Telemega issue

[Ric]

I recently flew a Telemega which failed to ignite the ejection charge for the main parachute. Fortunately the RRC3 provided backup. I am attaching the data file for the flight as it appears to show transient voltage dropouts for the main. The wiring is good which leads me to believe there is something funny going on with the TM. Is there anyone out there who can explain those readings?

 

[SparkyVT]

I recently flew a Telemega which failed to ignite the ejection charge for the main parachute. Fortunately the RRC3 provided backup. I am attaching the data file for the flight as it appears to show transient voltage dropouts for the main. The wiring is good which leads me to believe there is something funny going on with the TM. Is there anyone out there who can explain those readings?

What kind of battery were you using to power the TM?

 

[Ric]

What kind of battery were you using to power the TM?

The 3.7v 1000mah battery it came with. I use MJG electric matches for the pyro charges.

 

[SparkyVT]

Can you send a screenshot of the voltage dropouts? I cant read that file.

Was there another ejection charge on the apogee, or was the main parachute the only event the TM was supposed to do? If there was an apogee charge, did the voltage drop in a similar fashion for that event?

You say "transient voltage dropouts" for the main. Did the TM reset iteself in flight due to power loss? Or did it just fail to fire the main? Was there any chance the e-match leads were touching? That would be a very common error that seems to fit what you describe. Also, how are your e-matches secured? Terminal blocks? Sometimes after a lot of flights the connectors can get a buildup of carbon that can create a short.

Have you test-fired the system since the failure to see if you can recreate the problem? Its also possible you had a bad e-match. Its rare, but not unheard of.