AD 80-18-03

80-18-03 PIPER (Ted Smith): Amendment 39-3900. Applies to Aerostar Model 601 and 601P series airplanes certificated in all categories.

Compliance required as indicated, unless already accomplished.

To prevent possible engine failure due to excessive lean fuel/air mixture, accomplish the following:

(a) Within 30 days from the effective date of this AD, index and mark the left hand and right hand engine fuel pressure gauges with a yellow arc between the 12 psi and 18 psi range, and incorporate provisions in the Airplane Flight Manual Operations Limitations Section as follows:

1. In the Power Plant Instruments paragraph and under the Yellow ARC Caution column of the fuel pressure data add "12 -18 psi"

2. In the Fuel System Limitations paragraph add the statement "Fuel boost pump must be "ON" when fuel pressure indication is less than 18 psi and engine is operating above idle power."

(b) 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 the modifications required by this AD.

(c) Alternative modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region.

This amendment becomes effective October 6, 1980.