# NTSB CEN20FA023: Piper PA24, N6678P, San Antonio, TX, December 2, 2019 - Type: NTSB accident investigation - Classification: Accident · Fatal · Class 3 · Field · Final report - Date: December 1, 2019, 18:25 local (Dec 2, 2019, 00:25 UTC) - Place: San Antonio, TX - Coordinates: 29.550832, -98.499725 - Nearby events: https://openairdocs.org/map.md?lat=29.5508&lon=-98.4997&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Fatal - Injuries: 3 fatal - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: Piper Aircraft, Lycoming, FAA - NTSB case key (mKey): 100637 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN20FA023 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/100637/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=100637 - Page: https://openairdocs.org/ntsb/CEN20FA023 ## Probable cause The loss of engine power for reason that could not be determined. Contributing to the accident was the pilot’s failure to maintain aircraft control while maneuvering to landing which resulted in an inadvertent stall/spin with insufficient altitude to recover. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating)](https://openairdocs.org/ntsb-findings/01058500): Aircraft › Aircraft power plant · Unknown/Not determined (probable cause); cases with it: [Piper PA-24-250, 6 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md?model=7102404), [All aircraft, 497 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Piper PA-24-250, 12 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=7102404), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Piper PA-24-250, 8 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=7102404), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Approach: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Piper PA-24-250, 22 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=7102404), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-24-250, 55 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7102404), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis While en route to the destination, the pilot reported to air traffic control that he had an “engine failure” and declared an emergency. The pilot was cleared to land at another airport and responded that he would be “circling above” the airport before landing. Flight track data revealed that the airplane procced away from the runway, then descended and turned back inbound. Analysis of ADS-B data revealed that the calibrated airspeed decreased below the airplane published stall speed of 56 knots. The tower controller and a ground witness observed the airplane in a steep nose down attitude and spiral into the ground. Surveillance video also captured the airplane in a steep descent and counterclockwise spiral before it impacted terrain. The airplane sustained substantial damage to both wings, the empennage, and the fuselage. Examination of the airplane and engine did not reveal any preimpact mechanical malfunctions or anomalies that would have precluded normal operation. Chordwise scratches were detected on 2 of the 3 propellers blades, which indicates that the engine was likely producing some power at the time of impact. It could not be determined what kind of engine malfunction the pilot experienced. It also could not be determined if the pilot intended to continue the approach to the runway or to land on a nearby street. The circumstances of the accident are consistent with the loss of engine power reported by the pilot for undetermined reasons because an examination of the engine did not reveal any preimpact malfunctions. The pilot subsequently allowed the airspeed to decrease below stall speed while maneuvering to land, which resulted in an inadvertent stall/spin on approach with insufficient altitude to recover. ## Factual narrative A review of engine maintenance logbook entries found the most recent work occurred on November 14, 2019, which consisted of an oil change and new oil filter installed on the airplane. The mechanic noted that no foreign debris was detected in the previous filter. An operational check of the engine was recorded with “no leaks found.” At the time of the work, the engine had 4,686.4 total hours and 555.3 hours since major overhaul. Before that, on April 17, 2019, an annual inspection was completed on the engine, no discrepancies were identified during that inspection. A fuel receipt was located in the wreckage which showed that the airplane was fueled with 33 gallons of 100 low lead aviation fuel at David Wayne Hooks Memorial Airport on the morning of the accident. San Antonio International Airport is located near San Antonio, Texas. It is serviced by 3 runways: 4/22, 13L/31R, and 13R/31L. Runway 13R is 8,502 ft long. The intended runway the pilot was flying an approach to was Runway 13R which is 8,502 ft long and 150 ft wide. It is lit with runway lighting, approach lighting, and precision approach path indicator lights. On December 1, 2019, about 1825 central standard time, a Piper PA24-250 airplane, N6678P, was substantially damaged when it was involved in an accident near the San Antonio International Airport (KSAT), San Antonio, Texas. The private pilot, flight instructor, and passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The flight was conducted under a visual flight rules flight plan, at night, with flight following. The airplane departed Sugar Land Regional Airport (SGR), Houston, Texas, about 1716 with the intended destination of Grier Airport (71TX), Boerne, Texas. Paperwork found in the airplane showed that the pilot was training for an airplane instrument rating, although it is unknown if training was being conducted before the accident, or if the training was to begin at 71TX. While in cruise flight, the pilot reported to San Antonio Approach Control that the airplane experienced an “engine failure” and declared an emergency. The pilot initially accepted clearance to circle for runway 04 at SAT and was then cleared to circle “at his discretion.” The pilot reported that he had the airport in sight and was cleared to land on runway 13R. The pilot responded that they were “circling above” and would land on runway 13R. During the approach, a brief radio transmission with the sound of someone distressed was heard on tower’s radio frequency and the tower controller witnessed the airplane in a spiraling descent. A witness on the ground described seeing the airplane turn to the east and then the airplane went “nose down” towards the ground. A review of Automatic Dependent Surveillance-Broadcast (ADS-B) data captured the airplane’s path as it approached the San Antonio area. The data were analyzed, and knots calibrated airspeed (KCAS) was derived for thisdescription of the flight. The flight path was headed toward OWEKY, an approach fix for the RNAV 35 approach to Boerne Stage Field (5C1), until about 1822 when the airplane began to maneuver to land on runway 13R at SAT. The airplane flew to the southwest and descended to about 2,900 ft mean sea level (MSL) when the airplane rolled out toward the approach end of 13R. At this point, the airplane was about 2,000 ft above the touchdown zone elevation of the runway, about 0.48 nautical miles from the runway threshold, and 1,200 ft right of runway centerline. The pilot continued a descending left turn and flew away from runway 13R for about 0.6 nautical miles and descended to 2,000 ft MSL. At 1825:13, the airplane began a left turn for runway 13R at an airspeed of 66 KCAS. Halfway through the turn, the airplane’s airspeed was 76 KCAS, and the descent rate increased to about 1,200 ft per minute (fpm). As the airplane was almost 180° through the turn back to runway 13R, the descent rate increased to over 6,000 fpm and the airspeed increased to 93 KCAS before the airspeed began to decay. At 1825:29 the airplane tracked southeast towards the runway, generally along Rhapsody Drive. At 1825:30.7, the airplane slowed below the published stall speed of 56 knots with the last point about 50 KCAS. According to the airplane flight manual, the published stall speed for landing gear and flaps up is 62 knots. The published stall speed with the landing gear and flaps extended is 56 knots. A surveillance camera captured the airplane’s impact with terrain. The camera was oriented south and was focused on a parking lot and Rhapsody Drive. The first indication of the accident airplane was the landing lights which illuminated the ground and rotated in a counterclockwise circle. The lights made about one full rotation before the airplane entered the field of view. The airplane was pointed about 70° nose down. The top of the airplane pointed toward the camera as it rapidly descended and the airplane was in a counterclockwise spiral as it impacted terrain. An autopsy was conducted on the private pilot by the Bexar County Medical Examiner’s Office. The autopsy ruled the cause of death was a result of blunt force injuries. Toxicology testing performed by the FAA’s Forensic Services Laboratory identified no evidence of impairing drugs. An autopsy was conducted on the flight instructor by the Bexar County Medical Examiner’s Office. The autopsy ruled the cause of dead was a result of blunt force injuries. Toxicology testing performed by the FAA’s Forensic Services Laboratory identified the presence of ethanol in the liver (12 mg/dL) but not in muscle, as well as the presence of amlodipine and atorvastatin, which had been previously reported to the FAA. Amlodipine is a prescription medication used alone or in combination with other medications to treat high blood pressure. Atorvastatin is a prescription medication used to reduce high cholesterol and triglyceride levels. Theprivate pilot owned the accident airplane. His logbook number “2” was recovered at the accident site. It revealed that the pilot received his private pilot endorsement on October 3, 2014. He flew often and received instrument flight training from the accident flight instructor. It is unknown if instrument training was being conducted on the accident flight. The pilot had accumulated at least 151.4 hours in the accident airplane and about 404.9 total hours. A record of his most recent flight review was not located in the available logbook. The flight instructor’s logbook was not made available for the investigation. She held a current Federal Aviation Administration (FAA) BasicMed certificate dated March 8, 2018. On a previous medical application dated May 12, 2016, she reported having accrued over 2,150 total hours. It could not be determined if the flight instructor was acting as an instructor during this flight or was a pilot-rated-passenger. The airplane impacted in a nose low attitude in an empty parking lot. A small crater in the asphalt was the initial impact point and the wreckage was found about 10 ft from the crater. All major airplane components were located at the accident scene. Flight control continuity was established from the cockpit controls to the flight control surfaces. Flap position could not be determined. The landing gear switch was in the down position and bent downwards. All fuel screens were clear of debris. The left wing’s fuel filler access door was opened, and an orange microfiber towel was found wedged between the access door and the filler cap. The cap was found to be loose and could be removed without loosening the rubber stopper. The lift detector was impacted damaged and testing of the vane could not be accomplished; however, electrical continuity was confirmed with an ohmmeter. The stabilizer trim jackscrew was found in a setting consistent with partial nose-up trim. Examination of the engine revealed that the crankshaft was fractured, so it was further examined by the National Transportation Safety Board Materials Laboratory. The fracture surface was consistent with overstress and there was no evidence of preexisting damage. The remainder of the engine did not display any anomalies which would have precluded normal operation. The metal, 3-bladed Hartzell propeller remained attached to the engine and was examined. The blades were labelled A, B, and C for documentation purposed. Blade A exhibited chordwise scratches along the cambered side and aft bending and twisting of the outer portion. Blade B exhibited a few chordwise scratches along the cambered side. Blade C was bent aft beginning about 12” from the hub but was relatively undamaged. ## Aircraft - Registration: [N6678P](https://openairdocs.org/deregistered/N6678P-2022-02-05), registration cancelled 2022-02-05, S/N 24-1802 (OpenAirDocs) - Reported make and model: Piper PA24 (250) - Registry model: [Piper PA-24-250](https://openairdocs.org/model/piper-pa-24-250) (registry code 7102404) (OpenAirDocs) - Category: Airplane - Serial number: 24-1802 - Year built: 1960 - Engines: Lycoming O-540-A1D5 250 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 17, 2019 - Departed: SGR, Houston, TX - Destination: 71TX, Boerne, TX - Flight plan: IFR - Airport: SAT, San Antonio Intl, runway 13R, 8,502 × 150 ft, concrete - Equipment: ADS-B, Auto-pilot, Electronic multifunction display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 38; injuries: fatal; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; seat: left; toxicology performed; flight hours: 404.9 total, 151.4 in this make and model, 60.2 in the last 90 days, 9 in the last 30 days, 2.5 in the last 24 hours - Flight instructor; age 71; injuries: fatal; commercial, flight instructor; instrument ratings: airplane; medical: basicmed; seat: right; toxicology performed; flight hours: 2,150 total ## Weather - Conditions: Visual (VMC), Night - Wind: 320° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 54 °F, dew point 30 °F - Altimeter: 30.19 inHg - Observed at: KSAT, 1 nm away - METAR: METAR KSAT 020051Z 32004KT 10SM CLR 12/M01 A3019 RMK AO2 SLP214 T01221006= ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20191201022039A](https://openairdocs.org/incident/20191201022039A), Dec 1, 2019: Piper PA-24-250, San Antonio, TX, Destroyed, 3 fatal. During cruise flight N6678P declared an engine failure to sat ATC and was cleared to ksat. During approach N6678P lost airspeed, stalled and crashed, fatally… ## Other investigations on N6678P (4) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB LAX78FUG14](https://openairdocs.org/ntsb/LAX78FUG14), Jan 22, 1978: Piper PA-24 (N6678P), Ontario, CA, substantial damage - [NTSB LAX66F0203](https://openairdocs.org/ntsb/LAX66F0203), Jan 17, 1966: Piper PA-24 (N6678P), Reno, NV, substantial damage - [NTSB SEA66F0003](https://openairdocs.org/ntsb/SEA66F0003), May 30, 1965: Piper PA-24 (N6678P), Seatte, WA, substantial damage - [NTSB UNK64X3489](https://openairdocs.org/ntsb/UNK64X3489), Aug 20, 1964: Piper PA24 (N6678P), Delhi, CA, substantial damage ## Docket (18 files) The files NTSB released with the investigation on February 8, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=100637. 27.1 MB in all. - Examination notes (item 1, PDF, 2 pages, 17 photos, 171 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12946392&FileExtension=pdf&FileName=Examination%20Notes%20CEN20FA023-Rel.pdf - Materials laboratory factual report 20-002 (item 2, PDF, 3 pages, 3 photos, 274 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9028746&FileExtension=pdf&FileName=20-002-Rel.pdf - Police report information (item 3, PDF, 1 page, 118 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12798430&FileExtension=pdf&FileName=Police%20Report%20Information-Rel.pdf - Video synopsis (item 4, PDF, 1 page, 115 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12945959&FileExtension=pdf&FileName=CEN20FA023%20video%20synopsis-Rel.pdf - Pre-impact photo markup added (item 5, PDF, 1 page, 434 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12797805&FileExtension=pdf&FileName=impact%20photo%20markup-Rel.pdf - Private pilot toxicology (item 6, PDF, 1 page, 647 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12797915&FileExtension=pdf&FileName=Private%20Pilot%20Tox_Redacted-Rel.pdf - CFI toxicology (item 7, PDF, 1 page, 646 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12798017&FileExtension=pdf&FileName=CFI%20tox_Redacted-Rel.pdf - Medical information (item 8, PDF, 2 pages, 171 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12945759&FileExtension=pdf&FileName=Medical%20Information-Rel.pdf - ATC audio summary (item 9, PDF, 4 pages, 633 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12799083&FileExtension=pdf&FileName=ATC%20Audio%20summary-Rel.pdf - Photos (item 10, PDF, 6 pages, 3.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12799178&FileExtension=pdf&FileName=CEN20FA023%20Photos%206-Rel.pdf - Sound spectrum analysis (item 11, PDF, 1 page, 113 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12942280&FileExtension=pdf&FileName=Sound%20Spectrum%20Attempt-Rel.pdf - Recent work (item 12, PDF, 1 page, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12942643&FileExtension=pdf&FileName=Recent%20work%20done_Redacted-Rel.pdf - Pages from engine log (item 13, PDF, 2 pages, 285 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12942148&FileExtension=pdf&FileName=Pages%20from%20Engine%20Logs_Redacted-Rel.pdf - Vehicle performance (item 14, PDF, 1 page, 203 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12942653&FileExtension=pdf&FileName=DANTE%20work%20CEN20FA023-Rel.pdf - Dante output csv file (item 15, CSV, 247 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12942200&FileExtension=csv&FileName=--%20DANTE%20OUTPUT%20--%20with%20plots%20-%20FINAL-Rel.csv - ADS-B overlays on google earth (item 16, PDF, 3 pages, 9.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12946061&FileExtension=pdf&FileName=Overlays-Rel.pdf - ADS-B data cvs (item 17, CSV, 8.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12946382&FileExtension=csv&FileName=20191201_A8D1B8_415436458_ADSB-Rel.csv - Party member form (item 18, PDF, 1 page, 132 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12945769&FileExtension=pdf&FileName=NTSB%20party%20form%20-%20CEN20FA023_Redacted-Rel.pdf From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.