CHI05FA049

The twin-engine airplane was substantially damaged during an in-flight collision with terrain following a loss of control in the airport traffic pattern. Approximately 20 minutes prior to the accident the pilot transmitted: "I've got single engine problems here mayday mayday." Radar track data depicted the aircraft established on a northwest course at 3,500 feet mean sea level. At the time the pilot reported the engine failure, track data showed the aircraft entered a descending left turn, losing 1,000 feet and reaching a south heading 24 seconds later. The pilot regained control of the aircraft and air traffic control provided guidance to the destination airport, which was the nearest airport. The pilot subsequently established the aircraft on approach to the airport. The pilot stated that he was going to circle the airport to the left and hand pump the gear down. The aircraft impacted terrain approximately one-quarter mile south of the runway in the side yard of a residence. The residence was located adjacent to airport property. A line of trees about 40 feet in height was located approximately 19 feet west of the accident site. No evidence of a tree strike was observed. The airplane came to rest resting on the nose and the wings. The empennage was oriented vertically, approximately 65 degrees relative to the terrain. The landing gear was extended. Examination of the left engine revealed a separation of the No. 4 cylinder head. The cylinder head had separated between the second and third cooling fin. Metallurgical examination revealed that the fracture was consistent fatigue cracking. Examination of the left propeller and propeller governor did not reveal any anomalies preventing normal operation of the feathering mechanism. Observations during the left propeller teardown were consistent with the propeller not being in the feathered position at the time of the accident. Maintenance records indicated that approximately 345 hours had accumulated on both engines since overhaul. No other anomalies were observed. According to the aircraft manufacturer's documentation, the accident aircraft hydraulic system was powered by one engine-driven hydraulic pump mounted on the left engine. Hydraulic pressure was used to control the retractable landing gear and the flaps. In the event the left engine loses power the hydraulic pump is not powered and emergency gear extension must be used.

History of flight

On December 28, 2004, at 1135 central standard time, a Piper PA-23-250 (Aztec), N5398M, piloted by a commercial pilot, was substantially damaged during an in-flight collision with terrain at the Gogebic-Iron County Airport (IWD), Ironwood, Michigan. The pilot had reported an engine problem about 20 minutes before the accident while en route to IWD. The personal flight was operating under the provisions of 14 CFR Part 91. The flight was on an instrument flight rules (IFR) flight plan until the pilot canceled IFR on approach to IWD and proceeded under visual flight rules (VFR). Visual meteorological conditions prevailed at IWD. The pilot and four passengers sustained fatal injuries. The flight departed Menominee-Marinette Twin County Airport (MNM), Menominee, Michigan, about 1010.

An individual representing the accident aircraft contacted Green Bay Automated Flight Service Station (AFSS) at 0814 and obtained a pre-flight weather briefing from MNM to IWD. The pilot called Green Bay AFSS again at 0903 and requested an updated weather briefing. At the conclusion of that briefing the pilot filed an IFR flight plan from MNM to IWD.

The Federal Aviation Administration (FAA) provided transcripts of air traffic control (ATC) transmissions with the accident aircraft and radar track data for the flight. Radar track data was processed and plotted by the NTSB. The transcripts and plot of the radar track data are included with the docket information associated with the accident file.

The pilot established contact with Minneapolis Air Route Traffic Control Center (ARTCC) at 1021. The flight was approximately 10 nautical miles (nm) northwest of MNM and climbing through 5,000 feet mean sea level (msl) at the time. The flight climbed to 8,000 feet msl en route to IWD. Communications were routine during this portion of the flight. The pilot was informed that he could expect radar vectors for the Instrument Landing System (ILS) approach to runway 27 at IWD

At 1104, ATC instructed the flight to descend at pilot's discretion and maintain 3,500 feet msl. The pilot acknowledged this clearance.

At 1114:58 (HHMM:SS) the pilot transmitted: "I've got single engine problems here mayday mayday." The controller replied that the closest airport was IWD, the intended destination, and advised a heading of 310 degrees from the aircraft's present position.

At 1119:36 the controller instructed the pilot to turn left to 290 degrees to intercept the localizer on the ILS approach. Twenty-seven seconds later the pilot inquired about the aircraft's heading. The controller replied "you just took a hard left again on that twenty degree turn" and provided a 310-degree heading for the localizer intercept. The pilot stated that he had a "vacuum failure," however, he noted that he was able to maintain a heading. The aircraft subsequently descended below the level of radar coverage at 1120:35.

The pilot reported intercepting the ILS localizer at 1122:04. The pilot also stated, "[I] am single engine and one propeller feathered." At 1127:07, the pilot reported that the runway was in sight. At 1128:00, he reported a "complete loss of hydraulics" to the center controller. The pilot added that he was planning to circle to the left and hand pump the landing gear down. No further transmissions were received from the accident aircraft.

The plot of radar track data for the accident flight depicted the airplane approaching IWD from the southeast. The plot showed the airplane on a northwest ground track passing 6,700 feet msl at 1106:45 and descending until it reached 3,500 feet msl at 1113:46.

At 1114:58, when the pilot initially indicated that he had an engine problem, the radar track indicated that the aircraft was at 3,500 feet msl on an approximate magnetic course of 317 degrees. The aircraft then entered a descending left turn, reaching an altitude of 2,500 feet msl on a 169-degree magnetic course at 1115:22, 24 seconds later. The calculated average descent rate during this time frame was 2,500 feet-per-minute. The calculated average rate of course change during this time was approximately 7 degrees-per-second. A standard rate turn is defined at 3 degrees-per-second.

The track data indicated that the aircraft then entered a climbing right turn, reaching 3,500 feet msl at 1118:10 on an approximate course of 316 degrees. The aircraft subsequently turned left and descended again. Final radar contact was at 1120:35, 10.8 nm east of IWD at 2,400 feet msl.

The accident site was located in the side yard of a residence south of the IWD airport. The owner was home at the time. He reported hearing a loud noise and looked out a window to investigate. When he saw the accident site he contacted the sheriff's department.

Personnel information

The pilot held a commercial pilot certificate with airplane single and multi-engine land and instrument airplane ratings. He also held a flight instructor certificate with an airplane single-engine rating and a ground instructor certificate with advanced and instrument ratings.

The pilot was issued a second class airman medical certificate on October 9, 2004, with a restriction that corrective lenses must be worn.

The pilot's logbook was reviewed. The last logged flight was on November 30, 2004. According to the logbook, the pilot had accumulated 950.4 hours total flight time. He had logged 313.7 hours in multi-engine airplanes, with 11.5 hours logged within the previous 90 days. The pilot's most recent flight review was completed on February 26, 2003.

Within the previous 6 months, the pilot had logged 8.0 hours actual instrument flight time and 5.7 hours simulated instrument flight time. He had logged 20 approaches on flights where actual or simulated instrument flight time was also noted. An additional 24 approaches were logged without any corresponding instrument time for the particular flight.

Aircraft information

The accident airplane was a twin-engine 1977 Piper PA-23-250 Aztec, serial number 27-7754135. The airplane was a six-place, low-wing configuration with retractable tricycle landing gear. The airplane was powered by Lycoming IO-540-C4B5 six-cylinder, fuel-injected, reciprocating engines. Each engine was rated at 250 horsepower.

The engines provided power through Hartzell HC-E2YK-2RBS two-bladed propeller assemblies. The propellers were a hydraulically operated, constant speed design with feathering capability. The propeller blades were moved to lower pitch settings by oil pressure from the propeller governor. The blades were moved to a higher pitch setting by spring and air charge in the hub.

The maintenance logbooks were reviewed. The most recent annual inspection was completed on December 11, 2004, at a total airframe time of 7,210.5 hours. The engine and propeller logbooks noted a recording hour meter of 41.9 hours at that inspection. The hour meter read 48.6 hours at the accident site, indicating 6.7 hours had accumulated since the annual inspection.

The right engine assembly, serial number RL-9402-48, was overhauled on April 24, 1997, and installed on the accident aircraft on December 7, 1997. The logbook noted that 6 "CermiNil" remanufactured cylinders had been installed on the engine. At the time of the last annual inspection, the engine had accumulated 343.8 hours since overhaul. Total time for the engine was not noted.

The left engine assembly, serial number RL-11740-48, was overhauled on April 24, 1997, and installed on the accident aircraft on December 7, 1997. According to the logbook, 6 "CermiNil" remanufactured cylinders were also installed on this engine during the overhaul. Time since overhaul was 343.8 hours and total engine time was not noted in the log.

Meteorological information

The IWD Automated Weather Observing System (AWOS) recorded at 1135: Wind from 260 degrees at 12 knots; visibility 5 stat