Amazing demonstration! Hydrogen will shape out to be one of the best transition/long term combustion fuels we have as it's prinary by-product is simply water vapor in addition to the fact that hydrogen can be made using zero-emission energy sources.

In the case of transportation (hydrogen-powered vehicles), it might not be too practical however. Storage of the fuel is a major design considerations. The article was not too clear about the form of hydrogen the aircraft used (gaseous or liquid hydrogen). Liquid hydrogen (LH2) is somewhat practical as it occupies a fairly small volume, but it is cryogenic. A storage tank must be well-insulated as well as contain boiloff bleed valves (very similar design to the fuel tanks on a rocket). High-pressure gaseous hydrogen (GH2) is another option where the fuel is stored as compressed hydrogen gas (upwards to 6000 psi if not higher). Big issue is that you are then contending with hydrogen embrittlement (the hydrogen will quite literally seep into the metal of the pressure vessel and reduce the strength of the metal. This can be prevented through careful choice of material.

Regardless, this is fascenating and a great step forward to making air travel more environmentally friendly. The aforementioned design considerations will be dealt with and hydrogen will be a clean and dependable option to fuel combustion engines with.