A Cessna 172 Was Substantially Damaged When It Collided With An Aero Commander 500 While Landing

Location: Atlanta, GA Accident Number: ERA21LA056
Date & Time: November 25, 2020, 00:09 Local Registration: N8125U (A1); N777CM (A2)
Aircraft: Cessna 172 (A1); Aero Commander 500 (A2) Injuries: 1 None (A1); 1 None (A2)
Flight Conducted Under: Part 91: General aviation - Personal (A1); Part 135: Air taxi & commuter - Nonscheduled (A2)

On November 25, 2020, at 0009 eastern standard time, a Cessna 172, N8125U, was substantially damaged when it collided with an Aero Commander 500, N777CM, while landing at Dekalb-Peachtree Airport (PDK), Atlanta, Georgia. The Aero Commander sustained minor damage. The pilots of both airplanes were not injured. The Cessna was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The Aero Commander was operated as a Title 14 CFR Part 135 flight.

According to the pilot of the Cessna, PDK was his home airport. While en route, he deviated around some fog, which delayed his planned arrival time until after the control tower had closed. Upon arrival near PDK, he listened to the airport terminal information service (ATIS) recording and recalled that he “wrote down the radio channels and headed in, thinking how much (he) hated being without air traffic control.” As he neared the airport, he activated the pilot-controlled lighting, and the runway lights “lit up.” He saw green lights at the approach end of what he believed to be runway 21R, and stated that these lights indicated the direction he was supposed to land on the active runway. He then “switched radio channels” and made “routine calls.” He did not hear any radio transmissions advising of other traffic operating at or near PDK. He recalled that the airplane’s landing lights and navigation lights were on while on approach. During landing, at an altitude of about 10-15 ft above the runway, about 200 ft past the runway numbers, and at a speed of about 65 knots, he saw a “tiny white light approaching extremely fast.” About 3 seconds later, he heard a “bang” and the “plane pitched hard to starboard.” He maneuvered the airplane back to the runway centerline and landed. He stated that he exited the runway at taxiway F, did not make any further radio calls, and taxied to his parking spot. An airport security guard then informed him that he had collided with another airplane.

According to the pilot of the Aero Commander, he opted to land on runway 3R “because other aircraft were landing on 3R.” He followed an EMS helicopter that was landing on runway 3R. He entered the right downwind leg of the traffic pattern and “made the appropriate CTAF [common traffic advisory frequency] calls on frequency 120.9.” He entered the right base leg of the traffic pattern and then turned onto a 1/2-mile final approach leg for runway 3R, “announcing each leg [on the CTAF frequency].” He reported that he typically does not adjust the intensity of the runway lights when landing at PDK, and he noticed that the light intensity increased while on approach. After landing, he saw “some lights” though he was initially not sure what they were. He subsequently “realized it was an oncoming aircraft landing on runway 21L.” He indicated both airplanes swerved, and the right wingtip of the Cessna contacted the right outboard wing of the Aero Commander.

A review of preliminary Federal Aviation Administration (FAA) tracking data revealed that the Cessna approached the airport from the northeast and flew a straight-in approach to runway 21L. A review of FAA recordings of the CTAF frequency 120.9 revealed that at about 0005, the pilot of the Aero Commander initially announced that he was on the left downwind of the traffic pattern for runway 21L. About 2 minutes later, N649AE, an EMS helicopter, advised that he was on a modified base leg of the traffic pattern for runway 3R. The pilot of the Aero Commander then advised that he was on final approach for runway 21L. N649AE then advised that he had the Aero Commander in sight, acknowledged the potential conflict, and offered to approach the “shorter runway” (3L) instead. The pilot of the Aero Commander acknowledged, and informed N649AE that he would instead go-around, and enter the right downwind leg of the traffic pattern for runway 3R. The pilot of the Aero Commander subsequently transmitted his position as he entered the downwind leg of the traffic pattern and again as he made the turn onto the final approach leg. Just after his turn to final, N649AE announced that he was clear of the runway and hovering over the ramp. The Aero Commander pilot acknowledged and advised that he had N649AE in sight. FAA tracking data showed that at the time the Aero Commander pilot advised that the had N649AE in sight, the Cessna was on final approach, about 1/2-mile from the displaced threshold of runway 21L. The recording did not include any radio calls from the Cessna pilot.

Examination of both airplanes by an FAA inspector revealed that the Cessna sustained substantial damage to the right wing tip, including the outermost wing rib, and bending of the right aileron. Postaccident testing of all lights (with the exception of the right wing tip navigation light, which was separated from the wing) revealed no anomalies. Testing of the single communication radio revealed successful transmission and reception. Examination of the Aero Commander revealed minor scrapes/paint transfer to the underside of the right wing near the outboard edge of the wing flap, and minor damage to the right wing flap.

According to the airport/facility directory, the CTAF frequency at PDK is published as 120.9, which is the same frequency for the air traffic control tower when it is operating. When the tower is closed, the high intensity runway lights (along the runway edges) for runway 3R/21L are turned on and preset to medium intensity. The pilot controlled lighting system uses a separate radio frequency, 120.0, which can be used to: 1) increase the intensity of the runway edge lights, 2) activate the runway 21L approach lights (Medium Intensity Approach Lighting System with Sequenced Flashers or MALSF), which include green lights that mark the runway threshold, and 3) activate the taxiway lights. The green threshold lights, oriented transverse to the runway centerline, denote the location of the (displaced) runway threshold and are not an indication of the “active runway” in use.

FMI: www.ntsb.gov