By Tommy H. Thomason

Wednesday, September 9, 2009

Missed It by That Much IV

In 1954, McDonnell proposed what was to become the F4H Phantom with two different engines, the Wright J65 or the General Electric J79. In this F3H-G/H mockup, the J65 is represented on the left side and the J79, on the right. The former was a license-built Armstrong Siddeley Sapphire, which was not only flight rated, but flying in new aircraft, including the Navy's F11F. The latter had only run for the first time in June 1954 and would not be flight rated for more than a year. The J65-powered F3H-G was projected to have a top speed of Mach 1.52 and the J79-powered F3H-H, Mach 1.97.

In late 1954 or early 1955, the admirals selected the J79 for the new F3H, in spite of their (and McDonnell's) recent and horrible experience with a not only new but unproven engine, the Westinghouse J40, which caused major delays and cost overruns in the Navy's early 1950s fighter programs. As it happened, the J79 was a success, meeting or exceeding expectations. Meanwhile, the proven (except for the Wright-furnished afterburner) J65 proved a huge disappointment for Grumman. The F11F, instead of reaching its guaranteed top speed of Mach 1.2 or better, was barely supersonic in level flight due to lower than projected thrust in afterburner. Subsequently evaluated with the J79, it could slightly exceed Mach 2.

In late 1958, the Navy was forced by Congress to choose between the F4H and the F8U-3 for its fleet air defense fighter requirement. Both were demonstrated to have near Mach 2 performance. The decision came down to the belief that the radar operator in the two-seat F4H would be able to acquire and begin the process of launching a Sparrow air-to-air missile at an incoming Soviet bomber just a few seconds quicker than the pilot of the single-seat F8U-3, possibly making the difference in keeping the bomber from accomplishing its mission to destroy an aircraft carrier. However, if the F4H had been saddled with the anemic J65, the decision might well have gone the other way: it's possible that the F8U-3 getting in range for a missile launch sooner would have been found to more than make up for the quicker target acquisition provided by the radar operator in the F4H. If so, the F4H would now only be known to aviation historians like me rather than as an iconic jet fighter of the 1960s and 1970s and the holder of several speed and time-to-climb records.

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