07/31/2011. The fourth prototype was produced as an A380-841, fitted with Rolls-Royce Trent 900 series engines. Later it was fitted with Alliance GP7200 series engines and redesignated A380-861. Total firm orders and deliveries for the A380 stand at 236 and 51 respectively.

The Airbus nomenclature for types and engines is as follows:
First digit indicates the version.
Second digit indicates engine manufacturer:

0 for General Electric
1 for CFM International
2 for Pratt and Whitney
3 for International Aero Engines
4 for Rolls-Royce
6 for Engine Alliance

The third digit indicates the engine type per manufacturer:

1 for Rolls-Royce Trent 970-84 or 970B-84
2 for Rolls-Royce Trent 972-84 or 972B-84
1 for Engine Allian GP 7270

In case of the pictured aircraft the sub-versions 841 and 861 indicate series 800 aircraft with Rolls-Royce Trent 970-84 and Engine Alliance GP7270 engines respectively.

The development of engines and spreading of development costs is leading to more and more collaboration in the engine manufacturers world. In the engine manufacturers list for Airbus there are three:

CFM International is a joint venture between General Electric (USA) and SNECMA (Société Nationale d'Étude et de Construction de Moteurs d'Aviation, National Company for the Design and Construction of Aviation Engines) (France). The CFM in the company name (and its product line CFM56) is not an acronym, but a combination of the two parent companies' pre-joint venture engine designations: General Electric's CF6 and SNECMA's M56.

International Aero Engines is a joint venture of Pratt & Whitney (USA), Rolls-Royce (UK), Japanese Aero Engine Corporation (Japan) and MTU (Motoren und Turbinen Union, Engine and Turbine Union) Aero Engines (Germany), while the Engine Alliance is a joint venture between General Electric and Pratt and Whitney.