Tuesday 6 August 2019

NEPAL: Tenzing–Hillary Airport The Most Dangerous Airport In The World

Tenzing–Hillary Airport, also known as Lukla Airport, is a small airport in the town of Lukla, in Khumbu, Solukhumbu District, Province No. 1, eastern Nepal.

A program titled Most Extreme Airports, broadcast on The History Channel in 2010, rated the airport as the most dangerous airport in the world for over 20 years.

The airport is popular because Lukla is the place where most people start the climb to Mount Everest Base Camp.

There are daily flights between Lukla and Kathmandu during daylight hours in good weather. Although the flying distance is short, rain commonly occurs in Lukla while the sun is shining brightly in Kathmandu.

High winds, cloud cover, and changing visibility often mean flights can be delayed or the airport closed. The airport is contained within a chain link fence and patrolled by the Nepali armed police or civil police around the clock.

The airport was built in 1964 under the supervision of Edmund Hillary, who originally intended to build the airport on flat farmlands. However, local farmers did not want to give up their land, so the airport was built at its current position.

Hillary bought the land from local Sherpas for US$2,650 and involved them in building the facilities.

It has been said that Hillary was unhappy with the runway's soil resistance, and that his solution was to buy local liquor for the Sherpas and ask them to perform a foot-stomping dance to flatten the land that served as the runway. The runway was not paved until 2001.

In January 2008, the airport was renamed in honor of Sherpa Tenzing Norgay and Sir Edmund Hillary, the first people confirmed to have reached the summit of Mount Everest, and also to mark their efforts in the construction of this airport.

The airport's paved asphalt runway is accessible only to helicopters and small, fixed-wing, short-takeoff-and-landing aircraft such as the De Havilland Canada DHC-6 Twin Otter, Dornier Do 228, L-410 Turbolet and Pilatus PC-6 Turbo Porter.

The runway is 527 m (1,729 ft) × 30 m (98 ft) with an 11.7% gradient. The airport's elevation is 9,334 ft (2,845 m).

The airport is used for passenger flights and for transporting most of the building materials and cargo to Lukla and other towns and villages to the north of Lukla, as there is no road to this region.

In the early morning, the wind is usually from the north-east, changing to a south-west wind from mid to late morning due to the action of the sun on the mountains to the north of Lukla.

The airport regularly closes from mid to late morning due to the strong south-west winds that create crosswind tailwinds. Consequently, flights are usually scheduled for the early morning.

Sudden loss of visibility preventing planes from landing under Visual Flight Rules (VFR) will result in the immediate closure of the airport with no warning.

Although the airport is available throughout the year, visibility problems close the airport 50% of the time during the monsoon season with a consequent cancellation of 50% of flights.

Due to the terrain and the low possibility of a safe go-around for a missed approach, there are no go-around procedures for this airport.

Tenzing–Hillary Airport is frequently referred to as the most dangerous airport in the world.

Arriving and departing aircraft must use a single runway, 06 for landing and 24 for takeoff. There is a low prospect of a successful go-around on short final approach due to the terrain.

There is high terrain immediately beyond the northern end of the runway and a steeply angled drop at the southern end of the runway into the valley below.

Due to the difficulties of successfully landing at the airport, the Civil Aviation Authority of Nepal sets high standards, for which only experienced pilots, who completed at least 100 short-takeoff-and-landing (STOL) missions, have over one year of STOL experience in Nepal and completed ten missions into Lukla with a certified instructor pilot, are allowed to land at the airport.

There are plans to construct five new helipads at the airport by 2020 and expand the terminal and runway.

On 15 October 1973, a Royal Nepal Airlines DHC-6 Twin Otter 300 (registration 9N-ABG) was damaged beyond repair on landing. The three crew and three passengers were unhurt.

On 9 June 1991, a Royal Nepal Airlines DHC-6 Twin Otter 300 (registration 9N-ABA) from Kathmandu crashed at the airport while attempting to land following an unstabilized approach in bad weather. The three crew and fourteen passengers escaped with injuries.

On 26 September 1992, a Royal Air Nepal Harbin Yunshuji Y-12-II (registered 9N-ACI) faltered during takeoff and was damaged beyond repair. All twelve passengers and two crew survived.

On 25 May 2004, while on approach to the airport, a Yeti Airlines DHC-6 Twin Otter 300 (registration 9N-AFD) from Kathmandu crashed into Lamjura Hill in heavy clouds. No passengers were on board; all three crew members were killed.

The Nepalese accident investigation committee concluded that the captain provided inaccurate information about his position to the Area Control Centre.[28]
On 1 October 2004, on landing at the airport, a Sita Air Dornier Do 228 suffered a collapse of its nose gear and slid along the runway, blocking it once it had come to rest. The airport was closed for two days.

On 30 June 2005, a Gorkha Airlines Dornier Do 228 skidded off the runway while attempting to land. The nine passengers and three crew suffered minor injuries. The aircraft was reportedly withdrawn from service and written off after the accident.

On 8 October 2008, Yeti Airlines Flight 103, a DHC-6 Twin Otter 300 (registration 9N-AFE) crashed on final approach and caught fire, killing eighteen passengers and crew. The aircraft's captain was the only survivor. Video of the incident showed inclement weather at the time of the incident.

On 12 October 2010, a Sita Air Dornier Do 228 (registration 9N-AHB) lost braking control and struck the wall-end of the runway during landing. All passengers and crew escaped injury; the aircraft's nose was damaged.

On 26 September 2013, an Air Dynasty helicopter (registration 9N-AEX) crashed when the rear rotor touched the barbed wire of the compound wall at the airport. All three passengers and the captain survived.

On 27 May 2017, Summit Air Flight 409 was performing a freight flight on a Let L-410 from Kathmandu to Lukla (Nepal) with three crew, was on final approach to Lukla's runway 06 at about 14:04L (08:19Z) with poor visibility when the aircraft lost altitude and touched a tree short of the runway before contacting ground about 3 meters/10 feet below the runway level.

The aircraft slid down the slope before coming to a rest about 200 meters below the runway level. The captain was killed and the first officer, Shrijan Manandhar, died in hospital almost eight hours later.

The third crew member received injuries and was evacuated to Kathmandu the following day after the weather had cleared.

On 14 April 2019, at 9:10 am a Summit Air Let L-410 Turbolet aircraft, registration 9N-AMH, with no passengers on board veered right and left the runway on take off from Lukla Airport and struck a Manang Air Eurocopter AS 350B3e helicopter registration 9N-ALC on the helipad 30 to 50 metres from the runway destroying the plane and the helicopter.

A second helicopter, Shree Airlines Eurocopter AS 350, 9N-ALK, on the helipad sustained little or no damage. The three reported fatalities were the co-pilot of the plane and a police officer on airport security duty who died in the crash and a second police officer who was critically injured and airlifted to Kathmandu where he died in hospital.

The four reported injured include the pilot of the plane and a Manang Air helicopter pilot who were injured and flown to a hospital in Kathmandu where they were reported to be out of danger.

Tenzing–Hillary Airport in eastern Nepal, also known as Lukla Airport, is notorious for being the world’s most dangerous airport. Despite this, the airport is popular due to it’s proximity to Katmandu, where most climbers begin their ascent up Mount Everest.

The aircrafts involved belonged to private companies that transport locals, climbers and tourists to the remote Everest region.

The short runway (527m) has a 600m drop at the end of it. The airport’s altitude stands at 2,845m, giving pilots little time for descent before landing. The runway is surrounded by mountains, making takeoff and landing very tricky.

Unpredictable weather, no navigation aids and no night operations all contribute to the danger of this airport. Watch to see an airplane landing at the infamous airport here.

More than 300 people have died attempting to reach the summit of Mount Everest, with countless more injured.

Yet the dangers begin well before trekkers even reach base camp. The most common way hikers reach the area is to fly to the tiny Himalayan settlement of Lukla, 9,383 feet above sea level.

The alternatives all involve several days trekking, and so multiple flights carry hikers between Kathmandu and Lukla every day. Although the flight time is just 25-30 minutes, the two airports are as different as night and day.

Airports can be challenging to pilots for many reasons, as seen on this list of dangerous airports in Europe. Sometimes it's the short runway as on many Greek islands.

Places like Gibraltar suffer from regular wind shear, while mountainous terrain surrounding airports like Innsbruck creates obvious risks. Airports at high-altitude present dangers due to the effect that low air pressure has on the handling of an airplane.

Tenzin-Hillary Airport in Lukla, Nepal, has not just one, but all of these dangers.

While far from being the world's highest civilian airport—that honor goes to Daocheng Yading Airport in China's Sichuan province—Lukla's altitude is still more than enough to cause pilots problems.

The airport is surrounded on all sides by steep, mountainous terrain. The short runway is perched on little more than a mountain shelf. At one end there's a wall and at the other a steep drop into the valley below.

At these altitudes, air density is considerably lower than at sea level and that has a detrimental impact on the amount of power generated by the aircraft engines, reducing lift.

Reduced air resistance also makes it more challenging to slow the plane down. At high altitudes, the longer the runway, the better.

Unfortunately for pilots landing at Lukla, the airport runway is extremely short at just 1,729 feet long. Runways at many of the world's international airports are more than 10,000 feet long.

So short is Lukla's runway that it slopes uphill with a gradient of almost 12% to assist planes in slowing down in time.

To make matters worse, there is so little opportunity for a missed approach because of the surrounding mountains that there are no go-around procedures.

Once an aircraft starts its approach, it must touch down. Given these factors, only helicopters and small fixed-wing propellor planes are permitted to land.

Weather in the Himalayas is highly unpredictable. Sudden mist, fog, rainstorms or snow are always possible. Despite the short distance and short flight-time, the weather in Lukla can often be completely different from Kathmandu, and frequently changes while the airplane is on its way.

In such circumstances, planes turn around and return to Kathmandu. Afternoons are so frequently cloudy that most flights are scheduled for the early morning. Cancellations from Lukla are common.

Some airports considered challenging or even dangerous by pilots have an exemplary safety record. That's not the case at Lukla, where there has been a list of incidents into double figures. Many of the more recent ones have even been caught on camera.

The most notable occurred in 2008 when Yeti Airlines Flight 103 crashed into the mountain a few feet below the start of the runway. The pilot lost visual contact in heavy fog during final approach but attempted a visual landing nevertheless.

All 16 passengers and two of the three crew were killed. The pilot was the only survivor.

The Civil Aviation Authority of Nepal now sets high standards for pilots. To land at Lukla, pilots must have completed 100 short-takeoff-and-landing flights, have at least one year of such experience in Nepal and have successfully completed ten flights into Lukla with a certified instructor.

There is a technical study underway to assess the feasibility of a runway extension, although this would be limited to just 100 feet. Construction of a new helipad is also underway to increase passenger capacity.


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