Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
CE-20-09
May 13, 2020
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin (SAIB) informs
registered owners/operators of an airworthiness concern for M7
Aerospace LLC, Models SA227 airplanes (under Type Certificate Data
Sheets A5SW, A8SW and A18SW), all serial numbers, of an airworthiness
concern. Specifically, this SAIB requests inspection and reporting of
crack, damage, buckle, and/or wrinkle of the Nacelle keelson web and
its surrounding structural areas.
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 Regulations (14 CFR) part 39.
Background
In June 2003, M7 Aerospace issued Service Letters 226-SL-030,
227-SL-046, CC7-SL-038 due to a report of damage seen on the Nacelle
keelson webs adjacent to the heavy drag brace fitting. Typical damage
is cracking and/or buckling of the keelson web at Nacelle Station (NS)
141.69 just aft of the drag brace fitting. There are two specific
areas, one is located in the lower region of small vertical strip of
web between the door hinge and the drag brace fitting (27-35162); the
other is near the top of the drag brace fitting in the web immediately
aft of the drag brace fitting.
Later in the 2017 time frame, more reports were received of cracks in
the right-hand (RH) and left-hand (LH) Nacelle upper NS 80.87 leading
edge rib, just below and forward of the 27-31130 spar straps at Wing
Station (WS) 136/137. Areas of interest included RH battery box WS
80.87 Outboard upper rib 27-31023-044.
M7 Aerospace has observed cracking in the webs and generally issued a
Limited Approved Repair (LAR) repair to owners and operators, which is
presently being incorporated into the Structural Repair Manual (SRM).
Recommendations
The FAA recommends affected M7 Aerospace owners and operators inspect
for crack, damage, buckle, and wrinkle in the nacelle keelson webs at:
LH and RH Nacelle upper NS 80.87 leading edge, just below and forward of the spar straps at WS 136/137.
RH battery box WS 80.87 out board upper rib.
Nacelle keelson web at NS 141.69, just aft of the drag brace fitting.
The FAA recommends that M7
Aerospace owners and operators report any finding of damage, crack,
buckle or wrinkle to the FAA points of contact listed below. Providing
this information is strictly voluntary, but please review the following
notice:
A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to a penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a current valid OMB Control Number. The OMB
Control Number for this information collection is 2120-0056. Public
reporting for this collection of information is estimated to be
approximately 5 minutes per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information. All responses to this collection of
information are voluntary. Send comments regarding this burden estimate
or any other aspect of this collection of information, including
suggestions for reducing this burden to: Information Collection
Clearance Officer, Federal Aviation Administration, 10101 Hillwood
Parkway, Fort Worth, TX 76177-1524.
For Further Information Contact
Jacob Fitch, Aerospace Engineer, AIR-7F2, Fort Worth ACO Branch, 10101
Hillwood Pkwy, Fort Worth, TX 76177; phone: (817) 222-4130; email:
jacob.fitch@faa.gov
Hung V. Nguyen, Aerospace Engineer, AIR-7F1, Fort Worth ACO Branch,
10101 Hillwood Pkwy, Fort Worth, TX 76177; phone: (817) 222-5155;
e-mail: hung.v.nguyen@faa.gov
For Related Service Information Contact