EMS Helicopter Fuel Exhaustion

By Richard N. Aarons
Source: Business & Commercial Aviation

Fatigue

The pilot had been off duty for five days before the accident — most of that time at home in Lincoln, Neb. The day before the accident, the pilot checked into the layover hotel in St. Joseph about 1423 and attended a company ground training session at 1630. The pilot's wife spoke with him later that evening and he had “sounded good.” A coworker (an Air Methods communication specialist) also spoke with the pilot by telephone that evening and reported that the pilot stated his training went well. He used his cell phone at about 1123 and again at 0019 on the morning of the accident.

On Aug. 26, the day of the accident, the pilot arrived for his shift sometime before 0630. He spent 20 min. discussing operations with the departing night-shift pilot who recalled later that the accident pilot seemed alert. Coworkers all described him as alert and functioning normally; however, the accident pilot told a coworker during a telephone call at 0830 that he did not sleep well in the hotel and felt tired.

According to cell phone records, the pilot made and received multiple personal calls and text messages throughout the day. The Safety Board correlated cell phone voice and texting records with the day's activities. During the period that the pilot was checking the reconfiguration of the accident aircraft, the pilot received multiple text messages and responded to some. Additional text messages were sent from the pilot's cell phone during time periods when the helicopter was in flight on the accident leg and the preceding leg and while the helicopter was on the Harrison County Community Hospital helipad.

Safety Board’s Analysis

The Safety Board believes the pilot missed three discrete opportunities to identify that the helicopter had inadequate fuel to complete the assigned mission — (1) during a required preflight inspection, (2) immediately before takeoff and (3) during the post-takeoff status report to AirCom. The electric fuel gauge was operating correctly and should have accurately displayed the helicopter's fuel state, about half of the normal 2-hr. fuel load, at these times.

It is unlikely, said the Safety Board, that the pilot deliberately misreported the fuel level because Jet-A fuel was available at the takeoff airport, and the pilot could have had fuel added without difficulty or penalty. It also seems unlikely that the pilot repeatedly misread the gauge indication, especially given the obvious difference in visual indication between the actual level (35%) and the reported level (70%).

Although the pilot had been advised during the shift change briefing that the helicopter was low on fuel, said the Safety Board, it is possible he forgot about this communication during the intervening 11 hr. before the first leg of the mission. If so, he might reasonably have expected the normal 70% level for an active helicopter.

“Such an expectation would be consistent with the incorrect fuel status report he provided after takeoff. Also, consistent with what the pilot subsequently stated, he had performed a preflight inspection on the earlier active helicopter (N101LN), and it was fueled to 70%.” Past Safety Board investigations have identified instances in which pilots made callouts without first verifying the cockpit indication that corresponded with the callout. Therefore, it is likely in this case that the pilot reported the fuel he expected to be in the helicopter without effectively referencing the fuel gauge.

The pilot's plan to proceed from Harrison to Liberty “was highly risky because of the limited fuel on board, said the Board. The plan did not meet 20-min. reserve fuel requirements for Part 135 operations. The difference between the actual fuel situation (30 min. or about 18%) and the fuel the pilot reported in his post-takeoff report (45 min. or about 26%) corresponded to a difference of about one marked increment on the fuel quantity gauge and should have been apparent to the pilot as he waited on the ground and considered his abnormal fuel situation. Further, the difference between the actual fuel situation and the minimum fuel required for the trip (52 min. based on the estimated time en route to GPH of 32 min.) was even greater. “Therefore, the pilot almost certainly knew that he did not have the required fuel reserve and misrepresented his fuel situation in his post-takeoff report because he wanted to give the appearance of compliance with the 20-min. fuel reserve requirement.”

The pilot undoubtedly knew that his decision to proceed with the mission was risky, and company personnel uniformly reported that the pilot could have aborted the mission at Harrison County Community Hospital without fear of serious negative consequences from the company, said the Safety Board. “This raises questions about the reasons for the pilot's decision to proceed. The pilot was new to the company and might have been concerned that aborting the mission as a result of an error during preflight preparation would negatively affect others' perceptions of his reliability as an employee. In addition, aborting the mission would likely have involved inconveniences (such as waiting at the hospital for fuel to be delivered) that the pilot probably preferred to avoid. Finally, he might have been influenced by time pressure associated with the urgency of the patient's medical condition and the implications of a delay in treatment.
“Although the pilot did not express such concerns during any recorded communication, such concerns have played [roles] in past safety-related incidents involving EMS flights. At the very least, the pilot would have expected that aborting the mission would result in some degree of discomfort for him and the patient. The NTSB concludes that the pilot departed on the second leg of the mission despite knowing that the helicopter had insufficient fuel reserves likely in order to avoid delays and other possible negative outcomes that could have resulted from aborting the mission.”


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