by Kristin Winter » Tue Aug 05, 2014 6:26 pm
I am not sure. I have a manual for the IIIB-1 around here someplace. I think it is that they removed the airspeed control features of the IIIB because they were problematic. Ultimately, they scrapped the whole pre-select thing and went with an altitude hold mode for the Altimatic IIIC/Century III, but that was too late for the Comanches, except by STC. I recently used the STC to convert my Altimatic IIIB to a Century III in my PA-30.
Kristin