HyFish is a small SmartFish powered by a fuel cell. Together with the Institute for Technical Thermodynamics of the German Aerospace Centre (DLR) in Stuttgart we developed a flying experimental vehicle that was run by fuelcell power.

The objective of the project was to demonstrate the effectiveness of fuel cells in a challenging environment. At the same time the construction of the experimental vehicle helped to gain further knowledge in the areas of lightweight construction and packaging of fuel cell systems.

The aircraft was to be constructed based on the concept by Swiss company SmartFish GmbH, because the aircraft design combines volume and usable weight as well as excellent performance.

SmartFish RC prototpye with fuel cell at Hannover Fair 2006

The fuell cell system including the gas tanks and the propulsion system can be seen in the foreground. The flight ready version of the fuel cell system was optimized in tearms of weight and efficiency.

Image of air intakes of HyFish at AOA 25 degrees

Team SmartFish did a lot of CFD analysis for the flight ready version of HyFish. The results from the optimisation of low speed flight characteristics have been directly integrated into the new design of HyFish G2.

Milling of HyFish G2 moulds at TZU

Milling the moulds was a challenging task, since the design of SmartFish is just made out of free form surfaces, but the TZU did a great job.

HyFish Manufacturing

The composite structure for HyFish was done by LTB Borowski. Most parts have been manufactured from glass fiber with a honeycomb sandwich. The resulting structure has a low weight but is still strong enough to carry the fuel cell, the hydrogen tank and all the other components.

Fuel Cell testing at DLR laboratory

In parallel to the design and manufacturing of the aircraft Horizon developed a custom made fuel cell for HyFish. The fuel cell was then tested and qualified at DLR.

X-Ray of HyFish

When all the parts were ready we integrated everything. Everything went well, and soon we have been ready for the first flight.

Preflight Preparations

Finally came the day where HyFish was up and in the air. Click on the picture below when you want to see small movie. Or download the movie here (5 MB).

HyFish in Flight

HyFish has a wingspan of 1m, a total lenght of 1.3m and a weight of 6.1kg. The fuel cell system including electronics and hydrogen tank has a weight of 3kg and an electrical output of 1kW. The propulsion of HyFish is realized using a ducted fan driven by an eletric motor. The energy source to power the electric motor is only the fuel cell. The thrust to weight ratio of the complete aircraft is roughly 1:3. Possible flight time is around 15min when flying full speed, when using less power the flight time will be much longer. The flight performances are fantastic. We have made loopings, rolls, steep dives and climbs.

Compared to conventional RC planes the HyFish is underpowered. But despite that HyFish has shown excellent flight characteristics and performances! Flight speed is up to 200km/h!

When comparing the performance of HyFish with the performance of other fuel cell powered aircraft then you can imagine the potential of the SmartFish concept. Please have a look for a comparison with other fuell cell projects at http://www.horizonfuelcell.com/aerospace.htm.

For more information about HyFish and DLR:

Dr.-Ing. Till Kaz  
Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Technische Thermodynamik 
Tel.: +49 711 6862-426 

A PDF about HyFish can be downloaded here: Download PDF (112 KB)