N56258Piper PA-28R-200 · 1973

On October 30, 2019, about 1032 eastern daylight time, a Piper PA-28R, N56258, was destroyed when it was involved in an accident near Atlanta, Georgia. The commercial pilot and passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

According to air traffic control communications and radar data provided by the Federal Aviation Administration (FAA), the pilot established contact with the ground controller at PDK and advised that he had received the current weather observation, which included variable wind at 6 knots, 6 miles visibility in mist, and an overcast ceiling at 400 ft above ground level. The pilot received an instrument flight rules (IFR) release with instructions to fly a heading of 090° after takeoff.

The pilot contacted the departure controller as he was climbing through 2,000 ft mean sea level (msl) after takeoff and stated that he was turning right to a heading of 090°. The controller instructed him to climb to 5,000 ft msl and to proceed direct to the Athens (AHN) VORTAC.  The controller also advised of moderate precipitation extending to the east for 10 miles along the route of flight.

The pilot began a right turn, and the controller instructed the pilot to turn left direct AHN, advising the pilot that it appeared that the airplane was heading southbound. The pilot turned east and the controller asked if the flight were showing a route direct to AHN, to which the pilot responded, “we are.” The airplane continued eastbound before again turning southbound. About 3 minutes and 24 seconds after contacting the controller, the pilot was instructed to fly a heading of 090° and the pilot advised that they had “…lost our vacuum gauge.” At that time, the airplane was at 5,075 ft msl at a ground speed of 80 knots and turned to the northeast briefly before it entered a right turn and rapidly descended to 3,800 ft in 17 seconds. The controller instructed the pilot to maintain “wings level” and an altitude of 4,000 ft; the pilot did not respond. There were no additional communications from the pilot and radar contact was lost shortly thereafter. The airplane’s last recorded ground speed was 154 knots.

The pilot held a commercial pilot certificate with ratings for airplane single-engine land, multi-engine land, and instrument airplane. Review of portions of his pilot logs and information provided by the pilot’s family revealed that he had accumulated about 5,088 total hours of flight experience, of which 2,938 hours were in the accident airplane make and model. The logs also indicated that he had logged 19.2 hours of instrument flight experience and six instrument approaches in the 90 days before the accident.

According to the aircraft maintenance log, the most recent annual inspection was conducted on September 17, 2019, at a recorded engine total time of 2,756 hours. The most recent maintenance log entry concerning the vacuum pump was dated May 26, 2003, at a recorded engine total time of 2,164 hours, which stated that the vacuum pump was replaced with a serviceable unit. There were no other entries in the maintenance log pertaining to the vacuum pump.

Atlanta Regional Airport – Falcon Field (FFC), Atlanta/Peachtree City, Georgia, 33 miles south-southwest of the accident site, was the closest site with an upper air sounding. The sounding at 0800 indicated alternating layers of conditional instability and stability from the surface through about 9,500 ft msl. It also identified the possibility of clouds from about 650 ft msl through about 10,000 ft msl.

According to the aircraft maintenance log, the most recent annual inspection was conducted on September 17, 2019, at a recorded engine total time of 2,756 hours. The most recent maintenance log entry concerning the vacuum pump was dated May 26, 2003, at a recorded engine total time of 2,164 hours, which stated that the vacuum pump was replaced with a serviceable unit. There were no other entries in the maintenance log pertaining to the vacuum pump.

The airplane impacted a residential apartment building 1.5 miles southeast of the departure airport. The engine was located on the first floor, while the fuselage and cockpit remained outside of the residence. The left main gear and sections of the left wing flap were located on the second floor of the adjacent apartment. The debris field was about 790 ft in length on a magnetic heading of about 270°. A portion of the right wingtip was located on the roof of another residential building. Within the debris field was a portion of the left wingtip, right aileron, horizontal stabilizer, and vertical stabilizer, with the rudder attached by one hinge.

Flight control continuity was confirmed from the cockpit controls to each respective flight control surface through control cable separations consistent with overload failure or cuts made by recovery personnel. All major components of the airplane were located along the debris path except the left aileron. The right wing spar was located near the fuselage and remained attached to the wing box. The outboard portion of the right wing was separated chordwise at the main spar splice joint and the fractures were consistent with overload. The left wing spar inboard attach flanges were located at the accident site; a small section of the wing box, which had separated from the main wreckage, revealed a fracture of the lower spar cap that occurred on the outboard pair of attach bolts. The fracture surface was clean and smooth with no apparent indications of fatigue progression and exhibited damage signatures consistent with impact. The outboard section of the left wing was separated chordwise at the main spar splice joint and the fractures were consistent with overload and was located on the ground near the entrance gate to the apartment complex. Sections of the empennage separated from the airframe before impact, were located along the debris path, and exhibited signatures consistent with overstress failures.

The cockpit was impact damaged and several flight instruments were destroyed. The vertical speed indicator, altimeter, and turn coordinator were located within the wreckage. The electric turn coordinator was disassembled, and the gyro and gyro housing did not exhibit rotational scoring.

The engine remained attached to its mounts and the firewall. The crankshaft was rotated by turning the propeller and crankshaft continuity to the accessory gears and to the valve train was confirmed. Compression and suction were observed from all four cylinders. The interiors of all four cylinders were examined using a lighted borescope and displayed no anomalies. The vacuum pump remained attached to the engine and was removed for examination. The intake and exhaust fittings were impact separated. The pump was partially disassembled. The carbon rotor was fragmented, the carbon vanes were intact, and the composite drive assembly was fractured.

One of the three propeller blades was broken at the base of the propeller hub. All of the propeller blades exhibited rotational scoring and impact marks throughout the span of the blades.

Spatial Disorientation

The FAA Pilot's Handbook of Aeronautical Knowledge stated that,

Under normal flight conditions, when there is a visual reference to the horizon and ground, the sensory system in the inner ear helps to identify the pitch, roll, and yaw movements of the airplane. When visual contact with the horizon is lost, the vestibular system becomes unreliable. Without visual references outside the airplane, there are many situations where combinations of normal motions and forces can create convincing illusions that are difficult to overcome…unless a pilot has many hours of training in instrument flight, flight in reduced visibility or at night when the horizon is not visible should be avoided.

The FAA Airplane Flying Handbook (FAA-H-8083-3) described some hazards associated with flying when visual references, such as the ground or horizon, are obscured:

The vestibular sense (motion sensing by the inner ear) in particular tends to confuse the pilot. Because of inertia, the sensory areas of the inner ear cannot detect slight changes in the attitude of the airplane, nor can they accurately sense attitude changes that occur at a uniform rate over a period of time. On the other hand, false sensations are often generated; leading the pilot to believe the attitude of the airplane has changed when in fact, it has not. These false sensations result in the pilot experiencing spatial disorientation.

The FAA Instrument Flying Handbook, FAA-H-8083-15B, Chapter 11, states:

Many small aircraft are not equipped with a warning system for vacuum failure; therefore, the pilot should monitor the system’s vacuum/pressure gauge. This can be a hazardous situation with the potential to lead the unsuspecting pilot into a dangerous unusual attitude that would require a partial panel recovery. It is important that pilots practice instrument flight without reference to the attitude and heading indicators in preparation for such a failure.