Proper process for preparing AV bay

[thehemi]

My AV bay is ready for bench testing with BP charges inside the rocket. Bench testing of the igniters was successful.

Items I will need to do in order to prepare the AV bay for testing (or flight):

Connect the battery (there's an on/off switch)
Connect the igniters
Pack the cups with BP

With safety in mind, is there a preferred order of operations? I think it mostly comes down to connecting the battery before or after setting up the BP charges?

Thanks,
Scott

 

[AndrewGil]

I go battery in, quick systems test. Then switch(s) off, close ebay, wire ematches to terminals on bulkplates, then weigh out BP and load.

 

[waltr]

Battery in with switch off. Connect Ematches (direct to Eggtimer altimeters). Switch on to check system and continuity. Switch off and close Ebay.
Load BP charges, check chutes, close tubes and insert rivets and shear pins.
Go to RSO table.
Place rocket on rail, pivot to launch position. Turn on switch to arm (or arm through WiFi).

 

[pathtouch]

Battery in with switch off. Connect Ematches (direct to Eggtimer altimeters). Switch on to check system and continuity. Switch off and close Ebay.
Load BP charges, check chutes, close tubes and insert rivets and shear pins.
Go to RSO table.
Place rocket on rail, pivot to launch position. Turn on switch to arm (or arm through WiFi).

This is the best method in my opinion because if you have a sketchy e-match and a continuity check sets it off it won’t blow up an ejection charge in your face.

Story time, I was using a half dead lipo and for whatever reason my altimeters were acting messed up and set off my MJG initiators four times in a row when powering on before I realized what was happening. If it had been in a chargewell of black powder I’d be rather frazzled.

 

[thehemi]

Great advice, thank you everyone!

This leads me to one more question while we're on the topic. After pivoting the rail, install motor igniter or arming eBay first? I'm debating in my mind which one would be a worse malfunction?

Thanks,
Scott

 

[kjhambrick]

Pivot the Rail, arm the AV-Bay then install ignitors.

Edit: See Q49 in the Tripoli Current Advanced Study Guide

-- kjh

 

[Kane]

Great advice, thank you everyone!

This leads me to one more question while we're on the topic. After pivoting the rail, install motor igniter or arming eBay first? I'm debating in my mind which one would be a worse malfunction?

Thanks,
Scott

Arm your deployment electronics first. First reason: you'll discover if there are any discontinuities or issues with your deployment setup prior to inserting the motor igniter. Second reason: if, for some reason, there is an unplanned ignition of your motor, you're not flying without deployments.
Also, be sure to touch the launch control leads together first before connecting to your igniter.

 

[David Schwantz]

Even better, do NOT install igniters until altimeters are armed and RTF.

 

[waltr]

This is the best method in my opinion because if you have a sketchy e-match and a continuity check sets it off it won’t blow up an ejection charge in your face.

Story time, I was using a half dead lipo and for whatever reason my altimeters were acting messed up and set off my MJG initiators four times in a row when powering on before I realized what was happening. If it had been in a chargewell of black powder I’d be rather frazzled.

Yea, happened at our local launch to a buddy. Everything installed and ready to go. Turned on altimeter and when it check continuity both BP charges fired while he was holding the rocket. No injury but sure did scare him.
Turned out something on the altimeter went BAD. I checked it and then we scraped it as this was cheaper than having it happen again.

Yes, Arm and get altimeter to give to all go signal before inserting motor igniter so that Recovery is working.

 

[Handeman]

This assumes a pull pin and screw switch are wired in series in the power to the altimeter(s)
install ematches on av-bay
turn on altimeter(s) via screw switch and check battery voltage and ematch continuity open av-bay and replace battery if below 8.9V
turn off altimeter(s) via screw switch
add BP
assemble rocket
install remove before flight (RBF) pull pins
turn on screw switches
at pad, mount rocket and set to launch position.
pull RBF pull pins to power up altimeter(s) and verify battery voltage and ematch continuity
Install igniter in motor
Connect controller leads to igniter and let the LCO do his/her thing.