NTSB Factual Report

HISTORY OF FLIGHT

On November 30, 1996, at 1030 eastern standard time, an Aero Commander 681, N9129N, was destroyed when it collided with power lines and terrain while on an instrument approach at Mansfield Lahm Airport, Mansfield, Ohio. The certificated private pilot was fatally injured. Instrument meteorological conditions prevailed and an instrument flight rules (IFR) flight plan was filed. The personal flight was conducted under 14 CFR Part 91, and originated at Greene County Airport in Dayton, Ohio, at 0915, destined for Mansfield, Ohio.

The pilot had planned to pick up his family at Mansfield, and return the same day. According to Air Traffic Control (ATC) records, at 0948, the pilot radioed Dayton Approach Control after departing Greene County Airport, and received an IFR clearance to Mansfield Airport. The flight proceeded uneventful for the next 57 minutes.

At 1012, the pilot was cleared to descend to 3,000 feet. At 1017, the pilot was issued a clearance for the VOR runway 14 approach. At 1018, the pilot contacted the Mansfield tower, and was cleared to land on runway 14.

At 1019, the pilot advised the tower that he was on the wrong course, and requested vectors for another approach. The tower coordinated with approach for the tower to vector the pilot for another approach. At 1023, the tower cleared the pilot for a second approach. At 1025, the pilot was again cleared to land on runway 14. At 1026, the pilot advised the tower that he did not see the airport, and requested a third approach. The tower advised the pilot that he was coming as far as the VOR, and the airport was four miles beyond the VOR. The pilot was then given vectors for a third approach.

At 1030:27, the tower advised the pilot that he was over the VOR, and the pilot acknowledged that he had the runway in sight. At 1030:36, the pilot was issued the wind and a landing clearance, which the pilot acknowledged. The controller reported that after he issued the landing information, he could see the airplane from the tower. He said the pilot, "...descended quickly and appeared very low. His mode C indicated 1,400 on the brite scope. I observed the landing light of the airplane bobbing up and down on final. I then observed the aircraft fly up in the air and flip into the ground... ."

A witness who was hunting in the area at the time of the accident said, "...we heard the plane coming. I turned around and looked and the plane was low. It looked like the pilot tried to pull the plane up, and the high voltage wire was already around the right wing. I could hear what sounded like the propeller hitting the wire. After that the pilot was still trying to pull the plane up... ."

The airplane struck power lines about 2 miles northeast of the approach end of runway 14, and descended into a soybean field. The accident occurred during the hours of daylight about 40 degrees, 50 minutes North latitude, and 82 degrees, 32 minutes West longitude.

PILOT INFORMATION

The pilot held a Private Pilot Certificate with ratings for airplane single and multi-engine land, and instrument airplane. A review of his log book revealed that he had accumulated over 587 hours of total flight experience. He had logged more than 155 hours actual instrument hours, which included 8 hours within the last 90 days. The last recorded actual instrument experience was October 23, 1996. His most recent FAA Third Class Medical Certificate was issued on September 11, 1995, with limitations to wear corrective lenses.

METEOROLOGICAL CONDITIONS

At 1016, Mansfield Lahm Municipal Airport, Mansfield, Ohio, reported the following observation:

Sky condition, ceiling 500 overcast; visibility, 2 1/2 miles in mist and fog; temperature, 43 degrees Fahrenheit (F); dew point, 43 degrees F; winds from 170 degrees at 14 knots; and altimeter, 29.92 inches Hg.

WRECKAGE AND IMPACT INFORMATION

The airplane wreckage was examined at the accident site on December 1, 1996. The wreckage came to rest within the dimensions of the airplane, oriented on a magnetic heading of 200 degrees. All major components of the airplane were accounted for at the scene.

Examination of the accident site revealed that the airplane struck power lines about 2 miles from the approach end of runway 14, then collided with terrain. The power lines were 1,382 feet above mean sea level (MSL), and sections of cable was found wrapped around the right wing.

The right wing remained intact, except for the right aileron which had separated. On the right forward side of the wreckage in the mud, were ground imprints, similar to the size and shape of the right wing.

One of the propeller blades from the right engine separated, and was located forward of the right engine. The right engine remained attached to the wing, but was twisted. One of the left propeller blades was separated, and was not found. Examination of the remaining blades for the left and right engine revealed evidence of cuts on the propeller de-icing boots. The cuts were similar in size and shape to the static line cable. The tips of the two propeller blades for the left engine were separated.

The tail section including the vertical stabilizer, rudder, left and right horizontal stabilizer, and left and right elevator was intact. The forward fuselage and flight instruments were destroyed. Cable continuity could not be determined in the field due to the field being soft and muddy. The airplane was moved to a hangar, and further examined on December 12 and 13 at the Mansfield Airport.

The right wing was crushed chordwise and there were several chordwise cuts similar in size and shape to the static cable. A section of cable remained lodged in the wing. The left wing was intact. Both left and right ailerons were separated from their respective wings. The push/pull rods were attached to the ailerons.

The elevator trim tabs and the rudder trim tab were in the neutral position. The flap hydraulic cylinder rod was extended about 4 inches. According to the Twin Commander investigator, this corresponded to full flap down position.

The nosegear was damaged as well as the left main landing gear. The right main gear was in the down and locked position. The landing gear selector was in the down and locked position.

Flight control cable continuity was confirmed from the surfaces to the cabin area.

Examination of the wreckage revealed no pre-impact failure of the airplane or engine.

TESTS AND RESEARCH

Both engines were removed and sent to Allied Signal Aerospace, Phoenix, Arizona, where they were examined on March 11 and 12, 1997, under the supervision of the National Transportation Safety Board. The examination revealed that both engines exhibited rotational damage at the time of impact. No pre-existing conditions were found on either engine which would have prevented normal operation.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy and toxicological testing of the pilot was conducted by Dr. Keith N. Norton, M.D. Medical Examiner of the Franklin County, Columbus, Ohio.

Toxicological testing was conducted by the FAA Toxicology Accident Research Laboratory, Oklahoma City, Oklahoma, on March 5, 1997.

ADDITIONAL INFORMATION

According to the Instrument Approach Procedures Chart for the Mansfield Lahm Municipal Airport, the airport elevation was 1,297 feet MSL, and the minimum descent altitude (MDA) for the VOR Approach was 1,620 feet MSL. An operational test of the VOR approach was conducted, and it operated satisfactory.

The aircraft wreckage was released on March 13, 1997, to Rick Krueger, a representative of the owner's insurance company.

NTSB Probable Cause

the pilot's early descent below the minimum descent altitude (MDA), while preparing to land from an instrument approach, and his failure to maintain adequate altitude and clearance from obstruction(s).