The new monitoring system aims to improve emergency response times
A surveillance system that can pinpoint the positions of North Sea helicopters has been launched in Aberdeen.
The system could help avoid "near miss" incidents and aid in locating aircraft in the event of an emergency.
Industry body Oil and Gas UK said it was the first time such a system was being used for offshore operations
Earlier this year the use of personal locator beacons was suspended because of fears they could interfere with onboard signalling systems.
A safety review suggested they had hindered the rescue operation when a Super Puma helicopter ditched in the North Sea in February.
All 18 people on board survived the crash, but six weeks later another Super Puma crashed, killing all 16 crew and passengers.
The new "multilateration" monitoring system is a joint initiative by Oil and Gas UK and National Air Traffic Services Ltd (Nats).
The system will be fitted to 16 offshore platforms.
As soon as a helicopter goes beyond the 80-mile zone covered by land-based radar, its signal is picked up by the offshore platforms, with the data then returned to the airport.
Bob Keiller, chairman of the Helicopter Task Group, said: "This new system, a key work area of the task group, is a breakthrough in helicopter safety, and it is encouraging to see it going live."
Iain Harris, head of engineering for Nats, said: "It has been a challenging project to manage due to the complexities of installing equipment offshore and the sheer number of stakeholders that were involved in delivering the surveillance and voice communications improvements for the 25,000 square miles of airspace over the North Sea."
Robert Paterson, health, safety and employment issues director with Oil and Gas UK, added: "Improving radar and radio coverage for helicopter flights is a big step forward."
Trials of the system are under way, with all 16 platforms expected to be fitted with the equipment by next June.