AD 79-01-05

79-01-05 PIPER (TED SMITH): Amendment 39-3387 as amended by Amendment 39-3643. Applies to Aerostar Models 600, 601, 601P Airplanes certificated in all categories.

Compliance required as indicated.

To reduce the possibility of double engine failure due to fuel starvation, accomplish the following unless already accomplished:

(a) Within the next 10 days after the effective date of this AD accomplish the following:

(1) On airplanes serial numbers 0001 through 0255 inclusive, install a low fuel warning light system which provides a warning when the fuel quantity in the fuselage fuel tank is at or below 12 + 1 -0 U.S. gallons. (NOTE: Aerostar Kit Option No. 156-1 provides an acceptable means of complying with this requirement provided the warning level is set at 12 + 1 -0 U.S. gallons.)

(2) On airplanes serial numbers 0256 and subsequent, adjust the existing low fuel warning light system to provide a warning when the fuel quantity in the fuselage fuel tank is at or below 12 + 1 -0 U.S. gallons. (NOTE: Aerostar Kit Option No. 157-1 provides an acceptable means of complying with this requirement provided the warning level is set at 12 + 1 -0 U.S. gallons.)

(3) On all airplanes, install Aerostar placard P/N 030100-1, on the cockpit instrument panel in clear view of the pilot and revise the Airplane Flight Manual by incorporating FAA approved Aerostar revision dated November 7, 1977.

(4) On all airplanes:

i. Check the condition of the rubber O-ring seal on each wing fuel filler cap to ensure it is capable of forming a positive seal. Replace the O-ring prior to further flight if deterioration is found.

ii. Check the fuel filler cap receptacle in each wing to ensure that the cap can be tightly sealed. Damaged or deformed receptacles must be replaced prior to further flight.

iii. Check and ensure that the wing fuel filler cap locking tabs provides a positive lock indicating sufficient compression of the O-ring to forma positive seal.

(5) The checks required by Paragraph (a)(4) of this AD may be performed by the pilot. (NOTE: For the requirements regarding the listing of compliance and method of compliance with this AD in the airplane's permanent maintenance record, See FAR 91.173.)

(b) Within the next 30 days after the effective date of this AD, and thereafter at intervals not to exceed one year since the last inspection, accomplish the following on the wing fuel tank filler caps:

(NOTE: Aerostar Service Bulletin 600-77 addresses the subject of fuel cap security.)

(1) For airplanes having Shaw Aero filler caps (P/N 431-248), inspect the caps and ensure that the cap locking tab provides a positive lock by measuring the opening pull force at the finger tab with a tension indicator (e.g. "fish scale") aligned approximately 75 degrees from the plane of the cap as follows:

i. Measure the opening pull force on the tab with the cap uninstalled (tab friction force). The tab friction force must not exceed 2 pounds. If the force is greater than 2 pounds, inspect for wear, dirt, corrosion, etc. under tab and clean as necessary to reduce the friction force or replace the cap with a serviceable cap before further flight.

ii. Measure the opening pull force on the tab with the cap installed in the wing receptacle. If the opening pull force is outside the range of 16 + 3 pounds, before further flight, adjust cap by removing cotter pin, turn adjusting nut (clockwise to increase, counterclockwise to decrease) to achieve required pull force, and install new cotter pin to prevent the nut from loosening during service.

(2) For all airplanes, ensure that each wing tank filler cap forms a positive seal by accomplishing this "Leak and Pressure Testing" procedures specified in Section 4 of the Aerostar Maintenance Manual, or in accordance with the following procedures:

i. Completely fill the wing tanks to the filler neck (capacity) and install filler caps.ii. Park the aircraft in the sun to produce fuel expansion, lower wing tip below the "wings level" attitude, and observe for evidence of fuel leaking from filler cap area. Repeat this process for the opposite wing. (NOTE: If the cap is leaking, the leak should become evident within one hour due to fuel expansion and pressure increase within the wing tank. Fuel may leak from the wing overpressure relief valve during these tests. With wing still lowered, carefully release the filler cap and verify that fuel flows out of the filler port. If fuel does not flow out of the filler port, sufficient fuel expansion has not occurred for a valid test, and, the test must be repeated.)

(c) Within the next 30 days after the effective date of this AD, accomplish the following:

(1) To reduce the maximum usable fuel quantity limitations for flight planning purposes, install a new placard on the instrument panel in clear view of this pilot that reads as follows:

"TOTAL USABLE FUEL165.5 U.S. GAL. FUSELAGE USABLE FUEL 41.5 U.S. GAL. EACH WING USABLE FUEL 62 U.S. GAL."

(2) To show a reduced maximum usable fuel quantity for each wing tank of 62 U.S. gallons, and to ensure first fueling priority is given to the fuselage tank, replace the placard at each wing tank filler location with a placard that reads as follows:

"100/130 or 100LL MINIMUM GRADE AVIATION FUEL. DO NOT ADD FUEL TO WING TANKS UNLESS FUSELAGE TANK IS FULL. EACH WING TOTAL USABLE FUEL 62 U.S. GALLONS. DO NOT INSERT NOZZLE OVER 3 INCHES."

(3) To show a reduced maximum usable fuel quantity in the fuselage tank of 41.5 U.S. gallons, replace the placard at the fuselage tank filler location with a placard that reads as follows:

"100/130 OR 100LL MINIMUM GRADE AVIATION FUEL. FUSELAGE TOTAL USABLE FUEL 41.5 U.S. GALLONS."

(4) Install a new placard on the cockpit instrument panel in the vicinity of the fuel quantity gage to read as follows:

"READ FUEL QUANTITY IN LEVEL FLIGHT ONLY."

(5) Replace the X-feed placard required by Paragraph (a) of AD 77-26-04 with a placard that reads as follows:

"X-FEED LEVEL FLIGHT ONLY. TAKEOFF PROHIBITED WITH LOW FUEL LIGHT ON. DOUBLE X-FEED LIMITED TO LEVEL FLIGHT EMERGENCY ONLY."

(6) Revise the markings on the cockpit instrument panel at the right and left engine fuel selector switches as follows:

AD 79-01-05

(7) Revise the Airplane Flight Manuals with Aerostar supplement dated December 5, 1978, or later FAA-approved revisions to incorporate the following changes:

(i) Reduction of airplane total usable fuel capacity to 165.5 gallons.

(ii) Revised fuel system emergency procedures.

(iii) Added fuel system descriptive material.

(iv) Revised airplane refueling procedures.

(v) Added note to caution against use of fuel flow totalizer as a primary fuel quantity instrument.

NOTE: The placards and Airplane Flight Manual supplements described by Aerostar Service Bulletin 600-79 are acceptable for compliance with Paragraphs (c)(1) through (c)(7). The Airplane Flight Manual supplements are interim revisions that may be replaced by FAA approved revisions that contain the same information, at a later date.

(8) For airplanes which have either a Silverton or Symbolic Display type fuel flow totalizer system installed, which incorporates a preset maximum usable fuel quantity memory, adjust the present quantity to read no more than 165.5 U.S. gallons.

(d) By June 1, 1980, accomplish the following modifications in accordance with a design and procedures approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(1) On or near the centerline of the instrument panel, in clear view of the pilot, install:

i. Three gages that provide a continuous reading of fuel quantities contained in the fuselage tank and in each of the wing tanks; or

ii. A single gage that provides a continuous reading of fuel quantity contained in the fuselage tank and will, upon switch selection by the pilot, provide a reading of fuel quantity contained in each wing tank.

(NOTE: Fuel gage modifications to meet the requirements of paragraph (d)(1) are being developed by Piper Aerostar. Proposed modifications may also be presented by other persons for approval.)

(2) Install and test an overpressure relief valve in each wing fuel tank which has a pressure relief setting of 1.2 to 1.5 psi. For airplanes which already have an overpressure relief valve installed, test to ensure pressure relief is provided at 1.2 to 1.5 psi. (NOTE: Piper Aerostar DWG. 106068 provides an acceptable means of installing overpressure relief valves.)

(3) Revise the Airplane Flight Manual and placards in the cockpit as necessary to envisage the modifications approved for compliance with Paragraph (d)(1).

(e) Previous compliance with AD 77-26-04 satisfies compliance with Paragraphs (a)(1) or (a)(2), and (a)(3) of this AD.

(f)Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections required by this AD.

(g) Equivalent inspections, modifications, Airplane Flight Manual revisions, placards, and repairs may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region.

This supersedes Amendment 39-3103 (42 FR 64111), AD 77-26-04, as amended by Amendment 39-3135 (43 FR 5506).

Amendment 39-3387 become effective February 2, 1979.

This Amendment 39-3643 becomes effective December 27, 1979.