The human-powered helicopter team at the University of Maryland made clear progress last week in flying their craft, coming closer to the performance required for a $250,000 prize.

Last July, the university said, its team of student engineers kept their copter aloft for 11.4 seconds.

But an upgraded version of last year’s craft made at least two flights last week that far outstripped last year’s mark.

On June 20, the new copter stayed up for about 35 seconds, and the next day for about 50, Maryland’s engineering school said. Staying up for 60 seconds is one key requirement for the American Helicopter Society’s human-powered helicopter prize.