sci-tech and cinema

Class this week has been focused on HVAC systems.  Boring stuff, I’ll admit, but enlivened today by one student’s question.

“Could someone really escape from prison by crawling through the ducts?”

I don’t know if the makers of Escape From Alcatraz had any actual HVAC consultants or not, but this is a legit question.  If you were designing a prison, wouldn’t you be careful not to have your mechanical engineer design, say, six-foot tall ductwork?  This seems like a fairly obvious rule of thumb, but it does have consequences.  You’d probably need a distributed mechanical plant to keep from having large ducting trunks, for instance.

We spun that out for a while, and then another student pointed out that the giant fans that crop up in any good prison escape movie also struck him as odd.  We did a bit of quick figuring and agreed that the back pressure from any fan mounted in the middle of a duct run (six feet tall or not) would be, at best, counter-productive.

It ended up being a fairly entertaining class session.  And I’ll make this offer to any Hollywood producers out there who are losing sleep over whether their next prison escape movie is realistic or not.  For a very reasonable cut of the box office (and, say, a week or two on a Malibu beach), my class and I will gladly review your script and redline it for plausibility.  We think the world would be a better–or, at least, better educated–place.