The deadly helicopter crash on Saturday night that took the lives of Leicester City football club owner Vichai Srivaddhanaprabha and four others on board has raised fresh concerns over the safety of helicopter flights.
Mr Srivaddhanaprabha’s helicopter, an AgustaWestland AW-169, was bound for Luton airport, from where he was scheduled to return to his native Thailand. Witnesses have said the "engine stopped" in the air, before the helicopter plunged to the ground at around 8.45pm.
It was claimed on Sunday night that the pilot averted a greater disaster by directing the in-trouble helicopter towards the south-east corner of the King Power stadium and away from supporters in the car parks leaving after Leicester's 1-1 draw with West Ham United.
It took more than 20 minutes for the flames to be extinguished before emergency services were able to survey the wreckage. Sources at Leicester have said there were no more casualties on the ground.
Have there been other similar accidents?
This year has seen a string of helicopter accidents around the world, including this month in New Zealand when a helicopter burst into flames after crashing in farmland just north of Wanaka Airport on South Island, killing the pilot and two passengers on board. The tragedy followed the death of the pilot’s older brother three months earlier, also in a helicopter crash near Stevensons Island in Lake Wanaka.
Last month in Alaska, a helicopter travelling from Juneau to Yakutat went into free fall before crashing onto a beach in Glacier Bay National Park. The cause of the fatal accident, which killed both pilots and a passenger, has yet to be determined, according to the US National Transportation Safety Board (NTSB).
Earlier this year in March, a helicopter crashed into the East River killing all five passengers on board the Eurocopter AS350. The group had chartered the flight from Liberty Helicopters for a photoshoot of the Manhattan skyline. The pilot was the only survivor of the crash.
The incident was the third crash in 11 years involving Liberty Helicopters, which has been operating for more than 30 years. One of the incidents left nine people dead, including the pilot, after the helicopter (a similar make to the one involved in this week’s accident) collided with another plane over the Hudson River.
Issues around the pilots being unable to see and avoid each other in the moments before the collision were deemed to be the cause of the crash, according to the NTSB.
Earlier this month, New York senator Charles Schumer warned tourists from taking helicopter trips over the East River, after the company involved in the March crash came under fire for offering discounted flights on the same service currently under investigation by the US government.
"The FAA [Federal Aviation Administration] is not allowed to shut them down until the investigation has concluded and the other thing we will look to do is change the law," Senator Schumer said at a press conference.
"If there's serious investigation involving safety and people died, the FAA should have the temporary power to shut them down, but until they do, we're asking them to stop flying and we're warning consumers, tourists, avoid this."
But are helicopter crashes are becoming rarer?
According to the latest statistics from the International Helicopter Safety Team (IHST), the number of helicopter accidents in Europe dropped from 103 in 2013 to 43 in 2017, more than half. The number of fatal accidents has dropped from 25 to 11 in the same period.
The European Helicopter Safety Team (EHST), too, says that 311 accidents were reported in Europe between 2000 and 2005; this fell to 162 between 2006 and 2010.
Of the 49 countries surveyed between 2013 and 2017, “total civil helicopter accidents in 2017 were down six per cent compared to the prior year and fatal accidents were reduced by 17 percent year-over-year,” while “comparing 2017 to 2013, total accidents decreased by 32 per cent and fatal accidents were cut by 44 per cent,” the IHST report said.
The FAA said: "Prior to 2006, the number of worldwide civil helicopter accidents was rising at a rate of 2.5 per cent per year. Since 2006, the worldwide civil helicopter fleet has grown by 30 per cent but the number of accidents has decreased in key global regions by 30 to 50 per cent."
How common are helicopter crashes?
For a relatively niche mode of transport - the Civil Aviation Authority (CAA) says there are just 1,283 helicopters of all types registered in the UK - crashes seem to occur fairly frequently.
"I don’t think that there are reliable statistics on helicopter crash rates either expressed as per hour flown or per distance travelled," said Dr Rob Hunter, head of flight safety at the British Airline Pilots' Association (Balpa). "It is also important to compare like with like, commercial airliners have fantastic safety – seeing around one fatal accident per 10,000,000 hours. But these aircraft cannot fly in the types of roles that helicopters do."
"In offshore helicopter operations in support of the oil and gas industry, the fatal accident rate is around one per 250,000 hours."
One might argue that helicopter crashes stand out in our consciousness as they are often in and around popular tourist destinations.
Earlier this year, a helicopter crash in the west rim of the Grand Canyon saw three Britons killed. Papillon Grand Canyon Helicopters, the firm which operated the sightseeing flight, receives around 600,000 passengers a year for trips around the US national park.
This was not the first fatal helicopter crash involving a Grand Canyon tour operator. One of the deadliest in the area occurred in 1986 when 25 were killed following a collision between a twin-engine sightseeing plane and a helicopter at Scorpion Creek near Crystal Rapids at the south rim of the canyon.
The crash took place at the start of the peak tourist season in June and sparked a fierce debate over the safety of flights over the US national park.
Furthermore, the latest incident at the Grand Canyon wasn't the first to involve Papillon. In August 2001, another of its helicopter tours ended in tragedy when it crashed near Meadview, Arizona, killing the pilot and five passengers. The pilot's decision to descend too fast and too close to the scenic Grand Wash Cliffs was blamed for the incident, according to a NTSB report.
Are helicopters more dangerous than planes?
On the face of it, yes. The FAA says the fatal accident rate across all aviation types in the US is 0.84 per 100,000 flight hours, less than the 1.02 it reports for helicopters. But the fact that helicopters are used in risky operations, such as search and rescue missions, in war zones, and sometimes in bad weather, skews this figure.
“Helicopters already face a series of extra difficulties due to their typical operations in challenging areas or situations, and the fact that they are particularly vulnerable to threats such as drones or lasers," Dr Hunter told Telegraph Travel.
"Helicopters operating at low level are extremely vulnerable to collisions with drones. If the drone strikes the helicopter main or tail rotor this could be catastrophic. Also many helicopter windscreens are nowhere near as strong as airliner windscreens and so if the drone hits the windscreen it could enter the cockpit and kill or injure the pilots. Safety measures against drone strikes are, at this time, seriously deficient. More needs to be done to prohibit them sharing the same airspace as manned helicopters," he adds.
"In North Sea operations there is so much noise in the cockpit that pilots are having to turn up their headset volumes so that they can hear each other and air traffic above all the noise. This is leading to concerns about helicopter noise exposures. We need up-to-date noise assessments to ensure the health and safety noise regulations are being complied with.
"If a helicopter has to do an emergency landing on water it will likely turn over – this means that pilots have to wear immersion suits, life jackets, a helmet and a carry short-term underwater breathing bottle clipped to their suit, all this equipment is so bulky that many helicopter pilots develop serious orthopaedic problems."
What should I look for when booking a helicopter tour?
"Beyond checking that the company concerned has the necessary local licences and permits, and is well reviewed on social media, it’s simply not feasible for a tourist to judge whether or not a particular adventure excursion - whether it is a helicopter flight, white water rafting or a pony trek - is going to be well-run and safe," explains Nick Trend, Telegraph Travel's consumer expert.
"But you will have better legal protection if you book it as part of a package holiday with a UK-based tour operator. It will then be liable for your safety, and should ensure that the local company it has booked you with is properly licensed and professionally operated. If there are problems or an accident, then you will also - if necessary - be able to follow up in the UK courts."