IAD03FA005

The pilot requested, and was approved for a GPS approach. He was issued an altimeter setting, but did not acknowledge it. Radar data revealed that the airplane passed about 1 mile to the right of an intermediate approach fix, and was nearing the abeam position, about 1/2 mile to the right of the final approach fix. At both positions, the airplane was about 300 feet below the minimum segment altitude. After passing the final approach fix, the controller advised the pilot that radar contact was lost and the pilot acknowledged the transmission. No further transmissions were received from the pilot. The airplane impacted a tower, slightly left of the approach course centerline, at an elevation of about 1,350 feet. The minimum descent altitude along that approach segment was 1,800 feet. The setting found on the altimeter would have placed the airplane about 100 feet lower than it should have been. A witness stated that minutes after the accident, he looked up at the tower to check for damage, and saw that the top of it was "just in the bottom of the clouds." The airplane was certified for IFR operation; however, it was not equipped with an IFR-certified GPS receiver. A personal, hand-held computer with an antenna and integrated GPS receiver was found at the accident site. The software vendor had posted a warning on its website, which stated, "The system is not tested or approved by the FAA or any governmental agency and should not be used as a primary flight instrument."

History of flight

On October 15, 2002, about 1720 eastern daylight time, a Cessna 172N, N6413J, was destroyed during an approach to Mount Sterling-Montgomery County Airport (IOB), Mount Sterling, Kentucky. The certificated private pilot and the passenger were fatally injured. Instrument meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan was filed for the flight that departed Greenwood Municipal Airport (HFY), Greenwood, Indiana, and was conducted under 14 CFR Part 91.

The pilot had been cleared for the Mount Sterling GPS RWY 21 approach. The final four fixes were: FELPO, the intermediate approach fix; ISFUR, the final approach fix; an unnamed step-down fix 2.3 nautical miles from the missed approach point; and RW21, the missed approach point. The inbound course from FELPO through RW21 was 211 degrees magnetic. The minimum descent altitude at FELPO was 3,000 feet above mean sea level (msl). The minimum descent altitude between FELPO and ISFUR was 2,600 feet msl, and between ISFUR and the unnamed step-down fix was 1,800 feet msl. The minimum descent altitude between the unnamed step-down fix and RW21, for the airspeed flown, was 1,460 feet msl.

A review of Air Traffic Control (ATC) voice communications and radar data revealed that, at 1650, the pilot contacted the Lexington Terminal Radar Approach Control, advised that he was in level flight at 5,100 feet, and requested the GPS RWY 21 approach. The controller acknowledged the call, and advised the pilot that the Lexington altimeter setting was 29.85. The pilot did not acknowledge the altimeter setting.

At 1652, the controller cleared the pilot to fly direct to URFAX, an initial approach fix. The pilot then requested, and was subsequently cleared, to fly direct to FELPO.

At 1701, the controller cleared the pilot to descend from 5,000 feet to 3,000 feet. At 1704, the controller asked the pilot to report when he reached FELPO. At 1712, about 1.5 nautical miles from FELPO, the controller cleared the pilot for the approach and advised him to maintain 3,000 feet until established on the approach.

On two occasions during the approach, at 1715, and 1717, the controller advised the pilot of an approved radio frequency change to the Mount Sterling common traffic advisory frequency. Each time, the pilot asked to remain on the approach control frequency, and once stated, "i'd like to stay on this frequency in case we have to go missed and come over there to lexington to do the i-l-s."

A review of radar data revealed that the airplane passed abeam FELPO about 1 nautical mile to the right of the approach course, at 2,700 feet. The airplane then tracked toward the approach course between FELPO and ISFUR, and its altitude fluctuated between 2,500 and 2,300 feet. At 1718, the airplane was almost abeam ISFUR, about 1/2 mile to the right of the approach course, at 2,300 feet. At that time, the controller advised the pilot that radar contact was lost, and the pilot acknowledged the radio call. There were no further communications from the pilot.

The accident occurred during daylight hours, in the vicinity of 38 degrees, 05 minutes north latitude, 83 degrees, 56 minutes west longitude.

Personnel information

The pilot held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. His most recent Federal Aviation Administration (FAA) third-class medical certificate was issued July 16, 2001. On that date he reported 351 total hours of flight experience.

An examination of the pilot's logbook revealed that he had logged 478 total hours of flight experience, 2.6 hours of which were in the Cessna 172. The pilot had also logged 106 hours of instrument flight experience, 52 hours of which were in actual instrument conditions.

The pilot owned a Piper PA-32-260, and due to the fact that it was at a maintenance facility for repairs, he had rented the accident airplane.

In written statement, the certificated flight instructor who performed the checkout of the pilot in the accident airplane the night before the accident flight, reported that the pilot had demonstrated multiple IFR tasks to standard, and described the pilot as "very competent." The instructor also stated that the pilot used a hand-held personal computer with a GPS antenna, and that during the checkout he asked the pilot to turn the computer off because the display was very bright, and it made night eye adaptation difficult.

Aircraft information

The accident airplane was a 1980 Cessna 172N, and at the time of the accident, it had accrued 7,406 hours of operating time. The airplane's most recent annual inspection was completed on September 27, 2002, and it had accrued 34 hours of time since that date. The airplane was certified for IFR operations; however, it was not equipped with an IFR-certified GPS receiver.

Airport information

Mount Sterling Airport runway 21 was 5,002 feet long and 75 feet wide, with a 0.7 percent upslope. The runway touchdown zone elevation was 1,006 feet.

Meteorological information

At 1645, the weather reported at Mount Sterling Airport included a broken ceiling at 500 feet above ground level (agl), a broken cloud layer at 1,600 feet agl, visibility 3 statute miles, temperature 58 degrees Fahrenheit, dew point 53 degrees Fahrenheit, visibility 3 statute miles, altimeter setting of 29.87 inches of mercury. Wind speed and direction were broadcast, but not recorded.

At 1745, the weather reported at Mount Sterling Airport included an overcast ceiling at 500 feet agl, visibility 3 statute miles, temperature 58 degrees Fahrenheit, dew point of 54 degrees Fahrenheit, and an altimeter setting of 29.86 inches of mercury. Wind speed and direction were broadcast, but not recorded.

At 1654, the weather reported at Lexington-Bluegrass Airport (LEX), Lexington, Kentucky, elevation 979 feet, located about 30 nautical miles west of Mount Sterling, included winds from 340 degrees true at 3 knots, rain and mist, a broken ceiling at 300 feet, visibility 1 3/4 statute miles, temperature and dew point 54 degrees Fahrenheit, and an altimeter setting of 29.84 inches of mercury.

A witness, who lived next to the crash site, stated that he became aware of the accident within minutes of its occurrence, and that when he looked up at the tower to check for damage he saw that "the top of the tower was just in the bottom of the clouds or fog."

Aids to navigation

On October 16, 2002, the GPS RWY 21 approach at Mount Sterling was flight-checked by the Federal Aviation Administration. According to the flight inspector's report, the waypoints, approach evaluation, and facility operation were all "satisfactory".

Wreckage and impact information

The wreckage was examined at the accident site on October 16, 2002, and all major components were accounted for at the scene.

The initial point of impact was about 75 feet from the top of a 415-foot orange and white tower that rose to 1,426 feet above mean sea level. The tower was located at 38 degrees, 05.9 minutes north latitude, 83 degrees, 56.7 minutes west longitude, just slightly left of the approach course centerline, about 3 miles northeast of Mount Sterling Airport. Guy wires supported the tower, and two of those wires, on the western side of the tower, were broken and lay on the ground.

Airplane parts and components were scattered beneath the tower and along the wreckage path that was 634 feet long, and oriented in a direction of 217 degrees magnetic. The wreckage path was divided into 1-foot increments, labeled wreckage points (WP).

The outboard section of the left wing, outboard section of the left horizontal stabilizer with elevator attached, and another portion of the left horizontal stabilizer, were found beneath the tower. The pieces were grouped between WP 18 and WP 42, about 45 to 60 feet to the right of the wreckage path centerlin