Board Thread:Questions and Answers/@comment-112.208.10.35-20140612122332/@comment-24739965-20140612141237

It's considered a good way to earn credits and research. Using 3 fuel in a forced sortie will grant you 3.5x the credits and also the research towards your aircraft and weaponry.

Also, if possible, it will grant you 3 random drops. (Limited - Red Containers)