Narrative:

While taxiing to obtain fuel on a night IFR cross country flight; we had a prop strike. It happened on the south side of a refueling station (the 'mushroom') that had a 100LL sign; which was the type of fuel we were looking for. As we slowly taxied to the refueling station we were turning left to align the airplane with the refueling station fuel hose reels; the starboard main landing gear went down an unmarked drain hole with a metal grate on the bottom [at which time the prop strike occurred]. After shutting off both engines; we disembarked and only then realized the refueling station was for fuel trucks. The refueling station had previously been available for airplanes. There was no signage to indicate for fuel trucks only and not for airplanes.

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Original NASA ASRS Text

Title: The instructor pilot aboard a small twin engine airplane taxied to what he believed to be the aircraft refueling station at HIO and; only after taxiing into a depressed drainage grate and striking the right prop; learned it was intended solely to refuel gas trucks which conducted aircraft refueling on the adjacent ramp.

Narrative: While taxiing to obtain fuel on a night IFR cross country flight; we had a prop strike. It happened on the south side of a refueling station (the 'mushroom') that had a 100LL sign; which was the type of fuel we were looking for. As we slowly taxied to the refueling station we were turning left to align the airplane with the refueling station fuel hose reels; the starboard main landing gear went down an unmarked drain hole with a metal grate on the bottom [at which time the prop strike occurred]. After shutting off both engines; we disembarked and only then realized the refueling station was for fuel trucks. The refueling station had previously been available for airplanes. There was no signage to indicate for fuel trucks only and not for airplanes.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.