ANC16LA022

The pilot's failure to maintain terrain clearance while on approach to land in flat light conditions. Contributing to the severity of the pilot's injuries was the inadequately restrained internal cargo, which shifted forward during the impact and struck the pilot and/or the pilot's seat.

The instrument-rated commercial pilot was making a visual flight rules internal-cargo company flight in the helicopter. He reported that flat light conditions were present as he made a visual approach for landing at a remote dog camp situated on a glacier. During the approach, the helicopter impacted terrain, coming to rest about 3/4 mile from the dog camp. The pilot reported that there were no preimpact mechanical anomalies with the helicopter and characterized the accident as controlled flight into terrain. It is likely that the pilot failed to maintain terrain clearance due to his inability to distinguish distances and closure rates because of the flat light optical illusion. The single cargo strap securing a plastic box containing a metal heater to the rear cabin floor remained intact during the accident sequence; however, the plastic box shifted forward due to the momentum of the helicopter impacting terrain, which allowed the metal heater to escape from the lidded box. It is likely that the metal heater struck the pilot and/or the pilot's seat in the accident sequence, contributing to the serious injuries sustained by the pilot. The single cargo strap used to secure the plastic box was installed such that it provided lateral restraint of the box but no forward restraint of the box. If the box had been restrained to prevent forward movement, it is likely that the metal heater would not have escaped from the box. Review of the helicopter's rotorcraft flight manual (RFM) revealed that it provided only a total weight limit for the rear cabin floor and did not provide any guidance about how to properly secure internal cargo in the cabin. Further, although the manufacturer indicated in a systems manual that cargo could be secured to the cabin floor using 11 mooring points embedded into the floor and provided a force limit for each mooring point, the systems manual provided no guidance regarding how the cargo should be attached to the mooring points; for example, no information was provided about the type and number of restraints to be used or how they should be configured. Airbus, the manufacturer of the helicopter, stated that it was the responsibility of the operator "to define an adapted cargo, freight, or baggage securement that is in respect to the limitations permissible force on the floor stowing mooring rings." The Federal Aviation Administration (FAA) stated that operators do not have certification approval to install cargo in the cabin unless it is mentioned in the RFM or RFM supplement and that, if an FAA-approved cargo configuration has been published for a specific aircraft, the RFM for that aircraft is where information on how and where to install cargo will be found. However, the FAA also stated that it "is not aware of any documentation that would prohibit Part 27 rotorcraft from carrying cargo in the cabin, even if a certification does not exist for that helicopter."

Era Flight Risk Assessment The Era Operations Manual – Part A General Procedures discusses flight risk assessment and states, in part: A risk assessment shall be completed at the beginning of each flight day and updated when conditions warrant. Pilots shall not initiate a flight or series of flights until a risk assessment has been performed. The pilot conducted a formal flight risk assessment before the flight using Risk Assessment Form ERA A-003. The form had sections addressing crew qualifications, crew currency, duty period, flight profile, environment, and aircraft. The completed flight risk assessment form had a total value of 15, and no sections of the flight risk assessment were exceeded (crew qualifications, crew currency, duty period, flight profile, environment, and aircraft). The flight would have been prohibited if the total value was greater than 32 or any section limit was exceeded. Company VFR Weather Minimums The Era Operations Manual – Part A General Procedures discusses company VFR weather minimums and states that, for overland day VFR flights, a minimum operating height of 500 ft, a cloud base of 600 ft, and 3 statute miles visibility is required for all aircraft and aircrews. The manual also states that the VFR weather minimum shall be 100 ft of vertical separation from the cloud base, and VFR flights may not depart or continue if the reported weather conditions at departure, en route, or at the destination are below the company VFR weather minimums. The manual further states that a flight in VFR weather conditions that does not meet the company VFR weather minimums may only be made with approval from the Director of Operations, Chief Pilot, or applicable Regional Operations Manager after a risk assessment and deviation request has been documented. The Era Operations Manual – Part A General Procedures has dedicated sections that address flight operations in deteriorating VFR weather conditions (such as reduced visibility and ceilings), IIMC avoidance procedures, and IIMC recovery procedures. Flat Light Conditions Operational Procedures The ERA Operations Manual – Part A General Procedures discusses company operational procedures for flat light conditions and states, in part: The pilot in command shall use the radar altimeter for altitude reference when flying over large, flat areas, (glaciers, swamps, glassy water, etc.). Monitor airspeed, radar altimeter, and vertical speed more often during approaches in flat light conditions. The pilot in command shall ensure there is a good reference point during approach and landing. Losing sight of the reference point may require a go around. Maintain a good scan without fixating on a point. Era Internal Cargo Operations The Era Operations Manual – Part A General Procedures discusses internal cargo carried in passenger compartments and states: For the purposes of clarity, baggage may be carried in a passenger compartment when properly secured and accompanied by a passenger. Cargo may only be carried in the passenger compartment during cargo only operations. The PIC shall ensure that all cargo, including baggage, on Company aircraft complies with the following: It is carried in an approved cargo rack, bin, or compartment installed in or on the aircraft; It is secured by an approved means. The manual further discusses how the cargo is carried and states: Properly secured by a safety belt or other tiedown having enough strength to eliminate the possibility of shifting under all normally anticipated flight and ground conditions; It is packaged or covered to avoid possible injury to occupants; It does not impose any load on seats or on the floor structure that exceeds the load limitation for those components; It is not located in a position that obstructs the access to, or use of, any required emergency or regular exit, or the use of the aisle between the crew and the passenger compartment, or located in a position that obscures any passenger's view of the "seat belt" sign, "no smoking" sign, or any required exit sign, unless an auxiliary sign or other approved means for proper notification of the passengers is provided; For cargo only operations, this does not apply if the cargo is loaded so that at least one emergency or regular exit is available to provide all occupants of the aircraft a means of unobstructed exit from the aircraft if an emergency occurs; and It is not carried directly above seated occupants. The operator reported that internal cargo loading is covered in company training and performed by company employees. The operator further reported that the only individuals who have documented cargo training are the pilots, and due to this, all internal cargo loading is supervised and/or approved post-loading by the pilot who has the final authority for airworthiness of the helicopter. At the time of writing of this report, the operator has sold their Alaska-based business line that supported dog mushing operations on glaciers. The pilot was seated in the front right seat and was wearing a 4-point restraint system at the time of the accident. The pilot did not wear and was not required to wear a flight helmet. Review of the pilot's postaccident medical treatment records indicated that his injuries included fractures of multiple left ribs and the left scapula, multiple left-sided transverse and spinous process fractures, as well as injuries to the left lung, left kidney, and spleen, and an intimal tear in the mid-descending aorta. Carriage of Internal Cargo in Airbus AS 350 Series Helicopters The NTSB IIC submitted multiple inquiries during the investigation to the FAA Office of Accident Investigation and Prevention, Washington, DC, regarding the carriage of internal cargo in the Airbus AS 350 series. On March 28, 2017, the FAA responded, in part: The FAA does not require original equipment manufacturers (OEMs) to publish information regarding cargo loading. The certification assumption is that the helicopter will be used to carry people, unless indicated otherwise by the applicant. In the case of the AS350, Airbus did not indicate that anything other than passengers will be carried. In its March 28, 2017, response, the FAA also stated: Any "approved" cargo installation will be explained in the rotorcraft flight manual (RFM) limitation or supplement section – (what tie-downs are used, what straps are used, etc.); loading instructions (what areas in the cabin get loaded first, second, etc.); and procedures (walk around procedures will mention to verify cargo secured). Operators do not have certification approval to install cargo in the cabin unless it is mentioned in the RFM or [RFM supplement] RFMS (part of the [type certificate] TC or an STC) – installation instructions are provided in the flight manual. It is possible that there may be some operators that have been using existing tie-downs/seat rails to tie down cargo in the cabin, and incorrectly assuming that this is a "certified" installation when in fact it is not. … The RFM or RFM supplement will be clear as to what is approved regarding internal cargo (if it does not mention how and where to install cargo, then it's not certified). In a response on August 25, 2017, the FAA stated, "our position is the same as in the other queries from the NTSB regarding cabin cargo – operators should not be securing cargo in areas unless doing so has been FAA approved (basic design, design change, field approval, etc.)." In a letter dated August 29, 2017, the FAA stated, in part: Also, while a definition for a cargo/baggage compartment in rotorcraft does not exist, the FAA has interpreted this as a compartment (enclosed area) that is separated from the cabin (passenger area). … Additionally, the FAA is not aware of any documentation that would prohibit Part 27 rotorcraft from carrying cargo in the cabin, even if a certification does not exist for