With another recent passenger problem on Turkish, a divert to Stansted was used. I'm guessing LY was confident in their own security staff at LHR this time.
Tel Aviv-bound flight diverted to London over ‘disruptive’ passenger
Witness says woman ‘was choking random passengers’; traveler taken into custody at Heathrow; Air Canada flight resumes journey to Israel
By Times of Israel staff February 15, 2017, 11:30 am
An Air Canada passenger flight from Toronto to Tel Aviv made an emergency landing at London’s Heathrow Airport early Wednesday morning following a “disturbance” from a passenger on board.
Flight 84 had been scheduled to land in Tel Aviv at 10:15 a.m., but was forced to declare an emergency six hours into the flight and landed in London shortly thereafter, according to eTurboNews, a global travel industry news site.
The plane’s pilots alerted air safety authorities that they would not continue the flight while the disruptive passenger remained on board.
A witness told Ynet that a disorderly woman was choking travelers at random, leading passengers to physically restrain her until the plane touched down at Heathrow.
Ten police cars awaited the aircraft on the tarmac, and officers boarded the plane upon landing to remove the woman.
The plane continued on its way to Tel Aviv once the passenger had disembarked. It was slated to land in Tel Aviv shortly after 1 p.m.
The incident came days after Air Canada announced that it was introducing bi-weekly direct flights from Tel Aviv to Montreal from June through the conclusion of the Jewish High Holiday season in October.
Tel Aviv-bound flight diverted to London over 'disruptive' passenger | The Times of Israel