Internal Turbine Temp. At -40F none of the batteries were able to start the aircraft. Again, it can be seen that the performance of the VRLA's and NiCd are comparable. Starting tests - Results are the average of three successive trials. A second series of tests was then conducted with 1 VRLA battery and the NiCd battery.
Successive engine starts with no recharge, various temperatures.
The Federal Express aircraft were initially fitted with nickel-cadmium batteries. These batteries were selected to provide a low maintenance high reliability battery system for these aircraft. However, there were significant Ni-Cd battery problems in the field due to the manner in which the battey and aircraft are used. Initially the NiCd battery was to be removed from the airplane after 200 flight hours of operation and sent to Tennessee for deep cycling, capacity checks, and other maintenance activities on a scheduled basis. This included batteries from the Federal Express operations in Puerto Rico and the Philippine Islands.