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cwbullet

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Thanks. I am not making a profit off of this. This is for you so the more you, as a group, help, the better the site will be.
 

jqavins

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Thanks. I am not making a profit off of this. This is for you so the more you, as a group, help, the better the site will be.
Understood. I didn't mean to imply that I thought you were (and don't know what I wrote that may have seemed that way) but sorry if I offered any offense.

Crosswind velocity mph*(5280 ft/mi)*(1 hr/3600s) = Crosswind velocity FPS
Incidentally, conversion for mph to fps is exactly 22/15.
 

Andrew_ASC

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Thanks. I am not making a profit off of this. This is for you so the more you, as a group, help, the better the site will be.
If you need donations for site maintenances or server costs let us know.
 

jqavins

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OK, I don't know the physics in detail for vent hole sizing, but give me a chance. For given tube dimensions, one would expect there to be approximately the same total hole area even as the number of holes changes. If this is wrong, stop reading.

If that is right, then the calculator is defective. Look at the two screen shots below. the only thing I've changed is the number of holes:
upload_2019-6-11_13-18-2.png
upload_2019-6-11_13-18-46.png

With two holes you're indicating each is 1/2 the diameter that's needed with only one. But a hole of half the diameter has only 1/4 the area, so you've dropped the total area by half.

I agree with the prior posts that the output format is weird, though that is a distant second to making sure it's right.
 

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I will work on it tonight. I had it working but I must not have saved the formula.
 

cwbullet

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my calculation was slight off on the vent holes. I used the standard 0.25 per 100 cubic inches and my fancy calculation created an error. Thanks for catching it.
 

BABAR

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So a body tube reference?
Yes. This may not fit with your title, but I am presuming your site is meant to be rocket building information reference source, and above may be useful.
 

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I am going to have to make a to-do list.
 

DAllen

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WOW

What a fantastic idea. Thanks for putting the work into this. Well executed so far good sir.
 

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You cannot see it, but I am making a list of body tubes as a reference and will have it up in a week or so.
 

jqavins

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If you want to go all out, you could integrate the body tube database with the scale calculator to either let the user pick a tube for the new diameter, or recommend the nearest tube to the computed diameter. But I realize that's asking, perhaps, more than you meant to bite off, as with my other scale calculator suggestions. (I, myself, would just use a spreadsheet.)
 

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I have been meaning to put together a Body Tube reference for probably 25 years. Thank you so much for taking this on, it will be very handy. :)
 

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Anyone have any new ideas of calculators to add to a rocketry calculator?
 

neil_w

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Parachute descent speed calculator for flat parachutes (parasheets?)

Enter weight and target descent speed, give parachute size
Enter weight and parachute size, give descent speed
 

Mike Haberer

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Good afternoon,

I am working on a site:

https://rocketrycalculator.com/

Visit and if you have a calculator to suggest, send me a PM with a formula and I will research it.

Chuck
Hi, Chuck. I have a list of saved web sites with a lot of different rocketry related calculators. If you want them as a reference point for a (fairly) comprehensive list of calculators that are out there in the ether, let me know.
 

cwbullet

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Hi, Chuck. I have a list of saved web sites with a lot of different rocketry related calculators. If you want them as a reference point for a (fairly) comprehensive list of calculators that are out there in the ether, let me know.
Yes, please.
 

Mike Haberer

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teepot

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Parachute descent speed calculator for flat parachutes (parasheets?)

Enter weight and target descent speed, give parachute size
Enter weight and parachute size, give descent speed
Look for "parachute size calculator. It does exactly what your looking for. Besides flat chutes you can pick hemispherical and x form.
 
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