The key to high-energy stages was to use liquid hydrogen as the fuel. Liquid hydrogen fuel appealed to rocket designers because of its high specific impulse, which is a basic measure of rocket performance. Specific Impulse is the impulse delivered per unit of propellant consumed. You might think of it as the efficiency of the rocket. Compared to an RP-1 (kerosene) fueled engine of similar size, liquid hydrogen fuel could increase the specific impulse or efficiency of an engine by 40 percent. The combination of hydrogen and oxygen for propellants made the moon shot feasible.
At various stages of lunar module design, mockup reviews were conducted to demonstrate progress and identify weaknesses. These inspections were formal occasions, with a board composed of NASA and contractor officials and presided over by a chairman from the Apollo office in Houston.
The Lunar Lander originally had two docking hatches, one at the top center of the cabin and another in the forward position, or nose, of the vehicle, with a tunnel in each location to permit astronauts to crawl from one pressurized vehicle to the other…
Since the lunar module would fly only in space (earth orbit and lunar vicinity), the designers could ignore the aerodynamic streamlining demanded by earth’s atmosphere and build the first true manned spacecraft, designed solely for operating in the spatial vacuum.
Max Faget’s position was that considering the difficulty of the job, if each mission was successful half the time, it would be well worth the effort. But Gilruth thought that was too low. He want a 90% mission success ratio and a 99% ratio for Astronaut safety. Walt Williams who was currently running the Mercury program believed that astronaut safety needed to be limited to only 1 failure in a million which was 99.9999%.
…From the information they gathered on the existing technical problems, Disher and Tischler concluded that prospects were only one in ten that Apollo would land on the moon before the end of the decade….
“The contractor role in Houston was not very firm. Frankly, they didn’t want us. There were two things against us down there. Number one, it was a Headquarters contract, and it was decreed that the Space Centers shall use GE for certain things; and number two they considered us (meaning GE) to be Headquarters spies.” Edward S. Miller of General Electric.
During 1962, NASA faced three major tasks: first the mode selection and its defense (covered in episodes 106-109), second keeping North American moving on the command and service modules (covered in episode 110) and third finding a contractor to develop the separate landing vehicle required by that approach. Which we will cover today in episode 111.