Why do planes crash? Here are the five most common causes

Investigators in the wreckage of a crashed plane in Alabama in 2013. Image: Getty.

News of any terrible air accident instantly raises questions about aircraft safety and the threat of terrorism. Until the facts are known, however, it is unwise to speculate on what might actually have caused a specific crash.

What we do know is that there are several causes that are more likely to occur than any other. Here are five. 

1. Pilot error

As aircraft have become more reliable, the proportion of crashes caused by pilot error has increased and now stands at around 50 per cent.

Aircraft are complex machines that require a lot of management. Because pilots actively engage with the aircraft at every stage of a flight, there are numerous opportunities for this to go wrong, from failing to programme the vital flight-management computer (FMC) correctly to miscalculating the required fuel uplift.

While such errors are regrettable, it is important to remember that the pilot is also the last line of defence when things go catastrophically wrong. In January 2009 an Airbus A320 hit a flock of geese over New York City. With no power, the captain, Chesley Sullenberger, had to weigh up a number of options and act quickly. Using his extensive flying experience and knowledge of the plane’s handling qualities, he elected to ditch the aircraft in the Hudson River.

The 150 passengers were not saved by computers or any other automated system. They were saved by the two pilots – the very components that techno-enthusiasts claim can be replaced by computers and ground controllers.

2. Mechanical failure

Equipment failures still account for around 20 per cent of aircraft losses, despite improvements in design and manufacturing quality. While engines are significantly more reliable today than they were half a century ago, they still occasionally suffer catastrophic failures.

In 1989, a disintegrating fan blade caused the number one (left-hand) engine of a Belfast-bound British Midland Boeing 737-400 to lose power. Hard-to-read instrumentation contributed to the pilots’ misreading of which engine was losing power. Confused, the pilots shut off the number two (right-hand) engine. With no power, the aircraft crashed short of East Midlands Airport’s Runway 27, killing 47 and injuring many, including the captain and first officer.

More recently, a Qantas A380 carrying 459 passengers and crew suffered an uncontained engine failure over Batam Island, Indonesia. Thanks to the skill of the pilots, the stricken aircraft landed safely.

Sometimes, new technologies introduce new types of failure. In the 1950s, for example, the introduction of high-flying, pressurised jet aircraft introduced an entirely new hazard – metal fatigue brought on by the hull’s pressurisation cycle. Several high-profile disasters caused by this problem led to the withdrawal of the de Havilland Comet aircraft model, pending design changes.

Southwest Airlines Flight 1248. Image: Gabriel Widyna/airliners.net.

3. Weather

Bad weather accounts for around 10 per cent of aircraft losses. Despite a plethora of electronic aids like gyroscopic compasses, satellite navigation and weather data uplinks, aircraft still founder in storms, snow and fog. In December 2005, Southwest Airlines Flight 1248, flying from Baltimore-Washington International Airport to Chicago Midway International Airport, attempted to land in a snowstorm. It skidded off the runway and crashed into a line of cars, killing a toddler.

One of the most notorious bad-weather incidents occurred in February 1958 when a British European Airways twin-engined passenger aircraft crashed while attempting to take off from Munich-Riem Airport. Many of the 23 killed on the aircraft played for Manchester United Football Club. Investigators established that the aircraft had been slowed to such a degree by slush (known to pilots as “runway contamination”), that it failed to achieve take-off speed. Surprisingly, perhaps, lightning is not the threat that many passengers believe (or fear) it to be.


4. Sabotage

About 10 per cent of aircraft losses are caused by sabotage. As with lightning strikes, the risk posed by sabotage is much less than many people seem to believe.

Nevertheless, there have been numerous spectacular and shocking attacks by saboteurs. The September 1970 hijacking of three passenger jet aircraft to Dawsons Field in Jordan was a watershed moment in aviation history that prompted a review of security. Hijacked by devotees of the Popular Front for the Liberation of Palestine, the three aircraft were blown up in full view of the world’s press.

Despite improvements, malcontents still penetrate the security veil, as with the 2001 “shoe-bomber”, Richard Reid. Fortunately, Reid’s attempt to bring down an aircraft mid-flight proved unsuccessful.

5. Other forms of human error

The remaining losses are attributed to other types of human error, like mistakes made by air traffic controllers, dispatchers, loaders, fuellers or maintenance engineers. Sometimes required to work long shifts, maintenance engineers can make potentially catastrophic mistakes.

In 1990, a windscreen blowout on a British Airways flight nearly cost the life of the aircraft’s captain. According to the Air Accidents Investigation Branch, almost all of the windscreen’s 90 securing bolts “were of smaller than specified diameter”. Rather than attributing the mis-match between bolts and countersunk holes to his selection of the wrong-sized bolts, the maintenance engineer responsible for fitting the new windscreen blamed oversized countersinks. The engineer had not been sleeping well and did the windscreen replacement work during the period when his body clock wanted him to sleep – a time when reasoning and judgement easily falter.The Conversation

Simon Ashley Bennett is director of the Civil Safety & Security Unit (CSSU) at the University of Leicester.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

In South Africa's cities, evictions are happening despite a national ban

An aerial view shows a destroyed house in Lawley, south of Johannesburg, on April 20, 2020. The city has been demolishing informal structures on vacant land despite a moratorium on evictions. (Marco Longari/AFP via Getty Images)

On the morning of 15 July, a South African High Court judge ruled that the city of Cape Town’s Anti-Land Invasion Unit had illegally evicted a man when it destroyed the shack where he was living.

That afternoon, the Anti-Land Invasion Unit was out again, removing shacks in another informal settlement.

Evictions were banned in South Africa for nine weeks, after the national government placed the country under a strict Covid-19 lockdown in late March. At present, eviction orders are automatically suspended until the country moves to a lower “alert level” and can only be carried out with a special order from a judge.

Yet major cities including Cape Town, Johannesburg and eThekwini (created through the merger of Durban with several surrounding communities), have continued to use municipal law enforcement agencies and private security companies to remove people from informal housing. In many cases those operations have been conducted without a court order – something required under regular South African law.

Around 900 people were evicted from three informal settlements in eThekwini during the eviction ban, according to the Church Land Programme, a local NGO. Its director, Graham Philpott, says it’s also aware of evictions in other informal settlements.

While evictions aren’t a “new experience” in these communities, the NGO released a report on lockdown evictions because they were “so explicitly illegal”. “There was a moratorium in place,” Philpott says, “and the local municipality acted quite flagrantly against it. There’s no confusion, there’s no doubt whatsoever, it is illegal. But it is part of a trend where the eThekwini municipality has acted illegally in evicting the poor from informal settlements.”

Evictions also took place in Cape Town and Johannesburg during so-called “hard lockdown” according to local activists. In eThekwini and other municipalities, the evictions have continued despite restrictions. In Cape Town, authorities pulled a naked man, Bulelani Qholani, from his shack. That incident, which was captured on video, drew condemnation from the national government and four members of the Anti-Land Invasion unit were suspended. 


The cities say they’re fighting “land invasions” – illegal occupations without permission from the land owner.

“Land invasions derail housing and service projects, lead to the pollution of waterways, severely prejudice deserving housing beneficiaries and cause property owners to lose their investments over night,” Cape Town’s executive mayor, Dan Plato said in a statement. (Plato has also claimed that Qholani did not live in the shack he was pulled from and that he disrobed when municipal authorities arrived.)

South African municipalities often claim that the shacks they destroy are unoccupied. 

If they were occupied, says Msawakhe Mayisela, a spokesman for the eThekwini municipality, the city would get a court order before conducting an eviction. “Everything we’re doing is within the ambit of the law,” Mayisela says. But “rogue elements” are taking advantage of Covid-19, he added.

“We fully understand that people are desperately in need of land, but the number of people that are flocking to the cities is too much, the city won’t be able to provide housing or accommodation for everyone overnight,” he says. 

While eThekwini claims to be a caring city, local activists say the evictions show otherwise.

In one case, 29 women were evicted from shacks during the hard lockdown. With nowhere to go, they slept in an open field and were arrested by the South African Police Service for violating the lockdown, Philpott says.

“These evictions are dehumanizing people whose dignity is already compromised in many ways,” says S’bu Zikode, the president of Abahlali baseMjondolo, a community organization whose Zulu name translates to “the people of the shacks”. 

“It has reminded us that we are the people that do not count in our society.”

Municipal law enforcement and private security contractors hired by cities regularly fire rubber bullets, or even live ammunition, at residents during evictions. Some 18 Abahlali baseMjondolo activists have been killed since the organization was founded in 2005, Zikode says, most by the eThekwini Land Invasion Unit and Metro Police.

(Mayisela says that if city employees have broken the law, Abahlali baseMjondolo can file a complaint with the police. “There is no conclusive evidence to the effect that our members have killed them,”  he says.)

Other Abahlali baseMjondolo activists have been killed by what Zikode calls “izinkabi,” hitmen hired by politicians. Two eThekwini city councillors were sentenced to life in prison 2016 after they organized the killing of Thuli Ndlovu, an Abahlali baseMjondolo organizer. A member of the Land Invasion Unit who is currently facing a charge of attempted murder after severely injuring a person during an eviction remains on the job, Zikode says.

South Africa’s 1996 constitution is intended to protect the public from arbitrary state violence and guarantees a right to housing, as well as due process in evictions. But for Zikode, the South African constitution is a “beautiful document on a shelf”.

“For the working class and the poor, it’s still difficult to have access to court. You’ve got to have money to get to court,” he says. 

The actions by municipal law enforcement are breaking down social trust, says Buhle Booi, a member of the Khayelitsha Community Action Network, a community group in the largest township in Cape Town.

“There’s a lack of police resources and those very few police resources that they have, they use to destroy people’s homes, to destroy people’s peace, rather than fighting crime, real criminal elements that we see in our society,” Booi says.

For him, it’s a continuation of the practices of the colonial and apartheid governments, pushing poor people, most of whom are Black, to the periphery of cities.

Around one-fifth of South Africa’s urban population live in shacks or informal dwellings, according to a 2018 report by SERI. Many more live in substandard housing. City governments maintain that the shacks destroyed during anti-land invasion operations are unfinished and unoccupied. But Edward Molopi, a research and advocacy officer at SERI, says that this claim is an attempt to escape their legal obligations to get a court order and to find alternative accommodation for affected people. 

The roots of the current eviction crisis go back to apartheid, which barred non-white people from living in cities. Between the 1940s and 1970s, tens of thousands of people were forcibly relocated from neighbourhoods like Johannesburg’s Sophiatown and Cape Town’s District Six to remote townships.

In the 26 years following the end of apartheid, deepening economic inequality and rampant unemployment have limited access to formal housing for millions of South Africans. Government housing programs have mostly focused on building small stand-alone homes, often on the peripheries of cities far from jobs and amenities.

While these well-intentioned projects have built millions of homes, they’ve failed to keep up with demand, says Marie Huchzermeyer, a professor at the Centre for Urbanism & Built Environment Studies at the University of the Witwatersrand in Johannesburg. Government-funded housing projects “will never on it’s own be enough,” she says. “It has to be accompanied by land release.”

Government policies call for the “upgrading” of informal settlements and the formalization of residents’ occupation. But “there are still very, very, very few projects” of that nature in South Africa, Huchzermeyer says. “Even if it’s an informal settlement that’s been around for 20 years, there still seems to be a political wish to punish people for having done that.” The government wants people to go through the formal process of being given a house, she says – and for them to be thankful to the government for providing it.

At the municipal level, change will require “real leadership around informal settlement upgrading and around ensuring that land is available for people to occupy,” she says. 

Despite the end of enforced racial segregation, spacial apartheid remains a factor in South Africa. There are few mixed-income neighbourhoods. Those who can afford to often live behind walls in sprawling low-density suburbs, while the poor live in overcrowded slums and apartment buildings.

The creation of the apartheid city “didn't happen by chance,” says Amira Osman, a professor of architecture at the Tshwane University of Technology. “It was a deliberate, structured approach to the design of the city. We need a deliberate, structured approach that will undo that.”

Since last fall, Johannesburg’s Inclusionary Housing Policy has required developments of 20 or more units to set aside 30% of those units for low-income housing.

The policy, which faced significant opposition from private developers, won’t lead to dramatic change, says Sarah Charlton, a professor at the Centre for Urbanism and Built Environment Studies, but it is “an important and significant step.”

Zikode isn’t optimistic that change will come for shack dwellers, however.

“People in the high positions of authority pretend that everything is normal,” he says. “They pretend that everyone is treated justly, they pretend that everyone has homes with running water, that everyone has a piece of land – and hide the truth and the lies of our democracy.”

Jacob Serebrin is a freelance journalist currently based in Johannesburg. Follow him on Twitter.