Previously, P&W had previously said that the geared turbofan would make propfan/un ducted fan technology irrelevant.

Pratt Whitney considers geared open rotor concept

By Victoria Moores

Pratt & Whitney has begun studies of open rotor engine architecture despite its long-standing pursuit of geared turbofan (GTF) technology, and does not rule out shifting to a propfan configuration if this path is favoured by the airframers.

The company is developing a GTF engine to power the next generation of regional and single-aisle aircraft. This engine’s low-pressure spool operates at high speeds for peak efficiency, while its fan operates at slower speeds to maximise efficiency and significantly reduce noise.

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