Despite four years of speculation, Gulfstream still has no announced answer to Dassault's Falcon 5X, which was unveiled last October.

More hints about a G450 replacement project – dubbed the P42 – continue to emerge online and in government filings, but Gulfstream executives remain tight-lipped.

"We know what we are going to do next, but we haven't announced what we are going to do next," said Larry Flynn, Gulfstream president, during a recent media demonstration flight on a G550. However, evidence of the P42 project continues to accumulate.

Since an initial report on Flightglobal four years ago, clues about the project have appeared repeatedly on professional networking website LinkedIn.

Last year, a flight control engineer for Parker Aerospace listed the "Gulfstream P42" project on a list of professional experience. Parker developed the fly-by-wire actuation systems for the G650, which was certificated in September 2012.

More recently, an employee of another supplier listed her work on the "Gulfstream P42 (-1, -2, -3)", suggesting there could be a family of aircraft in development.

Gulfstream has been working behind the scenes to keep its marketing options open for new products. Invoking the designation style launched by the G280 midsize business jet, Gulfstream has trademarked a series of products with a -80 and -90 suffix, ranging from the G180 and G190 to the G880 and G890.

"I think we have been pretty open about the fact that we have a very robust [research and development] programme, and are working on new products and product enhancements," says Steve Cass, vice-president of communications. "We don't make any announcement until we are confident it's in our – and the customers’ – best interests to do so. Until then, everything is just speculative."

Gulfstream certificated the G450 10 years ago as a new version of the GIV-SP, featuring cockpit upgrades developed for the G550, including the Honeywell PlaneView cockpit and an enhanced vision system.

Dassault revealed a direct challenger to the G450 with the Falcon 5X in October 2013. The type offers a wider cabin and about 1,000nm (1,850km) more range. Both factors likely represent design points for any future Gulfstream challenger.

Source: FlightGlobal.com