Today's launches were both highly successful and terribly depressing. In fact, I'm hoping for some input from some of the members that have had experience with Aerotech RMS. I'll start with the high points of the day first. I launched my Leviathan on it's maiden flight today. In a word: WOW! The flight went off without a hitch on an Estes SU F50-6T.:grin: I used a Sonic Igniter and an Estes E launch controller with all of it's 6 volts. I then set up for a 2nd launch, this time on a RMS F22-7J in my new 29/40-120 case. For this I switched to a 12v controller; a Pratt Hobby Go Box hooked up to an Eveready 12v 926 lantern battery. The controller indicated continuity, but nothing happened when I hit the button. I troubleshooted for shorts, and inspected the copperhead igniter - the nichrome wasn't burned at all - and reinserted it, but still no launch. The lead was taped correctly and there was continuity, so I suspect that the copperhead was faulty. Unfortunately, I didn't have another one with me so I scuttled that launch and brought the loaded case home. I have noted past rants about these igniters from other members.
Next up was my Semroc Ranger on 3 B6-4s. This rocket launched fine using standard Estes igniters last summer at a club launch with their beefy launch system. I went to a 12v system so I could launch it on my own, but last time when I set it up to launch, the engines would not light. Could find no obvious short, but it was a no go. When I got home I pulled the igniters out - all connected in parallel - and connected the controller. All three of them burned well. I don't know why they didn't when inserted in the motors. Anyway, today I tried again using Quest Q2G2 igniters since they are low resistance, and all 3 motors lit. Great launch and recovery!:grin:
Next was my SLS Javelin on an RMS E187W. Two weeks ago This rocket launched beautifully on this reload, but the engine hook failed and I lost the 24/40 case when it kicked out. I recovered the rocket and last week I retrofitted it with an Aeropack threaded style retainer - good advice from another TRF member. This time though the launch was a disaster, and I'm not even sure what happened because the rocket was lost.:sad: Here's what I observed: The motor ignited normally. The controller wire alligator clips didn't disconnect from the copperhead ignitor and the rocket pulled the wiring along with it which caused an unstable launch. The rocket quickly picked up speed and became stable, but it's angle of attack was not even 45 degrees, more like about 30. With all the smoke from the White lightning propellant, I lost sight of the rocket and couldn't track it. Some other people on the field tried to track it, but I got conflicting reports on where the rocket may have ended up. I heard no ejection charge fire, and I think the Javelin likely pranged ballistic into the ground or the thick brush to the south east of the field. I looked for it for a long time thinking parts of it might be salvageable like the motor case and the engine retainer, but no luck.
Since I don't have the rocket to inspect, I have to theorize. Could the red cap which holds the igniter in place not have blown off with the engine exhaust; maybe just burned through, and the igniter stayed in place pulling the wiring harness along with the rocket? It pulled the plug right out of the launch controller. I'm new to RMS and am not familiar with common and not so common problems with reloads. If this is what happened, this makes me nervous about using the red caps to hold the igniters in place. They do fit very tightly. Maybe the Estes method of using plain old masking tape would be safer. In any case RIP SLS Javelin. That rocket will be missed.:sigh:
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