rocket_recovery_system_failure_modes
Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision | |||
|
rocket_recovery_system_failure_modes [2016/05/01 21:17] dw444 |
rocket_recovery_system_failure_modes [2016/09/02 14:29] (current) dw444 |
||
|---|---|---|---|
| Line 7: | Line 7: | ||
| - Shock cords about 5m to reduce shock loads. | - Shock cords about 5m to reduce shock loads. | ||
| - Place chute so that nose and tail sections don't bash each other on decent. | - Place chute so that nose and tail sections don't bash each other on decent. | ||
| - | - Ensure chute compartment is sufficiently sealed so that it can pressurize, primarily between the altimeter bay which should be well vented. | + | - Ensure chute compartment is sufficiently sealed so that it can pressurise, primarily between the altimeter bay which should be well vented. |
| - | - Motor is retention inadequate, motor is ejected rather than chute. | + | - Motor retention inadequate, resulting in motor being ejected rather than chute. |
| - Flight computer must signal continuity on pad. | - Flight computer must signal continuity on pad. | ||
| - Flight computer can signal continuity but have damaged capacitor so not fire, ground test firing circuit if possible. | - Flight computer can signal continuity but have damaged capacitor so not fire, ground test firing circuit if possible. | ||
| Line 14: | Line 14: | ||
| - Don't use smokeless powder, it is too pressure sensitive. Blackpowder substitutes behave differently and should be avoided | - Don't use smokeless powder, it is too pressure sensitive. Blackpowder substitutes behave differently and should be avoided | ||
| - Make sure e-matches are well clamped in screw terminals. | - Make sure e-matches are well clamped in screw terminals. | ||
| - | - Use acceleration tolerant switches. | + | - Use acceleration tolerant switches, key switches are good. |
| - Align switches perpendicular to axis to avoid acceleration effects. | - Align switches perpendicular to axis to avoid acceleration effects. | ||
| - | - Shock cord not strong enough, assume 20g loads | + | - Shock cord not strong enough, assume 20g loads (probably excessive) |
| - | - Use good knots, bowline and barrel knots. | + | - Use kevlar cord (heat resistant) next to ejection charge and nylon cord or tape to reduce shock load. |
| + | - Use good knots, bowlines, barrel knots and fig 8 for cord, tape knots and overhands for tape. | ||
| - Use tape to pad kevlar cord where it leaves body tube to avoid tube damage "zipper effect" | - Use tape to pad kevlar cord where it leaves body tube to avoid tube damage "zipper effect" | ||
| - | - Ground test | + | - Ground test every deployment three times, to check for repeatability |
| - | - Ejection charges are best mounted centrally on bulkheads, use eyenuts on the end of studding. | + | - Ejection charges are best mounted centrally on bulkheads, use eyenuts on the end of studding if required. |
| - Only use masking tape to adjust fits, other tape generally binds worse. | - Only use masking tape to adjust fits, other tape generally binds worse. | ||
| - Check friction in joints, it can change. | - Check friction in joints, it can change. | ||
| Line 26: | Line 27: | ||
| - Compartments vented so that reduced ambient pressure doesn't cause premature separation. | - Compartments vented so that reduced ambient pressure doesn't cause premature separation. | ||
| - Vent altimeter bays symmetrically to avoid false readings from wind. | - Vent altimeter bays symmetrically to avoid false readings from wind. | ||
| - | - Ensure ejection charge not going to change due to acceleration. | + | - Ensure ejection charge not going to change due to acceleration (ie use wadding). |
| - Use nylon shear pins (M2) to stop main deploying at drogue deployment. | - Use nylon shear pins (M2) to stop main deploying at drogue deployment. | ||
| - | - A shear pin may stop the drag on the fins after motor burn out causing separation, has this ever happened? | + | - A shear pin can be used to stop the drag on the fins at motor burn out causing separation, has this ever happened? |
rocket_recovery_system_failure_modes.txt · Last modified: 2016/09/02 14:29 by dw444
Page Tools
Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 3.0 Unported
