[net.columbia] Abort to Orbit

alb@alice.UUCP (Adam L. Buchsbaum) (07/30/85)

Six minutes into its flight, Challenger lost power in its
centre main engine, and the other two engines burned 1
minute 32 seconds longer to compensate.  The crew was
instructed to abort to orbit, bypassing a possible emergency
landing in Rota, Spain.  The shuttle ended up in an
orbit ranging between 120 and 160 miles, lower than
the hoped for 240 mile circular orbit.  An OMS burn
33 minutes into flight is to circularlize the orbit.
NASA hopes that the mission can be completed to its
full seven day duration, but no decision has been
made yet.

mike@amdcad.UUCP (Mike Parker) (08/01/85)

I seem to remember that the range of the 747-shuttle piggyback
combination is only about 1000 miles. If they ever do abort to
Rota, Spain how do they get the damned thing back to the USA

Mike

jcjeff@ihlpg.UUCP (Richard Jeffreys) (08/01/85)

> I seem to remember that the range of the 747-shuttle piggyback
> combination is only about 1000 miles. If they ever do abort to
> Rota, Spain how do they get the damned thing back to the USA
> 
> Mike

Quite easy really. Refuel the 747 at a couple of airports on the way!

The 747 took Enteprise to the Paris (France) Air Show a couple of years ago.
The 'plane refuelled in Greenland and also at Fairford (England) USAF base,
where I, and many others, had the chance of a very close look at the shuttle.

The 747 stayed at Fairford for a couple of hours and went on to France. On
the way back it was flow back to Stansted (just outside London) and stayed a
couple of days, giving many people the chance to see the shuttle on it's
first trip outside the USA.

-- 
 [ I bought a ticket to the world, 
                              But now I've come back again - Spandau Ballet ]
------------------------------------------------------------------------------
||      From the keys of Richard Jeffreys ( British Citizen Overseas )      ||
||              employed by North American Philips Corporation              ||
||              @ AT&T Bell Laboratories, Naperville, Illinois              ||
------------------------------------------------------------------------------
||  General disclaimer about anything and everything that I may have typed  ||
------------------------------------------------------------------------------

markb@sdcrdcf.UUCP (Mark Biggar) (08/02/85)

In article <2243@amdcad.UUCP> mike@amdcad.UUCP (Mike Parker) writes:
>I seem to remember that the range of the 747-shuttle piggyback
>combination is only about 1000 miles. If they ever do abort to
>Rota, Spain how do they get the damned thing back to the USA

How about:
Spain -> England -> Norway -> Reykjavik, Iceland -> Labrador -> Home free
Any place you can land and take-off a C5 Galaxy military transport can
handle NASA 909 with shuttle.

or

Drag it to dock, use cargo hoists to put it on air-craft carrier, sail home.

or

Read "Shuttle Down" by Corry, where they have to get a shuttle back
from Easter Island.  Which they now have to plan for, as they have
just signed a treaty with Chile allowing the use of Easter Island as
an emergency landing sight for Vandenburd polar shuttle launches.
Boeing appearently has plans for mid-air fueling equiptment for 747s.

Mark Biggar
{allegra,burdvax,cbosgd,hplabs,ihnp4,akgua,sdcsvax}!sdcrdcf!markb

henry@utzoo.UUCP (Henry Spencer) (08/02/85)

NASA is looking at flight refuelling for the shuttle-carrier 747, in fact,
because there are some possible emergency landing sites which are not
within 747+shuttle range of another airport.  Aborting a polar-orbit launch
from Vandenberg, for example, you end up on one of a few small islands way
the hell out in the Pacific.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry

tc@amd.UUCP (Tom Crawford) (08/06/85)

Here are paragraphs from an article in Aug 5 Aviation Week.  These are
reproduced without permission.

Abort-to-Orbit Incident Will Intensify Shuttle Engine Procedure Reviews

Johnson Space Center-  The premature shutdown of one of the shuttle
orbiter Challenger's main engines that forced an abort to orbit last
week was caused by a temperature sensor failure in the Rocketdyne engine
rather that an actual problem with the propulsion system, shuttle managers
believe.

...

Lead ascent flight director Cleon Lacefield said a reexamination of data
indicates that, had the second engine failed at a time when abnormal
sensor readings were occurring in it, Challenger could still have 
achieved a safe but tenuous orbit.  A second engine failure, however, would
have caused the shuttle's 39-ton Martin Marietta external tank to fall on
populated areas of Europe somewhere along a line stretching across central
France, Switzerland, south of Milan or near Athens.
...
<There is a fairly long "time sequence of events" which I omit>

5 min. 55 sec.  Fullerton, piloting Challenger, rotated a switch on the 
instrument panel to the abort ATO position, then pushed an ajoining
abort command button.  This told the orbiter's computers that ATO
procedures were now required.  It immediately ignited Challenger's
two Aerojet orbital maneuvering engines to dump 4,400 lbs. of OMS
propellant so the remaining main engine thrust could be used more
efficiently.

6 min - For 106 sec. Challenger's two OMS engines fired along with the
two remaining main engines.  The OMS engines provided an additional
12,000 lb. of thrust, but this was incidental to the abort situation.
The requirement was to dump OMS propellant to lighten the load.

......

8 min. 12 sec.  Howard at the booster console saw sensors on the right
main engine, one of two still firing, start to act improperly.  She
first saw the B-side fuel pump temperature sensor fail on the right
engine, the same failure that started the center engine's problems....

8 min 45 sec  Lacefield had Richards radio Challenger, "Main engine
limits to inhibit," an emergency call to prevent the second engine
from failing if the temperature sensor data climbed higher.  Fullerton
immediately flipped a switch on the console, canceling out the
protective circuitry in the engines that could have shut down the
engines.

<Sound pretty exciting to me>

			Tom Crawford
			...amd!tc