A man on a British Airways flight had to go to hospital after being bitten as he stepped in to help crew members subdue a "violent passenger".
Christopher McNerlin was flying back to Heathrow from Dubai on Friday when he went to the aid of a stewardess dealing with an aggressive fellow traveller.
He was bitten on the arm during the incident and had to go to hospital for a check-up - but was allowed to sit in the cockpit by the pilot as thanks for his efforts.
Mr McNerlin, who works for "trend forecasting" company WGSN, posted pictures to social media of the bite mark, along with one of himself giving the "thumbs up" as he sat in the cockpit once the plane had landed safely and was in a hangar.
He wrote: "That time when you help restrain and handcuff a nutter at 40,000ft. He bites you, but it's all OK because Captain Kendal lets you sit in the cockpit."
And he added: "At A&E after helping the British Airways stewardesses restrain a violent passenger on board yesterday's BA0104."
"Incredible team on the flight, especially Hayley, who put herself in harm's way to protect passengers.
"Thanks to British Airways Captain Kendal for showing me the cockpit. The bite and A&E were almost worth it."
British Airways thanked Mr McNerlin, from Stratford-upon-Avon, saying: "We hope you are all right. I'm sure Hayley would've appreciated your assistance on board. Thanks."
@Chris_McNerlin for our incident records. I'm sure Hayley would've appreciated your assistance on board. Thanks. ^Claire— British Airways (@British_Airways) April 2, 2016
The airline said the matter was now being dealt with by police, who said officers were called to the airport shortly before 6pm.
A Metropolitan Police spokeswoman said: "Officers attended and found a 21-year-old man who had assaulted a passenger.
The man was arrested on suspicion of actual bodily harm and being drunk on board an aircraft.
"He was taken to a west London police station and has been bailed to a date in late May.
"The injured passenger received medical assistance for a minor injury at the scene."