A plane from Stansted was directed into the path of another aircraft by an over-worked air traffic controller.
An official report found the pilots of the two aircraft had flown too close to each other over Essex, after the Boeing 737 had been told to climb.
An investigation found the air traffic controller had given the instruction to the wrong plane because of his high workload.
The Stansted-based airline Ryanair has cancelled 166 flights today to and from and over France because of another strike by French air traffic controllers.
It's the 52nd French strike since 2009 and Ryanair are calling on the European Commission to take action.
Ryanair says 30,000 customers have had their flights cancelled today and over 100,000 others will suffer severe delays.
It is time for action by the European Commission following this latest French ATC strike aimed at disrupting as many travel plans as possible.
The frequency of these strikes, right in the middle of the holiday season only serves to underline how urgent action is required to help reduce the impact of these strikes.
Stansted-based airline Ryanair has revealed it plans to cut fares by 7% this year as annual profits soared.
The budget airline wants to reduce its prices in a bid to keep passengers flying despite concerns following terror attacks in Paris and Brussels.
The impact of the recent EgyptAir plane crash may further weaken the appetite for international travel over the coming months.
The cuts came as Ryanair posted profits after tax up 43% to £959 million in the year to March compared with a year ago.
The full-year to 2016 was a year in which we delivered significant traffic and profit growth in all four quarters.
The Chancellor George Osborne has been in Essex claiming that leaving the EU would be a one way ticket to a poorer Britain.
He spoke alongside political opponents Labour's Ed Balls and Vince Cable from the Liberal Democrats as the Remain campaign staged an event at Stansted Airport.
They warned that Brexit could mean an end to cheap flights and threaten investment such as the new Ryanair training centre which will create 450 jobs.
The Vote Leave campaign pointed out that the Ryanair boss Michael O'Leary said only a few months ago that Brexit would not cause fares to rise.
The Stansted announcement comes after more than 300 business leaders urged Britain to vote to leave the European Union, warning that the country's competitiveness is being undermined by its membership.
In a letter to The Daily Telegraph, they argued that businesses will be "free to grow faster, expand into new markets and create more jobs" if they are unconstrained by EU rules.
Click below to watch a report by ITV News Anglia's Matthew Hudson
Stansted airport has had its busiest ever winter season, with 8.64 million passengers passing through.
Meanwhile, Luton Airport is celebrating two years of continued passenger growth, with 1 million passengers passing through in March.
Sniffer dogs and extra police will be on patrol at at Stansted Airport this weekend as officers attempt to reassure passengers.Read the full story ›
After the Queen declared the Norman Foster terminal building at Stansted open on 15th March 1991 just over a million people a year were using the Essex airport.
In the years which followed a lot has changed. Stansted is now a major hub for low cost airlines and annual passenger numbers have risen to more than 23 million. The terminal has been extended twice.
To mark the 25-year anniversary, ITV News Anglia produced a special programme live from the busy terminal presented by Jonathan Wills and Becky Jago
In 1991 the Queen opened the new terminal building at Stansted. In the 25 years that have followed the airport has undergone rapid growth.Read the full story ›
Stansted airport in Essex has had its busiest February on record with 1.69 million passengers passing through the terminal.
The number of passengers at London's third airport has been growing month on month for nearly two years. The figure for February was up 15% on 2015.
Nearly 23 million passengers used Stansted in the past year, the highest annual total since 2008.
“This strong demand continues to be driven by record numbers of passengers on each flight arriving and departing from Stansted plus airlines increasing capacity on key routes including Berlin, Cologne, Prague and the Scottish cities of Edinburgh and Glasgow.
“Stansted is the UK’s fastest growing major airport at the heart of the UK’s innovation corridor and we remain focused on providing passengers with even more choice of airlines and destinations to better serve our region’s needs.”
Last month British Airways announced it would start flying from the Essex airport to four popular holiday destinations and has just added a weekly flight to Berlin.
A woman has been arrested and fined after staging an impromptu striptease protest about security delays at Stansted airport in Essex.Read the full story ›