N811PS

On March 17, 2022, about 1345 eastern daylight time, an experimental, light sport Czech Sport Aircraft Piper Sport airplane, N811PS, was lost from radar and presumed destroyed about 15 nautical miles west of Everglades National Park, Florida. The pilot has not been located and is presumed fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

Federal Aviation Administration (FAA) flight track data showed that the airplane departed The Florida Keys Marathon International Airport (MTH), Marathon, Florida, about 1312. The airplane climbed to a cruise altitude of about 1,450 ft mean sea level (msl) and flew northwest toward Naples Municipal Airport (APF), Naples, Florida. The airplane maintained its altitude, 336° heading, and 125-knot groundspeed until 1323, when it descended and gradually increased airspeed. The track data depicted a rapid climb from 1,200 ft msl to 1,800 ft msl at 1324 while the airplane slowed to 74 knots groundspeed. The airplane then resumed its previous heading and groundspeed at an altitude of about 1,450 ft msl until 1327, when it began a series of erratic heading, altitude, and groundspeed excursions.

The track depicted a brief climb before the airplane descended, accelerated, and completed a 240° turn to the east. During the turn, the altitude varied between 1,600 ft msl and 800 ft msl, and groundspeeds varied between 83 and 143 knots. The airplane then continued in a wide, arcing left turn until it intercepted its original course. Once reestablished on its same approximate course, the airplane assumed a cruise profile about 800 ft msl and 100 knots groundspeed about 1331.

The altitudes varied only slightly between 800 and 900 ft msl, and groundspeed remained about 100 knots until 1343:38, when the airplane’s track ended on a 336° heading at 825 ft msl and 100 knots groundspeed. No further targets were identified, and air traffic control (ATC) records revealed that the airplane never established communication with any ATC facilities after departing MTH. Figures 1 and 2 show flight track information, with the accident flight depicted in green and the previous flight depicted in yellow.

Figure 1. Flight track information

Figure 2. Flight track information

Airplane wreckage and paperwork associated with both the airplane and the pilot were recovered from the surface of the ocean and secured by the U.S. Park Service following the accident.

The airplane was manufactured in 2010. According to the pilot’s family, both the airplane maintenance logs and the pilot’s logbook were likely on board the airplane. Invoices reflecting three consecutive “annual condition inspections” were provided by an aircraft maintenance facility and indicated that the most recent inspection was completed January 19, 2022, at 569.2 total airplane hours. The invoices reflected that, in the 2 years before this inspection, the airplane had flown 31.0 and 24.7 hours, respectively.

The pilot held a private pilot certificate with ratings for airplane single-engine land and instrument airplane. His most recent third-class medical certificate was issued May 20, 2014, and he reported 1,350 total hours of flight experience on that date. The pilot completed the BasicMed course on August 30, 2017.

Review of flight track information for the flight from APF to MTH earlier on the day of the accident revealed similar erratic altitude, heading, and speed excursions as those displayed during the accident flight. The data indicated that the pilot flew a left downwind leg for landing on runway 07 at MTH at an altitude of 200 ft msl. At a point consistent with a left base leg, the airplane completed a 180° turn and flew a right downwind for runway 25 at 200 ft msl, landing opposite the direction of other landing traffic.

Automatic dependent surveillance-broadcast (ADS-B) data showed that the accident airplane landed on runway 25 when a business jet was on short final for landing on runway 07. In written statements, the crew of the business jet advised that the accident airplane cleared the runway before they were required to abort their landing.

The data showed that the accident airplane taxied erratically on the airport surface, with numerous heading changes and course reversals, over a 6-minute span. Ground personnel stated that the pilot did not respond to radio calls and had to be told in person by a lineman that his party was parked at the opposite end of the airport. The airplane also experienced another head-on encounter with the landing business jet while on the taxiway.

Two friends of the pilot were interviewed by telephone, and their versions of events were consistent throughout. The three had agreed to fly their individual airplanes from APF, where they were based, to MTH, have lunch, then fly back to APF. The accident occurred on the return flight. Neither heard the accident pilot over the radio, and they became concerned when they felt his arrival at APF was overdue.

The friends described the departure from APF, their arrival at MTH ahead of the accident pilot, and how his arrival “took longer than expected.” Each was a retired airline pilot, and the tracks of both the accident pilot’s flights were discussed with them. They said that the pilot explained his opposite-direction landing based on his interpretation of the windsock. Each was asked to describe the pilot’s appearance, behavior, and if any of those behaviors concerned him. One responded, “Yes, he didn’t eat his lunch, which was unusual.” The other individual said that the pilot was engaged in their lunch conversation and that he would have acted if he had any concerns. He added, “My wife said he seemed off, but I didn’t notice anything unusual except that he didn’t eat the dinner he ordered.”

In a telephone interview, the lineman who parked the accident pilot next to his waiting friends said he had been an emergency medical technician “for 15 years” and immediately noticed that the pilot struggled to egress his airplane and appeared “befuddled” when he got out. He asked if the pilot wanted fuel or any other services, and the pilot “wouldn’t” respond. A pilot outside the party of three confronted the accident pilot about entering the traffic pattern and landing in the opposite direction without making any radio calls. The lineman said that the pilot did not respond, continued to appear “befuddled,” and that his friends “defended him” and then took him away to go to lunch. The other pilots explained that the accident pilot “didn’t have a radio” as the radio in his airplane was inoperative. He added, “I feared for the pilot because he was ‘devastated’ by what he had done. He was wrong, both on the landing and when he taxied. He looked devastated.”

The Federal Aviation Administration (FAA) medical certification file and the pilot’s pre-event medical records were reviewed by a National Transportation Safety Board medical officer.

The 68-year-old male pilot was operating under the provisions of BasicMed. His most recent FAA medical certification examination was on May 20, 2014, at which time he reported taking aspirin and having no medical conditions. The remains of the pilot were not found; no autopsy report or toxicology testing results were available.

Pre-event medical records showed that the pilot had a history of coronary artery disease and had angioplasty and stenting of his left main, left anterior descending, and left circumflex coronary arteries in 2018. His exercise nuclear study on November 9, 2021, was abnormal with a reduced ejection fraction and systolic function. While there was no current ischemia, there was evidence of a past infarct. He had swelling of both legs and was being treated for fluid retention and high blood pressure. He was also being treated for high lipid levels, diabetes, and gastric reflux disease. The pilot had a body mass index of 35. There were no other significant physical exam findings.