# NTSB DFW08FA056: Aero Commander 500B, N712AT, Tulsa, OK, January 17, 2008 - Type: NTSB accident investigation - Classification: Accident · Fatal · Field investigation · Final report - Date: January 16, 2008, 22:43 local (Jan 17, 2008, 04:43 UTC) - Place: Tulsa, OK - Coordinates: 36.225833, -95.889442 - Nearby events: https://openairdocs.org/map.md?lat=36.2258&lon=-95.8894&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed, report June 11, 2009 - Report: Approved by Office Director - Parties: Air Central Southwest, Parker Parker Hannifin, transportation Safety Institute, Lycoming Textron, Twin Commander, Federal Aviation Administration, FSDO, Hartzell Propellers and Governors - NTSB case key (mKey): 67386 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DFW08FA056 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/67386/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=67386 - Page: https://openairdocs.org/ntsb/DFW08FA056 ## Probable cause The pilot's loss of control due to spatial disorientation and the pilot exceeding the design/stress limits of the aircraft. Factors contributing to the accident were the pilot's reported gyro problem, the dark night conditions , and prevailing instrument meteorological conditions. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Vacuum system: vacuum indicating system](https://openairdocs.org/ntsb-findings/01023720): Aircraft › Aircraft systems · Malfunction (probable cause); cases with it: [Aero Commander 500-B, 1 case](https://openairdocs.org/ntsb-findings/01023720/cases.md?model=0141106), [All aircraft, 1 case](https://openairdocs.org/ntsb-findings/01023720/cases.md) - [Perception/orientation/illusion: spatial disorientation](https://openairdocs.org/ntsb-findings/02022025): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Aero Commander 500-B, 1 case](https://openairdocs.org/ntsb-findings/02022025/cases.md?model=0141106), [All aircraft, 358 cases](https://openairdocs.org/ntsb-findings/02022025/cases.md) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Aero Commander 500-B, 2 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=0141106), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md) - [Aircraft](https://openairdocs.org/ntsb-findings/01030000): Aircraft › Aircraft structures · Capability exceeded (probable cause); cases with it: [Aero Commander 500-B, 1 case](https://openairdocs.org/ntsb-findings/01030000/cases.md?model=0141106), [All aircraft, 72 cases](https://openairdocs.org/ntsb-findings/01030000/cases.md) - [Light condition: dark](https://openairdocs.org/ntsb-findings/03036020): Environmental issues › Conditions/weather/phenomena · Not specified (probable cause); cases with it: [Aero Commander 500-B, 1 case](https://openairdocs.org/ntsb-findings/03036020/cases.md?model=0141106), [All aircraft, 448 cases](https://openairdocs.org/ntsb-findings/03036020/cases.md) - [Ceiling/visibility/precip: below VFR minima](https://openairdocs.org/ntsb-findings/03035075): Environmental issues › Conditions/weather/phenomena · Not specified (probable cause); cases with it: [Aero Commander 500-B, 1 case](https://openairdocs.org/ntsb-findings/03035075/cases.md?model=0141106), [All aircraft, 184 cases](https://openairdocs.org/ntsb-findings/03035075/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Flight instrument malf/fail](https://openairdocs.org/ntsb-events/334); cases with it: [Aero Commander 500-B, 1 case](https://openairdocs.org/ntsb-events/334/sequence.md?model=0141106), [All aircraft, 56 cases](https://openairdocs.org/ntsb-events/334/sequence.md) - [Initial climb: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Aero Commander 500-B, 3 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=0141106), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) - [Initial climb: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Aero Commander 500-B, 2 cases](https://openairdocs.org/ntsb-events/060/sequence.md?model=0141106), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Initial climb: Aircraft structural failure](https://openairdocs.org/ntsb-events/337); cases with it: [Aero Commander 500-B, 2 cases](https://openairdocs.org/ntsb-events/337/sequence.md?model=0141106), [All aircraft, 290 cases](https://openairdocs.org/ntsb-events/337/sequence.md) ## Analysis The commercial pilot departed on a night instrument flight rules flight in actual instrument meteorological in-flight conditions. Less than 2 minutes after the airplane departed the airport, the controller observed the airplane in a right turn and instructed the pilot to report his altitude. The pilot responded he thought he was at 3,500 feet and he thought he had lost the gyros. The pilot said he was trying to level out, and when the controller informed the pilot he observed the airplane on radar making a 360-degree right turn , the pilot said "roger." Three minutes and 23 seconds after departure the pilot said "yeah, I'm having some trouble right now" and there were no further radio communications from the flight. The on scene investigation disclosed that both wings and the tail section had separated from the airframe. All fractures of the wing and wing skin were typical of ductile overload with no evidence of preexisting failures such as fatigue or stress-corrosion. The deformation of the wings indicated an upward failure due to positive loading. No anomalies were noted with the gyro instruments, engine assembly or accessories ## Factual narrative HISTORY OF FLIGHT On January 16, 2008, at 2043 central standard time, a twin-engine Aero Commander 500-B airplane, registered as N712AT, was destroyed during an in-flight break-up and subsequent impact with terrain following a loss of control after take-off from Runway 36L at the Tulsa International Airport, near Tulsa, Oklahoma. The commercial pilot, sole occupant of the airplane, was fatally injured. The airplane was registered to and operated by Central Air Southwest, Inc., of Kansas City, Missouri, and was being utilized as an on demand air-carrier flight, hauling canceled bank checks. Dark night instrument meteorological conditions prevailed in the area at the time for the cargo flight conducted under 14 Code of Federal Regulations Part 135. An instrument flight rules flight plan had been filed and activated for the 94-nautical mile night cross-country flight from the Tulsa International Airport (TUL) to the Wiley Post Airport (PWA), near Oklahoma City, Oklahoma. Authorities at the airport reported that soon after departing TUL, the pilot reported that he was having gyro problems. The airplane was observed on radar and was given instructions to turn left to 300 degrees. The pilot initiated a right turn and was informed by Tulsa approach control that "you are turning right, turn left to 300 degrees." The aircraft continued a steep right turn for two complete 360 degree turns and disappeared from the radar scope. The wreckage of the airplane was located about 90 minutes after the accident in a remote wooded area of Mohawk Park, approximately 1 3/4 miles north of the airport. There was no fire. INJURIES TO PERSONS The pilot was fatally injured. There were no injuries to anyone on the ground. DAMAGE TO AIRCRAFT The wreckage of the twin-engine airplane was located about 90 minutes after the accident in a remote wooded area of Mohawk Park, approximately 1.75 miles north of the airport (010 degrees from the departure end of the runway). There was no post-impact fire. PERSONNEL INFORMATION The 31-year old instrument rated pilot held a commercial certificate for single and multi-engine land airplanes. His last first class medical certificate was issued on November 19, 2007. The operator reported that the pilot had accumulated a total of 4,373-flight hours, of which 695-hours were in the same make and model aircraft. Additionally, the pilot was reported to have accumulated 255-hours in the preceding 90-days, with l83 in the last 30 days. The pilot's last biennial flight review was completed on November 29, 2007, in an Aero Commander 500-B. The operator reported that the pilot was very familiar with the airplane and he had completed the scheduled flight almost on a daily basis since he joined the company. AIRCRAFT INFORMATION The 1961-model Aero Commander 500-B, serial number 1118-68, was reported to have accumulated a total of 17,888-flight hours at the time of its last inspection on January 10, 2008. The airplane has a maximum takeoff weight of 6,750-pounds, and the weight of the airplane at the time of takeoff from Tulsa was estimated at 6,005-pounds. The aircraft was powered by two-290-horsepower IO-540-B1A5 Lycoming engines. The number one engine (left), serial number L-154-48, had accumulated a total of 126-hours since its last overhaul. The number two engine (right), serial number RL-7521-48, had accumulated a total of 1,276-hours since its last overhaul. METEOROLOGICAL INFORMATION The weather at the TUL airport at the time of the accident was reported as, a broken ceiling at 600 feet, an overcast ceiling at 1,900 feet, visibility 3 miles in rain and snow, temperature 31 degrees Fahrenheit, with winds from 300 degrees at 18 knots, gusting to 24 knots. The pilot was reported to have received a weather briefing for the flight. COMMUNICATIONS The Tulsa Air Route Traffic Control Center (ARTCC) personnel reported that at 45 seconds into the flight the pilot of N712AT, was cleared to climb to 6,000-feet and was given a left turn to a heading of 250-degrees, and cleared direct to PWA. The accident pilot acknowledged this transmission. At 1 minute and 59 seconds into the flight the controller noted that N712AT was in a right turn. At 2 minutes and 55 seconds the controller requested N712AT to report the altitude he was leaving and the pilot responded "3,500 I think I have lost my gyros, I'm trying to level out now". The controller responded "roger, you just made a right 360," to which the pilot responded "roger." At 3 minutes and 23 seconds after departure, the controller transmitted "712AT, you still appear to be in a right turn," to which the pilot responded "yeah, I'm having some trouble right now." At 3 minutes and 54 seconds the controller transmitted "712AT, I'm not getting a target on you, say altitude now." No response was received from the accident aircraft, and the accident airplane had disappeared from the radar scope. No further transmissions were received by the Tulsa ARTCC personnel. WRECKAGE AND IMPACT INFORMATION Examination of the aircraft wreckage was conducted at the accident site on January 18, 2008. The fractures were photographed and visually examined with a 10x magnifier and a high intensity light. The first piece of aircraft wreckage along the debris field was the outboard portion of the left wing. The left wing was perched at a 45 degrees angle between two trees preventing extensive examination at its final resting place of North 36 degrees 13 minutes 7.51 seconds, West 95 degrees 53 minutes 4.46 seconds per the Tulsa Fire Department (TFD). All fractures of the wing structure (spars, longerons, and ribs) and wing skin were typical of ductile overload with no evidence of preexisting failures such as fatigue or stress-corrosion. Overall deformation of the wing indicated failure upward due to positive loading. The second piece of the aircraft wreckage found was the outboard portion of the right wing. The right wing was resting in a pile of broken tree limbs preventing extensive examination at its final resting place of North 36 degrees 13 minutes 8.54 seconds, West 95 degrees 53 minutes 5.54 seconds per the TFD. All fractures of the wing structure (spars, longerons, and ribs) and skin were typical of ductile overload with no evidence of preexisting failures such as fatigue or stress-corrosion. Overall deformation of the wing indicated failure upward due to positive loading. The empennage was found at North 36 degrees 13 minutes 8.64 seconds, West 95 degrees 53 minutes 5.74 seconds. The empennage was resting upright on its tail cone and its left and right horizontal stabilizer tips. The empennage separated from the aircraft at the fuselage-empennage junction just forward of the vertical stabilizer. All fractures of the fuselage-empennage structure (stringers) and skin were typical of ductile overload with no evidence of preexisting failures such as fatigue or stress-corrosion. Overall deformation of the fuselage-empennage junction indicated failure to the starboard side. The leading edges of the vertical stabilizer and the left horizontal stabilizer contained mechanical damage due to impact with the outboard portion of the right wing (detailed later). The bottom surface of the left horizontal stabilizer contained torsion buckles forward-aft indicating upward loading and the bottom surface of the right horizontal stabilizer contained torsion buckles aft-forward indicating downward loading. The left horizontal stabilizer upward loading and the right horizontal stabilizer downward loading indicates rolling of the aircraft from left to right which is characteristic of an in-flight breakup due to the right wing failing first. The rudder was found approximately 20 yards north of the empennage. The rudder was fractured and folded in half. All the fractures of the rudder structure and skin were typical of ductile overload wit ## Aircraft - Registration: [N712AT](https://openairdocs.org/deregistered/N712AT-2009-10-01), registration cancelled 2009-10-01, S/N 500B-1118-68, built 1961 (OpenAirDocs) - Reported make and model: AERO COMMANDER 500B - Registry model: [Aero Commander 500-B](https://openairdocs.org/model/aero-commander-500-b) (registry code 0141106) (OpenAirDocs) - Registry engine: [Lycoming TI0-540 series](https://openairdocs.org/engine/lycoming-ti0-540-series) (registry code 41533, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 1118-68 - Airframe hours: 17888 - Engines: Lycoming IO540-E1A5 290 horsepower reciprocating; Lycoming IO540-E1A5 290 horsepower reciprocating - Damage: Substantial damage - Flight: Part 135 - Operator: Central Air Southwest, doing business as Central Air Southwest, Inc. - Registered owner: Central Air Southwest - Airworthiness certificate: Standard, Utility; Standard, Normal - Last inspection: AAIP, January 10, 2008 - Departed: KTUL, Tulsa, OK - Destination: KPWA, Oklahoma City, OK - Flight plan: IFR - Airport: KTUL, Tulsa International Airport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: fatal; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review November 29, 2007; seat: left; toxicology performed; flight hours: 4,373 total, 695 in this make and model, 255 in the last 90 days, 83 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Instrument (IMC), Night - Wind: 300° at 18 knots, gusting 21 - Visibility: 3 statute miles - Lowest ceiling: 800 ft overcast - Temperature: 32 °F, dew point 34 °F - Altimeter: 30.00 inHg - Observed at: KTUL, 1 nm away ## 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 20080116010449A](https://openairdocs.org/incident/20080116010449A), Jan 16, 2008: Gulstm 500B, Tulsa, OK, Destroyed, 1 fatal. (-23) Aircraft departed Tulsa international (tul) airport at 2240HRS CST enroute to wiley post (pwa). After departure tul tower called pilot and he reported a… ## Docket (20 files) The files NTSB released with the investigation on April 3, 2009, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=67386. 15.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 488 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311050&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Witness Statements (item 2, .PDF, 110 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311051&FileExtension=.PDF&FileName=Witness%20Statements-Redacted.PDF - Maps or Charts of Accident Area, Wreckage Diagrams (item 3, .PDF, 3 photos, 630 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311052&FileExtension=.PDF&FileName=Maps%20or%20Charts%20of%20Accident%20Area,%20Wreckage%20Diagrams-Master.PDF - Wreckage Diagram (item 4, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40435262&FileExtension=.PDF&FileName=Wreckage%20Diagram-Redacted.PDF - Weather Reports and Records (item 5, .PDF, 12 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311053&FileExtension=.PDF&FileName=Weather%20Reports%20and%20Records-Master.PDF - Reports from Local Agencies - Tulsa Police Report (item 6, .PDF, 512 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40435263&FileExtension=.PDF&FileName=Reports%20from%20Local%20Agencies%20-%20Tulsa%20Police%20Report-Redacted.PDF - Reports from Parties to the Investigation - TSI (item 7, .PDF, 14 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311056&FileExtension=.PDF&FileName=Reports%20from%20Parties%20to%20the%20Investigation%20-%20TSI-Redacted.PDF - Reports from Parties to the Investigation - Hartzell Propellers (item 8, .PDF, 10 photos, 248 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311057&FileExtension=.PDF&FileName=Reports%20from%20Parties%20to%20the%20Investigation%20-%20Hartzell%20Propellers-Master.PDF - Reports from Parties to the Investigation - Parker Hannifin Extract (item 9, .PDF, 189 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311058&FileExtension=.PDF&FileName=Reports%20from%20Parties%20to%20the%20Investigation%20-%20Parker%20Hannifin%20Extract-Redacted.PDF - Other Pertinent Forms and Reports - Fuel Receipts (item 10, .PDF, 69 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311061&FileExtension=.PDF&FileName=Other%20Pertinent%20Forms%20and%20Reports%20-%20Fuel%20Receipts-Master.PDF - Toxicological Report (item 11, .PDF, 481 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311059&FileExtension=.PDF&FileName=Toxicological%20Report-Master.PDF - Statement of Party Representatives to NTSB Investigation (item 12, .PDF, 186 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311106&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Master.PDF - Photo 1 - Main wreckage 3 o'clock. (item 13, .PDF, 4.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311065&FileExtension=.PDF&FileName=Photo%201%20-%20Main%20wreckage%203%20o%27clock.-Master.PDF - Photo 2 - Main Wreckage 12 o'clock (item 14, .PDF, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311069&FileExtension=.PDF&FileName=Photo%202%20-%20Main%20Wreckage%2012%20o%27clock-Master.PDF - Photo 3 - Main Wreckage 10 o'clock (item 15, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311075&FileExtension=.PDF&FileName=Photo%203%20-%20Main%20Wreckage%2010%20o%27clock-Master.PDF - Photo 4 - Main Wreckage 9 o'clock (item 16, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311077&FileExtension=.PDF&FileName=Photo%204%20-%20Main%20Wreckage%209%20o%27clock-Master.PDF - Photo 5 - Main Wreckage 7 o'clock (item 17, .PDF, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311078&FileExtension=.PDF&FileName=Photo%205%20-%20Main%20Wreckage%207%20o%27clock-Master.PDF - Photo 6 - Right Wing (item 18, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311080&FileExtension=.PDF&FileName=Photo%206%20-%20Right%20Wing-Master.PDF - Photo 7 - Tail section (item 19, .PDF, 1000 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311081&FileExtension=.PDF&FileName=Photo%207%20-%20Tail%20section-Master.PDF - Photo 8 - Aerial View (item 20, .PDF, 912 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40311083&FileExtension=.PDF&FileName=Photo%208%20-%20Aerial%20View-Master.PDF From the NTSB's public API. 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