Electronics & Avionics Flashcards

What is the primary purpose of a dual-deployment altimeter in a high-power rocket?

Answer: To fire drogue at apogee and main at a lower altitude

Dual-deployment altimeters fire a drogue parachute at apogee and a main parachute at a preset lower altitude to control descent rate.

Which battery type is most commonly recommended for powering avionics bays in high-power rocketry due to its stable discharge curve?

Answer: 9V lithium

9V lithium batteries are preferred for avionics because they maintain stable voltage under load and perform reliably across temperature extremes.

What does 'continuity' indicate on an altimeter's pre-launch status check?

Answer: An electrical circuit through the e-match or initiator is complete

Continuity means current can flow through the e-match circuit, confirming the pyrotechnic initiator is properly connected and functional.

When installing an avionics bay, why must the vent holes be positioned away from the fin can area?

Answer: To prevent motor exhaust pressure from triggering false apogee detection

Motor exhaust can pressurize the airframe near the fin can; vent holes placed there could cause the altimeter to detect a false pressure event and fire pyros prematurely.

What is the function of a 'shunt' or 'shorting plug' used with e-match circuits before flight?

Answer: It short-circuits the e-match to prevent accidental ignition

A shorting plug bridges the e-match leads together, preventing any stray current from accidentally firing the pyrotechnic charge during handling.

In rocketry avionics, what does 'arming altitude' refer to?

Answer: The minimum altitude the rocket must exceed before pyro channels are enabled

Arming altitude is a programmable threshold that prevents the altimeter from firing pyro channels unless the rocket has climbed above a set altitude, avoiding ground-level misfires.

Which wiring practice is critical to prevent RF interference from triggering e-matches in high-power rocketry electronics?

Answer: Twisting pyro lead wires together and keeping runs short

Twisting pyro lead wires cancels induced electromagnetic fields and keeping runs short minimizes the loop area that can act as an antenna.