Accident Sequence
The pilot executed a VOR approach to a 3,378-foot-long, 0.7 percent upsloping runway. The runway became visible at the visual descent point. The airplane was landed on the wet runway with full flaps, touching down approximately 1,500 feet from the approach end at a speed between 80 and 85 mph. After touchdown, the pilot announced to the passenger that there were no brakes and retracted the flaps. The pilot again announced the absence of brakes, and the airplane did not begin to slow until the flaps were retracted. The airplane traveled off the end of the runway, initiating a left skid that caused the right main landing gear to collapse.
Runway Condition
The runway had been sealed with black paint sealer, which the pilot described as very slick when wet and considerably more so than asphalt. The runway had been crack sealed and a coal-tar sealer/rejuvenator was applied before the accident date. Following the treatment, wet friction tests on treated and untreated areas revealed that the treated area experienced a loss of 0.05 to 0.08 Mu (friction coefficient value) compared to the untreated area. However, the total treated area had an average Mu of 0.72, which matches the typical Mu value for new design or runway construction. No one from the airport director's staff was aware of any problems associated with the runway crack sealing or seal coating.
Tire Examination
Examination of the main landing gear tires by the Federal Aviation Administration (FAA) revealed that the damage was consistent with hydroplaning. Tread reversal was evident, particularly on the right main tire, and both tires had a section approximately 10 inches long across the entire width where tread separation was evident.
Aircraft Performance Considerations
The Aeronautical Information Manual (AIM) cautions that descent from the MDA at the missed approach point may be inadvisable or impossible on a nonprecision approach, even if current weather conditions meet the published ceiling and visibility. The aircraft's speed, height above the runway, descent rate, and runway length need to be considered to determine if a safe landing can be accomplished. The performance chart in the airplane owner's manual indicates a ground roll distance of 720 feet and a total distance over a 50-foot obstacle of 1,301 feet. The chart does not specify distance to add when landing on a wet runway or distance to subtract due to an upsloping runway.