Robin Ultralight

[Mark Calder]

So I was looking for a good used Ballistic Chute, specifically a Second Chantz 550 or 600 soft pack chute. I found a Mini Max Project on Barnstormers in Phoenix for sale with the correct chute. I hate to say what we paid for the project, but it almost exactly equaled our fuel cost there and back. I made a deal with my Friend Ed and we split everything in half, he got the complete project with airframe, new carbon ground adjustable prop, Rotax 377 engine and 10 gallons of certified finish dope. I got the chute.

Today I packed up my Second Chantz Chute and shipped it back to the factory. They walked me through disarming the rocket and detonator. After 19 years that chute would have worked. The igniter was strong and the two rocket capsules made a cool fireworks display when we ignited them.

I have been going through a weight and Balance and asked my Friend Dan Rich to verify the static margin with the chute installed in the turtle deck. The neutral point was calculated to be 37.5% The aft CG with no fuel is 31% so that gives me at least a 12% static margin. Full fuel moved the CG to 22% The pilot is centered on the 25% chord point to reduce trim change with pilot weight variation.

I finished the L/H wing covering. Tomorrow I will rib stitch it. On Saturday I will put the base coat on the fabric. I plan on finishing all of the covered surfaces and then re rig everything. I will add weight to simulate the Chute and do a final weight and balance.

I also need to work with Second Chanz http://www.secondchantz.com/index.html to develop the 4 point bridle system. The chute is designed to be mounted on the roll over cage. The bridles will snake over the top of the longerons and run inside the fabric on one of the fabric stand offs. They will loop around the main wing box and the landing gear box. I can just imagine what will happen if that handle ever has to be pulled. You definitely don't want to use this chute for routine landings.

I'm starting to think my Landing gear might not be stiff enough. The fact that I am only mounting the gear at two points and allowing carry thru moment to pass between gears, is causing a rocking motion when the gear is full loaded. This was done on purpose because it allows greater deflection at the wheel and thus greater energy absorption. The gear also might not be stiff enough in the fore aft direction too, I believe I will be adding an additional 1/2" of width on the gear and redesigning the landing gear bulkhead to mount each gear leg at two points similar to a Cessna.