The QF (Quiet Freighter) is a 727-100C or -QC which has been modified to carry RR Tay fan-jets with a by-pass ratio of 1:3. The Tay engines are physically larger than the original JT-8D's as can be seen from the bulging intake of no. 2. Thus the modification is a substantial piece of engineering (rumored to be about 15 mil $ a piece in the 1980's) but the outcome is true Stage III, not just a 'statement-in-paint' as you'll see on some 27's.

    Additional modifications include replacement of the original ADI and HSI with EADI and EHSI, installation of ACARS, SATNAV to B-RNAV (RNP 5) specs, new GPS- and terrain-data based EGPWS and, somewhat unusual for a civilian aircraft, HUD, which is approved for Cat III approaches.

    Installation of Rolls Royce Model TAY 651-54 engines and TR6510 thrust reversers are covered by the SA8472SW STC which belong to The Dee Howard Company of San Antonio, TX, USA.

    United Parcel Service had 58 Tay modified 27's - one by one now beeing retired to the dessert.  A single passenger -100 has also been modified for executive use (no connection to UPS).