One of the smaller engineering challenges the PIPE team have had to overcome is one of keeping the noise level safe in the Transmission Room whilst providing the correct levels of cooling. The room is a concrete box with 150kw of cooling provided by 3 Citec 50kw units. To further add to the complexity, the room doesn't have any raised floor, meaning the units push the cold air out of the top, rather than the bottom. Because everything is tightly spaced, the 'day n' designed air conditioning needed to be installed 'day 1'.

When the units were commissioned, they were noise tested and found to be just inside the safe working limits and too loud for a telephone conversation. To solve this, the PIPE team engaged a local specialist to build a set of baffles to turn the air through 90 degrees as well as split it. The solution has worked a treat and you are now able to safely work in the room without ear protection AND hold a conversation on the inter-station telephone system!

This photo is the S1.1 joint going over after we had recovered the buoy.

The Tyco Durable is currently back in port in Sydney. After all repairs are complete and we have our new plough team on board we will complete the remainder of the burial of S1.1 off Sydney. We will then inspect and post-lay bury as required the Sydney shallow water cable. We expect this (with no weather delays) to take less than a week to complete and then we will continue laying from Brisbane north.

The Tyco Durable has now completed S1.2 between Brisbane and Sydney. This included the deployment of BU1 in 4500 metres of water off Sydney and as part of this the deployment of the S2 stub for future connection to New Zealand.

This photo was a buoy we laid that had the Sydney end of the cable attached while we went further east to deploy the stub cable. We took this photo as we were returning to pick up the buoy to join it to the BU. The Tyco Durable has now returned to Sydney to have the winch repaired and reload the plough team.

It has been an interesting few weeks for the Tyco Durable as we lay the remaining portion of PPC-1 up the Australian coast. We have had some tricky weather for ploughing, namely a severe storm on 21st May. As some of you may be aware, we have had some equipment problems, specifically the large tow winch for the plough needs spare parts and major repairs in order for us to complete the ploughing off Sydney.

Despite these setbacks we have continued on and have laid BU1 off Sydney and all of the cable between Sydney and the BU2 location (Brisbane). We are currently 170km to the east of the Brisbane CBD streaming the last of the segment from Sydney.

The plan is for the ship to return to Sydney today to complete the winch repairs and then the remaining Sydney burial works before returning to pick up where we have left off and continue the final parts of the lay up to the final splice position off Madang.

 

Photo courtesy of James Freeman of the Nautical Association of Australia

It is an engineering requirement that the PPC-1 Cable Station transmission equipment racks are NEBS zone 4 compliant.

The Telecordia NEBS standard defines the industry standard for seismic testing methods and tolerances. These are applicable for communication equipment racks or cabinets which are likely to be deployed in areas where substantial seismic activity is a possibility.

Following the recommendations defined with the NEBS standard, during rack manufactures' seismic testing programs the rack or cabinet is typically attached to a test concrete slab, loaded with simulated equipment weight and then subjected to a shake test. At its basic level if the rack falls down or distorts past defined tolerances it simply fails the test. In most cases when this occurs the design of the rack has to be stiffened or its specified carrying weight reduced.

Earthquake simulations are basically a series of changes in velocity and acceleration from one vector to another. NEBS Zone 4 seismic testing replicates earthquake scenarios measured on the Richter Scale of 8.3 in magnitude

This video from Chatsworth Products Inc shows clips from the tests of their Zone 4 rated 19" wide rack with 6" deep rails. The rack version tested here is to be installed within the PPC-1 Cable Landing Stations.

As a part of the Tyco Telecom turnkey scope, 20 days of training are provided at key points during the project. Back in January, Matt and John attended the ‘Type A' training in New Jersey. This time it was ‘Type B1' in the Sydney CLS.

The ‘B' training (of which there are 3 separate courses of 5 days each) take place in each of the cable stations. These photos were taken during Sydney's 5-day course. In them you can see Matt and John practising the removal of components from the system. It's important to understand how/when such work would need to be done as well as following correct procedures (cleaning, ESD, console commands). The course was a success with the guys getting their first ‘hands-on' taste of managing the PPC-1 network. Training has already been completed in Guam and the Tyco Telecom trainer is currently in Papua New Guinea working with the Telikom staff.

‘Type B2' training will take place in all stations later in the year, once the cable has been laid. ‘Type B3' will be conducted only in Sydney as it's more aimed towards the NOC staff, rather than the station technicians.

During the lay, the system is powered up to allow Tyco Telecom to continuously monitor the cable and optical bodies for problems. As the repeaters contain a significant number of electrical and optical components, they need to be kept cool. This is normally done by the sea but whilst on the ship, it needs to be done with a continuous blast of air conditioning.

The repeater stacks are covered with insulating blankets and the air conditioning ducts are fed underneath the stack. Whenever a repeater is prepared for deployment, the power is turned off for safety reasons. This means that the repeater can cope being outside of the stack before it goes overboard.

(Photo by: Tom Kleindinst, Woods Hole Oceanographic Institution )

It was interesting to read about the Nereus, a robotic sub which has reached the deepest known part of the ocean, the Marianus Trench, where the PPC-1 cable is laid.  The Nereus is remotely operated by a lightweight, fibre optic cable which also streams real time video and data from the ROV back to the ship. Unlike PPC-1 however, which is approximately 20mm in diameter, the tether on the Nereus is the diameter of a human hair covered by a thin protective jacket of plastic. The Nereus completed the dive to 10,902m - deeper than where the PPC-1 cable is laid at 9440m. 

Read more about it here.
Read about PPC-1 crossing the Marianas Trench here.

The main site for cable operations on the cable ship is the Cable Highway (which can also be called the Centre Castle). The cable tanks that hold the cable before it is deployed are underneath with their openings in the floor of the Highway. Aft of the Highway is the Stern deck where the plough is stored when not in use. At the very end of the stern deck are the Sheaves. The Sheaves are cutaway sections that provide the path off the ship for the cable.

Along the port side of the Highway are the repeater stacks and along the starboard side are a series of workshops and control rooms: transmission test room, jointing and splicing workshops as well as the Linear Cable Engine control room.

The highway is busy 24hrs a day (as you can imagine) as the crew work to deploy the cable and manoeuvre the optical bodies in to position on the trackway. There's no stopping the cable during normal operations and so their work has to be timed like clockwork to ensure nothing goes wrong!

 

Edit: Typo/accuracy