Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
NE-07-49
September 20, 2007
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin (SAIB) alerts you,
owners, operators, and certificated repair facilities of Lycoming four,
six, and eight cylinder reciprocating engines with stainless steel fuel
injector tube assemblies and support clamps, of a potential problem
that could result in a fuel leak, fire, and engine failure.
Background
The correct installation and inspection of the fuel injector lines
is currently described and pictured in Lycoming MSB No. 342E, dated May
18, 2004, and in the Lycoming engine model IO-580-B1A, Maintenance and
Overhaul Manual, Airworthiness Limitations Section (ALS).
Lycoming MSB No. 342E states, “There have been instances of fuel line
breakages where support clamps have been omitted during field overhaul
or repair. The support clamps dampen line vibration due to the impact
of cooling air and vibration from the engine and/or aircraft. Also, the
fuel supply lines between the fuel injector manifold and the nozzles
can become damaged and leak if they are severely bent or kinked during
engine maintenance.” AD 2002-26-01 mandates the same inspections of the
fuel injector lines and clamps as Lycoming MSB No. 342D. In addition,
the NYACO confirmed the failure of a fuel injector line due to a
corrosion pit that resulted in fuel under pressure being sprayed into
the engine compartment. Therefore, when inspecting for the proper
installation of the tubes and clamps, the fuel lines must also be
inspected for evidence of cracking, corrosion, pitting, physical damage
and fuel stains.
Newer Lycoming engine models, such as the IO-580-B1A, and all other
newer engine models, have a Maintenance and Overhaul Manual with an ALS
that contains instructions for continued airworthiness. Since Lycoming
has included the installation and inspection of the fuel injector lines
in the ALS for the newer engines models, these engine models will not
be included in a Lycoming Mandatory Service Bulletin (MSB) or in a
corresponding FAA Airworthiness Directive (AD) that describes the
correct installation and inspection of these lines. Therefore, if your
Lycoming fuel injected engine model has a Maintenance and Overhaul
Manual with an ALS, the ALS must be consulted for the correct
installation and inspection of the fuel injector lines.
Newer engines, for which an ALS is applicable, might be modified with
equipment clamped to the fuel injector lines. This equipment might be
installed by a Field Approval, a Supplemental Type Certificate (STC),
or by an aircraft manufactures Type Certificate (TC).
If your Lycoming fuel-injected engine model does not have a Maintenance
and Overhaul Manual with an ALS, Lycoming MSB No. 342 must be consulted
for the correct installation and inspection of the fuel injector lines.
Older engines, for which Lycoming MSB No. 342D is applicable, might be
modified with equipment clamped to the fuel injector lines. This
equipment might be installed by a Field Approval, a Supplemental Type
Certificate (STC), or by an aircraft manufactures Type Certificate
(TC). For these older, modified engines, AD 2002-26-01 and Lycoming MSB
No. 342D are still applicable. In this case, owners/operators must
request an alternate method of compliance in accordance with Note 2 and
paragraph (d) of AD 2002-26-01 to deviate from the AD. For newer
engines, owners/operators must request a Supplemental Type Certificate
(STC) to deviate from the ALS.
For all Lycoming engines modified with equipment clamped to the fuel
injector lines, the installers of this equipment are responsible for
the airworthiness of such installations. Specifically, the installers
are responsible for ensuring the equipment does not compromise fuel
system integrity, whether by chafing or crimping a line, or otherwise.
Recommendations
The purpose of this SAIB is to provide information and
recommendations; however, when an AD is mentioned in this SAIB, the AD
is still mandatory.
1. We recommend clamping and inspecting the fuel injector lines per the
latest revision of Lycoming MSB No. 342 even when the issuance of a new
AD lags behind Lycoming’s issuance of a revision to Lycoming MSB No.
342. Or, where applicable, clamp and inspect the fuel injector lines
per the Airworthiness Limitations Section (ALS) of the Maintenance and
Overhaul Manual.
2. For older engines modified in the area of the fuel injector lines
and clamps, AD 2002-26-01 and Lycoming MSB No. 342D are still
applicable. In this case, owners/operators must request an alternate
method of compliance in accordance with Note 2 and paragraph (d) of AD
2002-26-01 to deviate from the AD.
3. For newer engines modified in the area of the fuel injector lines
and clamps, the appropriate ALS is applicable. In this case,
owners/operators must request a Supplemental Type Certificate (STC) to
deviate from the ALS.
For Further Information Contact
Norm Perenson, Aerospace Engineer, FAA NYACO, ANE-171, 1600 Stewart
Avenue, Suite 410, Westbury, NY 11590; phone: (516) 228-7337; fax:
(516) 794-5531; email: norman.perenson@faa.gov.
For Related Service Information Contact
Lycoming Engines, 652 Oliver St, Williamsport, PA 17701: phone:
(570) 323-6181; fax: (570) 327-7101; or go to their Web site at:
http://www.lycoming.textron.com/support/publications/servicebulletins/pdfs/SB342E.pdf.