A British Airways pilot used a cockpit computer to allegedly type "Show Us Ur T**s" before taking a picture of the message and texting it to his lover.
The Sun reports that during the safety breach, Graeme Hindley also took a photo out of the window of the plane as it descended over central London and sent it to the single mum.
Hindley, who has worked for BA for 20 years, said that he was "not distractable" and a "total pro" when she told him to concentrate on flying the plane.
The woman has now split from the pilot and told The Sun: "It's terrible Graeme should be sending messages on his phone and mucking about when he has got passengers on board relying on him, and expecting him to get them somewhere safely.
"I thought I had a responsibility to the public to make them aware of Graeme's apparent negligence.
The pilot, 43, and the mum-of-three reportedly met twice for sex after meeting on a ferry.
She claims he sent the pictures as the flight departed from Heathrow to Hanover in April.
According to the Daily Mail, Hindley mainly flies Airbus A319 and A320 planes on short-haul routes around Europe.
"We take any breaches of these standards very seriously and we will be investigating this matter very thoroughly and take appropriate action."
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