Canadian cooperation
Canadian engineers and other experts helped Apollo 11 make
the irst human landing on the Moon in July 1969, just nine
months before the Apollo 13 explosion. Yet most left NASA
by the time of Apollo 13. Canadian light surgeon Dr. William
Carpentier, who helped recover the Apollo 11 astronauts
after splashdown, was one of the few still working in mission
control in Houston when Apollo 13’s oxygen tank blew.“hey had to have some guidance on what happened when
the carbon dioxide level hit a certain point,” Carpentier
recalled. “And they needed some kind of timeline on the
problems that had to be solved. I was there, kind of on the
periphery, giving advice when I could give it.”He added there was little he could do while the astronauts
endured long hours of cold and dampness in a powered-
down spacecraft, headed to a re-entry scheduled the
morning of April 17.In the afternoon of April 16, with less than 24 hours to go
before splashdown, an engineer from Grumman Aerospace —
which built the lunar module — put in a call to the University
of Toronto Institute of Aerospace Studies.Barry French was pulled out of a staf meeting to take the call,
and soon he and a team that included engineering professors
Ben Etkin, Irvine Glass, Philip Sullivan, Roderick Tennyson
and Peter Hughes went to work on answering the question
that came from Grumman.crucial
calculations
Odyssey was supposed to cast of Aquarius the next morning,
April 17, near Earth. Usually the astronauts would leave the
lunar module stages behind at the Moon. But approaching
Earth, the module would have to be pushed farther away
than normal to make sure there was no collision with
Odyssey during re-entry.In a normal separation, the air was removed from the
tunnel that connected the two modules, and a set of
explosive charges physically separated the ring holding
the two craft together, pushing them apart.To separate the craft farther in this unusual situation, NASA
proposed to leave some oxygen in the tunnel, which would
give the two spacecraft an extra push. U of T’s experts were
asked whether leaving some air in the tunnel would be safe
given the pyrotechnics used in the separation, and whether
the air would help push the lunar module out of harm’s way.“We did some rough calculations,” Etkin recalled.he air pressure in the spacecraft was 258 millimeters of
mercury — or 34,400 Pascals — a third of the air pressure
at sea level on Earth. Etkin said the U of T group concluded
that air at about half of the spacecraft’s normal air pressure
setting was the right pressure for the tunnel. hey phoned
their conclusion back to Grumman.Apollo 13 space
vehicle coniguration
(NASA)SKYNEWS • MAR/APR 2020