🚀 go-pugleaf

In article <1992Dec11.162931.1@vf.jsc.nasa.gov> oliver@vf.jsc.nasa.gov (Pat
Oliver) writes:
>Jim provided a good overview of the orbiter cooling.  My comments expand on
>what he said.

Ken:
And my comments expand on what Pat said.  (We could go on like this for
months.)

Jim:
>In article <1992Dec10.233907.4549@titan.ksc.nasa.gov>, 
>dumoulin@titan.ksc.nasa.gov (Jim Dumoulin) writes:
>>   When the payload bay doors are opened, radiator panels attached to
>>   the doors radiate heat.  If this is insufficent during orbiter
>>   operations, the flash evaporator subsystem is automatically activated.

Pat:
>The radiators consist of four panels mounted on each of the payload bay
>doors.  The forward two panels on each door can be deployed to provide
>four additional cooling surfaces.  Very few missions have flown hot
>enough attitudes to require the deployment of the radiators.

Ken:
We don't like to deploy the radiator panels.  In their deployed
position, they don't really give that much more radiative cooling
capability than leaving them stowed flush against the payload bay doors
(PLBD's), and if they stick open, the PLBD's won't close properly,
causing what's known in MCC as "a bad day."  After this happened often
enough in simulations (sims), we wrote some flight rules which
discourage the use of deployed radiator panels, as opposed to stowed
radiator panels.

Since this wasn't known early on in the Program, you'll still see
"artist's conceptions" of the Orbiter from the '70's and '80's with
the radiator panels deployed.  By now, even the artists have 
figured out that we don't actually deploy these things any more.

-- Ken Jenks, NASA/JSC/GM2, Space Shuttle Program Office
      kjenks@gothamcity.jsc.nasa.gov  (713) 483-4368

     "...Development of the space station is as inevitable as 
      the rising of the sun." -- Wernher von Braun