FAA scrutiny of on-demand Part 135 charter operators may increase following a report issued July 13 by the Department of Transportation’s Office of Inspector General (IG). This report is the first of two parts and focused on evaluating “the differences between FAA regulation and oversight for on-demand operators and larger, commercial air carriers.”

The IG audit tried to compare two different types of commercial aircraft operations and concluded that on-demand Part 135 charter operations receive far less FAA oversight and are subject to less stringent regulations than Part 121 airline operations. This audit suggests that if Part 135 on-demand and 121 regulations were similar, some notable accidents might not have occurred. According to National Air Transportation Association president Jim Coyne, “The IG largely conducts an apples-and-oranges comparison. Part 121 is very homogenous…. Part 135 contains every possible mission profile and includes single-engine pistons up to large-cabin jets. Of course the requirements are going to be different.”

While the IG audit notes that “the number of fatalities from on- demand operations makes it imperative that FAA take action to address these issues,” the report never compares the number of fatalities in Part 135 operations to those in Part 121. It cites a chart showing fatal accident rates for on-demand Part 135 operators versus Part 121 carriers from 2000 through 2008, and the Part 135 rate is far higher than the Part 121 rate. However, this chart uses estimated Part 135 accident rates based on FAA activity surveys while 121 flight hours are reported by airlines. The U.S. Government Accountability Office noted this discrepancy and concluded that it “could not calculate accident rates based on operations or miles traveled for small carriers because the FAA does not collect the necessary data.”

The IG audit suggests that homo- genizing Parts 135 and 121 would improve safety and that regulatory differences and lack of FAA oversight are at the root of some Part 135 accidents. A glaring omission in the IG audit is any statistical analysis to support that conclusion. For example, the audit notes four areas where the FAA has not implemented NTSB and industry recom- mendations to strengthen Part 135 safety: flight duty and rest; icing conditions; crew resource management; and cabin safety. There are no statistics to support the audit’s claim that these areas are causing a higher number of accidents among Part 135 operators.

There is also no comprehensive analysis of existing FAA oversight. The report cites an Alaska charter operator that flies tourists to glaciers with 17 ski-equipped aircraft, inspected eight times by the FAA during 2008. A Part 121 operator with 10 aircraft was inspected 199 times in the same year. The report doesn’t note that during 2008, the Part 121 operator likely flew tens of thousands of hours versus a few thousand by the Part 135 operator during its short summer season.

The audit’s conclusion that the “FAA does not effectively target inspections to higher-risk on-demand operators” might make more sense were it to include detailed analysis and a better understanding of the differences between Part 135 and 121 operations. The IG audit, concluded the Regional Air Cargo Carriers Association, does not place “enough emphasis on the inherently more risky [Part] 135 environment. Much of the flying is done in foul weather, on demanding schedules, in relatively unsophisticated aircraft, with a single pilot.”