Narrative:

Approximately 10 minutes after departing; some visible fumes began appearing inside the airplane. The fumes had a smell indicating that they were coming from a hydraulic fluid source. Upon selecting cabin air vent all visible fumes disappeared. I elected to not declare an emergency but to land at the nearest airport. All systems operated normally prior to landing. Upon landing the brakes were ineffective. The airplane crossed the end of the runway at approximately 15 KTS and came to a stop in a grass/dirt overrun. After engine shutdown airport personnel moved the airplane to a nearby taxiway. There was no damage to the runway; approach lights or to the airplane. All; ATC; tower and airport personnel were most helpful.

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Original NASA ASRS Text

Title: A C337's pilot detected hydraulic fumes during climb after takeoff. The pilot chose to divert to a nearby airport but after landing the brakes failed causing him to go off the end of the runway. No damage resulted.

Narrative: Approximately 10 minutes after departing; some visible fumes began appearing inside the airplane. The fumes had a smell indicating that they were coming from a hydraulic fluid source. Upon selecting Cabin Air Vent all visible fumes disappeared. I elected to not declare an emergency but to land at the nearest airport. All systems operated normally prior to landing. Upon landing the brakes were ineffective. The airplane crossed the end of the runway at approximately 15 KTS and came to a stop in a grass/dirt overrun. After engine shutdown airport personnel moved the airplane to a nearby taxiway. There was no damage to the runway; approach lights or to the airplane. All; ATC; Tower and Airport Personnel were most helpful.

Data retrieved from NASA's ASRS site as of April 2012 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.