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Chapter 7
7.1 What is INCOSE?
7.2 In your own words give a definition for the requirements defining process.
INCOSE Systems Engineering Handbook v. 3.2 the requirements definition process main
purpose is to:
7.3 What is a Design Reference Mission?
7.4 What is a derived requirement?
7.5 The U.S. Army has a call for proposals to deliver a 400 kg payload to an altitude of
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40 km with a downrange distance impact point of at least 70 km. You are
evaluating the proposals for the Army. One proposed solution “requires” solid
rocket motors only. Would this be a derived requirement, a mission requirement,
or a design choice?
7.6 Give the three Rocket Design Rules and discuss what they mean.
7.7 Use OpenRocket to design a hobby rocket using an F class motor. The mission
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7.8 A rocket is 7 meters tall and 1.4 meters in diameter. Calculate the fineness. How
does it compare to a Delta IV?
7.9 If the rocket in Exercise 7.8 is made of 6061 aluminum that has a Young’s modulus,
E, of 69 GPa (69 x 109 N/m
2), a density of 2700 kg/m3, and we assume after
structure and tanks it has an effective wall thickness of 25mm, calculate the critical
pressure for buckling of the rocket.
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7.10 Use a computer program (such as Mathcad) to graph the critical pressure of the
rocket in Exercises 7.8 and 7.9 versus a wall thickness ranging from 1 to 50 mm.
Also, plot the mass of the rocket versus the wall thickness.
7.11 Use the Mathcad algorithm/code given in Section 7.2 to reanalyze Design
Reference Mission #2 but this time with a 300 kg payload. Note: feel free to
convert the Mathcad code to Matlab or any other software you prefer.
7.12 In Exercise 2.8 we studied the following rocket:
A rocket is launched with a burnout velocity of 75 m/sec, burnout altitude of 300
m, and a burnout range of 100 m. Assuming a flight path angle of 75°, calculate the
final range of the rocket when it impacts the ground.
Use OpenRocket to simulate as best you can the rocket in this Exercise. Simulate
and Plot your results.
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7.13 What does OpenRocket calculate for the maximum altitude reached by the rocket
in Exercise 2.8?
7.14 Design, build, and fly a rocket using any motor and materials of choice.