the launch inclination: the launch pad is at a fixed angle that usually doesn't match the launch inclination, so you need to change course (preferably just after launch when your speed is low and the energy cost of the maneuver is lowest).
So, this is a bit more complicated. If this was all there was to the story, you could must have a yaw program and yaw to the east. In reality, the roll program orients the stack aerodynamically with the comm antennas (on the top of the orbiter) facing down -- a "heads down" ascent. Later in the program, there were plans to do a "heads up" ascent out of Vandenberg, but it never happened.
– Erik
Dec 11 at 3:06
add a comment |
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1 Answer
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active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
10
down vote
The phrase 'with the nose to the east' is a shorthand. The direction depended on the orbital inclination chosen for the mission.
- Missions to the ISS have to match the 51.6° inclination of the ISS
- the possible inclinations are limited by the launch location: from Cape Canaveral, you have to launch over water, so in a direction roughly between North-East and South.
You usually want to launch to the East (as opposed to launching to the West) because of the Earth's rotation to the East. If you launch to the East, you get part of your orbital speed (about 300 m/s on the equator) 'for free'.
The Shuttle needed to perform a roll program to get to the launch inclination: the launch pad is at a fixed angle that usually doesn't match the launch inclination, so you need to change course (preferably just after launch when your speed is low and the energy cost of the maneuver is lowest).
So, this is a bit more complicated. If this was all there was to the story, you could must have a yaw program and yaw to the east. In reality, the roll program orients the stack aerodynamically with the comm antennas (on the top of the orbiter) facing down -- a "heads down" ascent. Later in the program, there were plans to do a "heads up" ascent out of Vandenberg, but it never happened.
– Erik
Dec 11 at 3:06
add a comment |
up vote
10
down vote
The phrase 'with the nose to the east' is a shorthand. The direction depended on the orbital inclination chosen for the mission.
- Missions to the ISS have to match the 51.6° inclination of the ISS
- the possible inclinations are limited by the launch location: from Cape Canaveral, you have to launch over water, so in a direction roughly between North-East and South.
You usually want to launch to the East (as opposed to launching to the West) because of the Earth's rotation to the East. If you launch to the East, you get part of your orbital speed (about 300 m/s on the equator) 'for free'.
The Shuttle needed to perform a roll program to get to the launch inclination: the launch pad is at a fixed angle that usually doesn't match the launch inclination, so you need to change course (preferably just after launch when your speed is low and the energy cost of the maneuver is lowest).
So, this is a bit more complicated. If this was all there was to the story, you could must have a yaw program and yaw to the east. In reality, the roll program orients the stack aerodynamically with the comm antennas (on the top of the orbiter) facing down -- a "heads down" ascent. Later in the program, there were plans to do a "heads up" ascent out of Vandenberg, but it never happened.
– Erik
Dec 11 at 3:06
add a comment |
up vote
10
down vote
up vote
10
down vote
The phrase 'with the nose to the east' is a shorthand. The direction depended on the orbital inclination chosen for the mission.
- Missions to the ISS have to match the 51.6° inclination of the ISS
- the possible inclinations are limited by the launch location: from Cape Canaveral, you have to launch over water, so in a direction roughly between North-East and South.
You usually want to launch to the East (as opposed to launching to the West) because of the Earth's rotation to the East. If you launch to the East, you get part of your orbital speed (about 300 m/s on the equator) 'for free'.
The Shuttle needed to perform a roll program to get to the launch inclination: the launch pad is at a fixed angle that usually doesn't match the launch inclination, so you need to change course (preferably just after launch when your speed is low and the energy cost of the maneuver is lowest).
The phrase 'with the nose to the east' is a shorthand. The direction depended on the orbital inclination chosen for the mission.
- Missions to the ISS have to match the 51.6° inclination of the ISS
- the possible inclinations are limited by the launch location: from Cape Canaveral, you have to launch over water, so in a direction roughly between North-East and South.
You usually want to launch to the East (as opposed to launching to the West) because of the Earth's rotation to the East. If you launch to the East, you get part of your orbital speed (about 300 m/s on the equator) 'for free'.
The Shuttle needed to perform a roll program to get to the launch inclination: the launch pad is at a fixed angle that usually doesn't match the launch inclination, so you need to change course (preferably just after launch when your speed is low and the energy cost of the maneuver is lowest).
answered Dec 4 at 14:05
Hobbes
85k2238384
85k2238384
So, this is a bit more complicated. If this was all there was to the story, you could must have a yaw program and yaw to the east. In reality, the roll program orients the stack aerodynamically with the comm antennas (on the top of the orbiter) facing down -- a "heads down" ascent. Later in the program, there were plans to do a "heads up" ascent out of Vandenberg, but it never happened.
– Erik
Dec 11 at 3:06
add a comment |
So, this is a bit more complicated. If this was all there was to the story, you could must have a yaw program and yaw to the east. In reality, the roll program orients the stack aerodynamically with the comm antennas (on the top of the orbiter) facing down -- a "heads down" ascent. Later in the program, there were plans to do a "heads up" ascent out of Vandenberg, but it never happened.
– Erik
Dec 11 at 3:06
So, this is a bit more complicated. If this was all there was to the story, you could must have a yaw program and yaw to the east. In reality, the roll program orients the stack aerodynamically with the comm antennas (on the top of the orbiter) facing down -- a "heads down" ascent. Later in the program, there were plans to do a "heads up" ascent out of Vandenberg, but it never happened.
– Erik
Dec 11 at 3:06
So, this is a bit more complicated. If this was all there was to the story, you could must have a yaw program and yaw to the east. In reality, the roll program orients the stack aerodynamically with the comm antennas (on the top of the orbiter) facing down -- a "heads down" ascent. Later in the program, there were plans to do a "heads up" ascent out of Vandenberg, but it never happened.
– Erik
Dec 11 at 3:06
add a comment |
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Possible duplicate of How does the roll maneuver allow more mass to be lifted into orbit?
– SF.
Dec 4 at 13:07
(long story short: utilizing the speed of rotation of Earth as a part of orbital velocity. This choice of direction sheds some 200-300m/s off the delta-V required to orbit.)
– SF.
Dec 4 at 13:09
3
I disgree with the duplicate topic votes. That topic has some relevant information, but doesn't explain why launches were aimed to the East.
– Hobbes
Dec 4 at 13:53