Parachute Launcher

[saltfever]

I am looking into the pneumatic chute launcher by Stroud. It operates on 150 psi air pressure but there is no mechanical backup in case you lose air pressure. It is a single point failure with no redundancy. Has anybody, using the Stroud system, come up with a mechanical (or other) backup plan?

[F104A]

We use a launcher but also a pilot chute. We've had a launcher failure and the pilot chute still pulled
the chute (bag) out of the can. I can give you a hint about our launcher if you want the info. Send a
personal message.

[Speed Limit 1000]

The Amo Steele Streamliner has air launched chutes with a third chute with a spring and pilot for a backup.

[Cajun Kid]

I am not convinced I would want an air launcher unless I had a mechanical back up or pilot too.

Just as I don't use power brakes, I use mechanical brakes with redundent master cylinders.

My Stroud LSR Chute works GREAT (no launcher, but hey my max speed in the Stude is calculated at 225 with E motor)  If I put the big motor in after SW 2011 , you can bet I add another Chute.

Charles

[saltfever]

I don't have the Stroud launcher so I don't know its mechanical design. I was thinking of adding a latched, conventional-chute-spring into the package. But don't know the design or feasibility. I am not required to have a second chute and was trying to avoid going that route in order to get redundancy.

[Joe Timney]

It still has a spring pilot chute so there will be deployment...just not as fast.

[saltfever]

Joe: The air-launch system has no spring and pilot chute. That is why I started this thread.
              http://www.stroudsafety.com/DragChutes.html

[hotrod]

How about set up a mechanical push rod activated by a pull cable to serve as a mechanical backup for the air launch piston.

If you can provide enough push so that the chute "falls out" of the launch tube it would open just slower than the way it was intended.

It seems like there would be some way to mechanically push or pull the chute bundle out of the launcher if the air system fails.


The other option would be to put a fitting in the back of the air launch that would pressurize the launch tube independent of the pusher piston. This would depend on the air supply part of the system still being functional but would be an alternative to get the chute out into the air stream.

Larry

[saltfever]

Larry: Stroud told me the cylinder is pressurized to 150 psi. The cylinder looks to be about an inch or so in diameter so I assume there is about 150 lbs of force pushing out the chute. I don't know if the high pressure is used for speed or there is that much resistance in the chute tube. The push-rod deal might not work well if there is that much resistance. Maybe pack a couple of valve (or die) springs in there someway might do it though. I like your idea of a backup redundant air supply.

[SPARKY]

He also has a new spring system that launches pilot only that we are using it has a air release that can be backed by mech---that is what we are going to.

[saltfever]

Thanks, Sparky. I didn't know that.

[panic]

...

[Glen]

The Vesco #444 liner uses a air blow out for the pilot. It shoots it out about 40 feet and in turn pulls out the main canopy. Both the low and high speed chutes employ this system. The system has a manual over ride as well.

[saltfever]

Panic: I was thinking of plumbing in two systems. Another supply cylinder with its own line tapped right into the deployment cylinder. IOW, the deployment cylinder would have two air lines. Each line would have its own on/off valve. Driver would only actuate one valve. The other would be the backup. But I don't like the idea of a single deployment cylinder.

Glen: any chance they might be kind enough to allow a picture of the mechanical mechanism the next time you are over there?

[Joe Timney]

That is weird...the one I have does have a spring...have to ask Bob.