Newest Carrier Instrument : Trodi (Touchdown Rate of Descent Indicator) developed by North American Aviation's Electro-Mechanical Department, has been adopted by the U. S. Navy to determine quickly the Proper speed at which a plane must descend to make a safe landing. Trodi sends out two beams of light through which the approaching plane must pass, than records immediately data which formerly required several days to compute from photographic records. The new instrument (on pedestal upper left)