There will be (3) questions on the actual exam from Section D's (9) question pool. For each question below, click on the circle next to the correct answer. When you have finished the test, Click the 'Score My Exam' button at the bottom of the page. Good luck!

Question D1
For a rocket to be stable, which of the following statements is true?

A. The center of pressure (CP) must be behind the center of gravity (CG)
B. The center of pressure (CP) must be in front of the center of gravity (CG)
C. The rocket must have fins
D. The length of the body tube must be at least 5 times the model diameter

Question D2
An unstable rocket can be made stable by:

A. Adding sufficient weight to the nosecone
B. Removing sufficient weight from the nosecone
C. Moving the fins sufficiently forward towards the nosecone
D. Making the rocket sufficiently shorter

Question D3
Rocket stability can be estimated by:

A. Center of pressure “Barrowman“ equations
B. “Cardboard cutout“ method
C. Determining the relative positions of the center of pressure and center of gravity
D. Stability cannot be estimated before a test flight

Question D4
A rocket’s center of pressure can be estimated by using:

A. The “Barrowman“ method
B. Finding the point where the model balances
C. “Cardboard cutout“ method
D. Both “A“ and “C“ above

Question D5
An unstable rocket can usually be made more stable by:

A. Using a shorter nosecone
B. Increasing the size of the aft fins
C. Using a larger, heavier rocket motor
D. Increasing the rocket diameter

Question D6
During boost a rocket powered by a solid rocket motor tends to:

A. Become less stable in flight
B. Become more stable in flight
C. Have no change in stability
D. Become unstable

Question D7
Which of the following can cause unstable flight?

A. Weak tubes or couplers that permit airframe bending
B. Misaligned motor mount tube or motor nozzle
C. Inadequate airspeed leaving the launch tower on a breezy day
D. All of the above

Question D8
As a rule of thumb, how far should the center of pressure be from the center of gravity?

A. The center of pressure should be at the same location as the center of gravity
B. The center of pressure should be at least 1.0 body tube diameters behind the center of gravity
C. The center of pressure should be at least 1.0 body tube diameters ahead of the center of gravity
D. The center of pressure should be 1.0 body tube diameters ahead of the fin leading edge; the center of gravity does not matter

Question D9
The definition of Positive Stability in regards to a rocket is:

A. Where the center of gravity (CG) is located ahead (forward) of the center of pressure (CP)
B. Where the center of gravity (CG) and the center of pressure (CP) lie at the same locations
C. Where the center of gravity (CG) is located behind (aft) of the center of pressure (CP)
D. None of the above

Move to:

Section A

Section B

Section C

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