Aihnss.177
net.columbia
utzoo!decvax!ucbvax!ihnss!karn
Wed Nov  4 17:41:53 1981
APU filters clogged
The problem with the APU's on Columbia is apparently due to clogged
filters that weren't replaced after the first flight.  This is what
caused the lubricant overpressure on 2 of the 3 APU's that caused
the scrubbing of the launch today.

A NASA spokesman said that the launch would have succeeded even with
the overpressure problem, but they wanted to have the maximum margin
of safety for landing, when the APU's are again needed to drive
aerodynamic surfaces.

I'd certainly prefer waiting a couple of days over having a launch
failure, anytime.