Written for E&T
With only one in 1.2 million flights ending in an accident and with the estimated chances of dying in a plane crash one in 11 million, aviation is still statistically the safest form of transportation. However, with high-profile catastrophic accidents in which there are no survivors dominating newspaper headlines over the past year, the risk-conscious public can be forgiven for thinking, “Does the technology not exist to mitigate such a grim outcome of an aviation disaster?” E&T investigates.
“When man has landed on the Moon, we cannot underestimate the technology at hand today to do almost miracles,” Kumar Mysore, an airworthiness expert from the Royal Aeronautical Society, told E&T in an exclusive interview for this article. “Of course, if we discount the costs. It’s more about will than capabilities.”
We looked at five key technological solutions to introduce greater safety on board today’s aeroplanes. Some of those potentially life-saving approaches may seem rather simplistic, such as turning seats around to have them facing backwards. Others will require major advancement in research, such as the parachutes for commercial jet-liners. The good news, at least, is that the options are many and even though cost-aware airlines may not be eager to embrace them, there are researchers out there who want to make aviation even safer than it already is.
There may have been little that could have saved passengers aboard the ill-fated Germanwings flight 4U9525 after derailed co-pilot Andreas Lubitz decided to smash the Airbus A320 into a mountain rock in the French Alps, having earlier locked his captain out of the cockpit. Hitting the cliff at 700km/h, the plane disintegrated into a shapeless pile of rubble with not a single fragment of the nearly 40m long craft larger than a passenger car.
In the eight minutes of terror, for which the deceived captain was desperately trying to force his way back into the flight deck, air-traffic controllers on the ground were equally desperately trying to contact the inexplicably descending airplane offering to free any nearby airport for an emergency landing.
But what if they could have done more? What if they could have taken control over the plane regardless of Lubitz’s actions or intentions and steer it safely to its destination? In fact technology to do exactly that already exists, at least as a working concept.
In 2006, Boeing patented an ‘uninterruptable autopilot system’ that allows actions in the cockpit to be overridden by commands beamed up via a radio or satellite link. Developed presumably in reaction to the 9/11 hijacking attacks, the system would allow government agencies or operators in specific circumstances to take over control of any aircraft and steer it to safety from the ground.
According to reports published at the time when the patent was awarded, the system has its own power supply independent on the rest of the aircraft and would keep the plane in automatic mode until after landing when mechanics and government security agents would be called to switch off the system.
Germanwings 4U9525 is not the first aircraft in the recent history that could have been saved with a remote control. One of the more plausible theories behind the disappearance of Malaysia Airlines Flight 370 in March last year speaks about a sudden loss of cabin pressure which rendered the crew and passengers unconscious. The plane then continued flying on an autopilot, following the last parameters inserted by the pilot, until it ran out of fuel several hours later in the middle of the Indian Ocean. The hypothesis mirrors the 2005 crash of Cypriot Helios Airways near Athens, Greece, which saw the unresponsive jetliner flying for about an hour before crashing into a mountain. With the crew incapacitated but the aircraft undamaged, remote control would have provided the only way to save the passengers.
2. Auto Avoid systems
Airbus itself was in the not so distant past developing a system that could have prevented the reportedly depressed first officer Lubitz from intentionally crashing the plane. In 2004, the plane maker together with engineering firm Honeywell tested the so called Auto Avoid technology. Considered for Airbus’s than under development superjumbo A380, the system would automatically steer an aircraft away from solid obstacles including hills and buildings if pilots didn’t respond to audible warnings from ground-collision avoidance systems – the exact same warnings as described by investigators familiar with the contents of the cockpit voice recorder of the tragic Germanwings flight.
According to the Wall Street Journal, the system could also kick in whenever the aircraft entered computer generated no-fly zones around skyscrapers and important buildings or veered considerably off it planned trajectory.
Although a standard piece of safety equipment on most military aircraft and even some smaller executive jets, parachutes for passengers are not carried aboard large commercial planes. The simple and efficient devices may in theory have helped Flight 4U9525 passengers to escape from the ‘hijacked’ plane. However, experts say, in most aviation accidents, including the ill-fated Germanwings flights, there wouldn’t be enough time for all passengers to jump to safety.
There is an alternative though – airframe parachutes designed to safely lower the whole aircraft to the ground.
In fact, US-based firm BRS Aerospace has been manufacturing what they call ballistic recovery parachute systems for more than 30 years. “It is a parachute canopy deployed by a solid fuel rocket motor that can open, depended on air speed, in less than one second,” the firm’s founder Boris Popov told the E&T. “It’s a very small unobtrusive package that fits into most general aviation and sports aircraft and up until today we have saved 324 lives around the world.”
Having won certification by the US Federal Aviation Agency in 1993, the firm has sold over 29,000 parachutes to manufacturers such as Cirrus, Flight Design or Cessna.
“Statistically one of a hundred parachutes that we have sold gets used,” says Popov, who started the company after miraculously surviving a 150m plummet on a damaged glider.
Even if deployed at a rather low altitude, the parachute can slow down the aircraft to a survivable impact. “We’ve had saves when the parachute opened less than two hundred feet (60m) above the ground,” says Popov.
However, there is a catch. For every ten kilos of aircraft mass, the parachute needs more than 2 square meters of area in order to be effective.
With currently available materials, reasonably-sized parachutes can be provided for planes of up to 300kg – that’s a five-seater or six-seater airplane. Popov said the firm is already developing parachutes for planes carrying up to 12 passengers. To have such a technology on board of a large passenger jet is, however, so far impossible.
“The biggest problem right now is material technology,” Popov explains. “We need to make a parachute that is going to be small enough and light enough. That won’t take away a significant portion of the useful load of the aircraft. We could theoretically provide a parachute today but it wouldn’t be able to carry more than a few passengers on a Boeing 757.”
An Airbus A320, such as the one that crashed in the Alps, would need about six parachutes each about the size of a football field.
Popov is optimistic that with advances in nanotechnology and material research, a fabric would eventually be created so thin and lightweight but exceptionally sturdy to allow manufacturing of such parachutes.
“I believe that in five to ten years we may have materials that would allow us to start seriously considering parachutes for larger planes.”
The recent string of tragic aviation accidents may help swing the momentum in favour of such backup safety features. Popov envisions the technology could eventually move from current manually triggered devices to smart parachutes that would be able to autonomously react to dangerous deviations in the aircraft’s behaviour.
4. Bomb-proof ‘Fly Bag’
The 1988 Lockerbie disaster may seem like ancient history, however, experts admit that the danger of someone smuggling an explosive device on board an aircraft either inside checked-in luggage or directly into the cabin is, despite all modern security measures, nowhere near zero.
On the Christmas Day of 2009, an Al-Queda related terrorist managed to get on board of a flight from Amsterdam to Detroit with a plastic-based bomb sewn into his underwear. Fortunately, the plot failed as the perpetrator didn’t manage to detonate the bomb properly. A year later, remotely controlled bombs concealed in printer cartridges were discovered among cargo of two planes en route from Yemen to the USA.
An Italian-led research project called Fly Bag is now developing technology that could allow planes in the future to survive a Lockberbie-sized explosion. Made of highly resistant fabric, the simply looking Fly Bag comes in two variants – for cabin use and cargo holds.
“The idea is to protect the aircraft using a bag, a system made of textile that could be folded inside a headlocker under normal circumstances and if a suspicious device is found, it would be placed inside the fly bag and placed to the least risk bomb location – a reinforced part of the aircraft where an explosion would cause minimal damage,” Alessandro Bozzolo, co-ordinator of the project funded through the EU’s 7th framework research programme told E&T.
While the cabin-version requires the crew to act before the explosion, the cargo hold type of the Fly Bag – coming in two versions for narrow-body and wide body aircraft, provides a ready passive preventive countermeasure against a Lockerbie-inspired plot.
In case of the tragic 1988 flight from Frankfurt to New York, almost 260 people died after the plane had been rendered unflyable due to the damage caused by a terrorist-planted bomb inside the cargo hold.
“In the cargo hold, the luggage is already placed inside a system that protects against blast,” Bozzolo explains. “In the case of wide-body aircraft, our system made of multi-layered textile is fitted inside the standard aluminium containers that are used for loading luggage. The second type is suitable for narrow-body aircraft where usually the aluminium containers are not used. So the idea is to create a bag that is installed inside the cargo hold of the narrow body aircraft and like an internal screen protects the fuselage against the blast.”
Last year, the team successfully tested the technology inside a Beoing 747 during a ground-based experiment. Further test are planned for this summer.
A simple, yet efficient solution – having passengers seated facing backwards would improve survivability of crashes involving abrupt deceleration. In fact, military planes are being equipped with backward-facing seats for decades. According to flight surgeons, human body can absorb much more stress through the back than through the chest and abdomen.
“In the crash of a forward seat, the forward force is taken by the seat belt in a limited area of restraint around the body,” explains the Royal Aeronautical Society’s Kumar Mysore. “This force is better distributed on the person resting on the backrest of aft facing seat.”
According to research, a centre of gravity of a decelerating person in a backward-facing seat would be about 20cm higher than in a forward-facing seat due to the placement of the seatbelt. That means the force of the deceleration would act higher, requiring additional strengthening of the anchoring of the seat to the floor.
“Aft facing seats will require a bit of redesign, including minor strengthening of the seat attachment to the floor,” Mysore confirms. “But I think the reason for not installing backward facing seats is mostly about following the tradition. It’s easy to keep doing what has been done in the past. The chance of dying in an aircraft crash is 1 in 11 million; while a fatal accident is 1 in 5000. The industry is in no haste to change this happy-go-luck state.”
Currently, seats in passenger aircraft have to be able to withstand dynamic forces of 16G. Unlike seats in all moderns cars, they have no airbags and only a two-point seat belt with the passengers instructed to ‘brace’ in case of a harsh landing.
More Sharing ServicesShare | Share on facebookShare on twitterShare on emailShare on print