Refan

A new engine would have to be markedly superior not only to the JT8D but also to a JT8D or Rolls-Royce Spey refanned to a higher bypass ration.

Senator Goldwater, in reducing the funding in the program, we looked very hard at the benefits that would accrue to refanning the JT8D as compared with the JT3D.

In our July, 1974, statement, we presented preliminary test results on the effect on sea level fuel consumption of refanning an experimental engine.

The results of refanning new JT8D aircraft in combination with other noise reduction options are shown in figures lz and l3 for 1981.

In considering the relative merits of SAM versus refan in our rule-making efforts, we have considered the following factors as being of primary significance.

The refans have lower acquisition and maintenance costs, which favourably trade off against their higher fuel consumption to produce economical operation, particularly at shorter ranges.

The manufacturer installed three JT8D-115 refans, developed by Pratt & Whitney under contract to NASA, on a 727 for flight tests at Boeing's Boardman, OR, airfield.