On June 28, 2007, about 1815 Alaska daylight time, a Piper PA-31 airplane, N3535F, sustained substantial damage when it departed the runway surface and collided with a ditch during the landing roll at the Ralph Wien Memorial Airport, Kotzebue, Alaska. The airplane was being operated as a visual flight rules (VFR) cross-country positioning flight under Title 14, CFR Part 91, when the accident occurred. The airplane was operated by Frontier Flying Service Inc., Fairbanks, Alaska. The airline transport certificated pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed, and VFR company flight following procedures were in effect. The flight originated at the Selawik Airport, Selawik, Alaska, about 1745. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on June 28, the airport manager at the Kotzebue Airport reported that the accident airplane was landing on runway 26, and appeared to start a right turn at taxiway E, into the ramp area. The airplane produced a skid mark on the runway surface that overshot taxiway E, and then departed off the right edge of the runway into a ditch. The airplane received damage to the propellers, landing gear, and fuselage. During a telephone conversation with the NTSB IIC, on July 2, the pilot reported that he had flown several flights from Kotzebue to Selawik and back on the day of the accident. He said that when preparing to leave the parking area at Selawik during his second flight of the day, the airplane's brakes appeared to be locked, but the parking brake was not set. He was able to free the airplane by manipulating the parking brake several times, applying engine power, and by moving the nose gear steering via the rudder pedals several times. The airplane brakes released, and he had no further problems until the last landing of the day at Kotzebue, which was his third flight of the day. The pilot said he did not report the brake problem to the operator. The pilot said he touched down on the dry surface of runway 26, about 1/2 way from the threshold and taxiway E, and as soon as all three landing gear tires were on the ground, the airplane began a gradual right turn. He said he applied left brake and left rudder, but he could only change the ultimate location of the departure from the runway by a small amount. On July 2, the assistant director of maintenance for the operator reported that the airplane received structural damage to the fuselage bulkhead at the front of the windshield, and damage to the aft spar of each wing at the landing gear attach points. The Kotzebue Airport is equipped with a hard-surfaced runway on a 080 to 260 degree magnetic orientation, and a gravel-surfaced runway on a 170 to 350 degree magnetic orientation. Runway 26 is 5,900 feet long, and 150 feet wide. Taxiway E, which has a diagonal right turn into the airport ramp area, is 3,431 feet from the threshold of runway 26. At 1824, a special weather observation at the Kotzebue Airport was reporting, in part: Wind, 160 degrees (true) at 13 knots; visibility, 10 statute miles; clouds and sky condition, 2,500 feet scattered, 4,300 feet scattered, 8,500 feet overcast; temperature, 57 degrees F; dew point, 50 degrees F; altimeter, 29.82 inHg. The airplane is equipped with hydraulic brakes, and a hydraulic parking brake valve. The parking brake valve is activated by a cable between the valve and the parking brake handle. Application of the airplane's brakes via pedal pressure, and then pulling out on the parking brake handle, sets the parking brake. After recovery from the ditch, a Federal Aviation Administration (FAA) inspector from the Fairbanks Flight Standards District Office (FSDO), Fairbanks, Alaska, accompanied by a mechanic from the operator, examined the airplane. Their examination revealed that the parking brake cable was not securely fastened to the airframe by its attaching clamp. This could allow the outer cable housing to move independent of the inner wire attached to the parking brake valve, and could prevent parking brake release. Partial valve activation could hold hydraulic brake pressure on the airplane's brakes, if the brakes were touched during flight.