Radio controlled backup pyros FTW

AllDigital

Well-Known Member
TRF Supporter
Joined
Jun 14, 2013
Messages
600
Reaction score
676
Location
SoCal
My son and I have been testing an experimental spring/latch recovery system that does not require BP. The test vehicle is a 90 pound 8" beast of a rocket. It has an 18' main and drogue out the top, using the spring and electronic latches and in the fin can it has a backup 14' main with pyros triggered by radio (our "FTS" backup). In the third test this weekend, the primary altimeters failed, so the nose did not separate. We held our breath watching the beast spin like a top, waiting for the FTS signal to trigger the backup chute. Happy to report she landed without a scratch.

Note this was done out at FAR, launched on a M-class sugar motor (KNSB), with everyone safely in bunkers.

 

Troy3003

Well-Known Member
Joined
Feb 11, 2021
Messages
305
Reaction score
235
Location
Shelbyville, KY
I understand your purpose for using the r/c Pyro setup and it does sound cool. On the other hand that seems to be a dangerous practice for the hobby (imo). Mainly because of how others outside of the hobby may perceive it nefarious in design.
 

Titan II

Well-Known Member
Joined
Aug 23, 2013
Messages
1,703
Reaction score
808
I understand your purpose for using the r/c Pyro setup and it does sound cool. On the other hand that seems to be a dangerous practice for the hobby (imo). Mainly because of how others outside of the hobby may perceive it nefarious in design.

Ridiculous. There are a lot more things we do the Karens of America could perceive a nefarious. I use RC activation as needed. Nice work OP.
 
Last edited:

Troy3003

Well-Known Member
Joined
Feb 11, 2021
Messages
305
Reaction score
235
Location
Shelbyville, KY
I would hardly call it ridiculous, you have seen the world lately right? People will have issue with anything you do anymore.
 

cerving

Owner, Eggtimer Rocketry
TRF Sponsor
TRF Supporter
Joined
Feb 3, 2012
Messages
5,932
Reaction score
4,453
R/C chute activation has its place, but for most projects it isn't all that effective. If you can't see the rocket, it's not much help, and it doesn't help with mechanical issues such as a stuck chute or nose cone either. I think a freefall detection like we put into the Quantum and Proton is more effective in most cases; if it detects that you're exceeding a set downward velocity, pop the main early. You'll drift, but you get your rocket back.
 

AllDigital

Well-Known Member
TRF Supporter
Joined
Jun 14, 2013
Messages
600
Reaction score
676
Location
SoCal
I think a freefall detection like we put into the Quantum and Proton is more effective in most cases; if it detects that you're exceeding a set downward velocity, pop the main early. You'll drift, but you get your rocket back.
Yep. I would not normally advocate for remote controlled pyros, but in our testing for this rocket and the experimental recovery system it has proven the right solution (twice). Our flight on Saturday had an unusual profile. After apogee it went into a flat spin falling only at 100 fps, so a downward velocity trigger wouldn’t have helped. From a telemetry perspective it looked like it was under drogue, but we also had sensors indicating the the nose was still on during the fall. Also, we intentionally fly this test low and slow so we can easily see the whole flight and can manually deploy a backup chute if needed.
 

speed

Well-Known Member
Joined
Apr 15, 2009
Messages
123
Reaction score
70
I use a pager system like the RRS guys used years ago. Works well when needed! From Radio Shack and modified.
 

rocket_troy

Well-Known Member
TRF Supporter
Joined
Sep 9, 2013
Messages
822
Reaction score
538
Location
Melbourne, Australia
I'm one of those people who design and make everything for the rocket - electronics/pyroless recovery system/airframe/motors/motor components/propellant and even fuel and oxidizer on occasion. So R/C backup is a pretty important thing to have.

Anyway, congrats on the flights and recovery success.

Troy
 

Voyager1

Well-Known Member
TRF Supporter
Joined
Oct 23, 2015
Messages
1,105
Reaction score
504
Location
Australia
I would hardly call it ridiculous, you have seen the world lately right? People will have issue with anything you do anymore.
I agree, it’s not ridiculous, and it’s a valid concern. However, in these cases, the backup measures employed are appropriate. Safety should always take priority over the ignorance and perceptions of others.

Good work AllDigital!
 

plugger

Well-Known Member
Joined
Apr 30, 2009
Messages
759
Reaction score
450
I agree, it’s not ridiculous, and it’s a valid concern. However, in these cases, the backup measures employed are appropriate. Safety should always take priority over the ignorance and perceptions of others.

Good work AllDigital!
without getting into the politics of over there I feel confident that what matters most in this conversation is legality. and to my knowledge the above is not illegal. and if it was illegal I doubt radio enabled Altus Metrum FCs would have a 'test ignitor over the radio link' function. Same with the Missile Works WRC+, granted I'm not 100% on that one as I've not used one myself.
 
Top