A pilot for Dubai-based airline Emirates was jailed for four months by a British court Friday after he tried to board his plane while seven times over the legal alcohol limit. Concerned security staff at London’s main Heathrow airport alerted police after Captain John Cronly-Dillon repeatedly stumbled at check-in, ate a whole packet of chewing gum and swallowed copious amounts of water. The 51-year-old Australian had been within minutes of piloting a jet from the British capital to Dubai when he was arrested on September 13 this year, Isleworth Crown Court in west London was told. Judge Usha Karu told Cronly-Dillon she had no alternative but to end his unblemished 25-year career in the skies with an immediate prison sentence because of the seriousness of the offence. ‘‘I am told you followed the 12-hour alcohol rule (banning drinking before a flight). But it seems to me you must have realised you were still under the influence of alcohol and yet you decided to take the risk and board the plane. ‘‘The fact is had you not been stopped... and discovered, you would have put the lives of a number of passengers at risk.’’ Prosecutor Douglas Adams told the court that Cronly-Dillon was breath-tested after police were first alerted and found to have 134 micrograms of alcohol in 100 millilitres of blood. The limit was 20 micrograms, he said. Cronly-Dillon, who gave an address in north London, admitted one charge of ‘‘performing an activity ancillary to an aviation function’’ while over the drink-fly limit. His lawyer said her client, who was instantly dismissed by bosses, was ‘‘extremely remorseful’’ at what happened. Emirates said in a statement they had a zero-tolerance approach to breaches of alcohol-related regulations and it was the first time they had had to deal with such an incident in 21 years.