Wed, Apr 16, 2003
DATE: April 15, 2003
AD #: 2003-08-52
This emergency airworthiness directive (AD) 2003-08-52 is
sent to all owners and operators of GE Aircraft Engines (GEAE)
CT7-9B turboprop engines. These engines are
installed on, but not limited to Saab Aircraft AB 340B airplanes.
[Note: it is also found on the S-92, Bell 214, CASA
CN-235, and Sukhoi 80, among others --ed.]
Background
This emergency AD is prompted by reports of 12 compressor stall
events that occurred over a six month period. This is in contrast
to recent historical experience of four to six stall events per
year.
The
stall events have occurred on deceleration when transitioning from
takeoff power to climb power. Of the 10 events under investigation,
nine had the compressor variable geometry (VG) rigged to the
VG schedule N1. The manufacturer’s maintenance manuals and
related service bulletins permit the compressor VG to be rigged to
either the VG schedule N or the VG schedule N1. The VG schedule N
provides a higher stall margin at the expense of a small reduction
of engine performance margin as compared to the VG schedule N1.
Since 1992, the manufacturer has recommended that overhaul shops
use the VG schedule N only. VG schedule N provides more stall
margin on used engines, which inherently have a lower stall margin
due to wear or deterioration. Other factors that contribute to
lower stall margins include dirty compressors and the increased
compressor clearances that occur during the first takeoff of the
day. This condition, if not corrected, could result in a dual
engine in-flight shutdown or power loss due to a compressor stall
during deceleration from takeoff power to climb power.
This AD is issued under 49 U.S.C. Section 44701..., and is
effective immediately upon receipt.
Please see the AD itself for additional information.
FMI (pdf): AD
More News
Maximum Authorized Altitude A published altitude representing the maximum usable altitude or flight level for an airspace structure or route segment. It is the highest altitude on >[...]
Aero Linx: Soaring Safety Foundation (SSF) The Soaring Safety Foundation (SSF) is the Training and Safety arm of the Soaring Society of America (SSA). Our mission is to provide ins>[...]
From 2013 (YouTube Version): Dracula Lives On Through Kyle Franklin... and We're NOT Scared! ANN CEO and Editor-in-Chief, Jim Campbell speaks with Aerobatic and airshow master, Kyl>[...]
“For Montaer Aircraft it is a very prudent move to incorporate such reliable institution as Ocala Aviation, with the background of decades in training experience and aviation>[...]
Also: ForeFlight Upgrades, Cicare USA, Vittorazi Engines, EarthX We have a number of late-breaking news highlights from the 2024 Innovation Preview... which was PACKED with real ne>[...]