25 May 2011: BELL 47G-3B-1 — Scotts Helicopter Services Inc

25 May 2011: BELL 47G-3B-1 (N96SH) — Scotts Helicopter Services Inc

No fatalities • Lakeville, MN, United States

Probable cause

The loss of engine power due to a loose B-nut on the compressor discharge pressure bleed line.

— NTSB Determination

Accident narrative

On May 25, 2011, about 1140 central daylight time, a Bell 47G-3B-1, N96SH, experienced a total loss of engine power while maneuvering near Lakeville, Minnesota. The pilot subsequently made a forced landing on a swamp near Lakeville, Minnesota. The certificated commercial pilot sustained serious injuries. The helicopter sustained substantial damage to the fuselage and tailboom when it impacted terrain during the forced landing. The helicopter was registered to and operated by Scotts Helicopter Services Inc under the provisions of 14 Code of Federal Regulations Part 137 as an aerial application flight. Visual meteorological conditions prevailed and no flight plan had been filed for the flight that originated from Flying Cloud Airport (FCM), Minneapolis, Minnesota.

Examination of the engine (Rolls Royce Allison T63A700, serial number AE-400951) by a Federal Aviation Administration inspector from the Minneapolis Flight Standards District Office revealed that the Pc bleed line (from the governor to the fuel control) was leaking at the B-nut, which had come loose. The inspector stated that the operator had a spare engine at it facilities and that engine had torque lines painted onto the engine's fittings. The accident engine did not have torque lines painted onto its fittings.

The inspector stated that there is no requirement to use torque lines and that the new engine maintenance manuals now discuss the use of torque lines.

The time since the engine's last inspection was 59.4 hours.

Contributing factors

  • cause Engine bleed air system

Conditions

Weather
VMC, wind 070/10kt, vis 10sm

Loading the flight search…

What you can do on Flight Finder

  • Search flights between any two airports with live fares.
  • By aircraft — pick a plane model (e.g. Boeing 787, Airbus A350) and see every route it flies from your origin.
  • Route map — click any airport worldwide to explore its destinations, or draw a radius to find nearby airports.
  • Global aviation safety — aviation accident database, 5,200+ records since 1980, with map and rankings by aircraft and operator.
  • NTSB safety feed — recent U.S. aviation accidents and incidents from the official NTSB CAROL database, updated daily.

Frequently asked questions

How do I search flights by aircraft type on FlightFinder?

Pick an aircraft model — Boeing 737, Airbus A320, A380, Boeing 787 Dreamliner and more — enter your origin airport, and FlightFinder shows every route that plane flies from there with live fares.

Which aircraft types can I filter by?

We support Boeing 737/747/757/767/777/787, the full Airbus A220/A319/A320/A321/A330/A340/A350/A380 family, Embraer E170/E175/E190/E195, Bombardier CRJ and Dash 8, and the ATR 42/72 turboprops.

Is FlightFinder free to use?

Search and schedules are free. Pro ($4.99/month, $39/year, or $99 one-time lifetime) unlocks the enriched flight card — on-time stats, CO₂ per passenger, amenities, live gate & weather — plus My Trips with push alerts.

Where does the route data come from?

Live schedules come from Amadeus, AeroDataBox and Travelpayouts. Observed routes (which aircraft actually flew a given city pair) are crowdsourced from adsb.lol ADS-B data under the Open Database License.