This paper evaluates fuel cell technologies for multifunctional use in aircraft. In addition to electrical system efficiency, both water production and the availability of gases for tank inerting must be considered for this specific application. A multistep process analysis methodology is implemented here to select the most appropriate fuel cell system configuration. After introducing specifications for avionic fuel cell systems, theoretical aspects are discussed. This is followed by a stepwise process analysis introducing relevant parameters with the aid of statistical tools. A strategic evaluation then considers fuel issues. The evaluation as a whole shows that hydrogen-based systems are more advantageous in terms of achieving high efficiencies with high net water production rates. Considering volume and mass balances, this technology is preferable for short-range missions. The evaluation also shows that kerosene-based HT-PEFC systems are a better choice for medium- to long-range missions. (C) 2013 Elsevier Ltd. All rights reserved.