A B737-300's left generator CSD low oil pressure light illuminated in flight with the APU generator on MEL. The CSD was disconnected; an emergency was declared and the flight continued to the planned destination.
Synopsis
A B737-300's left generator CSD low oil pressure light illuminated in flight with the APU generator on MEL. The CSD was disconnected; an emergency was declared and the flight continued to the planned destination.
Narrative
The flight departed approximately thirty minutes late due to deferring the APU generator (still could use air). We'd been at FL360 for approximately thirty minutes when the oil low pressure light on the number one engine generator CSD came on. I was the pilot flying and the Captain was the pilot not flying. The Captain got the QRH; read the procedure for CSD low oil pressure; and proceeded to disconnect the number one engine generator. Since the APU generator was deferred; we were down to one generator. Load shedding of non-essential electric items ensued; including one left fuel pump; right electric hydraulic pump; the Captain's forward window heat; the First Officer's side window heat and several cabin items including galleys; lavatories; and some lights. The weather going at our destination was IMC with rain and icing in the descent. We followed the QRH procedures for CSD and the QRH procedures were followed for the remaining caution items related to the generator disconnect. All follow-on procedures were complied with. Regarding the fuel pump low pressure; we began a precautionary descent from FL360 in an effort to avoid fuel starvation to the number one engine. This was not in accordance with the QRH. (The QRH directs the descent if both fuel pumps are inoperable.) Since the workload was relatively high (short time of flight remaining; communication with Dispatch; QRH procedures; crew/passenger briefing; and landing tasks); we felt this to be a prudent call. Read and follow the QRH procedure to the letter. Get better rest the night before. I (the First Officer) had a poor night's rest; and had gotten up very early to drive in to start the trip; and therefore was not at the top of my game. I felt the Captain was much more on top of things than I was.
Second reporter narrative
The First Officer was flying the airplane and I broke out the QRH and followed the procedures with the main step being to disconnect the CSD before further damage could occur. This was done as were all procedures as per the QRH. Since we were down to a single generator; and with multiple caution lights; an emergency was declared with the Center; and we began our descent into our destination. I incorrectly read the Left Forward Fuel Pump Low Pressure Checklist note 3 which states; 'Engine flameout may occur above 30;000 FT due to fuel starvation.' I should have read note 2 which concerns MEL 28 dispatching requirements. We initiated an early descent due to my concern about losing an engine up at cruise altitude. Dispatch was notified through ACARS of our situation; and we informed them that we would be continuing to our planned destination to land. Our departure airport had gone down to CAT III weather shortly after we departed. A nearby airport was also checked as another possible 'best suitable' airfield; but they were reporting rain. We made the decision to continue on to the planned destination as they were not reporting any rain (at the time) and ceilings were better than 1000/3. The flight attendants were informed [of] what had happened; that we had declared an emergency; and that they could expect normal landing/rollout procedures. Then a PA was given to the passengers advising them of what had happened; that the airplane was flying just fine; and that although they would see fire/crash crews on our landing rollout and taxi to the gate that it was a precaution only. During our descent; the QRH checklists were run for all additional caution lights (low fuel pump pressure; low 'B' electric hydraulic pump pressure; window overheat). All other systems continued to operate normally. Dispatch was brought up on the number two radio and we discussed verbally what our plan of action was (direct the airport; ILS; flaps 30; normal landing rollout and taxi in) and to see if there was anything else that might be slipping through the cracks. We also asked the Chief Pilot on call to weigh in on any recommendations he/she might have. Both Dispatch and the Chief Pilot on call concurred with our intentions. I decided to let the First Officer continue to fly the airplane; since it was handling normally and it allowed me to remain in 'center field' and manage the situation. Also; my forward window had iced up (light rime icing was reported by ATC in the descent); and he still had a clear forward window. My window cleared once we got below the freezing level (around 4;000 FT); we flew a normal procedures ILS to 10R; and we broke out around 1;500 FT. We landed normally and taxied to the gate without further incident. Although we were working hard to handle the situation; going a little slower with the QRH might have allowed me to read the correct note on the left side of the QRH; and not descended when I didn't need to.
More incidents for this aircraft family →
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.