51-05-01 PRATT & WHITNEY: Applies to Douglas DC-6 and Convair 240 Aircraft Equipped With R-2800-34M1, -83AM3, -83AM4, and Double Wasp CA Series Engines Using Antidetonant Injection (Wet Power) for Takeoff.
Compliance required as soon as possible but not later than February 15, 1951.
A. Each operator of an airplane covered shall select a power which he undertakes to maintain. If that power is less than the corresponding value available during the type certification tests of the airplane, the operating weights of the entire fleet shall be reduced to values such as will enable the airplanes to perform as indicated in the approved airplane flight manual with the power selected.
B. The power actually develop by each engine shall be measured each time it reaches each of the following stages.
1. Upon installation of overhauled engines in aircraft.
2. At the No. 3 inspection nearest to the midpoint of the authorized service time between overhauls.
3. At thenearest No. 3 inspection or some convenient point near or at the end of the authorized service time between overhauls.
C. The procedures and methods employed in making these power measurements shall be acceptable to the FAA.
1. The frequency of the power measurements should be contained as indicated above until the results obtained on each operator's fleet have been evaluated for the purpose of establishing whether more frequent or less frequent measurements are warranted.
2. Operators not employing line maintenance practices which will reasonably insure the continued availability of the selected power will start this program making more frequent power measurements than indicated above.
D. An airplane incorporating an engine which at any of the required power measurements, fails to develop the selected power shall not be dispatched unless:
1. The power is restored to the selected value, or
2. The engine is replaced by one developing the selected power, or
3. The operating weights of the individual airplane are reduced as specified in A.
E. If, on a fleet-wide basis, the initial powers measured during any individual power measurement are consistently below the selected power, the operator shall:
1. Initiate or improve line maintenance to the extent necessary to give reasonable assurance that the selected power is continuously available, or
2. Make more frequent measurements of power, or
3. Select a lower value of power representative of the initially measured values and reduce operating fleet weights as specified in A.
F. An acceptable method for power measurement and data correction utilizing static ground runups in the aircraft is described by AAL in their instructions on "Convair Ground Power Check". This information has been distributed by ATA to all the airlines involved. Alternative methods providing equivalent or greater accuracy will be acceptable.
G. Results of the above power checksare to be submitted regularly and promptly to the assigned FAA Field Agents.