Thursday, October 19, 2017
Transport Canada - Aviation Safety Letter RECENTLY RELEASED TSB REPORTS

RECENTLY RELEASED TSB REPORTS

TSB Final Report A00C0099—Loss of Control—Collision with Level Ice

Note: While this report is not recent, it is included as a special insert on the whiteout phenomenon at the request of the Transportation Safety Board of Canada (TSB) as the Board has noticed an increase in recent whiteout occurrences. —Ed.

On May 20, 2000, a Bell 206L LongRanger helicopter was on a charter flight under day VFR, from a site on the sea ice near Lowther Island, Nun., to Resolute Bay, Nun., about 40 NM east-northeast of Lowther Island. On board were a pilot and two passengers who had been conducting scientific research on the behaviour of polar bears in the sea ice environment. At about 22:05 Central Daylight Time (CDT), the pilot lifted off from the sea ice, heading toward Lowther Island to take advantage, during takeoff, of the visual reference provided by the island’s terrain features. At about 400 ft above the ice and 65 kt, the pilot turned the helicopter to the right toward Resolute Bay. During the turn, he realized that he no longer had sufficient visual references because of whiteout conditions. He began a left turn back toward Lowther Island and the visual references on the island. While in the left turn, the pilot lost control of the helicopter, and it descended and collided with the ice surface. Although the pilot and the passengers were wearing their seat belts and shoulder harnesses, they were all ejected from the fuselage as it disintegrated during the impact sequence. Both passengers sustained fatal injuries; the pilot sustained serious injuries. The helicopter was destroyed.

Bell 206L LongRanger helicopter

Other factual information
The helicopter was equipped for operations under IFR, although the operator employed it only under VFR. The helicopter contacted the level ice surface in a nose-low, steep left turn, and the wreckage was distributed along a straight path approximately 600 ft long. There was no indication of any pre-impact aircraft system malfunction or airframe failure.

The 45-year-old pilot held a Canadian commercial helicopter pilot licence that was restricted to day flying only and valid for several types of helicopters, including the Bell 206L. He held a Class 3 instructor rating and had accumulated 8 120 hr of total flying time, mostly on the Bell 206L and similar helicopters. In addition, he had accumulated 15 hr in simulators and received 10 hr of dual instrument instruction during training for his instructor rating in late 1998. He did not have an instrument rating, nor was one required by regulation. During the previous 90 days, he had flown 145 hr, including 87 hr during the previous 30 days. This section is included here to illustrate that a whiteout occurrence can happen to a very experienced pilot. —Ed.

The weather at Resolute Bay, 35 mi. northeast of the occurrence location, was reported as follows: winds 260° true at 4 kt, visibility 10 SM, a broken cloud layer at 900 ft, temperature -15°C, dewpoint -18°C, and altimeter setting 29.77 in. of mercury. A Twin Otter aircraft had departed from the helicopter’s location about 25 min before the accident. It was reported that the weather had deteriorated during the Twin Otter’s time on the ground and that the local conditions were overcast, with a layer of stratus cloud at about 2 000 ft; the visibility was about 6 to 8 mi., and there was very little definition to surface features. At the time of the occurrence, the sun was constantly above the horizon, providing 24-hour daylight.

Regulations for VFR flights in uncontrolled airspace required that the aircraft be operated with visual reference to the surface and, for helicopters operating below 1 000 ft above ground level (AGL), that the aircraft be operated in flight visibility of not less than 1 mi. and clear of cloud. When flying VFR, pilots rely on visual orientation cues, such as the natural horizon and surface references, to maintain the desired attitude of the aircraft. The minimum weather conditions specified in the regulations normally permit pilots to see these orientation cues.

The Transport Canada Aeronautical Information Manual (TC AIM), section AIR 2.12.7, describes whiteout as an extremely hazardous visual flight condition. Whiteout occurs over an unbroken snow cover and beneath a uniformly overcast sky. Because the light is diffused, the sky and terrain blend imperceptibly into one another, obliterating the horizon. The horizon, shadows, and clouds are not discernible, and sense of depth and orientation is lost; only very dark, nearby objects can be seen. The real hazard in whiteout is that pilots do not suspect the phenomenon because they may be in clear air. In many whiteout accidents, pilots have flown into snow-covered surfaces unaware that they have been descending, and confident that they could see the surface. Consequently, when pilots encounter the whiteout conditions described above, or even suspect they are in such conditions, they should immediately climb if at low level, or level off and turn toward an area where sharp terrain features exist. Pilots should not continue the flight unless they are prepared to cross the whiteout area using instruments and have the training and qualifications to do so.

Analysis
Because the pilot was flying VFR, he relied on visual orientation cues, such as the natural horizon and surface references, to maintain the desired attitude of the aircraft. The existing weather conditions were better than those specified by regulation for VFR operations; however, when external visual cues became obscured by whiteout conditions, the pilot was subject to disorientation with respect to the relationship between the aircraft and the surface because there were no distinguishing features. To counteract this disorientation, it is necessary to revert to flight instruments to determine and maintain aircraft attitude. However, the pilot was not instrument rated, was unable to regain visual reference, and was therefore unable to maintain control of the helicopter.

Findings as to causes and contributing factors

  1. Whiteout conditions impaired the pilot’s visual reference to the surface. As a result, he was unable to maintain control of the helicopter.
  2. The seat belts and shoulder harnesses failed because the fuselage disintegrated.

Findings as to risk

  1. The survival kit would have been extremely difficult or impossible to open for a survivor with hand or arm injuries, especially in the existing cold weather.
  2. The emergency locator transmitter (ELT) antenna cable separated during impact, rendering the ELT partially ineffective.

Safety action taken
The manufacturer of the survival kit conducted field tests with the kit and has upgraded the survival equipment and made the kit easier to open. The company used Velcro on its larger survival kits, rather than snap fasteners, and is replacing the snap fasteners on the kit involved in this occurrence with Velcro. The laces on the inner flaps have also been replaced with Velcro. A utility knife attached with a lanyard has been added to permit piercing and cutting of the inner seals, and an instruction card explaining the opening procedure has been included.

TSB Final Report A04P0422—Drive-Belt Failure and Collision With Terrain

On December 28, 2004, a Robinson R44 Raven II helicopter landed at the Cranbrook, B.C., airport at 12:37 Mountain Standard Time (MST). There, the pilot filled the fuel tanks to capacity and obtained weather and flight-planning information. The helicopter departed Cranbrook at 13:43 MST for Revelstoke, B.C., evidently following the VFR route north along the Columbia River, towards Fairmont Hot Springs. The flight was expected to take 2 hr. At 14:15 MST, the helicopter struck steep terrain 33 NM north-northwest of Cranbrook, at the 4 200-ft level in a mountainous region. The pilot was fatally injured and the helicopter destroyed by impact forces and a severe post-crash fire.

Drive-Belt Failure and Collision With Terrain

Findings as to causes and contributing factors

  1. Galling on the engine-cooling fan taper-fit joint within the previous few hours of flight operations introduced vibration to the belt-drive system, which in turn caused the misalignment of the belts within the sheave grooves and led to two vee-belts running off the sheaves in flight.
  2. The sudden loss of vee-belt tension caused the remaining two vee-belts on the driving sheave to slip, leading to a rapid loss of main rotor RPM. This, in turn, prevented the pilot from avoiding the trees and led to a collision with the terrain and the destruction of the helicopter.

This close-up photo shows the uneven wear and belt slip on the engine pulley sheaveThis close-up photo shows the uneven wear and belt slip on the engine pulley sheave

Findings as to risk

  1. The engine-cooling fan taper-fit shaft and socket joint is subject to galling damage, which imparts vibration to the vee-belts and sheaves, a known factor in vee-belt failure, misalignment and loss.
  2. The wear found in the exhaust valve guides for cylinders number 3 and 5 was excessive for their time in service and indicated a deviation from manufacturing quality control.

TSB Final Report A05W0137—Collision with Terrain

On July 6, 2005, the pilot of a Piper PA-18 aircraft departed Cooking Lake Airport, Alta., at approximately 11:30 Mountain Daylight Time (MDT) and landed at the Chipman, Alta., airfield, where a passenger boarded. They departed at 12:12 MDT for the last day of two weeks of aerial photography. The weather was observed to be clear and the winds nearly calm when the PA-18 departed Chipman.

At approximately 18:10 MDT, a farmer found the aircraft wreckage in a hay field, 9 NM west of Andrew, Alta. The aircraft had struck the ground at an extreme nose-down, left-wing-low attitude, and was substantially damaged. Both occupants sustained fatal injuries. There was no post-impact fire.

Collision with Terrain

Finding as to causes and contributing factors

  1. For undetermined reasons, the aircraft departed controlled flight and struck the ground.

Findings as to risk

  1. The tight installation of the emergency locator transmitter (ELT) antenna cable resulted in the disconnection of the cable from the ELT at impact, and there was no effective ELT signal.
  2. The pilot did not file a flight plan or a flight itinerary, with the result that the rescue of possible survivors would have been delayed.
  3. Procedures for the delegation of management authority in the absence of key company personnel were incomplete, resulting in ineffective flight following and emergency response.

Other findings

  1. Investigators were not able to determine why the aircraft departed from controlled flight. The aircraft was not fitted with a flight recording device, which may have allowed investigators to reconstruct the circumstances that led to the accident.
  2. A rear control stub cover could not be found in the wreckage.

Safety action taken
The company has developed a delegation system to ensure that there is always someone of authority available. Checklists have been drafted for the management positions, and they are to be used by delegated individuals in the absence of management personnel. These measures will ensure that acting managers are assigned on a consistent basis and that they are aware of their responsibilities.

The flight following system has been strengthened by informing pilots of the necessity to submit a comprehensive flight itinerary or flight plan before each flight. The telephone answering service will continue to serve as a message board for delegated individuals and will not be used as the primary flight following system. Acting managers will assume responsibility through use of the delegated duties checklist. Overdue alerting will be more rigidly followed.

TSB Final Report A05O0142—Difficulty to Control

On July 10, 2005, a Bell 204B helicopter was conducting a survey job at Marathon, Ont., with a crew comprising a pilot and an aircraft maintenance engineer (AME). They departed Marathon on the day of the occurrence at about 09:00 Eastern Daylight Time (EDT) to return to Sudbury, Ont., flew to Wawa, Ont., for fuel, and continued to Sudbury. The helicopter was on final approach to Sudbury Airport at about 11:45 EDT with the wind from the south-southwest at less than 5 kt. When the collective was raised and the cyclic pulled aft to reduce the sink rate and airspeed, the helicopter yawed to the right, and the pilot was unable to correct with the left pedal. The collective was lowered and the cyclic pushed forward to increase the airspeed. The helicopter returned to a normal flight condition at 60 knots indicated airspeed (KIAS), and the pedals were neutral. The pilot aborted the approach and flew a left-hand downwind approach for Runway 22.

During the second approach, when the collective was raised to slow the sink rate, there was a thump and the left pedal went to full deflection. The pilot declared an emergency, then flew several circuits to determine the best way to make a landing. The helicopter flew well at 40 KIAS, and the heading could be controlled by adjusting the throttle. The helicopter was lined up with the runway about 2 mi. back on a shallow approach and crossed the runway threshold at a height of 3 to 5 ft and about 40 KIAS. It touched down gently at approximately 30 KIAS with 80 percent rotor rpm and skidded about 90 ft before coming to a stop. There were no injuries.

Speed rig and cables as foundSpeed rig and cables as found

Properly lock-wired speed rigProperly lock-wired speed rig

Findings as to causes and contributing factors

  1. The tail rotor pitch change cable speed rigs were not lock-wired in accordance with approved methods. As a result, one cable speed rig came undone, and tail rotor authority was lost.
  2. The independent control inspection was not carried out in accordance with the standards described in the Canadian Aviation Regulations (CARs) or relevant Airworthiness Notice (AN), and the missing lock wire was not detected.

Findings as to risk

  1. The pilot conducting the independent inspection was qualified and had received elementary maintenance training that included independent control checks. However, without specific training on maintenance procedures and standards, there is an increased risk of missing maintenance-related deficiencies.

Safety action taken
Following the occurrence, the operator conducted a training program for maintenance and operations personnel. The aim of the program was to refresh all personnel in the proper locking of turnbuckles and aircraft components in general, and to educate all personnel on what to look for when conducting an independent inspection on each company-operated aircraft. The AME who was involved in this occurrence developed and delivered the program to employees.

The TSB is concerned that companies using pilots to conduct independent inspections may not have developed training programs of sufficient detail to prevent similar occurrences.

TSB Final Report A05P0189— Collision with Terrain

On July 28, 2005, a Raytheon Beechcraft King Air 200 departed Vancouver, B.C., at 08:24 Pacific Daylight Time (PDT) for a VFR flight to Smithers, B.C., with a crew of two on board. The aircraft did not arrive at its destination, and a search was commenced later that same day. The aircraft was found on July 30, 2005. The crash site was in a narrow canyon at an elevation of about 3 900 ft above sea level (ASL), in an area of steeply rising terrain. Both occupants were fatally injured. A post-crash fire destroyed most of the aircraft. The emergency locator transmitter (ELT) was destroyed in the fire and no signal was detected. The crash occurred at about 08:40 PDT.

Collision with Terrain

Findings as to causes and contributing factors

  1. The aircraft was flown up a narrow canyon into rapidly rising terrain for reasons that could not be determined. The aircraft’s proximity to terrain and the narrowness of the canyon precluded a turn, and the aircraft’s climb rate was insufficient to clear the rising terrain.
  2. The pilot decision-making training received by the crew members was ineffective because they were unprepared for the unique hazards and special operating techniques associated with flying low in mountainous terrain.

Finding as to risk

  1. The company operations manual (COM) gave no guidance to the crew for the operation of a VFR flight, except for the provision that it should not be conducted closer to obstacles than 500 ft vertically and horizontally.

TSB Final Report A05O0204—Aircraft Loss of Control—Collision with Terrain

On September 10, 2005, a Pezetel SZD-50-3 Puchacz glider was flying in the vicinity of Ronan Field (44°02’30” N, 079°50’42” W) near Loretto, Ont., on a pleasure flight with two pilots on board. After approximately 45 min of flight, the glider was about 1 000 ft above ground level (AGL) and appeared to be approaching the circuit. It then entered a spin and rotated about three times before disappearing behind trees. At approximately 16:05 Eastern Daylight Time (EDT), the glider struck the ground in a steep, nose-down attitude. The aircraft was destroyed, and the two pilots were fatally injured.

Aircraft Loss of Control-Collision with Terrain

Findings as to causes and contributing factors

  1. The glider inadvertently entered a spin at approximately 1 000 ft AGL and did not recover from the spin before ground impact.
  2. The glider pilots likely did not execute the proper spin-recovery technique.

TSB Final Report A05C0222—Runway Excursion

On December 26, 2005, an Airbus A319-112 was landing at Winnipeg International Airport, Man., in darkness at 18:35 Central Standard Time (CST). An instrument landing system (ILS) approach to Runway 13 was flown using the autopilot. At approximately 80 ft above ground level (AGL), the captain disengaged the autopilot and manually completed the approach and landing.

The aircraft touched down firmly approximately 1 600 ft from the runway threshold and well-left of the runway centreline. During the rollout, the left landing gear tracked briefly outside of the runway edge lights on the left side of the runway. Two of the runway edge lights were broken. One tire of the left wheel set sustained a cut and was replaced. There was no other damage to the aircraft, and there were no physical injuries.

Overhead view of Runway 13 and aircraft trajectoryOverhead view of Runway 13 and aircraft trajectory

Findings as to causes and contributing factors

  1. The captain aligned the aircraft with the runway without compensating for crosswind, allowing the aircraft to drift off centreline. After touchdown, the aircraft’s left landing gear tracked off the runway.
  2. It is likely that one or more of the effects of the vision correction used by the pilot flying interfered with his ability to effectively use the visual references available to land.

Other finding

  1. The cockpit voice recorder (CVR) was not disabled following the occurrence, and the data were overwritten. Consequently, CVR information relevant to the occurrence was not available to TSB investigators.

Safety action taken
Following the incident, the operator issued a flight operations bulletin stating that "the use of auto land should be considered for all approaches in marginal conditions."

TSB Final Report A06Q0091—Engine Failure

On June 7, 2006, a Bell 206L-3 was on a VFR flight from La Tuque, Que., to Val-d’Or, Que. Approximately 20 min after takeoff, at about 08:10 Eastern Daylight Time (EDT) and at 2 000 ft above sea level (ASL), the needle on the engine oil-pressure gauge started to fluctuate. As a precaution, the pilot landed the aircraft in a marsh and shut down the engine. After conducting a pre-flight inspection, the pilot started the engine and took off with the intention of landing on a road 1 km away. Just before the helicopter reached the road, there was a fluctuation in the engine oil pressure and engine torque. Right after that, there was an explosion and the engine stopped. The pilot did an autorotation that ended with a hard landing on the road. The helicopter was heavily damaged. The pilot was alone on board and was not injured.

First-stage wheel damage due to overspeedFirst-stage wheel damage due to overspeed

Findings as to causes and contributing factors

  1. The area adjacent to bearings 6 and 7 had exceeded a temperature of 900°C. The bearings were destroyed for undetermined reasons, causing an engine failure.
  2. Moving the helicopter towards the road when the engine was showing signs of malfunction contributed to the failure of bearings 6 and 7.
  3. During the autorotation, the helicopter was not levelled at the time of the landing, which resulted in a hard landing.

Finding as to risk

  1. The procedure recommended in the flight manual suggests a less serious problem if engine oil pressure is fluctuating within the limits and the gauge is showing a normal oil temperature. Consequently, a pilot could decide to continue the flight with a defective engine oil-circulation system, which could cause the engine to fail or malfunction.

TSB Final Report A06A0092—Collision with Terrain

On September 17, 2006, an amateur-built VariViggen aircraft departed Bangor Airport, Maine, United States, at 17:11 Atlantic Daylight Time (ADT), on a non-stop VFR flight to Goose Bay, N.L. The aircraft wreckage was located on September 22, 2006, in a heavily wooded area about 9 NM east of Plaster Rock, N.B. The pilot had been fatally injured in the crash, and the aircraft was destroyed.

VariViggen aircraft

Findings as to causes and contributing factors

  1. The wing tanks had become contaminated with water; however, the source of the water contamination could not be determined.
  2. The aircraft did not have fuel tank drains to allow for easy pre-flight inspection of the entire fuel system.
  3. The engine stopped when water, transferred from the wing tanks to the main tank, settled in the main fuel tank and was subsequently delivered to the engine.
  4. The flight was conducted at a relatively low altitude, limiting the pilot’s opportunity to cope successfully with the engine stoppage.

Findings as to risk

  1. Because the flight plan had not been activated, Canadian air traffic control (ATC) and search and rescue (SAR) authorities were not aware of the flight, and the initiation of the search was delayed for three days.
  2. The emergency locator transmitter (ELT) signal was not detected, primarily because the antenna had been broken during the accident.

Safety action taken
This report shows that there are VFR aircraft proceeding from the United States to Canada without the protection of SAR notification that an activated flight plan affords. On November 27, 2006, the TSB sent an Aviation Safety Advisory (A060042) to Transport Canada. In the advisory, it was suggested that, in conjunction with NAV CANADA and the U.S. Federal Aviation Administration (FAA), Transport Canada take steps to ensure that pilots comply with the requirement to file VFR flight plans for transborder flights and ensure that filed transborder VFR flight plans are automatically identified and activated.

Transport Canada published an article titled “Transborder Flights Without a Flight Plan—Revisited” in the Aviation Safety Letter (ASL) 1/2007. A copy of this article may be obtained at www.tc.gc.ca/CivilAviation/publications/tp185/1-07/menu.htm.

Scaled Composites has advised VariViggen owners to install low-point fuel tank inspection drains in the wing tanks before the next flight. Scaled Composites has produced and provided owners with plans for the drain installation, modifications to the aircraft flight manual (AFM) requiring fuel checks before every flight, and the method to be used when checking the fuel tanks for contamination. Scaled Composites has also sent a safety bulletin to the publishers of the Central States Newsletter, and the Experimental Aircraft Association Sport Aviation magazine, with a request to publish it in the next available edition of both publications.

 

This article was published by Transport Canada in TP 185 Issue 4/2008 -. Reprinted with permission

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