Pilots report more than 1,400 laser incidents in 2015
More than 1,400 incidents of lasers being shone at aircraft were reported to the UK's Civil Aviation Authority (CAA) in 2015.
The number was slightly lower than in 2014 - but reports by police helicopter pilots more than doubled.
The British Airline Pilots Association (Balpa) said the increasing power of lasers raised the possibility of a serious accident.
One pilot called for the sale of strong lasers to be controlled.
The CAA said 1,439 laser incidents had been reported in 2015, a slight decrease on the previous year's total of 1,447.
But the National Police Air Service told the BBC its helicopter pilots had reported 91 laser incidents in 2015, more than double the previous year's total of 35.
Stephen Landells, flight safety specialist at Balpa, called for lasers to be classed as weapons.
"If you shine even the weakest laser at an aircraft, you can dazzle and distress the pilot at a critical stage of flight," he told BBC Radio 5 live.
"We need to educate people. It's not only illegal, you are actually endangering people's lives when you shine a laser at an aircraft.
"We're looking to try and get the law changed to take into account the fact that these lasers can be used as weapons."
Airline pilot Janet Alexander told the BBC: "A concentrated laser beam into the cockpit is analogous to a lightning strike.
"We're not talking about the things you use in lectures... we're talking about the sort of things you might see at an open air music festival or something like that.
"Even if it doesn't hit your retina, it's very dazzling and you do momentarily lose your vision."
A Home Office spokeswoman said: "The UK has strict laws dealing with people who recklessly use lasers against aircraft and endanger the lives of passengers and crew.
"Anybody who does so faces up to five years in prison."
The UK Civil Aviation Authority told BBC Radio 5 live: "We strongly urge anyone who sees a laser being used in the vicinity of an airport to contact the police immediately".