3D Robotics Comment by Chris Anderson on April 9, 2012 at 11:37pm

Video please!!!!

Comment by Melih Karakelle on April 9, 2012 at 11:43pm

Max speed is lower than i expected. But i guess you will use bigger rocket motor for next launches. Am i right?
What is the yellow coating? kevlar? 

Comment by Ari Krupnik on April 9, 2012 at 11:50pm

Yellow stuff is zagi tape--mostly to protect the foam on landing, and to help me to see which side is up. It has a lot more drag than a typical rocket. It's also quite heavy for this motor. For first flight I'm quite happy with a low max latitude :=) I want it to walk before it goes orbital on me. Not sure how much speed the stock airframe can handle before is starts to flutter, strip servo gears, tear off the canopy, etc :=)

Chris: come to Moffett Field on April 21 and see the next launch for yourself! http://www.lunar.org/calendar.shtml#launches

Ari.

Comment by healthyfatboy on April 10, 2012 at 4:29am

Very nice Ari! I haven't been on RCG as much lately and have wondered what you were up to.

I too would like a video, mainly because I can't make it since I'm on the east coast.

Comment by Paul Bizard on April 10, 2012 at 8:30am

Very cool project !

I was dreaming of such a project 20 yeas ago !

Comment by Riccardo Kuebler on April 10, 2012 at 9:50am

mhmm, mine seems too much little for an autopilot.

Piloting those things is amazing anyway, isn't it ?

Nice project !

Comment by Ari Krupnik on April 10, 2012 at 11:53pm

The motor stays put. Here are some closeups of the motor mount. The original electric motor mount and the new rocket tube are interchangeable. I can swap them in and out in the field.

Comment by Ari Krupnik on April 10, 2012 at 11:57pm

The motor stays put. I have another, smaller rocket glider that does eject the motor, but there I mount the motor in the nose. Generally, you want a very forward CG on the boost, and move it back for glide. If you mount the motor in front, you can eject it at the apogee and it does the right thing with CG. The difficulty is that now you have a motor tube in front of the center of pressure, wish destabilizes you in yaw.

With a rear motor  mounting, you want to to keep the motor where it is. Ejecting it moves the CG /forward/ for glide, which is the opposite of what you want. I use a "plugged" motor that has no ejection charge.

Ari.

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