Pace quickens on carrier assembly

Guest bloggerACA Engineering DirectorDavid is employed by BAE Systems, and is responsible for all the engineering work being carried out on the QE Class programme. Previously, he was design manager for HMS Ocean, Albion and Bulwark, and was chief engineer on the Type 45 Destroyer programme

I am writing this after what was a pretty significant weekend for the project. A major evolution has taken place in the building dock at Babcock’s Rosyth facility that signals the start of dock cycle B, during which the assembly of the constituent parts of the forward half of HMS Queen Elizabeth will take place. Within a few months we will have more than half the giant aircraft carrier assembled in the dock. Once assembled this will really open up the opportunities for setting to work and commissioning the systems and bringing the ship to life.

On June 8 the dry dock was flooded and Super Block 03 (SB03), the centre section of the ship, was gently floated up. On June 9 SB03 was manoeuvred out of the dock and across the non-tidal basin where she was moored against the west wall, near where Lower Block 02 (LB02) containing the forward machinery spaces was moored after completing its 600 mile journey from Portsmouth.

LB02
LB02, containing the forward machinery spaces, arrives at Rosyth

For the first time in nearly a year, and the last time for over a year, the dock was empty, but not for long. The same afternoon LB02 was manoeuvred into the dock followed by SB03 and on June 9 the dock was drained and both the blocks docked down. It is particularly important that LB02 was accurately located as she docked down as all the other assemblies will be aligned to LB02.

The next step will see the bow section craned into the dock and located ready for welding the butt to the forward end of LB02. Dimensional control measurements have been taken of the forward end of LB02 and LB01 has already been trimmed to match. A couple of weeks after that SB03 will be skidded along the dock bottom to align with the aft end of LB02 and the butt welded up.

Progressively over the next few months the centre blocks and sponsons will be craned onto LB02 and LB01 and consolidated and finally the forward island structure will be craned onto the top. This will mean that the important links between the radars and sensors on the island and the operations rooms in the main hull can be completed and setting to work of the Mission Systems can be got underway. The de-risking work that has been done in the various shore development sites will then really show its value.

LB02 dock
LB02 eases into the flooded dock

But I am getting ahead of myself, the evolutions have gone very smoothly which is a tribute to all the hard work that has gone into the planning and preparation. Undocking, docking and manoeuvring of completed ships with all their facilities onboard and power available is relatively routine work, but the same task with incomplete blocks of ship with no power, or people on board and rather awkward shapes brings its own challenges. SB03 for instance is approximately as wide as it is long with significant overhanging structures on either side.

As SB03 transited across the non-tidal basin we were able to get a different perspective of it from the largely two dimensional view in the dock, while the graceful shape of LB02 moored in the basin really starts to show how the completed aircraft carrier will look.

While walking around the dockyard at Rosyth it seems that almost every conceivable space is a parking place for another significant part of aircraft carrier, from the bulbous bow of ship 02 HMS Prince of Wales through to the transom of HMS Queen Elizabeth complete with its stern boarding platform.

Lower Block 02 was built at the BAE Systems yard at Portsmouth and in late May it was loaded out onto a semi-submersible barge and towed North to Babcock’s Rosyth dockyard, where similarly to LB03 before hand the barge was submerged and grounded on the bottom of the Firth of Forth allowing the block to be floated off. The operations all going very smoothly thanks to some very hard work by the transportation team. LB02 has reached an advanced state of completion before leaving Portsmouth, including having live switchboards as I reported in my last blog, and is in an extremely good condition which the team at Portsmouth can be very proud of. They are now eagerly awaiting the joints to other blocks forward, aft and above to be completed so that work can be completed across the boundaries.

Also at the end of May the five constituent parts of Centre Block 02 were shipped up from Cammell Laird’s yard at Birkenhead. These blocks have also reached a very high degree of completion, except where outfit has had to be limited to avoid exceeding the weight that can be lifted by the Goliath crane. The level of finish in these blocks is extremely good and many of the compartments look to be completely finished.

Cammell
The five sections of Centre Block 02 arrive from Cammell Laird shipyard

As happened with the transportation of LB03 from Govan to Rosyth, a charity cycle ride was arranged in which a team of enthusiastic cyclists cycled from Portsmouth to Rosyth in a challenge to “beat the block” as LB02 took its journey by sea. This was quite an epic event with over 50 cyclists taking part in the 500 mile cycle ride over a 5 day period, and has raised thousands of pounds for the Royal Navy and Royal Marines charity. My wife and I did the first 57 miles from Portsmouth to Reading on our tandem and I take my hat off to those who completed the whole way and in particular to a small band, who not content with finishing at Rosyth continued up to John O’Groats.

So this has been a very successful period for the project and progress will become increasingly visible now as we move forward through Dock Cycle B.