One Citation With Aux Tanks Developed Fuel Leaks
The FAA has issued an SAIB for some Citation jets which have auxiliary fuel tanks installed following Sierra Industries, Ltd. Supplemental Type Certificates (STC) SA80RM or SA152RM, of new instructions for continued airworthiness (ICA). The tanks may be on Cessna 500, 501, and 550 airplanes (File image below, left).
The SAIB is the result of a Cessna Aircraft Company Model 501 airplane that developed fuel leaks in the auxiliary fuel tank installed with Sierra Industries, Ltd. STC. Investigation revealed improper maintenance was performed in an attempt to reseal the fuel tank. The ICA introductory paragraph states the Citation maintenance manual structural repairs and tank sealing instructions apply to tank repair and sealing.
However, the FAA and Sierra Industries saw this as an opportunity to revise the ICA and raise awareness of the ICA. In response, Sierra Industries, Ltd. created revised ICA, Document MMS-911, Issue 1, dated November 28, 2011, to expand and clarify inspection requirements and maintenance instructions for the auxiliary fuel tank and fuel system. The new ICA includes maintenance and repair instructions, operational check and trouble shooting procedures, a fuel system schematic and wiring diagram, and major parts list.
The FAA recommends all owners and operators of Cessna Aircraft Company Models 500, 501, and 550 airplanes modified with Sierra Industries, Ltd. STC SA80RM or SA152RM obtain a copy of and comply with the inspection and maintenance requirements contained in Sierra Industries, Ltd. ICA Document MMS-911, Issue 1, dated November 28, 2011.
At this time, the FAA has determined this 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.