Properties of a Pocket Calculator for Astronauts

[Thomas Okken]

(09-06-2019 11:26 PM)Gene222 Wrote:  

(09-06-2019 11:53 AM)pinkman Wrote:  What about this information ?

Nice photos of the HP-41C with a keyboard overlay. Too bad the photos don't show what module was used or what programs were used, as requested by the OP.

This was covered in HP Key Notes V5N1.

Quote:Two calculators were set up for the flight. Each HP·41C was outfitted with four Memory Modules, giving each the memory to handle more than 2000 program lines. The flight suit pouches for the calculators also held extra Memory Modules, extra batteries, and a card reader and magnetic cards containing the programs, just in case they had to be reloaded in flight.

For the first shuttle flight, one Hp·41C was dedicated to the Center of Gravity program, and one to the Acquisition of
tI Signal program. These programs were loaded into the calculators shortly before launch. The Center of Gravity program was used before reentry into the earth's atmo- sphere to compute the shuttle's present center of gravity and the amount of fuel to be burned in each tank to reach the required center of gravity for reentry. This center of gravity program was termed "flight critical" by NASA and necessitated extensive pre-launch testing of the calculators.

The other program, the Acquisition of Signal program, ran continually in the second calculator, starting at launch, so it could display at any time the next ground station that Columbia could contact, when it would be in contact, the duration of that contact, and which frequency (UHF or S- band) could be used. And, thanks to Continuous Memory, the calculator did not have to be on during the whole flight.