EASA Regulations for Eurocopter Deutschland MBB-BK 117 C-2

Uncommanded Engine In-Flight Shutdown triggered by the Tachometer Box

EASA Safety Information Bulletin SIB No. 2012-19R1 addresses uncommanded engine in-flight shutdowns triggered by the tachometer box on Turboméca ARRIEL 1E2 and ARRIEL 1S1 engines. These engines are installed on Eurocopter Deutschland MBB-BK 117 C-1 and C-2 helicopters, as well as Sikorsky S-76A and S-76C series helicopters. The bulletin provides information on the issue and recommends modifications to improve tachometer box reliability and mitigate shutdown risks.