March 6, 2014

Focusing on four factors common to helicopter accidents – weather, loss of control, controlled flight into terrain/obstacles and night operations – the FAA recently published a final rule establishing new operational, training and equipment requirements for FAR Part 91, 120 and 135 specialized medical operations. The new rules become effective on April 22.

Download the final rule: “Helicopter Air Ambulance, Commercial Helicopter, and Part 91 Helicopter Operations” (PDF)

The new requirements establish flight rules and enhance communication, training and on-board safety equipment requirements for helicopters. Air ambulance operations have come under increased public scrutiny from government officials, in the wake of 62 accidents and 125 fatalities between 1991 and 2010.

“The unique nature of emergency medical transportation is receiving greater attention from government officials,” says Peter Korns, an operations specialist with NBAA.

Although air ambulances fly “under unique conditions,” these helicopters are not the only ones that face challenges and land at unfamiliar sites with hazards such as trees, towers and wires, so the safety factors embodied in the new rules should be of interest to all rotary-wing operators.

New weather minimums for Class G airspace between the surface and 1,200 feet will affect all helicopter operations. To reduce the chances of inadvertent flight into instrument meteorological conditions (IMC), 14 CFR 91.155 adds visibility requirements – 0.5 statute miles during the day and 1 statute mile at night – to operating clear of clouds.

In their initial and recurrent training, all Part 135 helicopter pilots must demonstrate that they can maneuver and exit IMC when they inadvertently encounter it. This includes flat-light conditions and the helicopter-induced IMC of rotor-washed snow (whiteout) or dust (brownout), and rotorcraft pilots must be able to recognize and avoid these situations.

The rule sets new, higher weather minimums for Part 135 alternate airports named in flight plans: 200 feet above the minimum for the instrument approach procedure to be flown and one mile visibility, but never less than the approach’s minimum visibility.

All Part 135 helicopter operations will require more survival equipment when operating over water. After April 24, 2017, they must be equipped with an approved radar altimeter or device that incorporates one. There is a deviation process for aircraft unable to incorporate this equipment.

The requirements for air ambulance equipment, operations, and training are contained in Subpart L of Part 135. These requirements include a helicopter instrument rating for all air ambulance pilots, whose preflight planning must identify and document the highest obstacles along their planned routes and include a risk analysis that considers all aspects of the route and weather.

Operators with 10 or more air ambulances must establish an operations control center to help pilots with the weather and route information and risk analysis, as well as to provide flight monitoring. Because these operations control specialists perform safety functions like a dispatcher, they are subject to Part 120 drug and alcohol restrictions. In addition, by April 23, 2018, air ambulances must be equipped with a flight data monitoring system.

After April 24, 2017, air ambulances must be equipped with a helicopter terrain awareness and warning system (HTAWS). With the radar altimeter requirement, this equipment will improve pilot awareness during the helicopter’s unique operations, especially at unimproved landing zones, confined areas and other areas that require vertical approaches.

When operating in Class G airspace, air ambulances will have specific VFR ceiling and visibility minimums for day, night and night vision or HTAWS operations in local and non-local mountainous and non-mountainous locations.

The rule encourages IFR operations when the airport doesn’t have a published instrument approach or weather reporting. Air ambulances can land if the helicopters can descend from the minimum en route altitude in basic VFR conditions, and they can land at sites without weather reporting by drawing on the nearest approved weather information and flight planning a suitable alternate.

For more information, contact NBAA’s Peter Korns at