kent@vf.jsc.nasa.gov (05/29/91)
In article <1991May28.122928.20347@cbnewsl.att.com>, sw@cbnewsl.att.com (Stuart Warmink) writes: >> WORK COMPLETED: >> - Installation of plugs instead of temperature transducers in the >> main propulsion system liquid hydrogen main engine inlets. Offi- >> cials determined that these transducers can be eliminated and >> still meet the launch commit criteria and flight rules. An >> analysis is continuing to determine if the liquid oxygen tempera- >> ture transducers can also be eliminated. > > This seems kind of strange. Either the sensors are needed or they are not. > If they are not, why scrub the mission when they are faulty? (OK, so this > time they were cracked) If they are needed - presumably to guard against > dangerously high temperatures - then why fly without them? The sensors are up stream of the main engine and were installed to determine if any gas was forming in the fuel or LOX lines. They have shown that no gas was forming so now they can be removed and replaced with plugs. Not all of the sensors are being removed. Most are being taken out. All of the ones that are downstream of the last filter screen before the turbine are being removed. > > A further analysis in continuing to determine if 4 of the 5 flight control > computers can also be eliminated :-) > MY OPINION FOLLOWS: Believe it or not the engineers on the shuttle program have sound solid arguments for what they do. It is not just arbitrary. As for not removing them earlier: Up until now, there was no reason to remove them. -- Mike Kent - Lockheed Engineering and Sciences Company at NASA JSC 2400 NASA Rd One, Houston, TX 77058 (713) 483-3791 KENT@vf.jsc.nasa.gov