SPACECRAFT SYSTEMS PART 1&2
QUESTIONS WITH COMPLETE PASSED
SOLUTIONS!!
1 of 97
Term
What is Mission Analysis and Design?
What is the first step and what is important to identify?
Give this one a try later!
the iterative study of all possible options and configurations until the best
compromise architecture is found.
The first step is the feasibility analysis and the identification of viable
, concept options. It is important to identify the non-tradable constraints
early on - these are said to 'drive' the design - and then to adjust the other
parameters.
Instead of just thermally-expanding some of the propellant, we could bleed
some off and burn it.
Regenerative cooling is still used, but a separate combustion chamber creates
the turbine head.
The exhaust is dumped overboard. Again, this is an open cycle.
Has two turbines driving two pumps at different speeds.
The UK's ATC is based at the Royal Observatory, Edinburgh, and one of
Glasgow's particular strengths is the CubeSat architecture.
Pointing (precision, accuracy, speed, endurance) - AOCS
Delta-V (impulse, mass/power-efficiency, thrust) - Propulsion
Power (maximum, minimum, endurance, availability) - Power
Mechanics (mass, vibration, cost, resilience) - Structure
Temperature (maximum, minimum, endurance) - TCS
Data (speed, fidelity, resilience) comms and OBDH
Human factors (health, psychology, law, ethics) - LS
Don't know?
2 of 97
Term
Solid motors:
As the engine burns out, falling ........ and..........will probably cause
combustion to fail before the ........ This waste is called..........Naturally,
the point at which the flame will extinguish in ....... conditions is hard
,to predict.
Predicted ...... zones are sometimes replaced with ......l to increase
confidence in ...... and ....... shutdown. This is important because, if we
are staging, we do not want to drop a ....... due to the risk of...........The
........ will accelerate much faster, even with ..........., than the heavy
upper stage. So, when staging, ......... should be complemented by
........
Give this one a try later!
As the engine burns out, falling pressure and temperature will probably
cause combustion to fail before the last propellant is consumed. This waste
is called slivers. Naturally, the point at which the flame will extinguish in
borderline conditions is hard to predict.
Predicted sliver zones are sometimes replaced with dummy material to
increase confidence in prompt and predictable shutdown. This is important
because, if we are staging, we do not want to drop a still-thrusting lower
stage due to the risk of re-collision. The near- empty lower stage will
accelerate much faster, even with faltering combustion, than the heavy
upper stage. So, when staging, ullage motors should be complemented by
retros...
Between the firing of stages, there will be a period of weightlessness, during
which the fuel will float freely in our tanks.
How can we settle this sloshing?
We fire small solid rockets to provide just enough acceleration to put the fuel at
the bottom of the tank. This is called an ullage burn.
the iterative study of all possible options and configurations until the best
compromise architecture is found.
, The first step is the feasibility analysis and the identification of viable concept
options. It is important to identify the non-tradable constraints early on - these
are said to 'drive' the design - and then to adjust the other parameters.
Aerodynamic drag: Our rocket will have had to punch up through the
atmosphere. Drag will decrease with density, but increase with velocity. The
maximum drag occurs max-Q, generally around 10-15 km. We may throttle-down
near max-Q, and throttle-up afterwards.
Gravity drag: We have to increase the potential energy of our machine, and
this uses some energy too. A shallower trajectory at high altitude will result in
less of the thrust vector being directed against gravity.
Steering losses: Some energy must be used to manage our trajectory.
launch profile. This is very complicated!
Don't know?
3 of 97
Definition
Aerodynamic drag: Our rocket will have had to punch up
through the atmosphere. Drag will decrease with density, but
increase with velocity. The maximum drag occurs max-Q,
generally around 10-15 km. We may throttle-down near max-Q,
and throttle-up afterwards.
Gravity drag: We have to increase the potential energy of our
machine, and this uses some energy too. A shallower trajectory
at high altitude will result in less of the thrust vector being
directed against gravity.
Steering losses: Some energy must be used to manage our
trajectory.
QUESTIONS WITH COMPLETE PASSED
SOLUTIONS!!
1 of 97
Term
What is Mission Analysis and Design?
What is the first step and what is important to identify?
Give this one a try later!
the iterative study of all possible options and configurations until the best
compromise architecture is found.
The first step is the feasibility analysis and the identification of viable
, concept options. It is important to identify the non-tradable constraints
early on - these are said to 'drive' the design - and then to adjust the other
parameters.
Instead of just thermally-expanding some of the propellant, we could bleed
some off and burn it.
Regenerative cooling is still used, but a separate combustion chamber creates
the turbine head.
The exhaust is dumped overboard. Again, this is an open cycle.
Has two turbines driving two pumps at different speeds.
The UK's ATC is based at the Royal Observatory, Edinburgh, and one of
Glasgow's particular strengths is the CubeSat architecture.
Pointing (precision, accuracy, speed, endurance) - AOCS
Delta-V (impulse, mass/power-efficiency, thrust) - Propulsion
Power (maximum, minimum, endurance, availability) - Power
Mechanics (mass, vibration, cost, resilience) - Structure
Temperature (maximum, minimum, endurance) - TCS
Data (speed, fidelity, resilience) comms and OBDH
Human factors (health, psychology, law, ethics) - LS
Don't know?
2 of 97
Term
Solid motors:
As the engine burns out, falling ........ and..........will probably cause
combustion to fail before the ........ This waste is called..........Naturally,
the point at which the flame will extinguish in ....... conditions is hard
,to predict.
Predicted ...... zones are sometimes replaced with ......l to increase
confidence in ...... and ....... shutdown. This is important because, if we
are staging, we do not want to drop a ....... due to the risk of...........The
........ will accelerate much faster, even with ..........., than the heavy
upper stage. So, when staging, ......... should be complemented by
........
Give this one a try later!
As the engine burns out, falling pressure and temperature will probably
cause combustion to fail before the last propellant is consumed. This waste
is called slivers. Naturally, the point at which the flame will extinguish in
borderline conditions is hard to predict.
Predicted sliver zones are sometimes replaced with dummy material to
increase confidence in prompt and predictable shutdown. This is important
because, if we are staging, we do not want to drop a still-thrusting lower
stage due to the risk of re-collision. The near- empty lower stage will
accelerate much faster, even with faltering combustion, than the heavy
upper stage. So, when staging, ullage motors should be complemented by
retros...
Between the firing of stages, there will be a period of weightlessness, during
which the fuel will float freely in our tanks.
How can we settle this sloshing?
We fire small solid rockets to provide just enough acceleration to put the fuel at
the bottom of the tank. This is called an ullage burn.
the iterative study of all possible options and configurations until the best
compromise architecture is found.
, The first step is the feasibility analysis and the identification of viable concept
options. It is important to identify the non-tradable constraints early on - these
are said to 'drive' the design - and then to adjust the other parameters.
Aerodynamic drag: Our rocket will have had to punch up through the
atmosphere. Drag will decrease with density, but increase with velocity. The
maximum drag occurs max-Q, generally around 10-15 km. We may throttle-down
near max-Q, and throttle-up afterwards.
Gravity drag: We have to increase the potential energy of our machine, and
this uses some energy too. A shallower trajectory at high altitude will result in
less of the thrust vector being directed against gravity.
Steering losses: Some energy must be used to manage our trajectory.
launch profile. This is very complicated!
Don't know?
3 of 97
Definition
Aerodynamic drag: Our rocket will have had to punch up
through the atmosphere. Drag will decrease with density, but
increase with velocity. The maximum drag occurs max-Q,
generally around 10-15 km. We may throttle-down near max-Q,
and throttle-up afterwards.
Gravity drag: We have to increase the potential energy of our
machine, and this uses some energy too. A shallower trajectory
at high altitude will result in less of the thrust vector being
directed against gravity.
Steering losses: Some energy must be used to manage our
trajectory.
