The federal government has signed a deal it says will result in the delivery of the long-delayed CH-148 Cyclone helicopters beginning next year.

The announcement of undisclosed contract amendments with Sikorsky Aircraft — a division of United Technologies — came Wednesday.

United Technologies says the amendment clears the way for the delivery of the 28 aircraft under the $5.7-billion program.

It's the second time the government has negotiated a contract amendment with Sikorsky, which has missed previous deadlines.

The Cyclone program, which originally anticipated the first helicopter being delivered in 2008, was meant to catch up to the 1993 procurement of EH-101 helicopters, ordered by the Mulroney government, but cancelled in 1993 by former prime minister Jean Chretien.

At the time the Liberals committed to the Cyclones, the helicopter was still in the development stage, being upgraded to military specifications from the less rugged civilian variant.

It's an aspect the auditor general harshly criticized in 2010.

The conversion challenges — coupled with changes imposed by the Canadian air force — prompted a thorough redesign of the aircraft. It led Sikorsky to miss several delivery deadlines, including one in 2012 to provide five "interim" helicopters, which would have been used for flight test and training purposes.