The U.K. Royal Air Force (RAF) is rapidly building up its fleet of modernized CH-47 Chinook transport helicopters upgraded through the £290 million ($450 million) Project Julius program.

Sixteen of the RAF’s 38 Chinook Mk. 2 helicopters have now been updated to the Mk. 4 standard and the first aircraft will shortly be deployed to join the U.K.’s Joint Helicopter Force operating from Camp Bastion in Afghanistan. Several Mk. 4s are already in-theater, having arrived in December 2012 to support special forces operations.

“I wanted aircrews to be able to walk out to any Chinook and fly any mission,” said Capt. David Childs, the head of the Chinook program at the U.K. Defense Ministry’s Defence Equipment & Support (DE&S) agency, speaking to journalists during a briefing on the Salisbury Plain on Aug. 29.

Project Julius aims to standardize the fleet of Chinooks by introducing a new standard avionics suite across the entire fleet. Thales TopDeck was selected, and the system has been used to fit out the flight deck with four new 6 x 8-in. primary flight displays, while tablet computers display mission data not only to the pilots but also for the rear crewmen, who are now taking on a greater role during high-intensity missions. The upgrade also includes the installation of the more-powerful T55-L714 engines, which cope better with hot-and-high conditions.

The challenge for contractors—including Boeing, GE Aviation, Thales, Qinetiq and Vector Aerospace—was that the Chinook fleet is in high demand for operations in Afghanistan and the training needed to support them.

“It was akin to changing the wheel on a car whilst it was driving at 70 mph.,” Childs says, “but we have managed to succeed.” Engineers have managed to speed up the upgrade process, with each aircraft being upgraded in 122 days, half the time taken by the first Mk. 4 update. The rotorcraft are upgraded as they return for major servicing upon return from deployment in Afghanistan. At any one time, five Chinooks will be undergoing upgrade at Vector’s facilities at Fleetlands, Hampshire.

The next step will be to upgrade the fleet of eight Mk. 3 Chinooks, which had been due to enter service in 1998, but contractual issues over avionics software prevented the aircraft from entering service. A shortage of helicopters in Afghanistan prompted an ad hoc program to revert the eight aircraft back to an earlier standard to make them airworthy and available for operations.

Since their entry into service in early 2010, the aircraft were not deployed to the front line but instead held back for operational conversion training, and the fleet has one of the highest availability rates in the Chinook force. These rotorcraft also will be updated through the Julius program, but will need a separate flight-test program because the variant is equipped with the larger extended-range fuel tanks like those fitted to Canada’s CH-147F and the Greek army’s CH-47SD.

These changes affect the location of the aircraft’s landing gear and aerodynamics, requiring some testing, according to program executives. The first Mk. 3 will enter the conversion program at the end of 2014. Once upgraded, the Mk. 3s will become Mk. 5s. It has been suggested that the Mk. 5 capability may eventually be used by U.K. Special Forces for long-range missions, the capability initially envisaged when the U.K. bought the Mk. 3.

The Thales cockpit is also being fitted on the U.K.’s 14 new Chinook Mk. 6s, which are being built by Boeing in Philadelphia. Three of the new model aircraft are now flying and are undergoing flight-testing in the U.S. The first aircraft is due to be delivered to the U.K. at the end of the year, and Childs is hopeful that the Mk. 6 will be the first aircraft to be delivered to the RAF without having to undergo any testing in the U.K.

The rotorcraft will be awarded an initial release-to-service authority once it is delivered, before a full release-to-service is given by the U.K. Military Aviation Authority. The aircraft are currently being flown on the U.S. civil register and have recently been tested at NAS Patuxent River, Md. The Mk. 6s are variants of the CH-47F, and feature a Digital Automatic Flight Control System (Dafcs). The new aircraft also feature a Cobra fire-suppression system, external rescue hoist and a rotor brake. The U.K. Chinook force has expressed an ambition to refit Dafcs across the entire U.K. fleet, although such a move is likely to come at a cost similar to that of the Project Julius program.

Interestingly, the hangars of the U.K.’s new Queen Elizabeth-class aircraft carriers have been modeled to take into account Chinook operations without requiring blade folding. Two Chinooks with unfolded blades can fit onto the ship’s deck lifts. The hangars have also been designed to accommodate the Bell Boeing V-22 Osprey tiltrotor.