Narrative:

While pre-flighting our aircraft I noted the bus voltages fluctuating from approximately 23-27 volts while on the gpu. With no ground personnel in sight I exited the aircraft to check the gpu. The fuel gauge was reading empty and the voltage output was fluctuating. I notified the ramp personnel in the baggage area and they promptly took action. The ramp personnel pulled another gpu over and hooked it up to the aircraft. During the gpu switch; I turned on the aircraft batteries to maintain system integrity. The second gpu immediately began spiking the voltage; so I notified the ground crew we would have to attempt a battery start. I told them to quickly disconnect the external power and air; which they did over the course of eight minutes. There were only two ramp personnel working our flight and they juggled our problem and loaded cargo the best they could. At this time the cabin became exceedingly hot; and the battery voltage was at 21.7 volts. I started the number 2 engine successfully in accordance with the aom; but was very close to having a hot start (915 degrees for 3 seconds); and did receive a bus fault after starter cut-off. This caused the cabin lights to go out; emergency lights to go on; and the aircraft to pressurize slightly more than usual; which was very uncomfortable for the already hot passengers and crewmembers. After realizing the situation and resetting the bus fault we were able to successfully start the number 1 engine. Prior to pushback with both engines running; the first officer and I made sure only the appropriate annunciators were illuminated and that all systems were up and running correctly. While the flight managed to depart on-time; I feel that yet again our ground support facilities have failed us. My flight attendant had to deal with a full cabin of hot and unhappy passengers because of poor equipment. On top of the obvious service deficiencies; I feel that we had a very real safety threat. First; our aircraft need those air carts in the summer; and the carts need to work. Secondly; the gpu's need to be reliable. Our first gpu was fine this evening; but I find it unacceptable that it ran out of gas! Because of this situation we came very close to having a maintenance delay due to 1) a hot start; 2) frying the electrical system; 3) over-pressurizing the aircraft; or 4) having a fire!!! Any of the problems tonight during engine start could easily have escalated into an aircraft fire at the gate. In conclusion; I respectfully make the following recommendations: 1) include an emergency/abnormal checklist for the dc bus annunciator for when the aircraft is on the ground during engine starts. 2) better quality control/assurance with our ground equipment.

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Original NASA ASRS Text

Title: A DHC-8-200 Captain related numerous shortcomings of ground support equipment and procedures while his aircraft was in service at the gate.

Narrative: While pre-flighting our aircraft I noted the bus voltages fluctuating from approximately 23-27 volts while on the GPU. With no ground personnel in sight I exited the aircraft to check the GPU. The fuel gauge was reading empty and the voltage output was fluctuating. I notified the ramp personnel in the baggage area and they promptly took action. The ramp personnel pulled another GPU over and hooked it up to the aircraft. During the GPU switch; I turned on the aircraft batteries to maintain system integrity. The second GPU immediately began spiking the voltage; so I notified the ground crew we would have to attempt a battery start. I told them to quickly disconnect the external power and air; which they did over the course of eight minutes. There were only two ramp personnel working our flight and they juggled our problem and loaded cargo the best they could. At this time the cabin became exceedingly hot; and the battery voltage was at 21.7 volts. I started the number 2 engine successfully in accordance with the AOM; but was very close to having a hot start (915 degrees for 3 seconds); and did receive a BUS FAULT after starter cut-off. This caused the cabin lights to go out; emergency lights to go on; and the aircraft to pressurize slightly more than usual; which was very uncomfortable for the already hot passengers and crewmembers. After realizing the situation and resetting the BUS FAULT we were able to successfully start the number 1 engine. Prior to pushback with both engines running; the First Officer and I made sure only the appropriate annunciators were illuminated and that all systems were up and running correctly. While the flight managed to depart on-time; I feel that yet again our ground support facilities have failed us. My flight attendant had to deal with a full cabin of hot and unhappy passengers because of poor equipment. On top of the obvious service deficiencies; I feel that we had a very real safety threat. First; our aircraft NEED those air carts in the summer; and the carts NEED to work. Secondly; the GPU's need to be reliable. Our first GPU was fine this evening; but I find it unacceptable that it ran out of gas! Because of this situation we came very close to having a maintenance delay due to 1) a hot start; 2) frying the electrical system; 3) over-pressurizing the aircraft; or 4) HAVING A FIRE!!! Any of the problems tonight during engine start could easily have escalated into an aircraft fire at the gate. In conclusion; I respectfully make the following recommendations: 1) Include an emergency/abnormal checklist for the DC BUS annunciator for when the aircraft is on the ground during engine starts. 2) Better quality control/assurance with our ground equipment.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.