Photo © Frank C. Duarte Jr.
Photo © Fred Seggie - WorldAirImages
The best I've found from the RR web site is,
Rolls-Royce buys flying test bed for future engine developments
13 June 2005
Rolls-Royce is converting a Boeing 747-200 to serve as a flying test bed for future engine development programmes.
The first engine to be tested on the aircraft, in mid 2007, will be the Trent 1000, currently being developed as launch engine for the Boeing 787 Dreamliner.
The RB211-524C2-powered aircraft, acquired by Rolls-Royce from Air Atlanta Icelandic, is now in Texas, where it will be adapted by airframe integration specialists, L-3 Communications Integrated Systems, and will be based at the company's Waco facilities. It is currently being re-registered by Rolls-Royce as N787RR.
Clive Barton, Programme Manager, Trent 1000 Flying Test Bed, said: "Having our own aircraft gives Rolls-Royce total flexibility in the way future flight test programmes are planned. The Boeing 747 is an ideal test platform, because it can accommodate a wide range of engine sizes and thrusts which may be involved in future developments."
Airborne testing for all four previous versions of the Trent has been carried out using flying test beds owned by Airbus or Boeing.
The first Trent 1000 ran for the first time exactly on schedule on 14th February 2006. It will take to the skies on a Rolls-Royce Boeing 747 flying test bed in the first quarter of 2007 and, following certification by the airworthiness authorities, it will power the 787's first flight in mid-2007.
Here's a pic of what it should look like,