Date: 201501
Local time of day: 1801-2400
Flight conditions: VMC
Weather elements / visibility: Rain; Icing
Light: Night
Aircraft: Eurocopter AS 350/355/EC130 - Astar/Twinstar/Ecureuil
Operator: Air Taxi
Operating under: Part 135
Mission: Ambulance
Flight phase: Parked
ATC / advisory: CTAF ZZZ
Reporter organization: Air Taxi
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness; Distraction; Confusion
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Detector: Person Flight Crew
When detected: Aircraft In Service At Gate
Result: Flight Crew Overcame Equipment Problem; Flight Crew Regained Aircraft Control; Flight Crew Took Evasive Action
Contributing factors: Company Policy; Weather
Primary problem: Weather

Narrative: The helicopter was parked on a dolly that was chalked on both sides with heavy rubber chalks and connected to the truck used for towing. Keeping the truck attached to the dolly for takeoff and landing is a standard operating procedure by all pilots. I was parked in the usual start up location; which is between two rows of hangars; with a fence and cars behind me and various small aircraft in between both rows of hangars. The area is a confined; albeit roomy area in my opinion. The ramp surface at the time of startup was ice with pockets of standing water. After starting the helicopter; when slowly advancing the Fuel Flow Control Lever (FFCL) to fly; the dolly; with the helicopter on it; started to rotate to my right (to be clear the nose of helicopter went right; tail of helicopter went left). I immediately aborted the start. The dolly continued to rotate about 60 degrees from its starting point with the tail moving toward our hangar. The tail cleared the hangar by about 25 feet; I was parked squarely in the middle of the allotted area. If I hadn't been attached to the truck; I believe the helicopter would have slid into our hangar. There was no damage to anything. After submitting a safety report in hopes of fixing the safety issues associated with this event; I was informed via email the following:'The Towing Equipment Policy states the following: dollies - tow vehicles shall be moved a safe distance away from dollies during aircraft takeoff and landing. The requirement to maintain 15 feet clearance from obstacles on the ground for takeoff and landing applies as well.'I have never seen the towing equipment policy referenced above. I have read our operations manual more than once and was given adequate operations manual training in my initial new hire class and was aware of the 15 foot rotor disc clearance policy for takeoff and landing. However; I did not realize the 15 feet included the tow truck. I was trained to leave the truck attached to the dolly for reference as this is our standard operating procedure at both bases and by all pilots.Please note: I believe having the truck to use as a visual reference and a solid anchor is imperative for our safety of operations. The truck provides a great visual reference especially in blowing snow and white out conditions which we encounter often.I have operated numerous times; in similar conditions; off the dolly while attached to the truck and chocked and did not realize it would rotate as it did. This should be included in winter operations training for the pilots so they are not caught by surprise; like I was.If the tow truck is not to be attached to the dolly for takeoff and landing (which again compromises our safety of operations); I believe the towing equipment policy should be incorporated into our operations manual and training should be revised to reflect this policy.




Synopsis: An AS-350 pilot described a helicopter dolly rotating on an icy ramp during engine start while preparing to fly off the dolly.