Story ID: 
ACSR Introduces Tailboom Motion Detection System
By: Mark Huber
Caption: A switch illuminates the master caution panel indicating “tailboom” in the event of a failure.
Word Count: 368
A fatal tailboom separation on a Bell UH-1B in 2013 inspired Aircraft Structural Repair (ACSR) of Stevensville, Mont., to design the Bart tailboom motion-detection system. Bart is currently being offered under FAA Part 337 field approval pending supplemental type certificate (STC) approval.

The system is named after pilot Bart Colantuono, who perished in the crash while logging in heavily wooded terrain near Detroit, Ore. Witnesses reported that when the helicopter was just above the trees, they either saw or heard the load of logs release early and hit the ground hard. After looking up, they saw the helicopter’s tailboom separate from the fuselage; both descended through the trees. The fuselage hit the ground inverted and the tailboom came to rest about 140 feet away. Tailboom fittings on UH-1s can fracture after many years of service.

ACSR president Dustin Wood worked with UH-1 operators in developing the Bart system.

Bart installs via a fuselage plug and consists of a rod encased in tubing to the interior of the tailboom and extending forward into the fuselage where a micro switch is attached to the airframe. Upon failure of an upper left hand tailboom fitting, longeron, or attach bolt, the switch will illuminate the master caution panel indicating “tailboom.” Requiring two days to install, it has been fitted to three UH-1Bs and has already proved its worth, according to Wood.

On February 14 this year, the Bart tailboom warning light illuminated on a UH-1B performing Part 133 external loading as part of a logging operation. Concurrent with the tailboom light and the master caution warning, the pilot reported hearing a loud boom. He immediately removed all left pedal input, released the load and landed without incident using minimal left pedal. An inspection of the helicopter revealed cracks in the left-hand tailboom fitting as well as the sheet metal former on the upper left-hand tailboom bulkhead. Visual inspections immediately before this flight did not reveal any harbingers of a problem such as visible cracking or rivet smoking.

“It is nice to see operators and mechanics working together to come up with solutions that can save lives,” said ACSR’s Wood.