Chapter 4 Self Test

Question 0

(019) 2. What provides a means to handle and transport the Atlas V CCB?

Answer 0

Aft transition structure

Question 1

(019) 1. What prevents the Atlas V liquid oxygen propellant tank from being filled to 100 percent?

Answer 1

The expansion and contraction properties of liquid oxygen.

Question 2

(019) 3. After the Atlas V’s CCB RD-180 engine starts up, what does it use to continue to operate?

Answer 2

The system uses RP-1 fuel from the main propellant tank, provided by the engine’s fuel pump.

Question 3

(019) 4. Why must the Atlas V centaur upper stage’s propellant tanks be pressurized, even when empty?

Answer 3

To maintain structural integrity

Question 4

(019) 5. What is the purpose of the charge segments and booster assemblies of the Atlas V centaur upper stage’s interstage adapter?

Answer 4

Upon initiation, the charge segments separate the CCB and the centaur. The booster assemblies keep the CCB from striking the centaur during and after separation.

Question 5

(019) 6. What is the purpose of the boat tail in the Atlas V 400-series payload fairing?

Answer 5

It adapts the diameter of the PLF (12.3 feet) down to the diameter of the centaur (10 feet).

Question 6

(019) 7. What is the purpose of the centaur forward load reactor (CFLR) in the Atlas V 500-series payload fairing (PLF)?

Answer 6

The CFLR keeps the top of the centaur and the payload centered in the PLF and increases the structural strength of the PLF.

Question 7

(019) 8. In addition to a core CBC, what does the Delta IV Heavy use to provide liftoff?

Answer 7

Two additional CBCs

Question 8

(019) 9. What is the purpose of the booster rocket separation motor on the Delta IV CBC?

Answer 8

To provide the thrust to propel the CBCs away from the launch vehicle during separation.

Question 9

(019) 10. How is roll control provided during a Delta IV’s main engine burn when only one CBC is used?

Answer 9

By vectoring the turbine exhaust gases

Question 10

(019) 11. What does the attitude control system (ACS) provide for the Delta IV second stage?

Answer 10

Provides roll control during main engine burn and pitch, yaw, and roll control during coast periods.

Question 11

(019) 12. What are the two configurations of Delta IV payload fairing?

Answer 11

Delta IV fairings are mostly bisector designs (two halves); however a tri-sector (three piece) fairing is available for payloads too large for the bisector fairing.

Question 12

(020) 1. What is an advantage of using solar power as an electrical source?

Answer 12

Solar cells require no additional energy source, such as chemicals or nuclear reaction, for power production.

Question 13

(020) 2. What are two disadvantages of using solar power?

Answer 13

Their low power generation capacity and solar panel orientation with respect to the sun.

Question 14

(020) 3. When does a secondary battery release it power?

Answer 14

When the satellite moves into the shadow of the earth, moon, or other planets.

Question 15

(020) 4. What missions would be better suited for nuclear powered spacecraft?

Answer 15

Those missions which either due to their length, increased power requirements, or distance from the sun, makes them better suited for the job.

Question 16

(020) 5. What is the challenge of a spacecraft’s thermal control subsystem?

Answer 16

To provide the proper heat transfer between all spacecraft elements so that the temperature-sensitive components remain within their specified temperature limits during all mission environmental conditions.

Question 17

(020) 6. What are heat sinks used for in a spacecraft’s thermal control system?

Answer 17

To conduct heat away from or to the component whose temperature is to be controlled.

Question 18

(020) 7. What kind of constraints is there when using phase changing materials as a passive thermal control?

Answer 18

They must be contained within leak proof compartments and they cannot prevent further temperature increase when all of the material is melted.

Question 19

(020) 8. What two things could cause an electric heater to operate on a spacecraft?

Answer 19

When temperatures fall below a predetermined level,the heaters turn on until the desired temperature is established. Radio commands from the satellite ground support/control facility can also operate some heaters.

Question 20

(020) 9. Why is liquid propellant used on a majority of satellites?

Answer 20

They allow satellite controllers to precisely control the satellite’s thrust and fire them multiple times.

Question 21

(020) 10. What is attitude?

Answer 21

The orientation of a spacecraft’s X, Y, and Z coordinate axes with respect to a known point (either on earth or in space).

Question 22

(020) 11. What kind of things causes irregular motion of a satellite, making station keeping difficult?

Answer 22

Atmospheric drag, gravity, solar winds

Question 23

(020) 12. What data would be considered primary payload data?

Answer 23

Meteorological, oceanographic, astronomical, and earth resources