Bell 47 G2 F-GAMD Accident at Ampuis

Accident Overview and Immediate Sequence of Events On 24 May 2016 at 06:50 local time, a Bell 47 G2 helicopter, registration F-GAMD, operated by a company, was conducting an aerial work flight at Ampuis (69). After completing the pre-flight inspection, the pilot took off from the transport trailer. The helicopter, with one of its skids still secured to the trailer, tipped over onto its left side and struck the ground. The pilot was slightly injured, and the helicopter was destroyed. ## Site Examination and Contributing Factors An examination of the helicopter and the trailer confirmed that two tie-down straps remained attached to the left skid. The straps were oxidized and had only a few traces of faded red paint. No signaling device was present to indicate their presence. ## Pilot Experience and Operational Context The pilot held a professional helicopter pilot license and a helicopter spraying qualification. He had approximately 5,000 flight hours, including 50 hours in the three months prior to the accident, all on type. On 23 May, a mechanic had transported the helicopter by road on a trailer from the company's headquarters to the takeoff site, an annex to the municipal sports field in Ampuis. Arriving around 19:30 in the rain, the mechanic began preparing the helicopter for the next day's 07:00 flight, which involved removing the tie-down equipment, including four straps (two per skid). He finished around 20:00. On 24 May at 06:45, the pilot and mechanic went to the takeoff site. After the pre-flight inspection, the pilot sat in the left seat and started the engine. The mechanic, on the right side of the helicopter, checked the oil level and then went to the site that would serve as the base for the spraying operations. Neither noticed that the two straps on the left skid had not been removed. Both confirmed that there was no procedure or checklist for securing or unsecuring the helicopter on the trailer. ## Conclusion The accident was caused by the failure to remove two of the four skid tie-down straps from the helicopter's transport trailer, which caused the helicopter to tip over onto its left side during takeoff. Contributing factors included the absence of a procedure or checklist for unsecuring and preparing the helicopter after road transport, the use of tie-down straps whose color made them difficult to distinguish, and the absence of a device to signal the presence of the straps to the pilot or mechanic.