# NTSB CEN20FA076: Beech 33, N6665U, Granbury, TX, February 8, 2020 - Type: NTSB accident investigation - Classification: Accident · Fatal · Class 3 · Field · Final report - Date: February 8, 2020, 13:17 local (19:17 UTC) - Place: Granbury, TX - Coordinates: 32.497222, -97.861389 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=32.4972&lon=-97.8614&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Defining event: [Approach-VFR pattern base: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: Flight Standards District Office, Continental Motors, Textron Aviation - NTSB case key (mKey): 100915 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN20FA076 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/100915/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=100915 - Page: https://openairdocs.org/ntsb/CEN20FA076 ## Probable cause The pilot's exceedance of the airplane's critical angle of attack while maneuvering in the airport traffic pattern, which resulted in an aerodynamic stall and loss of control. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Beech F33A, 3 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=1151425), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Beech F33A, 9 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1151425), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach-VFR pattern base: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Beech F33A, 4 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=1151425), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) ## Analysis The pilot was conducting a personal flight to a nearby airport. Flight tracking information and a statement from another pilot indicated that the pilot overflew the runway, entered the airport traffic pattern, landed, and taxied the airplane off the runway. About 7 minutes later, the airplane was captured on radar as it flew downwind in the traffic pattern and proceeded north. About 2 minutes later, the radar data ended; the accident site was located 0.39 nautical mile north-northeast of the final radar return. The airplane impacted trees and terrain in a nose-low attitude with minimal forward momentum and a slightly twisted empennage, consistent with an aerodynamic stall/spin. Examination of the airplane did not reveal any mechanical malfunctions or anomalies that would have precluded normal operation. It is likely that the pilot was flying an extended pattern and turning from the base to final legs of the pattern when he exceeded the airplane's critical angle of attack, which resulted in an aerodynamic stall, loss of control, and impact with terrain. ## Factual narrative The responding Federal Aviation Administration (FAA) inspector spoke to an MWL airport employee who fueled the accident airplane before the pilot departed on the accident flight. She stated that the pilot requested fuel "to the slots," and she added 13 gallons of fuel to obtain that level. The fuel filler port placards on the airplane wings stated, "CAP TO TAB SLOT 35 GAL (32 USABLE)." On February 8, 2020, at 1317 central standard time, a Beech F33A airplane, N6665U, was substantially damaged when it was involved in an accident near Granbury, Texas. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 as a personal flight. A review of the recorded radar and automatic dependent surveillance – broadcast (ADS-B) data revealed that the airplane approached Granbury Regional Airport (GDJ), Granbury, Texas, from the northwest about 1301 and overflew runway 14 at 900 ft above ground level (agl). After overflying the runway, the airplane turned right toward the northwest on a wide downwind leg and gradually descended to about 400 ft agl. The airplane made a right base turn, where the first set of data ended at 1305:07, about 440 ft agl, and 93 knots groundspeed. At 1314:18, radar data showed a target on the southwest side of GDJ that proceeded to the north toward the accident site and ended at 1316:51. The accident site was located 0.39 nautical miles north-northeast of the final radar return. Figure 1 shows the recorded flight track with the accident site and GDJ airport labeled. Figure 1 – Radar and ADS-B track in red with the accident site and GDJ airport labeled Further review of the ADS-B data showed that at least three other airplanes were also flying in the immediate GDJ airport environment at the same time as the accident airplane. As the accident airplane was on short final, one airplane had just departed GDJ and proceeded southeast. The second airplane was in a right traffic pattern and ahead of the accident airplane. The third airplane was circling above the traffic pattern, then descended and followed the accident airplane into the traffic pattern. The pilot of this third airplane remembered the accident airplane and stated that he entered the traffic pattern behind it and completed an S-turn maneuver for appropriate spacing. He continued in the pattern behind the accident airplane and watched it land and taxi toward the hangars and did not see the airplane again. The GDJ airport manager stated that his employees did not see the accident airplane arrive that day. The Office of the Chief Medical Examiner, Tarrant County Medical Examiner's District, Tarrant County, Texas, performed an autopsy of the pilot. The pilot's cause of death was massive blunt force trauma. The FAA Forensic Sciences Laboratory performed toxicology testing on specimens from the pilot. The specimens were positive for ethanol and propanol in the muscle, which were likely post-mortem. There were no drugs or medicationsdetected. The pilot recently completed a flight review on January 7, 2020. The flight was a 1.2-hour round trip from Mineral Wells Airport (MWL), Mineral Wells, Texas, to GDJ and back, and included steep turns, slow flight, stalls, cross-country navigation, preflight planning, autopilot use, and three takeoffs and landings. The accident site was located in an area of flat, rocky terrain about 3.75 miles northwest of GDJ at 830 ft mean sea level. The airplane impacted the ground in a 45° nose-down attitude and was oriented on a 068° true heading. The empennage was bent upward and slightly to the left, and the elevators rested on a tree. The airplane remained situated on top of the initial ground impact marks. Examination of the wreckage revealed that the leading edges of both wings were breached at the rivet lines and were split open. The fuel bladders in each wing had ruptured and were significantly damaged. A large portion of the right main fuel bladder and the entire fuel transmitter assembly had been ejected and were found about 10 ft in front of the wing. The wing tip tanks sustained impact damage and large portions of the tanks were fractured and displaced forward and outward. The dirt and organic debris in front of the wings was displaced forward. The fuel selector handle was positioned to the left main tank. The flap actuator revealed that the flaps were retracted during the impact and also the landing gear were found extended. Flight control continuity was established, and the examination did not reveal any mechanical malfunctions or anomalies that would have precluded normal operation. Examination of the engine revealed that most of the impact damage was sustained to the bottom of the engine. Crankshaft and camshaft continuity were confirmed when the crankshaft was rotated by hand. Five of six cylinders produced suction and compression and the sixth cylinder exhibited impact damage to the intake pushrod. The inside of each cylinder was examined with a lighted borescope; the cylinders displayed normal operating signatures with no anomalies noted. The spark plug electrodes all displayed normal wear and operating signatures. The fuel manifold valve remained attached to its installation point and was undamaged. The fuel line from the fuel flow transducer and the manifold valve was disconnected from the transducer and a small amount of liquid was drained. Its odor was consistent with fuel; the liquid was clear in color and tested negative for water. A small amount of gray, fibrous material was found in the fuel system in several places but was of insufficient quantity to affect fuel passage. The material was found in the unfiltered side of the manifold valve, in the inlet screen of the metering assembly, and in the fuel selector strainer. The propeller assembly was found in the initial impact crater embedded in the ground under the engine and was impact-separated from the engine crankshaft. Two of the propeller blades remained attached tothe hub; one blade was mostly straight and unremarkable and the other was bent slightly forward. The third blade had separated from the hub; it was found directly under the engine and was bent aft about mid-span. This blade also exhibited about one foot of scratches and superficial damage near the blade root. ## Aircraft - Registration: [N6665U](https://openairdocs.org/deregistered/N6665U-2021-04-03), registration cancelled 2021-04-03, S/N CE-880, built 1979 (OpenAirDocs) - Reported make and model: Beech 33 (F33A) - Registry model: [Beech F33A](https://openairdocs.org/model/beech-f33a) (registry code 1151425) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: CE-880 - Year built: 1979 - Airframe hours: 3939.87 - Engines: Continental Motors IO-550-B 300 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 11, 2019 - Departed: MWL, Mineral Wells, TX - Destination: GDJ, Granbury, TX - Airport: GDJ, Granbury Rgnl, runway 14, 3,603 × 60 ft, asphalt - Equipment: Auto-pilot, ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 71; injuries: fatal; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review January 7, 2020; seat: left; restraint: 3-point; toxicology performed; flight hours: 983 total, 907 as pilot in command, 2.7 in the last 90 days, 1.2 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 130° at 11 knots, gusting 14 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F, dew point 30 °F - Altimeter: 30.17 inHg - Observed at: KGDJ ## 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 20200208018199A](https://openairdocs.org/incident/20200208018199A), Feb 8, 2020: Beech F33A, Granbury, TX, Destroyed, 1 fatal. Accident description: the aircraft departed mineral wells airport (mwl) at 1251 CST, flying directly to gsj, then completing an 180 degree apparent normal rate… ## Docket (9 files) The files NTSB released with the investigation on December 1, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=100915. 36.1 MB in all. - NTSB examination summary (item 1, PDF, 8 pages, 2.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9856213&FileExtension=pdf&FileName=NTSB%20Exam%20Summary%20-%20CEN20FA076-Rel.pdf - Correspondence - records of conversation (item 2, PDF, 5 pages, 77 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=10022781&FileExtension=pdf&FileName=ROCs%20combined%20(5)-Rel.pdf - Photos (item 3, PDF, 5 pages, 5 photos, 17.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=10021090&FileExtension=pdf&FileName=Docket%20Photos-Rel.pdf - Maintenance records (item 4, PDF, 4 pages, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=10021981&FileExtension=pdf&FileName=Mx%20logs%20excerpts_Redacted2-Rel.pdf - Statement of party representatives to NTSB investigation (item 5, PDF, 2 pages, 850 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9125914&FileExtension=pdf&FileName=Party%20Forms%20(signed)_Redacted-Rel.pdf - Fuel receipt (item 6, PDF, 1 page, 61 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9131705&FileExtension=pdf&FileName=N6665U%20Fuel%20Invoice%20(MWL%202-8-20)_Redacted-Rel.pdf - Pilot logbook (item 7, PDF, 21 pages, 12.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9856028&FileExtension=pdf&FileName=Pilot%20logs%20all%202_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 8, PDF, 1 page, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9856910&FileExtension=pdf&FileName=Wreckage%20Release%20(signed)_Redacted-Rel.pdf - Toxicological report (item 9, PDF, 1 page, 160 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9855819&FileExtension=pdf&FileName=Tox%20-%20pilot_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.