Accidents: July 2021

 - July 1, 2021, 9:00 AM

Preliminary Reports

Four Fatalities in Mississippi Approach Accident

Mitsubishi MU-2B-60, May 4, 2021, Hattiesburg, Mississippi – One occupant of the house and all three on board the airplane were killed when the twin-engine turboprop crashed into a home while attempting a GPS approach to Hattiesburg’s Bobby L. Chain Municipal Airport.  Two other people in the home suffered minor injuries.  Much of both the structure and the aircraft, including its instrument panel, were consumed by the ensuing fire.

The flight had departed from Wichita Falls, Texas just over two hours earlier on an IFR flight plan to Hattiesburg and was cleared for the RNAV approach to Runway 13.  ADS-B position data logged during the approach showed that the airplane flew to the initial approach fix, executed the procedure turn, and entered the final approach segment.  The last data point was recorded about 3.8 miles from the runway’s approach end, 1.6 miles from the accident site, at an altitude of 1,475 feet msl.  Investigators found the landing gear down and the flaps extended to 20 degrees.

The instrument-rated private pilot, whose second-class medical application filed nearly a year before the accident reported 7,834 hours of flight experience, had completed a flight review in the accident airplane on November 13, 2020 and the required model-specific recurrent training the following day.  Before buying the accident airplane in February 2012, he had owned an MU-2F model.

Tennessee Departure Crash Claims Seven

Cessna 501 S/P, May 29, 2021, Smyrna, Tennessee – Seven members of a Nashville-area church were killed when their Citation I crashed into Percy Priest Lake moments after takeoff.  The flight was bound for Palm Beach County (Lantana) Airport in Florida.  Recovered ADS-B data showed that the jet made a climbing right turn to 2,900 feet before descending to 1,800 and climbing back to 3,000 feet, then descending rapidly into the lake.  Ceilings in the vicinity were overcast at 1,300 feet.

Initial reports did not make clear who was at the controls.  One occupant, a co-owner of the company to which the jet was registered, held a CE-500 type rating but had not held a current medical certificate since 2019.  Another held a private pilot certificate with instrument and multi-engine ratings and a current medical, but no type ratings.  None of the others appear to have held pilot qualifications.

Final Reports

Unforeseen Medical Crisis Implicated in Firebombing Accident

Kawasaki Heavy Industries BK-117, August 17, 2018, Ulladulla, New South Wales, Australia – The ATSB concluded that sudden incapacitation from an undiagnosed medical condition was most likely responsible for the loss of the firefighting helicopter and its pilot.  The pilot was killed and the helicopter destroyed after the aircraft diverged from its planned course, allowing the fire bucket and long line to become entangled in trees.  Post-mortem examination led investigators to conclude that the pilot suffered from lymphocytic myocarditis, a condition “capable of causing sudden impairment or incapacitation” for which “There are no risk factors for the development … and it cannot be detected by medical screening.”  The pilot also had established coronary heart disease which was “being effectively managed by medication.”

The accident occurred on the pilot’s third flight of the day, dropping water collected from a nearby dam on a fire on Plot Road, Woodburn.  The bucket fill was uneventful, but shortly afterwards the helicopter went off course.  Autopsy revealed an area of acute inflammatory change in the pilot’s cardiac muscle, likely due to a previous viral infection, as well as confirmatory evidence of documented coronary heart disease.

Momentary Lapse Doomed King Air

Beechcraft B300, June 30, 2019, Addison, Texas – The pilot’s brief application of left rather than right rudder after losing thrust in the left engine caused a catastrophic loss of control at low altitude, resulting in the destruction of the aircraft with the loss of all on board.  The pilot, co-pilot, and eight passengers were killed after the airplane rolled over and crashed inverted into a hangar 17 seconds after takeoff.  In a finding of probable cause published on May 18, the NTSB also cited the 71-year-old pilot’s failures to lower the nose to maintain airspeed and raise the landing gear after losing the critical engine as having contributed.  The entire accident sequence lasted just 11 seconds from the first indication of loss of thrust to the moment of impact, making the lack of any discussion of emergency procedures prior to takeoff also potentially significant.

While not required, the King Air was equipped with a cockpit voice recorder (CVR).  The recording did not capture callouts from any of the applicable checklists (before engine start, engine starting, before taxi, or before takeoff).  The crew obtained the current ATIS information at 8:26 and received an IFR clearance to the Albert Whitted Airport in St. Petersburg, Florida at 8:30.  “A noise similar to an engine starting” was recorded just before 9:03, the second engine 16 seconds later.  They received clearance to taxi to Runway 15 at 9:05 and takeoff clearance at 9:09:41.

The noise of increasing propeller speed was heard 30 seconds later, and at 9:10:25 the co-pilot said “Airspeed alive.”  No V-speeds were called out at any point during the takeoff roll.  The NTSB’s sound spectrum and performance analyses concluded that rotation occurred at 9:10:32 at 102 knots airspeed – eight knots below the reference speed for those conditions – and liftoff two seconds later at 105 knots, 12 knots less than the appropriate takeoff safety speed, after a ground roll of 1,900 feet.  Witnesses on the ramp described the rotation as “steep,” consistent with other pilots’ descriptions of the accident pilot’s “aggressive” technique.

Six seconds after liftoff, the pilot asked, “What in the world?” as the sound of the propellers’ rpm began diverging.  In the next three seconds, the CVR recorded the sounds of a click, the stall warning, and the co-pilot saying “You just lost your left engine.”  The airplane began turning left but continued to climb.  A warning chime and another click followed, and the performance study calculated that the airplane began rolling left at 9:10:45.   It reached its maximum altitude of 100 feet two seconds later as the stall warning sounded again, followed by three “bank angle” annunciations.  Airspeed decayed to 85 knots, 11 below VMC, and the rate of left roll increased from 5 to 60 degrees per second.  The stall warning continued until impact at 9:10:51. 

The performance study found that the yaw observed in airport surveillance footage implied a rudder deflection of 11 degrees nose-left two seconds after the loss of thrust, neutralized two seconds later and then reversed to 20 degrees nose-right.  The cause of the power loss could not be determined.  Impact signatures, including rotational scoring on the stators and power turbine rotating components, showed that both engines were operating at impact.  The lack of checklist use, which the pilot’s business partner said was characteristic, raised the possibility that he’d neglected to set the friction locks, allowing the power control to slide back to the idle stop.  A sound test in another B300 cockpit found this made a click similar to that captured by the CVR.

The 28-year-old co-pilot flew with the pilot frequently, but was not type-rated in the B300 and not allowed to take the controls with passengers on board.  Investigators conjectured that this inhibited him from intervening during the brief interval the airplane remained controllable.

Zero-Flaps Landing Ends in Tail Strike

Challenger 605, February 23, 2020, Calgary International Airport, Calgary, Canada – The Canadian Pacific Railway corporate jet sustained significant damage after briefly pitching up, lifting off, and striking its tail during a no-flaps landing.  There were no injuries to any of the three crew members or ten passengers, but the strike broke off the airplane’s fuel drain mast and abraded the tail fairing’s lower skin.  The nose gear’s subsequent contact with the runway caused overload damage that included deformation of the left and right nose gear torque box structure and adjacent lower fuselage skins as well as damage to several lower front fuselage frames.  The TSB found that the crew responded appropriately to a “FLAPS FAIL” warning during approach, but failed to note the corresponding cautions in the Quick Reference Handbook (QRH) recommending nose-down control pressure prior to use of reverse thrust.

The flight from the Palm Beach (Florida) International Airport in the U.S. was uneventful until the initial descent into the Calgary area.  A “FLAPS FAIL” message appeared immediately after the crew selected “flaps 20.”  They requested and received delaying vectors to run the QRH flap failure checklist and prepare for a no-flaps landing on Runway 17R at an approach speed of 155 knots, 30 knots above the normal reference speed.  They touched down 3,000 feet beyond the threshold at 154 knots.  Two seconds after the nose gear touched down, the pilot flying deployed the thrust reversers and applied maximum reverse thrust.

The nose gear lifted off the runway 4.5 seconds later as the airplane pitched up to 13 degrees nose-high, reaching a maximum of 16.9 degrees as the pilot flying applied forward pressure and deselected reverse thrust.  The airplane banked slightly to the right and the left main gear briefly left the runway.  The stick pusher activated less than a second after the tail hit the runway, and despite countervailing nose-up control pressure by the pilot, the nose fell by at least 15 degrees per second until the nose gear struck the runway.  The jet slowed and was able to taxi to parking.  The flap failure was traced to corrosion in a flexible drive shaft due to moisture incursion, possibly from holes punched in the outer sheath during installation of its data plate.