Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
CE-08-35
July 16, 2008
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin (SAIB) advises you,
aircraft owners, operators, maintenance organizations, and parts
distributors, to inspect the Honeywell KTR 2280 MMDR for the potential
of improper 8.33 kHz operation and upgrade them to bring back to
conformance with type design.
Background
This SAIB is prompted by Honeywell International Inc.’s self-disclosure
to the Wichita Aircraft Certification Office that their KTR 2280 MMDR,
part number (P/N) 069-01037-0101, is in noncompliance with TSO-C37d
Class 5 and TSO-C38d Class E. The KTR 2280 MMDR can experience improper
operation if the power is interrupted while it is channeled to some
8.33 kHz channels.
The KTR 2280 MMDR remains functional for 25 kHz channel operation. At
this time, the airworthiness concern is not an unsafe condition that
would warrant airworthiness directive (AD) action under Title 14 of the
Code of Federal Aviation Regulations (14 CFR) part 39.
Honeywell International Inc. has issued two service bulletins (SB):
SB KTR 2280-34-02, which limits KTR 2280 MMDR, P/N 069-01037-0101, to 25 kHz channel operation only; and
SB KTR 2280-34-03, which can be used to upgrade P/N 069-01037-0101 to P/N 069-01037-0102.
Recommendations
Honeywell International Inc. has corrected the 8.33 kHz channel
operation and received TSO-C37d Class 5 and TSO-C38d Class E approval
for their KTR 2280 MMDR, P/N 069-01037-0102. We recommend that you
inspect your aircraft, aircraft records, and or parts inventories for
Honeywell KTR 2280 MMDR (P/N 069-01037-0101) and contact Honeywell
International Inc. at the address below for unit upgrade per Service
Bulletin SB KTR 2280-34-03.
The units that may exhibit improper 8.33 kHz operation are P/N 069-01037-0101, all serial numbers.