NAR HPR Electronics & Avionics 3

Question 1

What is the recommended method for securing an altimeter sled inside an avionics bay to prevent vibration damage?

Accepted Answer

Foam padding and standoffs with nylon screws

Answer

Foam padding absorbs vibration and shock while nylon standoffs and screws secure the sled without creating rigid stress points that could crack the board.

Question 2

Why do some NAR HPR flyers use two independent altimeters with separate battery supplies?

Accepted Answer

Redundancy ensures recovery deployment if one system fails

Answer

Redundant independent altimeters with separate power supplies ensure parachute deployment even if one altimeter or battery fails during flight.

Question 3

What parameter do most barometric altimeters use to detect apogee?

Accepted Answer

Rate of pressure change transitioning from decreasing to increasing

Answer

Barometric altimeters detect apogee when atmospheric pressure stops decreasing and begins increasing, indicating the rocket has stopped climbing.

Question 4

What is the purpose of a 'motor delay' setting available on some avionics systems?

Accepted Answer

It prevents apogee detection for a set time to avoid triggering during fast coast phases

Answer

A motor delay (or lockout time) prevents false apogee detection caused by pressure transients during the motor burn coast transition.

Question 5

Which connector type is most commonly used in HPR avionics bays for pyro circuit connections due to its positive locking mechanism?

Accepted Answer

JST or Deans connectors with locking tabs

Answer

JST or Deans-style connectors with positive locking tabs resist vibration-induced disconnection and are compact enough for tight avionics bays.

(NAR HPR) NAR High-Power Rocketry Certification Practice Test

(NAR HPR) NAR High-Power Rocketry Certification Practice Test

NAR HPR Electronics & Avionics 3