The CM’s hatch was closed, the “boost cover” of the Saturn IB rocket was sealed and pure oxygen was steadily pumped into the cabin.Īs the afternoon wore on, niggling problems hindered the test. Roger Chaffee climbed aboard, taking the right-side pilot’s seat, and Ed White entered last, plopping into the center seat in his role as senior pilot. Grissom took the command pilot’s seat on the left side of the cabin and quickly became aware of a foul odor-like soured buttermilk-and technicians scrambled to the spacecraft to take air samples. He hated Block 1.Įngineers work aboard the Block 1 Apollo 1 Command Module (CM) during activities associated with installation of the spacecraft’s heat shield. After emerging from the test, Schirra took Grissom to one side. The previous evening, their backup crew- Wally Schirra, Donn Eisele and Walt Cunningham-had sat inside the CM for a “plugs-in” test, with Apollo entirely dependent upon electrical power from ground support equipment, and the hatch left open. (Morrow herself scornfully referred to Project Apollo as “Project Appalling.”) According to their secretary, Lola Morrow, all three men were unusually subdued and in no mood for the so-called “plugs-out” test. With a pessimistic air of foreboding, the astronauts crossed the gantry at Pad 34 early on the afternoon of 27 January 1967. As the hands of fate turned on Apollo 1, pure oxygen and an immovable hatch-coupled with a mysterious ignition source-would spell death for Grissom, White and Chaffee. Photo Credit: NASAīy adopting an inward-opening hatch, cabin pressure would keep it tightly sealed in flight, but difficult to open on the ground. North American wanted to build a single-piece hatch, fitted with explosive bolts, but NASA felt that this might increase the risk of it misfiring on the way to the Moon.Īpollo 1 astronauts (from left) Ed White, Virgil “Gus” Grissom and Roger Chaffee are pictured during water egress training in the Gulf of Mexico in October 1966. Other worries surrounded the Apollo CM’s hatch: a complex device which came in two cumbersome pieces: an inner section, which opened into the cabin, overlaid by an outer section. Of course, if there was a real emergency and you had to use the suit, you’d really have been in trouble.” “To walk on the Moon,” wrote Deke Slayton, then-head of the Flight Crew Operations Directorate (FCOD), in his autobiography, Deke, “you needed to get out of the spacecraft…and with a mixed-gas system you’d have to pre-breathe for hours, lowering the pressure and getting the nitrogen out of your system so you didn’t get the bends. The astronauts’ space suits complicated the issue yet further. Moreover, a mixture of this type avoided many other troubles associated with pure oxygen-eye irritation, hearing loss, and a clogging of the chest, for example-but the complexities of building such a system threatened to make it prohibitively heavy. NASA knew that a two-gas system, providing an Earth-like mixture of 80 percent nitrogen and 20 percent oxygen, pressurized to one bar, would reduce the risk of fire. The choice of pure oxygen had not been made lightly. The Block 1 Command Module (CM) was intensely distrusted by many astronauts on safety and reliability grounds. At an early stage, North American objected to the use of pure oxygen, but NASA, which employed it without incident during its Mercury and Gemini programs, ruled against it. This would eliminate the risk of the spacecraft imploding, but at such high pressures there remained a danger that anything which caught fire would burn explosively. In space, the cabin would be maintained at a pressure of about one-fifth of an atmosphere, but from ground tests would be pressurized to slightly more than one atmosphere. NASA had mandated that the Apollo Command Module (CM) should operate a pure oxygen atmosphere-an extreme fire hazard, admittedly, but far less complex than trying to implement a more Earth-like oxygen-nitrogen mix, which, if misjudged, could suffocate the men before they even knew about it. To be fair, North American had faced their own technical challenges. The launch of Orion’s Exploration Flight Test (EFT)-1 mission in December 2014, as seen through the Pad 34 site of the Apollo 1 fire.
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