Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
CE-08-25
May 23, 2008
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin is being issued to
alert operators of the Dornier 228 series airplanes of daily checks of
the negative torque sensing (NTS) system that are recommended by RUAG
Aerospace Technology, which manages the continued airworthiness of
these airplanes.
Background
The manufacturer of the engines used on the Dornier 228 series
airplanes, Honeywell, has issued operating information letters (OIL)
for daily cockpit checks of the NTS systems of the TPE331 series turbo
shaft engines installed on the Dornier 228 series airplanes. The NTS
system, if inoperative in the case of an engine failure, can cause
severe airplane controllability problems. In certain circumstances and
altitudes, the airplane may not be recoverable.
At this time, this airworthiness concern is not considered an unsafe
condition that would warrant an airworthiness directive (AD) action
under Title 14 of the Code of Federal Aviation Regulations (14 CFR part
39).
Recommendations
RUAG has issued Flight Operations Information FOI-228-009, which
recommends that the daily NTS checks of Honeywell OIL OI331-20R1 and
OI331-22 (depending on the type of NTS system installed) be done daily.
The FAA recommends compliance with the provisions of the flight
operations information; the provisions of which will be incorporated
into the pilots operating handbook (POH).
For Further Information Contact
Karl Schletzbaum, Aerospace Engineer, Small Airplane Directorate, 901
Locust Street, Room 301, Kansas City, MO 64106; phone: (816) 329-4146;
fax: (816) 329-4090; e-mail: karl.schletzbaum@faa.gov.