Props for down =advanced=

[Chuck Rudy]

Another question......anyone have any experience with helicopter recovery for heavy rockets, say over 30#? I've only ever seen one flight video (it was a K motor) and I'm thinking of..........becoming a propeller head.

Chuck

 

[rstaff3]

Is this an opportunity for non pyro recovery? Hold the props in place with a servo/solenoid and then possibly even deploy them with a servo?

 

[DynaSoar]

Originally posted by Chuck Rudy
Another question......anyone have any experience with helicopter recovery for heavy rockets, say over 30#? I've only ever seen one flight video (it was a K motor) and I'm thinking of..........becoming a propeller head.

Chuck

I tried to use a nice trimmed prop on a mid-sized bird, maybe 2 lbs as a passive helo recovery. The most trouble I had was in trying to get it to spin and not spin the rocket. It did terrible things to the shock cord; you know how the rubber band on a wind-up airplane gets double then triple then quadruple helically wrapped?

A powered prop with a counter-rotating flywheel, that might work. But probably far better to spin the bird than try to deal with the angular momentum problems.

 

[urbanek]

I've seen a really big autorotation recovery rocket that flew on a J. The rotors were made of fabric covered wire. It still broke the hub when it landed. The problem is that you have this heavy rocket spinning fast, and the rotor blades sticking way out. When the rocket touches down, the first rotor blad that touches the ground hits with a great deal of force and a lot of moment arm.

The rotor blade vs ground impact(s) are what stops the rocket, or rotor blades, from spinning and it's terrifically violent.

urbanek

 

[GL-P]

Could you have 2 rotors spinning in different directions like a Chinook helicopter

 

[Hospital_Rocket]

I was searching for Gyros (see my other thread) and ran across this site.

https://www.bestrc.com/helimax/hmxe4270.html

They list some carbon-fiber / glass composite blades.

My ony thought would be the extreme forces at the mounting point when they unfolded. Perhaps a drogue could deploy and the be released as soon as the orientation had been set after apogeee and the released to fall free as the blades deploy.

A