HMS Queen Elizabeth: Leak found on new aircraft carrier

In previous news [July 10, 2017]: **LINK**

https://ukdefencejournal.org.uk/hms-queen-elizabeth-encounters-propeller-shaft-debris-issue-trials/

MichaelG.

So it's not quite life jackets all round yet?

Dave W

Interesting that damage was first examined at Invergordon, at the head of the Moray Firth. Wonder if she picked up a broken length of wire-cored trawl warp? I live by the Firth, and bits of fishing industry debris are washed up almost daily.

I remember a similar experience from my shipbuilding/marine engineering days 19 the early 1970's during sea trials of the ferry St George. She was experiencing severe vibration, especially when in reverse. It was so bad at the aft end of the ship that in some cabins you couldn't stand comfortably, let alone sleep. I seem to recall that we had a job keeping up with water ingress into the shaft tunnel and the bilge pump was running constantly to keep up with it. It was believed that the welds on one of the hull plates had cracked due to the vibration.

The ship was dry docked immediately on return from her trial and a 25 gallon paint tin was found to be caught either around the shaft or between the variable pitch blade and the prop boss. The plate was welded up and on removal the severe vibration was no longer present.

Listened to a radio news report on the prop shaft leak this morning, the shaft is 7metres diameter, is it? Repeated an hour later so must be.

What sort of seal is it? One of those rubber ones that is lubricated by the water around it? The name of these escapes me at the moment.

John

They still are, even though they are indoors now.

My Mum was a tracer in Portsmouth Dockyard before the war. One of her colleagues was working on the designs for a new warship and caused great amusement by lettering BRAINS FROM SEAMEN'S HEADS on her drawing.

George

The Props are 7m diameter.

**LINK**

The above link doesn't give shaft dia but the flanges on the 2 gearboxes shown estimate to maybe 1.8m and the output shaft to maybe 1m. The prop shafts by inference should probably be the same.

regards Martin

Edited By Martin Kyte on 19/12/2017 11:06:29

If you go to the Rolls Royce website, you will find it is the propellers which are 7 metres in diameter, and not the shafts. Yet another example of modern badly-trained journalists who do not check their facts. The editors who trained me must daily turn in their graves!

Let's hope they find it is all down to a fishing pot that has been poorly marked then perhaps the RYA & Cruising Association will get a few hundred more signatures on its petition **LINK**

Edited By Sam Longley 1 on 19/12/2017 11:19:29

Presumably they spent several hours looking for a rating with a bucket and no-one would volunteer...

Isn't it amazing that the press manages to declare to the whole world our current defensive weakness.

Its not unusual for stern seals to leak during the first few sets of trials, and finding them is what shakedowns are for.

The '45's suffered from exactly the same problem, but that dwindled into insignificance with the 'other' problems that arose.

This leak on a ship of this size is about as significant as a nick in the wiper blade of a new car.

Lofty

Many a true word Joules. I am reminded of a holiday story from my childhood when a rather condescending London visitor hired the local fisherman's rowing boat, having asked if it leaked. He was advised that if it did, he was to " pull out that there bung"

The boat was launched in a lively sea on a steeply shelving gravel beach, not the most elegant launch but adequate and it was rowed away out of sight round the nearby headland. About 15 minutes later it was seen coming back, riding very low in the water and in danger of losing cargo like picnic baskets over the side. It was now of course very ungainly and landing in those conditions was demanding of both timing and buoyancy. Our London visitor got it badly wrong, the boat broached and was dumped broadside on onto the beach

However, he got a round of applause from the beach population as he surfaced with his pipe clamped firmly in his teeth and miraculously it was still alight!

And, yes---he had pulled out the bung!

Brian

Sorry Ady, but that's a Birmingham screwdriver.

Can't match that one, Brian, but a pal was fishing from a boat on Loch Morar, the deepest loch in Scotland. Suddenly his pal exclaimed "Oh, look, there's a Drambuie cork on the floor", and promptly picked it up. My pal only just managed to stop him throwing the cork over the side........

The seal is a two stage graphite/ stellite ring composite assembly with and emergency inflatable nitrile tyre.

And those are the plummer blocks not the gearboxes.

Regards

Lofty

"And those are the plummer blocks not the gearboxes."

Well that makes sense,they did look a little on the small side. The point I was making really is that it took me about 30secs from a standing start with no knowledge of the boat to figure out the size of the props and the general size of the shafting.

Aha some data on the seals too.

I am a little disappionted that when a subject comes up it generates more moan than engineering comment on the forum. Nothing wrong with a moan but it's nice to pick up some information along the way.

regards Martin

I was a Royal Navy Artificer ,Shipwright, the ship is on Sea Trials to sort any snags out,this is a snag, the press as usual just trying to turn run of the mill event into a major catastrophe its a shame they don't what they are talking about, the lads will sort it out just like we always did,Martin makes a good point

Mick

Reminds me of my Dad who was a country bobby in the early 60's complete with pushbike. One day on his regular beat he came across some blokes with the road up and a gas main in the bottom leaking profusely through a hole. The blokes digging the hole didn't know what to do except wait until the gas board arrived. Dad, who was always eminently practical, took a look at the size of the hole, got out his pen knife and whittled a bung out of a green stick from the nearest hedge and managed to stop the leak until the gas men got there.

Another couple of rounds of jute packing into the stuffing-box, surely!