NAR HPR Recovery Systems & Deployment 2

Question 1

Which altimeter feature is most critical for ensuring dual-deployment reliability in high-power rocketry?

Accepted Answer

Redundant independent pyro channels

Answer

Redundant independent pyro channels allow separate drogue and main chute events to fire independently, preventing a single point of failure.

Question 2

A barometric altimeter fails to fire the apogee charge. What is the most likely cause in a properly wired system?

Accepted Answer

Battery voltage dropped below altimeter threshold

Answer

Most altimeters have a minimum voltage requirement; a weak or depleted battery is the most common cause of failed pyro channel firing.

Question 3

What is the purpose of a 'shear pin' in a dual-deployment recovery system?

Accepted Answer

To hold the nosecone until ejection pressure shears it away

Answer

Shear pins hold the nosecone or payload section closed until sufficient ejection pressure breaks them, preventing premature deployment.

Question 4

When sizing a drogue parachute for a high-power rocket, the primary goal is to:

Accepted Answer

Slow the rocket to a safe speed for main deployment while limiting drift

Answer

The drogue slows the rocket from near-apogee speeds to a velocity safe for main chute deployment, while keeping descent fast enough to limit drift.

Question 5

NAR safety rules require that all recovery system wadding or baffles must be:

Accepted Answer

Flame-resistant and prevent hot gases from reaching the parachute

Answer

Wadding or baffles must be flame-resistant and protect the parachute from hot ejection gases to prevent melting or ignition.

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