The Operator's Airplane and Engine Requirements 300032
CAUSES of troubles and expense to air-transport companies in their airplanes are dealt with comprehensively by the operations manager and a division superintendent of the National Air Transport. Commercial operation is asserted to be the proving ground for the products of both airplane and airplane-engine manufacturers, and four reasons given for this are (a) lack of understanding between the manufacturer and the purchaser as to precisely what is required of the airplane purchased, (b) inability of the manufacturer to deliver a product equal to his anticipation, (c) inability of the operator properly to use and care for the equipment furnished, and (d) the varied and opposed uses to which different operators must put their equipment.
Detailed and valuable information is given regarding the parts that give trouble and what should be done to avoid it. Reliability and ease of maintenance are emphasized as major needs of the operator, about 22 per cent of whose total expense is for labor and parts to keep the airplanes in the air. Designers and manufacturers' service managers are urged to get out into the field and become familiar with operating conditions and service requirements. Closer cooperation between airplane and engine manufacturers and between both of these and the operators is also urged.
More consideration should be given to engine durability than to weight, horsepower and fuel consumption. Airplane and accessory manufacturers are recommended to make more use of the S.A.E. HANDBOOK, and operators are advised to get together and agree upon the type of fittings they should use for plumbing installations.
The extended discussion* relates in large part to what should be the cruising engine-speed and whether the engine output should be rated at full or part throttle. Misunderstanding and difficulty in learning the exact causes of complaints are attributed to failure of operators to designate parts by their correct names and to lack of complete information of operating conditions by the suppliers of equipment.
Periods between overhauls are said to vary with different operators from 200 to 750 hr., apparently with satisfactory results in each case, and so many factors enter into the matter that great difficulty is experienced in analyzing the causes for the wide variation.