N2428QPiper PA-46-310P · 1985

On June 18, 2014, about 1635 central daylight time, a Piper PA 46-310P airplane, N2428Q, crashed in an open field ½ mile east of Lehman, Texas. The private pilot and two passengers were fatally injured. The airplane was substantially damaged. The airplane was registered to Flying Lazy T, LLC., and operated by a private individual under the provisions of 14 Code of Federal Regulations (CFR) Part 91 as a personal flight. Both visual and instrument meteorological conditions existed for the flight, which operated on an instrument flight rules (IFR) flight plan. The cross country flight originated from Aspen-Pitkin County Airport/Sardy Field (KASE), Aspen, Colorado, at 1326 mountain daylight time, and was en route to Brenham Municipal Airport (11R), Brenham, Texas.

At 1517 central daylight time, N2428Q checked in with the Albuquerque Air Route Traffic Control Center (ZAB) controller at Flight Level (FL) 270. Between 1523 and 1526 N2428Q's altitude indicated 300 feet to 400 feet higher than the assigned altitude of FL270 four times. At 1530, the ZAB controller issued a Fort Worth Center Weather Advisory (CWA). Five minutes later, the controller transferred control of N2428Q to the next ZAB controller. N2428Q checked in with that controller at FL270.

At 1549, the controller issued convective SIGMET (Significant Meteorological Information) 86C for Texas. Between 1552 and 1607, N2428Q's altitude indicated 300 feet to 400 feet above and 400 feet below the assigned altitude of FL270 eight times. After each altitude deviation, N2428Q leveled at FL270. At 1554, after the second altitude deviation, the controller queried the pilot about the altitude changes. N2428Q reported that they were having autopilot issues. At 1556, during the altitude deviations, N2428Q requested and was authorized to deviate to the east of course for weather avoidance, but then deviated to the west.

About this time, a flight of two F/A-18s, call sign Cowboy 31, passed below N2428Q's flight track from west to east at FL250 and, according to the flight lead, encountered moderate clear icing and requested and were approved to descend to FL190.

At 1607 the ZAB controller transferred N2428Q to the next ZAB controller and from 1608 to 1617 N2428Q's altitude indicated 400 feet to 1,000 feet below the assigned altitude of FL270 three times. At 1615 the controller transferred N2428Q to the Fort Worth Air Route Traffic Control (ZFW) controller.

At 1617, N2428Q checked in with the ZFW controller at FL260 climbing to FL270 and advised the controller that he was in a turn for weather avoidance.

At 1630, N2428Q started a left turn and a climb. The ZFW controller asked N2428Q if he was going north for weather. The pilot responded that he "was trying to go through a window." As the pilot continued his climb out of FL270, the controller asked the pilot if he needed a higher altitude of FL290. The pilot did not respond. The controller then advised N2428Q that radar showed that he was in the middle of moderate to extreme precipitation and asked the pilot if he needed a different altitude. The pilot did not respond. Thirty seconds later the controller again tried to establish communications with N2428Q without success. This was followed immediately by a single "mayday" transmission on the frequency. At 1632 the controller asked N2428Q to say altitude and the pilot responded with "nineteen."

There were several aircraft on the frequency in the vicinity of N2428Q. N656FP, an Eclipse jet en route from Albuquerque, New Mexico, to Shreveport, Louisiana, was at FL410. The pilot of N656FP heard the situation developing on the frequency and, after the mayday call, asked the ZFW controller if they had heard it. The ZFW controller acknowledged with "N28Q, go ahead" after which someone on the frequency stated "oh, they just called a mayday to you." American Airlines flight 1536, also in the area at the time, reported that they had also heard the mayday call. In the meantime, the controller continued to try to reestablish communication with N2428Q and asked Alaska Airlines flight 670 if they would try to contact N2428Q.

At 1635, N2428Q reported that he was spinning. N656FP, in an effort to assist, asked the pilot of N2428Q if he could see the ground or the horizon, but did not receive a response. The ZFW controller asked N2428Q if he could see the ground but did not get a response. A transmission from one of the pilots in the vicinity transmitted that the last call from N2428Q was that he was spinning and had said something about not being able to see the ground or horizon.

American Airlines flight 2394 advised the ZFW controller that they had also heard N2428Q report that he was spinning. In response to a query from the controller, the pilot of American Airlines flight 2461 stated that he had heard N2428Q's transmissions but the words were so short that it was unclear what was said. United Airlines flight 1604 volunteered that they had heard N2428Q say he was spinning and that he had lost sight of the ground or horizon.

At 1638, another attempt by the ZFW controller to reestablish communications with N2428Q was unsuccessful. (Additional details and figures are available in the Air Traffic Control Factual Report available in the public docket.)

The wreckage was located in an open field by the land owner.

According to a witness in the area at the time of the accident, there was a severe thunderstorm in the immediate vicinity of the accident. The witness described high winds, heavy rain, and low visibility.

The pilot, age 61, held a private pilot certificate with an airplane single engine land and instrument airplane ratings. His most recent third class airman medical certificate was issued on November 26, 2013. At that time, the pilot reported no chronic medical conditions and no medications. The certificate contained the limitation "Must wear lenses for distant, have glasses for near vision. Holder shall possess glasses for near/intermediate vision." At the time of medical certificate application, the pilot estimated his total time as 2,500 hours, 30 of which had been logged in the previous 6 months.

On August 3, 2006, the Federal Aviation Administration (FAA) issued a Notice of Proposed Certificate Action to the pilot due to a suspension of driving privileges in the state of Colorado in 2004. The pilot did not report this suspension on his medical certificate application and argued that he had refused a breath test. His lawyer had argued the driving under the influence case down to "driving while impaired" and the pilot stated that his driver's license had not been suspended or revoked. On June 18, 2007, the FAA issued an Order of Revocation, immediately revoking the pilot's third class medical certificate. It was re-issued six months later.

The pilot applied for and received his instrument airplane rating on March 31, 2008. At the time of application he reported 754.6 hours of cross-country time as pilot in command and 70 hours of simulated/actual instrument time. Prior to this application, he had previously applied for, and been disapproved for the same rating. The record did not indicate which areas were deficient but did state all areas of operation were to be retested.

One pilot logbook was located in the wreckage of the airplane. The logbook contained flight log entries dated between September 4, 2011, and January 5, 2014. No flights were logged between January 5, 2014, and the date of the accident. All of the flights contained in the flight log were conducted in the accident airplane.

The pilot noted in his logbook if he had flown an instrument approach and he would log his total flight time; however, his landings and his instrument flight times were not annotated for each flight. The pilot had carried over a total time of 2,241.8 hours on the last page of the flight log. The total flight time logged on the last page was 16.6 hours. The last instrument approach annotated in his logbook was on August 12, 2013 – a Localizer DME 15 approach into ASE. He also annotated an instrument checkride on March 15, 2012. There were no endorsements in the back of the logbook, nor did any of the entries contain notes indicating a flight review or instrument competency check had been completed. Investigators were unable to determine if the pilot met the flight review or currency requirements as outlined in 14 CFR Part 61.56 Flight Review and Part 61.57 Recent flight experience: Pilot in command.

The accident airplane, a Piper PA 46-310P (serial number 46-8508088), was manufactured in 1985. It was registered with the FAA on a standard airworthiness certificate for normal operations. The airplane was originally certified by Piper with a Lycoming 350 horsepower reciprocating engine. A Pratt & Whitney PT6A-34 engine, with maximum continuous engine torque of 1,337 foot-pounds, powered the airplane at the time of the accident. The engine was equipped with a Hartzell (model HC-E4N-3I) 4-blade, variable pitch propeller.

The airplane was maintained under an annual inspection program. A review of the maintenance records indicated that an annual inspection had been completed on November 1, 2013, at an airframe total time of 4,735.5 hours (Hobbs 1,711.0 hours). The airplane had flown 64.4 hours between the last inspection and the accident and had a total airframe time of 4,799.9 hours.

The airplane had been equipped with the Supplemental Type Certificate ST00541SE in 1999. In the limitations section of the JetProp LLC Pilot Operating Handbook, flight above FL 270 was not approved. In addition, the altimeters in the airplane were only certified to 25,000 feet.

The synoptic or large scale migratory weather systems influencing the accident area were documented using standard National Weather Service (NWS) charts issued by the National Center for Environmental Prediction (NCEP) and the Weather Prediction Center (WPC).

Surface Analysis

The south central section of the NWS Surface Analysis Chart for 1600 on June 18, 2014, centered over Texas depicted a low pressure system over Colorado at 1000-hectopascals (hPa) along a stationary front, with a dry line that extended southward from the low across southeast Colorado and into eastern New Mexico. Ahead or east of the dry line, the chart depicted a relatively warm moist airmass that flowed northward from the Gulf of Mexico into northwestern Texas. The station models over the Texas Panhandle depicted southerly wind, partly cloudy skies, with temperatures in the 90's degrees Fahrenheit (F), and dew point temperatures above 60° F. Over New Mexico behind the dry line temperatures were also in the 90's with dew point temperatures below 40° F. The accident site was located in an area of general confluent wind flow ahead of the dry line.

Weather Radar

The National Center for Atmospheric Research (NCAR) - Research Application Laboratory (RAL) regional radar mosaic image for 1635 depicted several bands of intense radar echoes oriented in a general north-northeast to south-southwest bands across western Texas. The accident site was located in the immediate vicinity of one of the intense echoes. Additional scattered echoes continued to the south-southwestward into southeastern New Mexico and extreme southwestern Texas.

The NOAA National Climatic Data Center (NCDC) National radar reflectivity mosaic image for the same period of 1635 depicted a large organized area of echoes directly over Lehman, Texas, and immediately south, which were associated with an area of strong to severe multicellular to supercell-type thunderstorms.

NWS Convective Outlook

The NWS Storm Prediction Center (SPC) Convective Outlook chart issued at 1440 indicated that general thunderstorm activity was expected over the general route of flight with a slight risk of severe thunderstorms over northwestern Texas.

Surface Observations

The closest official NWS reporting location to the accident site was from Lubbock Preston Smith International Airport (KLBB), Lubbock, Texas approximately 50 miles east of the accident site at an elevation of 3,282 feet. The airport had an Automated Surface Observation System (ASOS) and was augmented by certified NWS weather observer during the period. The following conditions were reported near the time of the accident.

Lubbock Preston Smith International Airport (KLBB) weather observation at 1553, wind from 160° at 8 knots, visibility unrestricted at 10 miles, a few clouds at 6,000 feet agl, scattered 18,000 feet, scattered at 30,000 feet, temperature 32° Celsius (C), dew point temperature 17° C, altimeter 29.91 inches of mercury (Hg). Remarks: automated observation system, sea level pressure 1006.7-hPa, cumulonimbus clouds (CB) distant south and southwest through northwest, moving northeast slowly, towering cumulus clouds (TCU) distant northeast, altocumulus castellanus (ACC) distant northwest, temperature 32.2° C, dew point 16.7° C, 3-hour pressure tendency fallen 1.6-hPa.

The observations indicated that while visual meteorological conditions prevailed at the surface at the airport, high based thunderstorms were reported in the distance or beyond 10 miles and intermittently at the station after the accident in which a peak wind gust of 33 knots was reported associated with a thunderstorm. While the peak wind was below the classification of a severe thunderstorm, it still suggested a strong outflow from the storm. There was also a period of blowing dust reported, also indicative of strong outflow winds and/or potential microburst activity. There was also a high frequency of lightning activity reported during the period with the cumulonimbus clouds, which varied from occasional, to frequent, and after the accident was reported as continuous lightning activity.

Upper Air Data

The closest upper air sounding or rawinsonde observation (RAOB) was from the NWS Amarillo (KAMA) Weather Service Forecast Office (WSFO), located approximately 107 miles northeast of the accident site. The 1900 sounding depicted a warm low-level environment with a surface temperature of 86.7° F (30.4° C), and a dew point temperature of 59.7° F (15.4° C), with a relative humidity of 40%. The sounding indicated expected bases of the clouds between 7,500 to 8,000 feet agl, with expected convective cloud tops to approximately 45,000 feet, with the tropopause at 46,300 feet. The freezing level was identified at 15,414 feet and supported icing in clouds above that level.

The stability parameters indicated a very unstable atmosphere. The Severe Weather Threat Index indicated a moderate risk of severe thunderstorm development. The maximum vertical velocity of the potential updrafts was calculated at 142 knots. The sounding also supported hail, heavy rain, and/or downbursts with the thunderstorms across the region. The sounding stability indices indicated a moderate to strong risk of severe multicellular type thunderstorm development across the region.

The sounding wind profile depicted southerly winds from the surface through 19,000 feet with wind veering to the southwest with height with increasing wind speeds. A low level jet stream was identified at 4,850 feet agl with wind from 185° at 20 knots, with the level of maximum wind at 225° at 65 knots located below the tropopause at 43,990 feet. The 18,000 feet wind was from 213° at 25 knots with the mean storm motion from 243° at 19 knots. At the accident airplane's cruising altitude of 27,000 feet the wind was identified from 240° at 32 knots, with a temperature of -25° C. The sounding supported potential clear to mixed icing at 27,000 feet, especially with the convective updrafts which would have likely increased the icing potential at altitude.

Satellite Data

The Geostationary Operational Environmental Satellite number 13 (GOES-13) infrared image for 1630 at 4X magnification with a standard MB temperature enhancement curve illustrated cloud tops associated with deep convection and high cirriform clouds. Also added to the image was the frontal and dry line boundaries identified at 1600 by the NWS. The last radar contact was identified on the southwestern side of a band of cumulonimbus clouds with a radiative cloud top near 36,000 feet based on the KAMA sounding. Higher cloud tops were identified 6 miles north near 41,000 feet. The anvil tops of the cumulonimbus cloud extended northeastward and merged into another large cumulonimbus cloud system, which extended across most of the northern portion of the panhandle of Texas.

The GOES-13 visible images at 4X magnification at times 1545, 1615, 1625, 1630, 1637, 1645, 1655, and 1700 depicted the rapid development and growth of the cumulonimbus cloud during the period, and movement to the east-northeastward. The vertical extensive cumulonimbus cloud heights were also evident by the shadows under and immediately east of the clouds, and also depicted several overshooting cloud tops with the anvils.

In-Flight Weather Advisories

The NWS issued Severe Weather Forecast Alert (AWW) number 323 at 1447 and was valid through 2200 for severe thunderstorms over portions of Oklahoma and western Texas. The area was identified from 65 miles east and west of a line from 12 miles east-northeast of Lubbock, Texas, to 39 miles east of Liberal (KLBL), Kansas. The area was issued for a few severe thunderstorms with hail to 2 inches, extreme turbulence, and surface wind gusts to 60 knots. A few of the cumulonimbus clouds had a potential of maximum tops to 55,000 feet. The mean storm motion was from 240° at 20 knots.

The NWS also issued Convective SIGMETs that impacted the route of flight at 1455, 1555, and 1655. They called for areas of severe thunderstorms moving from the southwest at 15 knots, cloud tops to FL450, hail 1.5 inches in diameter, and wind gusts to 50 knots. The updated Convective SIGMET at 1555 increased the hail diameter to 2 inches and wind gusts to 60 knots.

The Albuquerque Air Route Traffic Control Center (KZAB) controller at 1530 broadcasted the issuance of KZFW CWA 201 and at 1549 Convective SIGMET 83C on the frequency and advised users to obtain further information on the nearest Hazardous Inflight Weather Advisory Service (HIWAS) broadcast. No other information relating to the nature of the hazard or the location of the advisories were provided, or mention of the weather watch 323 was made at that time..

At 1556, the Albuquerque controller advised on frequency that Convective SIGMET 86C was current and advised users to tune to HIWAS for further details. The airplane was equipped with the ability to access the recorded information; however, it is unknown if the accident airplane obtained the details of the advisory. CWA 202 was issued prior to the accident at 1630 and was not broadcasted by air traffic control until after the accident.

Immediately after the accident at 1655 Convective SIGMET 90C was issued over the accident site for a line of severe thunderstorms.

An extensive Meteorology Report with additional details and figures, illustrating the flight track and weather radar imagery, is available in the public docket for this report. The weather radar imagery (WSR-88D) shows the accident airplane deviating into a rapidly developing severe thunderstorm, when the altitude deviations and MAYDAY call are made.

Preflight Weather Briefing

The pilot's personal iPad was located in his luggage, in the wreckage of the airplane. The location suggested that it was not being used at the time of the accident or during the accident flight. The Safari application was the only open application. Within this there were two active tabs – one for Intellicast and the second for Airport Information. The first tab selected to Intellicast illustrated weather radar information for San Antonio, Texas, Abilene, Texas, and Dyees Air Force Base. The second tab illustrated airport information for Brenham Municipal Airport.

The accident pilot contacted Lockheed Martin Automated Flight Services Station (AFSS) at 1309 mountain daylight time on June 18, 2014. He filed an IFR flight plan from ASE to 11R, planning to depart at 1338 with an estimated time en route of 3 hours and 30 minutes. He was provided an abbreviated weather briefing which consisted of the destination METAR (routine aviation weather report), convective SIGMENT information, PIREPS (Pilot Reports), NOTAMS, and AIRMETS.

During the abbreviated weather briefing, the briefer discussed the dry line with moisture from the Gulf of Mexico flowing northward and the expected precipitation. The pilot of N2428Q acknowledged he was familiar with the expected conditions. During this period the briefer provided Convective SIGMET 76C, which related to a developing line of thunderstorms over southern Texas near the destination in the Houston area with the storms moving northward. At the time of the briefing no advisories for thunderstorms were current over western Texas or in the vicinity of the accident site, and the briefing did not mention or comment on the risk of severe thunderstorms expected during the period or forecast.

The accident airplane, a Piper PA 46-310P (serial number 46-8508088), was manufactured in 1985. It was registered with the FAA on a standard airworthiness certificate for normal operations. The airplane was originally certified by Piper with a Lycoming 350 horsepower reciprocating engine. A Pratt & Whitney PT6A-34 engine, with maximum continuous engine torque of 1,337 foot-pounds, powered the airplane at the time of the accident. The engine was equipped with a Hartzell (model HC-E4N-3I) 4-blade, variable pitch propeller.

The airplane was maintained under an annual inspection program. A review of the maintenance records indicated that an annual inspection had been completed on November 1, 2013, at an airframe total time of 4,735.5 hours (Hobbs 1,711.0 hours). The airplane had flown 64.4 hours between the last inspection and the accident and had a total airframe time of 4,799.9 hours.

The airplane had been equipped with the Supplemental Type Certificate ST00541SE in 1999. In the limitations section of the JetProp LLC Pilot Operating Handbook, flight above FL 270 was not approved. In addition, the altimeters in the airplane were only certified to 25,000 feet.

The main wreckage came to rest in an open field, oriented on an approximate heading of 270 degrees at an elevation of 3,770 feet. The main wreckage included the fuselage, empennage, both wings, and the engine and propeller assembly. There were no ground scars or debris field leading to the main wreckage.

The fuselage was buckled, wrinkled, and crushed in several directions along the entire span of the fuselage. The forward right side of the fuselage was torn and bent due to emergency responder activity. The floor of the fuselage, from the forward cabin, aft to the rear cabin seats and luggage area, was crushed up and wrinkled. All of the seats in the airplane remained attached. The internal ceiling and sidewall paneling in the fuselage separated partially and was scattered on the inside of the cabin.

The instrument panel in the forward cabin was crushed down and broken. Multiple switches and several instruments had separated from the panel and were impact damaged. Many of the engine instruments, the suction gauge, and fuel quantity instruments read zero. Readings from any of the digital displays and instruments were not recovered on scene. The following readings from the analog instruments and gauges were observed:

Pilot's side encoding altimeter – 3,670 feet

Pilot's side airspeed – zero

Turn coordinator – left wing down, 5 degrees, ball just left of center

Pilot's side artificial horizon – nose up 20 degrees, 5 degrees left wing down

Kollsman window – 29.90

Vertical speed indicator – 500 foot climb

Copilot's side altimeter – 3,220 feet

Kollsman window – 29.80

Copilot's side vertical speed indicator – 1,200 foot climb

Directional gyro – 135 degrees

Copilot's side airspeed – zero

Artificial horizon – 20 degrees nose down.

Turn coordinator – left wing down 5 degrees, wings level, ball just left of center

The landing gear actuator handle was selected to the down or extended position. The flap selector handle was selected to 20 degrees of flaps. In the throttle quadrant, the fuel was on, the propeller control was positioned at mid-range, and the throttle control was towards reverse. The friction lock was at midrange. The Hobbs meter showed a reading of 1,775.4 hours.

The right wing remained attached at the fuselage. The outboard portion of the wing separated partially at the production splice. The entire wing was bent and wrinkled. The de-ice boot was torn at the separation point but was otherwise unremarkable. The right flap was bent and wrinkled and separated partially at the outboard hinge. The flap appeared to be extended 20 degrees. The right aileron was deflected up and was bent. One flight control cable for the right aileron was broken in tension at the wing separation point. The second flight control cable was continuous from the aileron inboard to the wing root. The pushrod at the aileron control was broken, consistent with impact damage.

The right main landing gear remained attached to the wing. The hydraulic actuator was extended, consistent with the landing gear being extended. The right main landing gear strut was down and imbedded in the ground. The right main landing gear wheel assembly separated from the strut and came to rest under the trailing edge of the right flap.

The left wing remained attached to the fuselage. The de-ice boot was unremarkable. The wing was bent, buckled, and wrinkled along the entire span. The flap appeared to be extended approximately 20 degrees and remained attached to the wing. The left aileron remained attached to the wing but was bent and broken at the outboard hinge point. The flight controls were continuous but difficult to move, due to impact damage.

The empennage included the horizontal and vertical stabilizers, the elevator, and the rudder. The empennage separated at the rear pressure bulkhead, just forward of the vertical stabilizer leading edge. The fiberglass on the lower airfoil of the vertical stabilizer was torn. The leading edge of the stabilizer was otherwise unremarkable.

The rudder control was deflected to the right and the lower portion of the control was bent up and wrinkled. The control was jammed and difficult to move, due to impact damage. The control cables to the rudder were continuous.

The horizontal stabilizer was wrinkled along the leading edge. The de-ice boots were unremarkable. A witness mark, consistent with the bottom portion of the rudder control was located on the trailing edge of the right horizontal stabilizer, directly beneath the rudder control. The trim tab on the elevator was deflected up. The control cables to the elevator were continuous.

The engine remained attached to the fuselage. The fuselage forward of the cabin, up to the engine, was buckled up and wrinkled. The engine cowling was broken and torn. The engine was impact damaged and exhibited slight bending and twisting along the entire span of the engine.

The propeller assembly remained attached to the engine. Two blades separated from the engine and were imbedded in the soft ground directly beneath the engine. Both blades separated near the hub and were bent and exhibited polishing on the face of the blade and along the leading edge. Two other blades remained attached to the engine and were labeled "A" and "B" for identification purposes. Blade A was bowed more than 90 degrees and exhibited leading edge polishing and polishing and scratching along the face of the blade. Blade B was embedded in the ground and was bowed.

Thunderstorm Advisory Circular

The FAA Advisory Circular AC 00 – 24C "Thunderstorms" dated January 30, 2013, provided a basic review of thunderstorms and general guidance avoidance policy. The advisory circular described basic thunderstorm development, life cycle, organization or types of storms; from single cell, multicellular storms or clusters, to squall lines, and supercell type thunderstorms. A supercell is a single long-lived thunderstorm which is responsible for nearly all of the significant tornadoes produced in the United States and for most of the hailstones larger than golf ball-size.

The advisory circular also discussed thunderstorm terminology such as the use of the Convective Outlook (AC) and the perceived level of threat for convection and severe thunderstorms, and the general hazards within and near thunderstorms. Also included in the updated advisory circular with the use of ground-based weather radar, echo intensity or reflectivity, and the use of data link into the cockpit, as well as airborne weather radar and its primary limitation of attenuation and the need for proper tilt management. Avoidance of any heavy to extreme intensity echoes or one identified as severe by at least 20 miles was also emphasized.

According to the autopsy performed by South Plains Forensic Pathology, the cause of death was multiple blunt force trauma. The autopsy also identified an enlarged heart which weighed 440 grams (average for a 203 pound man is 375 grams with a range of 284-495 grams). In addition, there was coronary artery disease with an area of 80% stenosis in the first diagonal coronary artery. No other significant natural disease was identified.

Toxicology testing performed at the request of the pathologist by NMS laboratories found no ethanol but identified caffeine and 2.2 ng/ml of tetrahydrocannabinol (THC), the active ingredient in marijuana, in the pilot's blood.

Toxicology testing performed by the FAA's Bioaeronautical Research Laboratory found no ethanol but identified 1.9 ng/ml of tetrahydrocannabinol (THC) and 2.4 ng/ml of its inactive metabolite, tetrahydrocannabinol carboxylic acid (THC-OOH), in the pilot's blood as well as desmethylsildenafil, the metabolite of sildenafil (a prescription medication used to treat erectile dysfunction, also named Viagra), and zolpidem (a prescription sleep aid, marketed with the name Ambien) in the pilot's cavity blood. Urine testing identified desmethylsildenafil, ibuprofen (an over the counter analgesic commonly called Motrin and Advil), ranitidine (an over the counter medication used to treat heartburn, commonly known as Zantac), tetrahydrocannabinol carboxylic acid (117.4 ng/ml), and zolpidem. The report from the lab further noted that neither tetrahydrocannabinol nor tetrahydrocannabinol carboxylic acid were identified in brain tissue.

Airframe

Shop air at 30 psi was applied at the center air port in the empennage and the elevator de-ice boots and the rudder de-ice boot inflated without issue. Shop air at 40 psi was applied to the right wing and movement of the outboard de-ice section was observed. The left wing was impact damaged. Shop air at 50 psi was applied and the de-ice boots inflated to the second crimp in the wing. Impact damage precluded testing the remainder of the left wing de-ice boot.

Propeller Blades

The propeller blades that separated from the airplane and were under the wreckage were labeled "C" and "D" for identification purposes only. Both blades were bent, twisted, bowed, and exhibited leading edge polishing and scratching and polishing along the front and back of the blade.

Servos, Flight Computers, & Indicators

The flight computer, radios, rate gyro, and autopilot servos were removed from the airplane and sent to Honeywell for further examination and bench testing.

The pictorial navigation indicator and flight command indicator were impact damaged and could not be functionally tested. The directional gyro was functionally tested without anomaly.

The crystal in the flight computer was impact damaged preventing functional testing. Once the crystal was replaced the pitch and roll command, servo drive, and pitch trim functions were satisfactory. The altitude hold would not engage due to impact damage on the circuit board. The yaw computer and rate gyro passed functional testing.

The yaw servo was tested without anomaly. The pitch servo was impact damaged. Once the shaft and bracket were straightened the unit tested without anomaly. The roll servo was impact damaged with a displaced spring bar. Once the bar was repositioned, the unit tested without anomaly. The trim servo was impact damaged and did not pass functional tests for manual and auto trim.

The roll, yaw, and trim servo mounts were examined and tested. The roll servo mount tested within limits. The yaw servo mount tested one pound beyond limits. The trim servo tested one pound beyond limits.

The altitude preselector was impact damaged and could not be functionally tested. Non-volatile memory recovered from the unit indicated the last altitude selected was 27,000 feet with a vertical speed descent of 500 feet per minute. AIR TRAFFIC CONTROLN2428Q received ATC handling by ASE ATCT, ASE approach, two radar controllers at ZDV, three radar controllers at ZAB; R16, R15, and R87, and two radar controllers at ZFW sector R93.

N2428Q reported an equipment issue, and also exhibited numerous altitude deviations and a course deviation. No information regarding the equipment issues or the multiple altitude and course deviations was passed between controllers during the transfer of radar identification. Federal Aviation Administration Order (FAAO) 7110.65, Air Traffic Control, paragraph 5-4-3b4, Transfer of Radar Identification, Methods, states in part:

Advise the receiving controller of pertinent information not contained in the data block or available flight data unless covered in an LOA or facility directive. Pertinent information may include:

(a) Assigned heading.

(b) Speed/altitude restrictions.

(c) Observed track or deviation from the last route clearance.

(d) Any other pertinent information.

During the period leading up to the accident, moderate, severe, and extreme levels of precipitation were present and indicated on the controller's radar presentation. As a result of the weather conditions, numerous aircraft, including the accident aircraft, were requesting deviations from their filed flight plan routes to avoid the weather. The tops of the weather cells were being reported at 41,000 to 43,000 feet.

FAAO 7110.65, Air Traffic Control, paragraph 2-6-4a, Weather and Chaff Services, requires that air traffic controllers issue pertinent information on weather and chaff areas by defining the area of coverage in terms of azimuth (by referring to the 12-hour clock) and distance from the aircraft or by indicating the general width of the area and the area of coverage in terms of fixes or direction from fixes. Paragraph 2-6-4g states in part that when requested by the pilot, provide radar navigational guidance and/or approve deviations around weather or chaff areas. Paragraph 2-6-4g states:

When requested by the pilot, provide radar navigational guidance and/or approve deviations around weather or chaff areas. In areas of significant weather, plan ahead and be prepared to suggest, upon pilot request, the use of alternative routes/altitudes.

1. An approval for lateral deviation authorizes the pilot to maneuver left or right within the limits of the lateral deviation area.

In the radar data block of N2428Q, "DR" indicates that the aircraft is authorized to deviate to the right of the filed route of flight.

Automated information transfer (AIT) procedures utilizing en route fourth line data block free text are to be used within and between en route ATC facilities as defined in a facility AIT directive and letter of agreement.

At 1615, the ZAB R87 controller initiated a transfer of control to the ZFW R93 controller. At 1617 N2428Q checked in with the ZFW R93 controller at FL260 climbing to FL270 and advised the controller that he was in a turn for weather avoidance. The controller did not provide information on weather in the area because block 4 of the radar data block indicated "DR" for deviating right for weather. The controller stated that since N2428Q was already deviating, he did not issue weather to the aircraft because he thought the pilot was "obviously" aware of it.

At 1625, a position relief briefing began at the ZFW R93 position. The position relief briefing took four minutes to accomplish. During the position relief briefing, the controller being relieved was busy with multiple intra-facility coordination requirements, responding to numerous requests for deviation and numerous aircraft transfer of control actions/handoff to adjacent sectors. ZFW sector 93 did not have a radar associate coordinator position staffed.

There were no radio transmissions or coordination recorded at the ZFW R93 position for the next 50 seconds. No weather information was provided to N2428Q or any other airplane during this time. At 1630 the oncoming ZFW R93 controller asked N2428Q if the pilot "was going to go north of that weather there." The pilot responded that he was trying to "go through a window." Fifty seconds later, noting that N2428Q was climbing above his assigned altitude of FL270, the R93 controller asked the pilot 3 times if he needed a higher altitude. The pilot did not respond.

The controller who had previously been on at the ZFW R93 position remained in the area after being relieved and, noting the flight deviation of N2428Q, opened the D93 position to assist the R93 controller. At this time the controller-in charge (CIC) was also monitoring the developing situation from an adjacent control position

At 1632, the R93 controller advised N2428Q that he was in the middle of moderate to extreme precipitation and once again asked the pilot if he needed a different altitude. The pilot did not respond.

After observing N2428Q climb and then begin to descend, the R93 controller coordinated with the Lubbock low sector controller, sitting next to her, as N2428Q was about to depart her airspace and enter the airspace of the Lubbock low sector. While she was coordinating with the Lubbock sector controller, a single "MAYDAY" transmission was made. Although the MAYDAY transmission was recorded on the frequency, the controller stated that she did not hear the MAYDAY transmission. Immediately after the pilot transmitted MAYDAY, the controller asked N2428Q to say altitude. A pilot responded "nineteen."

According to the FAA Official Guide to Basic Flight Information and ATC Procedures; the Aeronautical Information Manual (AIM), chapter 6, Emergency Procedures, Section 3; Emergency and Distress Procedures, paragraph 6-3-1; Distress and Urgency Communications, states:

a. A pilot who encounters a distress or urgency condition can obtain assistance simply by contacting the air traffic facility or other agency in whose area of responsibility the aircraft is operating, stating the nature of the difficulty, pilot's intentions and assistance desired. Distress and urgency communications procedures are prescribed by the International Civil Aviation Organization (ICAO), however, and have decided advantages over the informal procedure described above.

b. Distress and urgency communications procedures discussed in the following paragraphs relate to the use of air ground voice communications.

c. The initial communication, and if considered necessary, any subsequent transmissions by an aircraft in distress should begin with the signal MAYDAY, preferably repeated three times. The signal PAN-PAN should be used in the same manner for an urgency condition.

d. Distress communications have absolute priority over all other communications, and the word MAYDAY commands radio silence on the frequency in use. Urgency communications have priority over all other communications except distress, and the word PAN-PAN warns other stations not to interfere with urgency transmissions.

The AIM, chapter 6, Emergency Procedures, Section 3; Emergency and Distress Procedures, paragraph 6-3-2; Obtaining Emergency Assistance, paragraph a3a states in part:

Transmit a distress or urgency message consisting of as many as necessary of the following elements, preferably in the order listed:

If distress, MAYDAY, MAYDAY, MAYDAY; if urgency, PAN-PAN, PAN-PAN, PAN-PAN.

FAAO 7110.65, Air Traffic Control and the AIM pilot controller glossary define MAYDAY as the international radiotelephony distress signal. When repeated three times, it indicates imminent and grave danger and that immediate assistance is requested.

Twenty three seconds after N2428Q responded to the altitude query, a pilot on the frequency asked if the controller had heard the MAYDAY call followed by a transmission by AAL1536 stating that he believed he heard a MAYDAY call as well.

After several unsuccessful attempts by the R93 controller to contact N2428Q and a request to Alaska Airlines flight 670 to attempt to contact N2428Q, the pilot of N2428Q reported "28Q spinning" at 1635. The R93 controller acknowledged N2428Q's call. An unidentified pilot on the frequency asked if N2428Q could see the ground or the horizon. The R93 controller asked N2428Q if the pilot could see the ground. There was no further response from N2428Q.

Additional details and figures are available in the Air Traffic Control Factual Report available in the public docket.