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able period of months, a deadline of hours being placed on the service life of the former. Following another incident of in-flight blade failure, this program was accelerated and all of the defective type were out of service in approximately two weeks, as contrasted with the prolonged initial replacement program. The slower program, it developed, had been predicated on the deadline of hours, mentioned previously, which had been based mainly on financial considerations rather than on, we think, a conservative technical evaluation of potential seriousness of the already demonstrated hazard. 
In cases such as these we feel strongly that intuitive judgement of the situation is often sounder than one based on statistics, particularly when they are financial ones. It is granted that such a judgement is often hard to defend, but the terrific cost to an airline, as well as to the industry in general, of a fatal accident should bear more weight than it often apparently does in high executive circles.
Leaving the design and development aspect of operations, we can logically progress to the actual flying of the equipment by the pilots. Occasionally the statement is heard that the pilots have not progressed with the industry. In this connection it is pertinent to note the increased complexity of airline cockpits. Over the years, the instruments, controls,

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and gadgets have increased from 289 for the DC-3, to approximately 400 for the DC-4, 522 for the CV-240, some 600 to 700 for the DC-6, to about 1000 for the B-377. Ten years ago how many people had ever heard of V1, V2, ADI, TBS, TAI, RMI, VAR, VOR, ILS, Mach limitation, etc? It is granted that the gadgets all have their purpose and have contributed to the increased level of safety, but who can say that they have really made the pilot's job easier? In fact they have greatly increased the chances for confusion and mistakes, and the fact that the percentage of accidents attributed to "pilot error" has not increased with the increased complexity, but has remained relatively constant, is, we feel , proof of the adaptability and professional progress of the pilot group.
Simultaneously with this increased instrumentation and gadgetry has come the lowering of minimums and the raising of approach and stalling speeds. Ten years ago the common weather minimum was 500' and 1 mile and the common approach speed was 90mph. Today at some fields we find minimums lowered to 300' and 1/2 mile while the approach speed has risen to 150 mph. True, the alignment problem is more accurate solved by ILS, but, nevertheless, the time available for the pilot to orient himself properly after becoming "visual" has decreased tremendously from 40 seconds to 12 seconds. In

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