Accidents: April 2014

Preliminary Report: Pilots Safely Wrestle AStar to the Ground

Airbus AS350B3, Houlton, Maine, Jan. 17, 2014–Neither of the two AStar pilots was injured after a forced landing near the end of Runway 23 at Houlton International Airport (HUL). Operated by U.S. Customs and Border Patrol, the helicopter had departed HUL for a local nighttime training flight. During a takeoff near the end of the runway, at approximately 8:40 p.m. and with the copilot at the controls, both pilots heard a loud explosion from behind the cabin, followed by severe vibrations.

The helicopter quickly developed controllability problems, at which time the PIC took control. He noticed red lights on the warning panel but had insufficient time to identify them. With limited control, the pilot managed to set the helicopter down just beyond some snow banks at the end of the runway. As he shut down the engine, both pilots noticed a red glow against the snow. Despite the absence of any fire warning lights they assumed the helicopter was on fire and exited. The copilot tried unsuccessfully to douse the flames with a portable extinguisher. After arriving 10 minutes later, the local fire department put out the fire.

The PIC told investigators that throughout the event, he could not adjust the collective without inducing “extreme” attitude excursions, nor could he stabilize the helicopter to the point that he could roll off the power. After about 30 seconds the attitude excursions began to “calm down,” at which time he was able to land safely. Once the helicopter touched down, the PIC noted that the first warning lights he had seen were an amber eng chip light and the red gov light. After reviewing training materials later, the PIC was able to estimate that the other amber lights he had seen were the fuel (pressure) and door lights.

Preliminary Report: Twin Commander Accident Fatal to Four

Twin Commander 690C, Bellevue, Tenn., Feb. 3, 2014–A Commander 690C twin turboprop was destroyed when it crashed at 4:55 p.m. during an instrument approach to John C. Tune (JWN) Airport in Nashville, Tenn. The flight had originated from Great Bend, Kan., and the crew had just picked up the aircraft from a maintenance shop after a 150-hour inspection.

On arrival at JWN, the pilot missed the first attempt at the GPS Runway 2 approach and was vectored back for a second attempt. During the second attempt, the airplane veered to the left while on final approach, began a descent and turned to a heading of about 210 degrees before radar contact was lost. ATC received no distress calls. All four people aboard the aircraft died in the crash. JWN weather at 4:55 p.m. was reported as 800 feet overcast with five statute miles visibility.

The aircraft hit trees in a field adjacent to a building about nine miles south of JWN, creating an 11-foot-long, 11-foot-wide, six-foot-deep crater. Broken tree branches at the 50-foot level displayed 45-degree angled cuts and the airplane hit the ground inverted at about a 70-degree angle. A post-crash fire consumed most of the airframe. Portions of both outboard wings, the nose section, empennage and all flight control surfaces were located at the accident site. Neither powerplant displayed any obvious evidence of catastrophic failure and both were found intact but with fire damage. Both propellers displayed evidence of rotational scoring, with leading- and trailing-edge gouges consistent with rotation at the time of impact.

Preliminary Report: Helicopter Damaged During Training

Hughes 369D, Naples, Fla., Feb. 3, 2014–An MD500D operated by the Collier Mosquito Control District was substantially damaged during a practice 180-degree autorotation at Naples airport. Visual conditions existed at the time of the accident and neither the ATP-rated pilot nor the flight instructor aboard was injured.

The flight instructor reported that before the last practice “full down” autorotation, they performed two running landings, two stuck left pedal maneuvers, three stuck right pedal maneuvers, and eight successful autorotations in which the aircraft appeared to be performing normally. During the incident, as in the previous eight approaches, the helicopter responded the same during the flare, but this time suddenly lost altitude and contacted the ground. The instructor “quickly grabbed” the controls and landed the helicopter as it yawed 90 degrees to the right. The ATP-rated pilot, who had been undergoing annual proficiency training, said that two of the 180-degree autorotations to touchdown were performed successfully but that on the third one the helicopter’s tail hit the ground.

The ATP believed that the entry to the maneuver was normal and that before touchdown the helicopter was level and pointed largely into the wind, with the wind at most 10 to 15 degrees left of the nose and landing direction. He was at the target speed of approximately 60 knots indicated airspeed, and the rotor rpm was in the middle of the green arc. He initiated the flare about 50 feet above the ground to arrest the forward motion as he had done on the previous autorotations, but at some point during the flare he felt a bump as the tail hit the ground. He said he continued the procedure and arrested the forward motion, resulting in a normal touchdown with little forward motion. But the helicopter came to rest turned 60 degrees to the right of its intended direction.

A witness said that during the last approach the helicopter seemed to be descending more rapidly and aggressively than before. He said that when the helicopter was approximately 100 feet agl it nosed up aggressively as the tail struck the ground and came to rest with the main rotor still turning.

Subsequent examination showed impact damage to the tail-rotor blades. The tail-rotor driveshaft was also twisted and bent, as were the horizontal stabilizer and the forward and aft tail-rotor driveshaft couplings. The tail-rotor driveshaft dampener was distorted, and the tail-rotor output shaft on the transmission was bent.

Preliminary Report: King Air Accident Claims Pilot

Beechcraft King Air B100, Pearland, Texas, Feb. 19, 2014–The private pilot, the only occupant of the Part 91 aircraft, was killed during a missed approach from the Runway 32 GPS approach at Pearland. The airplane was registered to and operated by TDC Aviation of Wilmington, Del. The aircraft was in the process of circling to Runway 14 at 8:45 a.m. when it missed the approach and subsequently crashed. Weather was reported at 8:53 a.m. as wind from the south at eight knots, five miles visibility, mist, and an overcast at 300 feet.

Two witnesses reported hearing the airplane overhead but it was not visible through the low clouds. Three others, working in a nearby oilfield, reported seeing the airplane hit the ground nose first.

The impact created a crater with signatures consistent with a near vertical collision with terrain. The wreckage was highly fragmented and a post-crash fire destroyed most of the airplane.

Preliminary Report: Four Perish in Falcon 20

Dassault Falcon 20, Kish Island, Iran, March 3, 2014–All four people aboard the Falcon 20 were killed when the aircraft crashed 2.5 miles east of Kish Island. The aircraft was reportedly on a navigational equipment calibration flight at the time of the accident. Weather at that time is unknown.

Preliminary Report: BAe 748 Crashes in Sudan

British Aerospace BAe 748, Rubkona Airport, South Sudan, Feb. 17, 2014–One crewmember was killed and three others were seriously injured when the wing of a BAe 748 twin turboprop delivering humanitarian aid collided with two ground vehicles during the landing roll. The collision ignited a fire. According to reports, the International Organization for Migration had chartered the aircraft from 748 Air Services.

Preliminary Report: Brasilia Substantially Damaged in Accident

Embraer EMB-120 Brasilia, near Lukapa Airport, Lunda Norte, Angola, Feb. 25, 2014–The undercarriage, wings and engines of the Brasilia were substantially damaged when the twin turboprop made a forced landing on rough terrain after experiencing an unspecified engine problem en route to Dundo Airport. None of the 17 people aboard the aircraft was injured.

Preliminary Report: Antonov Accident Kills 11

Antonov An-26, near Grombalia, Tunisia, Feb. 21, 2014–Everyone on board the Antonov medical flight was killed when the turboprop twin crashed 20 miles from Tunis Carthage Airport. Reports said ATC received a message from the crew that the aircraft was experiencing engine problems just before the accident.

Preliminary Report: Twin Otter Crash Fatal to All Aboard

De Havilland Canada DHC-6 Twin Otter 300, northwest of Sandhikhark, Nepal, Feb. 16, 2014–The last radio contact with a Nepal Airlines Twin Otter was reported at 1:13 p.m. on a flight between Pokhara and Jumla, Nepal. The aircraft was declared missing not long after it failed to make its 1:45 p.m. arrival time at Jumla. Search-and-rescue located the aircraft the next morning at the 7,000-foot terrain level. The aircraft was destroyed, with no survivors.

Final Report: Fuel Exhaustion Blamed in Flight of Police Bell 206B

Bell 206B, Clarkson Valley, Mo., Oct. 15, 2010–Poor preflight planning, subsequent fuel exhaustion and the pilot’s mishandling of engine failure caused the crash of a Bell 206 operated by the Missouri State Highway Patrol, according to the NTSB. The sole-occupant pilot died in the crash, which occurred at 11 a.m. in visual weather conditions. Contributing to the accident, however, were medical conditions the pilot did not report on his FAA physical, any of which would likely have disqualified him from holding a medical certificate. Before the accident flight, the pilot had been flying with two other police officers on a traffic patrol that lasted almost two hours. He commented to one officer in the front seat that the flight would be shorter than usual because he needed to fly to Spirit of St. Louis (SUS) Airport for fuel. The officer in the front seat noticed that the helicopter’s fuel gauge indicated about halfway between E and 25 (approximately the quarter-tank point). He also told investigators he did not notice anything unusual about the way the helicopter seemed to be operating up to the point at which he and his partner were dropped off at the Arnold Police Department at approximately 11 a.m. The pilot told the trooper it would take him about 10 minutes to fly to SUS. The helicopter crashed less than 10 minutes after takeoff from the Arnold Police Department site.

Post-accident examination of the helicopter revealed no usable fuel on board and that the main rotor mast had separated as a result of overload stemming from mast bumping (contact between the main rotor hub and the rotor mast). Investigators noted no pre-impact mechanical anomalies that would have precluded normal operation of the helicopter. Mast bumping typically results from a low-G flight condition caused by the pilot’s pushing the cyclic control forward abruptly from either straight-and-level flight or after a climb. Pushing the cyclic forward abruptly is contrary to the appropriate actions for entering an autorotation, which are lowering the collective pitch control to the full down position, adding anti-torque pedal as needed to maintain heading, and applying aft cyclic as needed to maintain proper airspeed and rotor rpm.

Review of the pilot’s medical records indicated that he also had a history of depression, anxiety and obstructive sleep apnea. Each of these conditions had been documented and treated since 2007, although none was reported to the FAA on the pilot’s airman medical application in 2010 or earlier. Any of these conditions might have disqualified the pilot from obtaining an airman’s medical certificate. Post-mortem toxicological testing indicated that the pilot was taking alprazolam (an anti-anxiety medication) and venlafaxine (an anti-depressant). Alprazolam can aggravate obstructive sleep apnea, and venlafaxine can cause fatigue and dizziness. With his blood level of venlafaxine found to be higher than normal therapeutic levels, the Board noted, it was more likely that the side effect of dizziness had occurred and impaired the pilot’s performance.