Author Topic: Parachute Sizing  (Read 1469 times)

Offline lake_harley

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Parachute Sizing
« on: May 08, 2022, 10:51:35 AM »
Just how bad would it be to use a parachute on a car about 2/3 the weight of the specs on a manufacture's sizing chart. The car would also be slower than the speeds listed for the heavier car chute as well.

The reason I ask is that I fully intend to put a chute on the FED I'm building, but at the races last night at my local 1/8 Mi track I never saw a single car deploy a chute and they were running much faster MPH and much quicker E.T.'s than what my car will be capable of. I read of "soft" and "hard" opening chutes, but I would think that any particular chute would open softer at 100 MPH than it would at 140 MPH or more.

I don't want to disregard a manufacturer's recommendations or safety. I was able to pick up a nice chute but was told it's for a heavier car and wouldn't be suitable for my FED. I can fully understand the danger of using too small a chute for the speed and weight of a car, but it seems a chute a bit too big to not be as critical, especially at slower speeds.

Thanks, in advance for advice from a user's standpoint.

Lynn

Offline wideopen231

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Re: Parachute Sizing
« Reply #1 on: May 12, 2022, 07:28:50 PM »
WIth weight of FED's being less than most cars and speeds you are talking about any chute will work. I am looking fo get rid of two big chutes I have and get smaller because don't need big ones and big weight savings at same time.
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Offline lake_harley

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  • Your Best Time: 7.06 @99.58 - 1/8 mi.
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  • Your Vehicle: 145" FED
  • General Location: SE Missouri
Re: Parachute Sizing
« Reply #2 on: May 13, 2022, 05:47:01 AM »
When I sent the chute to Stroud, they said it was a Model 430 Std. 32. I was told the correct size is a model 410. I got it back from them as-is, still set up to be "launched", rather than having a pilot chute. Is there a chance that the chute is so big that it wouldn't even "bloom" at my lower 100-ish MPH 1/8 Mi. speed? I had considered buying a pilot chute and chute pack to convert/complete the chute for pilot deployment.

I don't think I'll even have to use the chute where I plan to run the car, but if it was needed in an emergency I want it to work even if the deployment would be hard with the cars much lighter 1650-ish expected weight. I still have time before the car is completed but I hate the indecision about things like this clogging my brain.

Here's a link to Stroud's sizing chart. The chute I have is the one shaded in yellow in the left hand side chart. https://stroudsafety.com/racing-parachutes-and-launchers/#size

Lynn
« Last Edit: May 13, 2022, 05:51:40 AM by lake_harley »