Pratt sues Rolls over patent

The US aircraft engine-maker Pratt & Whitney sued its British rival Rolls-Royce yesterday, claiming that a Rolls-Royce patent on a fan blade it uses in jet engines is invalid.

Pratt's suit, filed in Connecticut, is a counter-move to an earlier Rolls-Royce complaint, filed in May in Virginia, which charged the United Technologies Corp unit with violating a Rolls-Royce patent on fan blades, one of the most visible components at the front of a jet engine.

Pratt, which aims to sell its next-generation geared turbofan engine to Airbus or Boeing, contends that Rolls filed its suit in part to attempt to prevent its US rival from selling its geared turbofan engine. It contends that Rolls was issued a patent based on an aspect of blade design that had been long used by engine makers.