If Space Plane Must Be Abandoned At ISS, Could It Land Without
Crew?
Should space shuttle astronauts have to abandon their landing
plans and hightail it to the International Space Station in an
emergency, what happens to the damaged or malfunctioning shuttle
itself? NASA is trying to address that issue, wondering with all
its bureaucratic might whether the shuttle might be remotely
piloted home.
It's not as far-fetched as it seems -- especially in these days
of routine UAV flight. Shuttle landings are, for the most part,
highly automated. Astronauts are required to lower the landing gear
and to deploy sensors that feed them data on altitude, airspeed and
temperature during the very last phase of flight.
"All of those things in a theoretical sense can be automated,
but they are not currently connected to the computer system," said
Wayne Hale, NASA's deputy director of the shuttle program. He was
quoted by the Orlando Sentinel. "When we designed the shuttle years
ago, they weren't (connected) for a variety of reasons. The
modifications to allow that capability to be automated are going to
take some time."
That would be a rather startling alternative to sending a
damaged shuttle into a remote part of some ocean where it could
break up without hurting anyone or anything on the ground.
"This is sort of a last-ditch effort to salvage the orbiter,"
Phil Engelauf, a mission operations manager at Johnson Space Center
told the Sentinel.
But the very damage that might force astronauts to abandon ship
might also make it a bit impractical to pull off such an automated
return to Earth.
"I am not at all sure how we would use that capability, because
here you've got an orbiter that is not safe to bring people back on
and yet you're going to try to land it, presumably in case you were
too conservative," said Hale. "But in doing that you have to fly it
over folks."
Oh, yeah.
But then, there's the
possibility that the crew might become incapacitated in-flight --
unable to make it to the ISS or land themselves.
So the question becomes, how do you automate the space plane to
land by remote?
"The least intrusive versions, which are the riskiest in
execution, you probably could have ready in maybe a year, maybe six
months," Hale told the Orlando paper. "The more intrusive things
would take several years to engineer."
The long-term fix would involve wiring all flight controls and
related functions to a central computer that would accept commands
from an Earth-bound pilot. The short term fix would be to design a
patch panel or a system of jumpers that astronauts could build that
would do the same job.
Can't be done? Not so. In 1981 and 1982, the shuttle's autopilot
capability was tested all the way down to 125 feet AGL. A full
landing -- with the flight crew operating only the landing gear and
those atmospheric probes -- was planned for 1992, but was canceled
and never undertaken again.
The Russians did it, though. Their one and only flight of the
Buran shuttle in 1988 orbited Earth twice, then landed within five
feet of the runway centerline in Kazakhstan. There was no one
aboard.