The Boeing Fuel Cell Demonstrator Airplane 2007-01-3906

In an effort to develop environmentally friendly technologies for aerospace applications, Boeing researchers in Madrid, Spain, and industry partners throughout Europe plan to conduct experimental flight tests this year of a manned airplane powered only by a fuel cell and lightweight batteries. The main objective of this project is to demonstrate a straight level manned flight with fuel cells as the only power source.

The airplane is a modified motorglider with a maximum take off weight (MTOW) of 770 kg, a wing span of 16.3 meters and a maximum L/D ratio of 27. The original engine of the motorglider has been replaced by a hybrid power system, which feeds a brushless DC electrical motor that rotates a variable pitch propeller. The hybrid fuel cell/battery propulsion system combines lithium-ion batteries with a proton exchange membrane fuel cell, which runs on compressed hydrogen gas as fuel and pressurized air as oxidant. The fuel cell system is the main power source and supplies sufficient electrical power for level flight. For take off and climb, the airplane's batteries cut in to provide an additional boost. Flight tests are scheduled for later on in 2007 but much remains to be accomplished before then.