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Space Calc
Doing the math, so you don't have to.

Ship Decompression


If you get a hole in your spacecraft, the air that's presumably inside it will of course start rushing out. This calculator will (roughly) calculate how fast this happens, as well as the effect on any free-floating objects.



Decompressing room's volume: Assume effectively infinite.
Decompressing room's cross-sectional area: (from circle diameter: )
Hole's cross-sectional area: (from circle diameter: )


With Object
Object mass:
Object cross-sectional area:
Object coefficient of drag:


Technical Notes

I derived the equations that describe all this and presented my results on Google+ (results, derivation). The main point is that this is an approximation based on the drag equation. This is a good approximation, mind (just about as good as you can get without running and interpreting a fluid simulator), but it's still an approximation.

Also presented was a Python script (here) that implemented the analysis given. This JavaScript version is based on it.

For an overview of real-life incidents and an approximation, see here. If someone can get me a copy of the cited 1953/1954 paper, I'll see if it's better than what I came up with:

Demetriades, S. T. "On the Decompression of a Punctured Pressurized Cabin in Vacuum Flight." Jet Propulsion 24.1 (1954): 35-36.