[KC Jones]

the norden sight used elevation to find the target and begin automation, and is the only user of elevation... so I don't see your point.

That aside, I've been thinking of making a slide rule to find TAS from IAS, as was done in real life

edit: tater, you posted the same time as me http://en.wikipedia.org/wiki/E6B

You could use the dual needle airspeed indicator that is in the bombardier's compartment for the Norden.

The following is just a test shot of the TAS speedbar option of the BombBayDoors mod along with the ASI in the bombardier's compartment (I was going very slow)



Or you could just buy an E6B that already has a lot of conversion features on it including IAS-TAS (a must-have for serious pilots).



I was lucky enough to find this old WWII RAF one at a militaria show.