LONDON, Ont. - Steps are being taken to resume landings at the air ambulance helipad at the London Health Sciences Centre's (LHSC) University Hospital.

But it's uncertain how much longer the pad will be off limits.

Officials at Ornge air ambulance suspended landings at the location on Sept. 12.

They say the decision was made after an aviation safety concern was raised internally with respect to obstacle clearance along departure routes.

In a news release Wednesday, Ornge says a comprehensive review validated those concerns and that the LHSC has hired an engineering firm to address those concerns.

A hospital spokesperson declined to go into specifics, but cited increased urbanization as a contributing factor.

And Ornge Aviation's chief operating officer, Ian McLean, says the challenge at University Campus is that there are no alternative landing areas in the event of a malfunction on take-off.

"You have to take contingency into account when you're thinking about helipad operations. And by contingency operations I'm talking about our aircraft, which is a two-engine aircraft, if you happen to lose an engine on take-off all of your concerns have to take in those contingency operations as well."

McLean stresses that all trauma patients will continue to be taken to Victoria Campus, where the helipad is still operational.

And patients going to University Campus will land at London International Airport and be transported by land ambulance to the hospital.