Attempting my L1 in Berwick 8/17/2013

Well, the Super DX3 is about as ready as it will get, so I'm heading to the big field in Berwick to join the Moose and Squirrel flyers and hopefully be allowed my L1 attempt. I know we have several joint members - anyone plan on being up there this weekend?

The only sticky part of this is that I am required to assemble my Aerotech H123W-M in the presence of a member of the cert team. Haven't quite figured out how I am going to keep dirt and wind from screwing that procedure up whilst sitting in the middle of a field...

Hope to see some CMASS'rs up there on Saturday.

- Matt

Thanks Kenn. I will print out the Open Rocket sim results and bring them. I have a table that I bring to launches, so I'll at least have a stable flat surface to keep things organized and hopefully clean. Will add 'roll of paper towels' to the launch kit, and maybe the top of a big shoebox to keep the parts in one place. This is going to be fun!

- Matt

Matt, I'll be there with my son and will be happy to share a table and observe if needed. Just look for a Gray minivan. Curtis

Well, unfortunately for the rest of humanity, I am now legally allowed to send increasingly large and powerful objects ever higher into the sky. L1 success!

I made two attempts yesterday at Berwick. The first on my originally chosen load of Aerotech H123 (drilled to ~7s delay) was a picture perfect takeoff, flight, and ejection, but unfortunately the nose cone fell off at separation. This was not a shock cord failure - the nose is just friction fit, and it popped off when the shock cord was at maximum extension. Everything was recovered and able to fly again, but no L1. Jolly Logic II said 1159ft altitude, which agreed very well with my OR simulation.

The second was a bit of a field 'cob job'. First, much more tape on the nose to fit it (plus a last minute layer or two around the seam - thanks to Kenn B for the suggestion). After speaking with Jason at AMW, I opted to fit a 29mm 166-H163 CTI (7s delay) motor into my 38mm mount using an adapter. Now, I use the Aeropack retainer, so in this configuration the adapter has positive retention, but the motor needed to be friction fit into the adapter (plus I added a few layers of tape round the aft end to tape the end closure of the motor to the end of the adapter.) Guy W. witnessed and provided guidance on my motor assembly, Scott from MMMSC was RSO and witness and let me fly - very good flight, topping out at an (expected) lower altitude of 749 ft according to the Jolly Logic II, perfect recovery, and one very happy rocketeer!

At home last night, I opted to install two plastic rivets to secure the nose cone. They are the removable type in case I ever need to adjust the nose weight. That nose will not pop off any time soon.

Assembling the Aerotech was fun (thanks to an L3 named Howard for tips and loaning me some proper grease) and the motor performed well. Assembling the CTI was not challenging, so I can see why many opt for their motors. I ordered a 3-grain 38mm CTI casing and a spacer from AMW, so now I'll have Aerotech and CTI options.

Many thanks to everyone who gave me construction tips (and flight tips yesterday!). That Super DX3 bird is rock solid and a very nice flyer!

Thanks,
- Matt

Congratulations!

Good job on the L1.