Chute needed for recovery of 20 lb dart with a vterminal of 210 fps

[jwhunter]

We (Green Launch) are working for the National Science Foundation and are launching a finned steel dart to 37 km altitude at the Yuma Proving Ground.
It will sample the atmosphere at that altitude and return to earth where the air sample will be recovered and sent to both UCSD and Harvard for analysis.

We have a high terminal velocity (210 fps) to minimize wind drift. The vehicle is extremely rugged so it should survive the impact phase.
Estimated soil penetration of around 1 meter.

We are looking for a compact but rugged parachute with the following properties:

• CD*Area=57.7 square inches (for example CD=1.5 and Diam=7")
• Storage volume is 3.5" long and 1.6" Diam. (7 cubic inches)
• Very simple shape with minimum lines.
• Chute is ejected on descent at 30 km altitude and has max Q at about 20 km. Max decelleration is 2 G's.

Our primary chute source has gone dark so we need to solve the chute issue in the next 2 weeks.

Any ideas or sources? Feel free to call or email me.

Thanks in any case.

Dr. John Hunter
CTO for Green Launch, Inc.
[email protected]
(619) 933-6678

 

[StreuB1]

https://wildmanrocketry.com/collections/parachutes/products/recon-recovery-drogue-12

Should come in around 160-180 FPS, likely more on the 180 side.

 

[jwhunter]

Thanks much. Am getting one.
Slightly concerned re heating since about Mach 1.4 at 20 km on descent. Any ideas of heating analysis or better
yet data on similar trajectories?

 

[StreuB1]

Little air at 20km so M1.4 will not have much heating capability.

 

[cls]

Kevlar, x form, like used on a drag racer.

 

[rharshberger]

Kevlar, x form, like used on a drag racer.

iirc Rocketman has some kevlar, mach chutes (or at least advertises them as such).

 

[Tractionengines]

+1 on Rocketman Parachutes... here are two links. Look them over then call and talk to Buddy. He checks in here once and a while.

Kevlar parachutes:
https://the-rocketman.com/kevlar/
Mach II Balistic parachutes:
https://the-rocketman.com/ballistic-parachutes/

@Buddy Michaelson can you help...?

 

[Neutronium95]

The packing volume constraints might exclude the Rocketman options. They tend to be pretty bulky. I wouldn't be concerned at all about heating on the way down. Mach 1.4 will put a lot of stress on the parachute, but it won't heat it up too much.

 

[cls]

Kevlar for shock loads, not for heating.

 

[jwhunter]

Thanks folks. Good info re the aeroheating. Rocketman was our 1st choice. Currently absent.

+1 on Rocketman Parachutes... here are two links. Look them over then call and talk to Buddy. He checks in here once and a while.

Kevlar parachutes:
https://the-rocketman.com/kevlar/
Mach II Balistic parachutes:
https://the-rocketman.com/ballistic-parachutes/

@Buddy Michaelson can you help...?

Buddy has gone silent.

 

[Keisling]

Buddy makes great chutes... when he decides to finally make them.

 

[sriegel]

You might contact Valkyrie Recovery Systems https://www.valkyrierecoverysystems.com/

Ben had done some pretty wild recovery systems for research customers. I would trust his construction any day.

 

[jwhunter]

Ben at Valkyrie is helping us out.

Thanks.

John Hunter