ERA11LA397

NTSB accident investigation · Gates Lear Jet 35 · Opa-Locka, FL · July 12, 2011

Accident · No injuriesLimited investigationFinal report
Date
July 12, 2011, 13:20 local (17:20 UTC)
Place
Opa-Locka, FL
Injuries
4 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N110UNGates Lear Jet 35
Defining event
Landing-flare/touchdown: Windshear or thunderstorm
Weather
Visual (VMC) · Day
Status
Completed · report November 7, 2012
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20110712012839A
Case key
81093

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The flightcrew’s inadvertent encounter with windshear during landing, which resulted in a loss of control.

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Wind: windshearEnvironmental issues › Conditions/weather/phenomena · Effect on equipmentGates Lear Jet 35: 1 caseAll aircraft: 90 casesProbable cause
Performance/control parameters: lateral/bank controlAircraft › Aircraft oper/perf/capability · Attain/maintain not possibleGates Lear Jet 35: 1 caseAll aircraft: 390 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

When the pilot made his initial radio contact with the tower air traffic controller, he acknowledged receiving the airport’s latest automatic terminal information service information. As the airplane approached the airport, the controller made several announcements that there was an area of weather about 5 miles in diameter with light-to-moderate precipitation over the airport. The pilot reported that, during the landing, at an altitude of about 30 feet above the runway, the airplane encountered windshear. The airplane started to roll to the left, and the airspeed decreased by 20 knots. As the pilot attempted to regain control of the airplane, the right wingtip contacted the runway surface. A review of high resolution automated surface observation system data from the airport indicated that, 2 minutes before the accident, the wind was from 338 degrees at 4 knots. Subsequently, there was a steady increase in wind velocity to 15 knots 4 minutes after the accident. During this 6 minute period, the wind direction varied between 353 degrees and 011 degrees. Terminal Doppler weather radar data indicated strong convective activity northwest of the airport from 2 minutes before to 10 minutes after the accident with possible micro bursts and diverging winds near the surface from the time of the accident to 5 minutes after the accident.

Factual narrative

On July 12, 2011, about 1320 eastern daylight time, a Gate Lear Jet 35, N110UN, encountered windshear during landing at Opa-Locka Executive Airport (OPF), Opa-Locka, Florida. The pilot, copilot, and two passengers were not injured. The airplane incurred substantial damage. Visual meteorological conditions prevailed, and no flight plan was filed for the test flight, which was conducted under the provisions of 14 Code of Federal Regulations Part 91. The flight originated from OPF, about 1256. The pilot stated that the intent of the flight was to test the airplane's systems for an upcoming flight. The departure from OPF was toward the northwest and they flew towards the Lake Okeechobee area, then towards the Naples area, and then flew back to OPF for a full stop landing. During the approach to runway 12 at OPF, rain was observed west of the airport. During the landing, at an altitude of about 30 feet above the runway, the airplane encountered windshear. The airplane started to roll to the left and the airspeed decreased by 20 knots. As the pilot attempted to regain control of the airplane, the right wingtip made contact with the runway surface. At that moment, he believed the airplane's position was almost perpendicular to the runway. He applied differential engine power and applied aggressive flight control inputs to stay on the runway. Once in control of the airplane, the pilot taxied toward the end of the runway, and off the active runway towards the operator's ramp area were the airplane came to a complete stop and was shutdown. Upon further inspection by the flight crew, it was discovered that the extension section (fuel tank) of the outboard right wing had separated from the wing attachment point and was hanging by the lower wing skin. The pilot, age 43, held an Airline Transport pilot certificate, with ratings for airplane multiengine land, airplane single-engine land, LR-JET, HS-125, EA-500S, DA-10, and instrument airplane. In addition, he held a flight instructor certificate with ratings for airplane-single engine, airplane multiengine, and instrument airplane. The pilot reported that he accumulated 13,594 total hours of flight experience, of which, 1,100 hour were in the same make and model as the accident airplane. His most recent Federal Aviation Administration first-class medical certificate was issued on September 3, 2010. The copilot, age 72, held a commercial pilot certificate, with ratings for airplane multiengine land, airplane single-engine land, and instrument airplane. The copilot reported that he accumulated 2,500 total hours of flight experience. His most recent Federal Aviation Administration second-class medical certificate was issued on October 23, 2010. Published information for runway 12/30 at OPF shows it as a grooved asphalt, 6800 foot long by 150 foot wide, with a 800 feet displaced threshold, at an elevation of 8 feet mean sea level (msl). Runway 12 is equipped with a visual slope indicator. The OPF airport is notequipped with a low level windshear alert system (LLWAS). Audio recording from the OPF tower communication revealed the pilot acknowledged receiving the airport’s latest Automatic Terminal Information Service (ATIS) when he made his initial radio contact with the controller when the flight was 16 miles west of the airport. The controller made several announcements on the airport traffic frequency that there was an area of weather 5 miles in diameters with light to moderate precipitation over the airport prior to the landing. The airplane’s cockpit voice recorder was retained and reviewed at the NTSB Recorders Laboratory; the event was captured. The adverse weather condition advisory from the OPF controller was captured as the flight crew were preparing for the landing on runway 12. There was nothing out of the normal or concerning heard during the approach to the runway. As the airplane was over the approach end of the runway, the stick shaker followed by 2 loud bangs, followed by the stick shaker again followed by 3 more loud bangs were heard. The pilot was heard stating “we lost the airspeed indicator”. The 1326 special recorded weather observation at OPF, included wind from 340 degrees at 15 knots gusting to 20 knots, visibility 8 miles, moderate rain, overcast clouds at 3,700 feet above ground level, temperature 29 degrees C, dew point 26 degrees C; altimeter 30.05 inches of mercury. A review of high resolution automated surface observation system data from OPF indicated that at 1318, the wind was from 338 degrees at 4 knots. Then, there was a steady increase in wind velocity to 15 knots at 1324. During that time, the wind shifted between 353 degrees and 011 degrees. Terminal Doppler weather radar data indicated strong convective activity northwest of the airport between 1318 and 1330. The data also identified possible micro bursts and diverging winds near the surface around 1320 to 1325 northwest of OPF. As a result of this accident a direct line of communication has been established between the OPF tower and the National Oceanic and Atmospheric Administration’s (NOAA), Miami, Florida, Center Weather Service Unit to disseminate hazard weather conditions that may affect operations at or near the OPF area.

Aircraft

Registration
N110UN
Reported as
Gates Lear Jet 35
Category
Airplane
Serial number
007
Airframe hours
19,128
Engines
Airesearch TFE731 SER, 3,500 lbs thrust, turbo fanAiresearch TFE731 SER, 3,500 lbs thrust, turbo fan
Damage
Substantial damage
Flight
Flight test · Part 91
Operator
Robinson Air Crane, Inc.
Registered owner
Robinson Air Crane, Inc.
Airworthiness certificate
Standard, Normal
Last inspection
Continuous airworthiness · February 15, 2011 · 0 hours before
Departed
OPF · Opa-Locka, FL
Destination
OPF · Opa-Locka, FL
Airport
OPF · Opa-Locka Executive, runway 12, 6,800 × 150 ft, asphalt

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
43
Injuries
None
Certificates
Airline transport, Flight instructor, Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, With waivers/limitations
Last flight review
October 11, 2010
Seat
Left
Flight hours
13,594 total · 1,100 in this make and model · 61 in the last 90 days · 14 in the last 30 days · 2 in the last 24 hours
Role
Co-pilot
Age
72
Injuries
None
Certificate
Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Last flight review
January 6, 2010
Seat
Right
Flight hours
2,500 total · 1,200 as pilot in command · 25 in the last 90 days · 10 in the last 30 days · 3 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
340° at 15 knots, gusting 20
Visibility
8 statute miles
Lowest ceiling
3,700 ft overcast
Temperature
84 °F, dew point 79 °F
Altimeter
30.04 inHg
Observed at
OPF

Docket · 14

The files NTSB released with the investigation on August 9, 2012, on NTSB’s docket system: statements, records, photos and specialists’ reports. 11.7 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.