The Queen Elizabeth-class, or QE-class, will be the centrepiece of Britain’s defence capability for the 21st century. Each 65,000tonne aircraft carrier will provide the armed forces with an operating base that can be deployed anywhere around the world. Operating the Joint Strike Fighter Lightning II jets (see box) and a number of types of helicopter, the QE-class will be versatile enough to be used across the full spectrum of military activity from warfighting to providing humanitarian aid and disaster relief.
Among a number of recent milestones, the Aircraft Carrier Alliance recently completed installation of the second MT30 gas turbine alternator (GTA) into the Royal Navy’s second aircraft carrier in the QE-class HMS Prince of Wales. Generating 36MW, each 120tonne GTA package consists of a GE-supplied alternator coupled to a Rolls-Royce-supplied MT30 gas turbine contained within an enclosure. Two MT30s, the first of which was installed in early 2015, are installed in each ship and will provide two thirds of the 109MW.
The installation involved lifting the MT30 gas turbine and associated ancillary equipment housed in a steel package known as the gas turbine enclosure onto the ship structure. With the enclosure in place, the large alternator, which is driven by the gas turbine to produce electrical power, was then hoisted into place. Once operational, the GTAs will supply high voltage (HV) power to the four propulsion motors as well as the 13 ship service transformers. These transformers distribute low voltage (LV) power to the weapons systems, mission systems equipment and navigation systems, as well as power to the hotel services required to run the QE-class.
Installation of the ship’s blown fibre optical cable plant (BFOCP) commenced during October. It is designed to transfer data from multiple sources throughout the platform and mission systems. Taking on board some important lessons which were learnt from work on the first-of-class, HMS Queen Elizabeth, particularly around preparation and scheduling, installation commenced in Damage Control Zone 2 and was quickly followed by similar commencement in Damage Control Zone 3. Following successful installation audits on 29 October, endorsement was given to connect shore-supplied low voltage (440v) via shore connection boxes to Damage Control Zone 3 LV switchboards in compartments 5LC5 and 5LC4 for the first time since they were factory tested just over four years ago. This allowed the HMS Prince of Wales commissioning team, supported by Rolls-Royce and the wider power and propulsion sub alliance, to start electrical commissioning with work now to progress from the switchboards to the electrical distribution centre’s, initially within Damage Control Zone 3.
The start of low-voltage commissioning is a notable step forward in bringing HMS Prince of Wales to life. Proving the 440v electrical distribution system from LV switchboards to ‘end users’ is a prerequisite to having the ship generate and distribute its own power.
A cutting-edge 3D radar system said to be capable of detecting objects as small as a tennis ball travelling at three times the speed of sound has been installed on HMS Queen Elizabeth. Known as ‘Artisan’ 3D radar, it was installed in late September, marking another major milestone in the preparation for sea trials.
The Artisan radar, which was designed and developed by BAE Systems, can monitor more than 800 objects simultaneously from 200m to 200,000m whilst cutting through radio interference. The radar system has already proven its capability to deliver air defence and anti-ship operations on the Type 23 frigate and helicopter carrier.
Les Gregory, Director for Products and Training Services at BAE Systems said: “Artisan is a ground-breaking radar system that delivers real capability to the Royal Navy in its supreme accuracy and uncompromising tracking. In addition, its world-leading electronic protection measure ensures that even the most complex of jammers will not reduce its effectiveness. We have already seen the radar perform excellently on the Type 23 frigates and are proud to be able to bring this advanced technology to the Royal Navy’s new aircraft carriers utilising its air traffic management capability for the first time.”
Preparations to install the radar system on HMS Queen Elizabeth took two-and-a-half years with engineers from BAE Systems working closely with the Ministry of Defence. Part of this work included creating a life-sized mock-up of the carriers’ aft island in Cowes which was used to hone the radar’s interaction with the combat systems on-board the QE-Class carriers, to deliver an optimal integrated solution.
In November 2015, GE announced details of a partnership with VolkerStevin Ltd to provide technical solutions to the Defence Infrastructure Organisation (DIO) that will see GE design, manufacture and commission a Rotary Frequency Converter (RFC) which enables efficient, safe and reliable power transfer from the national grid to HMS Queen Elizabeth.
The electricity from the UK national grid, which operates at a frequency of 50Hz, will be converted by the RFC into 60Hz for use by the equipment on-board the aircraft carrier. This allows for the ship’s diesel generators to be switched off whilst at berth in Portsmouth Naval Base, reducing noise, pollution and costs. GE Marine’s RFC solution consists of a motor, generator, a static excitation system, a synchronous frequency convertor and associated equipment.
It was also announced in November that Britain is to speed up acquisition of new fighter jets for the carriers. The decision to do so was part of the UK’s Strategic Defence and Security Review, and means that the UK will have 24 F-35 Lightning II Joint Strike Fighter aircraft available on its two new aircraft carriers by 2023.