HALIFAX — Cracks have been detected in the tails of all but two of the Canadian military's 23 Cyclone helicopters, the Royal Canadian Air Force confirmed Thursday, adding two more aircraft to the previous list.
The cracks were first detected in one of the maritime helicopters during a routine inspection on Nov. 26 at 443 Maritime Helicopter Squadron at Patricia Bay, B.C.
By Dec. 5, the Air Force said it had discovered damage in the same general area on a total of 19 helicopters. At the time, the military said two Cyclones did not appear to have any tail defects and that the remaining two in the fleet were receiving longer-term maintenance and would be inspected at a later date.
On Thursday, a military spokeswoman said cracks were detected in two more aircraft, including one of the two Cyclones that had been initially cleared.
"In one case, the cracks were so small, they were missed in the initial inspection," the spokeswoman said in an email.
Six of the Sikorsky-made aircraft have been repaired and four others were in the repair shop as of Thursday.
The RCAF said Thursday the cause of the cracks had yet to be determined.
"It is certainly something our experts are investigating, given the importance of understanding how this happened and affected so many aircraft in the fleet," Lt.-Col. Adam Thomson said in an email.
Meanwhile, one of the damaged helicopters was to be flown from the deck of the frigate HMCS Winnipeg to Patricia Bay, which is north of Victoria. The warship was returning to its base at Esquimalt, B.C., after completing a four-month tour in the Asia-Pacific region.
"In this specific case, a one-time short ferry flight from the ship to its home base at 443 Squadron, Patricia Bay was authorized, in accordance with a detailed airworthiness review," the Royal Canadian Air Force said in a statement. "Minimal cracking was found on this particular aircraft."
The Air Force has said the cracks are unique for each CH-148 Cyclone, but it has said they are all located on the frames of the aircraft.
The U.S.-based manufacturer of the Cyclones, Sikorsky Aircraft, has devised a fix that involves the installation of reinforcements to provide added strength to the airframe, the military has said. A spokesman for Sikorsky confirmed this week that the cracks were found in the forward portions of the tail cones — the section of the tail closest to the fuselage.
The Cyclone fleet has not technically been grounded or placed on an operational pause, but the military confirmed the damaged aircraft were removed from regular flying duties.
The squadron at Patricia Bay has six Cyclones. The entire fleet is overseen by 12 Wing Shearwater near Halifax, which has 17 of the helicopters.
One Cyclone crashed off the coast of Greece in April 2020, killing all six military members aboard.
In 2004, the Canadian government agreed to pay $3.2 billion for 28 Cyclones, four of which have yet to be delivered.
This report by The Canadian Press was first published Dec. 16, 2021.
Michael MacDonald, The Canadian Press