# NTSB MIA97FA213: Gates Learjet 35A, N19LH, Avon Park, FL, July 15, 1997 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Field investigation · Final report - Date: July 15, 1997, 19:53 local (23:53 UTC) - Place: Avon Park, FL - Location: 27.5897° N, 81.5073° W: Placed by OpenAirDocs: center of Avon Park, FL, within about 6 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=27.5897&lon=-81.5073&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report May 4, 1998 - Report: Approved by Office Director - ADs cited in the narratives: [AD 79-08-01 R1](https://openairdocs.org/ad/79-08-01-R1) (OpenAirDocs) - NTSB case key (mKey): 38148 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA97FA213 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/38148/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=38148 - Page: https://openairdocs.org/ntsb/MIA97FA213 ## Probable cause a loss of engine power as a result of the thrust reversers being deployed and subsequent in-flight collision was wires. Factors in this accident were the pilot's disregard for procedures, and the improper use of the thrust reversers. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, landing - aborted - all available runway - not used, pilot in command - emotional reaction, pilot in command - procedures/directives - not complied with, pilot in command (contributing factor) - aborted landing - initiated, pilot in command - thrust reverser - deployed inadvertently (cause) - reversers - improper use of, pilot in command (contributing factor) - In flight collision with object, climb - object - wire,static - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground ## Analysis Witnesses near the airport saw the flight approach on a left base to runway 4, touchdown on the runway, and takeoff again. One witness, a pilot, said the airplane turned onto final to the 'south' (right) of the runway centerline.' The airplane made a 'sharp' turn to the left to realign with the runway center, slightly overshot the runway to the left, turned to the right 'sharply,' and touched down on the runway. The witness further stated, '...by the time the pilot was on the runway he had wasted approximately 1,200 to 1,500 feet of runway 4, they hit reverse thrusters [sic] and were on full bore till they crossed runway 27 and 9.' The witness saw heat come out of both engine thrust reversers, the nose gear touched down and then came up again. He then saw the airplane come off the ground about 30 to 40 feet, wobble left and right at a 'slow airspeed,' crossover a highway at a low altitude, right wing low, strike some wires, go into a field, and catch fire. The pilot said, when he touched down on the runway, the airplane seemed to 'lurch' to the side. He said at this point his airspeed was 126 knots. He elected to abort the landing, and applied full power. He said the engines would not develop thrust and he elected to land in a field less than 1/4 mile in front of him. Examination of the left thrust reverser revealed that the translator was in the deployed position, with the blocker doors fully open. Both the left and right pneumatic latches were found in the unlocked position. Examination of the right thrust reverser revealed that the translator was in the deployed position, with the blocker doors fully closed. The left pneumatic latch was found in the locked position. The right pneumatic latch was found in the unlocked position. The inboard sequence latches were found about 2 inches forward of full aft travel. The thrust reverser switch was found in the 'NORMAL' position. According to Gates Lear Jet Airworthiness Directive (AD) 79-08-01, '...to preclude inadvertent thrust reverser deployment and possible loss of aircraft control....,' the following limitations apply to all gates Lear Jet Model 35, 36, 35A, 36A, aircraft equipped with Aeronca Thrust reversers. According to the AD, Section I-LIMITATION; '....Thrust Reversers must not be operated prior to takeoff...Thrust Reversers must not be used for touch and go landings...After Thrust Reversers have been deployed, a visual check of proper door stowing must be made prior to takeoff...Operational Procedures in this Thrust Reverser Supplement are mandatory.' According to Lear Jet and FlightSafety International, the procedures that are taught to Lear Jet pilots in the use of thrust reverse and spoilers during landings are; '...pilots [are] to use thrust reverse only on full stop Lear Jet landings. Pilot are trained not to deploy spoilers or thrust reverse during touch and go's or during balked landings.' The pilot-in-command of N19LH at the time of the accident, told the NTSB investigator-in-charge (IIC) that he was 'aware' of the limitations on the Aeronca Thrust Reverser and he knew that once the Thrust Reverser was deployed that he was 'committed' to land. The pilot told the IIC that he knew of the limitations and that he was committed to land. ## Factual narrative HISTORY OF FLIGHT On July 15, 1997, about 1953 eastern daylight time, a Gates Learjet 35A, N19LH, registered to Orion Aircraft Sales Inc., crashed after an aborted landing at Avon Park, Florida. Visual meteorological conditions prevailed at the time and an instrument flight rules (IFR) flight plan was filed for the Title 14 CFR Part 91, positioning flight. The airline transport-rated pilot and commercial-rated copilot received minor injuries. The airplane was destroyed. The flight had originated from the Fort Lauderdale Executive Airport, Florida, the same day at 1917. At 1853:56, the pilot of N19H, called the St. Petersburg AFSS (Automated Flight Service Station) to file an IFR flight plan. He was informed by the briefer that his flight plan data was entered into the system. The telephone conversation was ended at 1855:17. The flight proceeded without incident, and at 1930:00, the flight was cleared to descend to 4,000 feet. A subsequent clearance to 3,000 feet was issued at 1937:27. The pilot cancelled IFR at 1938:28, and radar service was terminated. Witnesses near the airport saw the flight circle once over the airport, approach on a left base to runway 4, touchdown, and takeoff again. One witness, a pilot, told the NTSB IIC (investigator-in-charge) that he observed the airplane turn onto final to the "south" (right) of the runway centerline." The airplane made a "sharp" turn to the left to realign with the runway center, slightly overshot the runway to the left, turned to the right "sharply," and touched down on the runway. The witness further stated, "...by the time the pilot was on the runway he had wasted approximately 1,200 to 1,500 feet of runway 4, they hit reverse thrusters [sic] and were on full bore till they crossed runway 27 and 9." The witness saw heat come out of both engine thrust reversers, the nose gear touched down and then came up again. He then saw the airplane come off the ground about 30 to 40 feet, wobble left and right at a "slow airspeed," crossover a highway at a low altitude, right wing low, strike some wires, go into a field, and catch fire. The pilot in a statement to local police said, when he touched down on the runway, the airplane seemed to "lurch" to the side. He said, at this point his airspeed was 126 knots. He elected to abort the landing, and applied full power. He said the engines would not develop thrust and he elected to land in a field less than 1/4 mile in front of him. The accident occurred during the hours of dusk approximately 27 degrees, 35 minutes north, and 081 degrees, 31 minutes west. PERSONNEL INFORMATION Information on the pilot is contained in this report on page 3, under First Pilot Information. Information on the second pilot is contained in this report on Supplement E. METEOROLOGICAL INFORMATION Visual meteorological conditions prevailed at the time of the accident. Meteorological information is contained in this report on page 3, under Weather Information. FLIGHT RECORDERS The Universal model 30A cockpit voice recorder (CVR), was examined at the NTSB audio laboratory on July 23, 1997, and a transcript was prepared of 02:55 minutes of the 32:03 minute recording. Information and the transcript of the CVR are contained in this report, under Cockpit Voice Recorder, Factual Report of Group Chairman. WRECKAGE AND IMPACT INFORMATION An examination of runway 4, revealed that there were no parts of the airplane found on the runway or the areas around the runway. A walk of runway 4 by the NTSB, FAA and parties to the investigation revealed that skid marks similar to a Learjet landing gear signature was found about 1,800 feet from the approach end of runway 4. There was no confirmation that the marks were from N19H, and no marks in the touchdown area could be identified as being from N19H. There were no marks observed on the runway that could be identified as going off the left or right side of the runway. After leaving the runway the airplane traveled on a heading of 040 degrees about 1,000 feet and was seen by the witness striking a single power line, and cutting the line. Scrape marks from the right wing tip tank were found in the pavement of the road. The airplane was then seen impacting right wing first in a field behind a building, striking a tractor mower and continuing on a heading of 040 degrees shedding parts for about 450 feet. The airplane came to rest with the fuselage and nose of the airplane heading north. Examination of the wreckage at a hanger at the Avon Park Airport, revealed that the left wing was about 60 percent consumed by fire. The leading edge had a section of cable lodged in it at about wing station (WS) 177. The right wing had displayed fire damage at both the center section and the outboard end. The right wing tip tank and wing extension separated at WS 181. The right tip tank fin was scratched and bent. The fuselage had separated from the wing and was broken in two, about station 346.63. Wrinkling and damage was observed all along the fuselage. Examination of the empennage revealed that the left horizontal and left elevator were bent down and under the horizontal stabilizer. The left forward engine beam failed at the fuselage with about 12 inches of the upper cap staying with the mount and engine. The mount displayed evidence of bending moments in both the up and down directions. The right forward engine beam was broken at the fuselage, and displayed a downward load at the fracture surface. The left engine was attached to the airplane, but had come to rest on the right side of the fuselage, and was being held in place by wiring and hoses. Observation of the engine revealed signs of rotation on the fan blades. The right engine had separated during the impact sequence. Observation of the engine revealed signs of rotation on the fan blades. The airplane was equipped with two Aeronca Thrust reversers. Examination of the left thrust reverser revealed that the translator was in the deployed position, with the blocker doors fully open. The translator was found 1 1/2 inches to 3 inches from full aft travel. Both the left and right pneumatic latches were found in the unlocked position. The inboard sequence latch was found about 3 inches forward of full aft travel. The latch hammer was engaged. The outboard sequence latch was found about 1 1/2 inches forward of full aft travel. The latch hammer was disengaged. Both the inboard and outboard flex drive cable cores were found in an unserviceable condition. The pneumatic actuator was cranked by hand with the flex drive cables removed. The actuator motor was not seized and appeared to be operational. Examination of the right thrust reverser revealed that the translator was in the deployed position, with the blocker doors fully closed. The translator was found 1 to 2 inches from full aft travel. The left pneumatic latch was found in the locked position. The right pneumatic latch was found in the unlocked position. The inboard sequence latch was found about 2 inches forward of full aft travel. The stop housing was broken and found in the lower access area of the thrust reverser body. The attaching screws, sliding blocker, pivoting blocker and housing fingers were still attached to the beam. The latch hammer position could not be determined. The outboard sequence latch was found about 1 inch forward of full aft travel. The latch hammer was disengaged. The inboard flex drive cable core was found sheared at the upper pinion gear box end, and was in an unserviceable condition. The outboard flex drive cable core was found in an unserviceable condition. The pneumatic actuator was cranked by hand with the flex drive cables removed. The actuator motor was not seized and was operational. The lower inboard operating rod displayed an "S" shaped bend. The corresponding yoke base was also bent. The ## Aircraft - Registration: [N19LH](https://openairdocs.org/deregistered/N19LH-1998-12-22), registration cancelled 1998-12-22, S/N 279 (OpenAirDocs) - Reported make and model: Gates Learjet 35A - Registry model: [Gates Learjet 35A](https://openairdocs.org/model/gates-learjet-35a) (registry code 5170602) (OpenAirDocs) - Category: Airplane - Serial number: 279 - Airframe hours: 13726 - Engines: Garrett 731-2-2B 3500 lbs thrust turbo fan - Damage: Destroyed - Fire: On-Ground - Flight: Positioning, Part 91 - Registered owner: Orion Aircraft Sales Inc. - Airworthiness certificate: Standard, Utility - Last inspection: Continuous airworthiness, February 6, 1997, 190 hours before - Departed: FXE, FT LAUDERDALE, FL - Destination: AVO - Flight plan: IFR - Airport: AVO, Avon Park Municipal, runway 4, 4,000 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; flight instructor, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 20,076 total, 1,500 in this make and model, 19,000 as pilot in command, 194 in the last 90 days, 55 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Dusk - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 70 °F - Altimeter: 30.00 inHg - Observed at: GIF, 35 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 19970715018569A](https://openairdocs.org/incident/19970715018569A), Jul 15, 1997: Lear 35A, Avon Park, FL, Destroyed. Unstable approach landed long. Used buckets. Tried go around in reverse thrust hit wires. Reverser cables corroded. (.19) on July 15, 1997, about 1953 eastern… ## Docket (23 files) The files NTSB released with the investigation on March 3, 1998, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=38148. 5.2 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 432 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434418&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Supplement C (item 2, .PDF, 403 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080773&FileExtension=.PDF&FileName=Supplement%20C-Master.PDF - Supplement D (item 3, .PDF, 541 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080774&FileExtension=.PDF&FileName=Supplement%20D-Master.PDF - Supplement E (item 4, .PDF, 117 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434415&FileExtension=.PDF&FileName=Supplement%20E-Redacted.PDF - Supplement K (item 5, .PDF, 424 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080776&FileExtension=.PDF&FileName=Supplement%20K-Master.PDF - Maps or Charts of Accident Area, Wreckage Diagrams (item 6, .PDF, 46 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080777&FileExtension=.PDF&FileName=Maps%20or%20Charts%20of%20Accident%20Area,%20Wreckage%20Diagrams-Master.PDF - Cockpit Voice Recorder - Factual Report (item 7, .PDF, 308 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434416&FileExtension=.PDF&FileName=Cockpit%20Voice%20Recorder%20-%20Factual%20Report-Redacted.PDF - Materials Laboratory - Factual Report (item 8, .PDF, 61 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434417&FileExtension=.PDF&FileName=Materials%20Laboratory%20-%20Factual%20Report-Redacted.PDF - Witness Statements (item 9, .PDF, 154 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434419&FileExtension=.PDF&FileName=Witness%20Statements-Redacted.PDF - Transcript of Radio Communications (item 10, .PDF, 178 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434420&FileExtension=.PDF&FileName=Transcript%20of%20Radio%20Communications-Redacted.PDF - Highlands Co. Sheriff's Office Report (item 11, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434421&FileExtension=.PDF&FileName=Highlands%20Co.%20Sheriff%27s%20Office%20Report-Redacted.PDF - Statement of Party Representatives to NTSB Investigation (item 12, .PDF, 74 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434422&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation-Redacted.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 13, .PDF, 81 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434423&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-Redacted.PDF - Memorandum From Flight Safety International (item 14, .PDF, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40434424&FileExtension=.PDF&FileName=Memorandum%20From%20Flight%20Safety%20International-Redacted.PDF - Photo 1. General view of the crash site. Photo taken to the east in the direction of travel (item 15, .PDF, 130 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080787&FileExtension=.PDF&FileName=Photo%201.%20General%20view%20of%20the%20crash%20site.%20Photo%20taken%20to%20the%20east%20in%20the%20direction%20of%20travel%20-Master.PDF - Photo 2. General view of the crash site. Photo taken to the west opposite the direction of travel. (item 16, .PDF, 109 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080788&FileExtension=.PDF&FileName=Photo%202.%20General%20view%20of%20the%20crash%20site.%20Photo%20taken%20to%20the%20west%20opposite%20the%20direction%20of%20travel.-Master.PDF - Photo 3. The right wing is shown in the foreground of the photo. The arrow points to the wire that witnesses said they saw the airplane's right wing strike. (item 17, .PDF, 167 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080789&FileExtension=.PDF&FileName=Photo%203.%20The%20right%20wing%20is%20shown%20in%20the%20foreground%20of%20the%20photo.%20The%20arrow%20points%20to%20the%20wire%20that%20witnesses%20said%20they%20saw%20the%20airplane%27s%20right%20wing%20strike.%20-Master.PDF - Photo 4. Arrow No. 1 points to the wire shown in photo No.3 Arrow No 2. points to the runway at Avon Park Airport. (item 18, .PDF, 116 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080790&FileExtension=.PDF&FileName=Photo%204.%20Arrow%20No.%201%20points%20to%20the%20wire%20shown%20in%20photo%20No.3%20Arrow%20No%202.%20points%20to%20the%20runway%20at%20Avon%20Park%20Airport.-Master.PDF - Photo 5. Right tip tank. (item 19, .PDF, 134 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080791&FileExtension=.PDF&FileName=Photo%205.%20Right%20tip%20tank.-Master.PDF - Photo 6. Wire marks found on the right tip tank. (item 20, .PDF, 111 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080792&FileExtension=.PDF&FileName=Photo%206.%20Wire%20marks%20found%20on%20the%20right%20tip%20tank.-Master.PDF - Photo 7. Left Engine. The arrow points to the thrust reverser translator in the deployed position. (item 21, .PDF, 159 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080793&FileExtension=.PDF&FileName=Photo%207.%20Left%20Engine.%20The%20arrow%20points%20to%20the%20thrust%20reverser%20translator%20in%20the%20deployed%20position.%20-Master.PDF - Photo 8. Right engine. The arrow points to the thrust reverser translator in the deployed position. (item 22, .PDF, 155 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080794&FileExtension=.PDF&FileName=Photo%208.%20Right%20engine.%20The%20arrow%20points%20to%20the%20thrust%20reverser%20translator%20in%20the%20deployed%20position.%20-Master.PDF - Photo 9. Right engine. The arrow points to the thrust reverser blocker doors in the fully closed position. (item 23, .PDF, 134 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40080795&FileExtension=.PDF&FileName=Photo%209.%20Right%20engine.%20The%20arrow%20points%20to%20the%20thrust%20reverser%20blocker%20doors%20in%20the%20fully%20closed%20position.-Master.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.