Whenever he thought about it, he felt terrible. And so, at last, he came to a fateful decision. He decided not to think about it. ~John-Roger and Peter McWilliams
Question #33753 posted on 03/02/2007 3:01 a.m.
Q:

Dear 100 Hour Board,

How light (in oz.) should a 28" long model of the SR-71 drone be in order to fly well?

- RC modeler

A: Dear flying hansel,

Well if it's a scale model, let's see... 80,000 pounds at 107.4 feet makes about 62 lbs/in, which means your plane should weigh about 1,738 lbs.

What do you mean that's too heavy? Even at scale those turbojets should have 1,412 lbs of thrust! OK, fine. There's a site that shows a 60 inch model that flies well and weighs 39 oz. So you'd probably want your model to be about 16-18 oz. Turns out that's about 1 pound. I should have just guessed that and saved some time.

Now let me ask you a question. Why are you making a puny 28" model when you could be making one like this?

-=Optimus Prime=-