Student pilots who are practising night flying near Feilding and Palmerston North are being targetted with dangerous lasers by members of the public.
Massey University's aviation school is warning people to stop shining lasers into planes at night because it could cause a pilot to crash.
School of Aviation chief executive Ashok Poduval said the lasers could cause temporary blindness.
"When they're flying at night you need to keep eyes adjusted to darkness and not have any bright lights around you, so when suddenly there's a flash of light your night vision is either completely reduced or completely removed."
Poduval said it was difficult to track down who was shining the beams up at the plane but police and the Civil Aviation Authority have been notified.
He said if anyone was caught, they could face charges for interfering with an aircraft.
Flight instructor Shannon Mickleburgh told Stuff pilots could get flash blindness where they could not see anything.
"It's quite disorientating when it does happen.
"The little laser on the ground ends up being quite bright by the time it makes it up to the aircraft.
"You've got a glass canopy so everything just reflects. It's extremely bright when it actually is on the canopy itself at night because you get accustomed to the darkness and all of a sudden you've got a bright light."