Now crash investigators are appealing to all operators of the particular aircraft to contact them as soon as possible if they have experienced anything similar.
On Saturday, June 12, Mahdi Zougub and Fay El Hanafy married at Terrace Downs resort about 80km from Christchurch.
They then went up in a Robinson R44 helicopter to have photos taken.
Shortly after takeoff the engine lost power and the helicopter plunged to the ground.
Zougub and El Hanafy were both badly injured, along with the pilot and wedding photographer Rachel Jordan.
All four remain in hospital in stable but serious conditions.
Helicopter owners Wyndon Aviation last week confirmed the crash was the result of the engine losing power.
They are still working to establish how that happened.
The Civil Aviation Authority is also investigating and today confirmed they had reached out to all R44 II owners in New Zealand - as per the CAA aircraft register - appealing for any relevant information.
The email was sent after the CAA heard of another R44 II that lost power in a similar way.
They provided a copy of the email to the Herald.
"The initial investigation carried out by the CAA in conjunction with the aircraft operator and the maintenance provider has revealed that a probable engine total power loss occurred, while the engine was operating at high power during climb-out," the email stated.
"The CAA has been made aware of an anecdotal occurrence in New Zealand involving a Robinson R44 II helicopter, where the engine suddenly lost power while on approach to land.
"The maintenance investigation failed to find the apparent cause of the engine power loss.
"The CAA requests operators of Robinson R44 II helicopters fitted with the Lycoming IO-540 engine, who may have experienced similar engine power loss issues, to please contact the CAA as soon as practicable."
"Our Investigation and Response team is continuing with its inquiry into the cause of the 12 June accident.
"During the course of our investigation we have been alerted to an instance where the pilot of another R44 II aircraft apparently experienced some sort of engine power loss while approaching to land.
"This incident wasn't classed as an accident because the aircraft was able to land safely at the time.
"A subsequent maintenance investigation was unable to identify the cause of the engine power loss in that instance."
The spokesperson said once the CAA was made aware of the earlier occurrence, all owners of R44 II aircraft "fitted with the same model of engine" in New Zealand were contacted.
"Our team is working through this investigation thoroughly and methodically, and are working to gather as much information as they can about factors which may have contributed to the sudden power loss," the spokesperson said.
"Information about any power loss issues other operators have encountered could be invaluable in helping us to understand the root cause of the engine power loss and subsequent accident on 12 June."
Anyone with information could email investigations@caa.govt.nz.
The CAA has also requested photos taken by Jordan during the ill-fated flight.
