Early in the morning of July 5, 2014, videographer Miguel Ángel captured a near catastrophic collision of two airplanes at Barcelona's El Prat International Airport. The incident involved a UTair Boeing 767-300 flying in from Moscow and an Aerolíneas Argentinas Airbus A340-300 taxiing down the runway in preparation for takeoff.
The Utair 767 was just about to land on runway number two when the Russian pilot saw the Argentinas Airbus and quickly pulled up to avoid it. It's evident from the video how close this was to becoming a major disaster. Via Twisted Sifter.
And why/how did UTair 767 retract his landing gear so fast?
As the 767 approaches and starts to pull up, it has about 40 degrees of flaps and the gear is down and locked. As it passes overhead, flaps are still deployed, but the bottom is clean--gear fully retracted and doors closed. Time elapsed could not be more than a second or two.
While it's not clear why the Aerolineas pilot did not stop at the hold-short before the runway, this is a simple go-around, and happens on occasion. It is entirely possible the Aerolineas plane would have cleared the active before the UTair plane passed through, but pilots know to abort the landing in such circumstances - had the Aerolineas plane halted mid-runway there would be no way to avoid it once a certain amount of airspeed had been shed.
http://www.bbc.com/news/world-europe-28200666