HMS Queen Elizabeth: Leak found on new aircraft carrier

[John MCParticipant @johnmc39344]

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

[GeorgineerParticipant @georgineer]

Posted by Brian Hutchings on 19/12/2017 10:27:27:

Ships in Nelsons time had outside toilets, they were called heads.

Brian

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

[Martin KyteParticipant @martinkyte99762]

Posted by John MC on 19/12/2017 10:49:22:

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

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

[MikeParticipant @mike89748]

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!

[Sam Longley 1Participant @samlongley1]

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

[Neil WyattModerator @neilwyatt]

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

[FMESParticipant @fmes]

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

[Brian WoodParticipant @brianwood45127]

Posted by Joules Beech on 19/12/2017 09:26:37:

Can't they drill a hole to let the water out !!!

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

[Dave HalfordParticipant @davehalford22513]

by Ady1 on 19/12/2017 10:03:03:

An old Navy guy would just give it a few taps with a Coventry spanner on the night watch

The modern navy guys will probbly spend a couple of million sorting it out

Edited By Ady1 on 19/12/2017 10:07:46

Sorry Ady, but that's a Birmingham screwdriver.

[MikeParticipant @mike89748]

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……..

[FMESParticipant @fmes]

Posted by Martin Kyte on 19/12/2017 11:05:31:

Posted by John MC on 19/12/2017 10:49:22:

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

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

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

[David ColwillParticipant @davidcolwill19261]

Posted by Georgineer on 19/12/2017 10:57:30:

Posted by Brian Hutchings on 19/12/2017 10:27:27:

Ships in Nelsons time had outside toilets, they were called heads.

Brian

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

They are not outside the ship though!

[Martin KyteParticipant @martinkyte99762]

"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

[Mick HenshallParticipant @mickhenshall99321]

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

[Jon GibbsParticipant @jongibbs59756]

Posted by Mike on 19/12/2017 12:01:23:

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……..

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.

[Mick B1Participant @mickb1]

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

[John ReeseParticipant @johnreese12848]

I share your opinions of modern so-called journalists. They don't know anything. They don't research anything. They sensationalize everything. They ae the same here in the US.

[MWParticipant @mw27036]

Posted by John Reese on 19/12/2017 15:56:58:

I share your opinions of modern so-called journalists. They don't know anything. They don't research anything. They sensationalize everything. They ae the same here in the US.

Exactly, these problems happen all the time, yet because this is the big cheese at the moment, they've gone over with a fine tooth comb to look at any flaws.

Do you think they would've bothered reporting a leak on a ship in WW2 when plenty are being blown to smitherines, I wonder. 

 

 

Edited By Michael-w on 19/12/2017 16:25:07

[SillyOldDufferModerator @sillyoldduffer]

Posted by David Colwill on 19/12/2017 12:07:03:

Posted by Georgineer on 19/12/2017 10:57:30:

Posted by Brian Hutchings on 19/12/2017 10:27:27:

Ships in Nelsons time had outside toilets, they were called heads.

Brian

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

They are not outside the ship though!

Jon Pertwee was yarning on 'Tell Me Another' the other day about his time in the Navy. (Programme from the 1970s repeated on TalkingPictures)

Pertwee served on HMS Hood where the Seamen's Heads were at the front. He quickly learned that using the heads on a fast battle-cruiser in rough weather required judgement. The plumbing backed up spectacularly whenever the bow ploughed into a wave…

Dave

[Chris TriceParticipant @christrice43267]

"200 litres of sea water per hour". I would think waves and rainwater would far exceed that figure in bad weather.

[CrocadillopigParticipant @crocadillopig]

Although It doesn't sound critical and can be easily fixed it could be expensive if she has to dock down and de-store to repair. I remember being deployed on the Invincible when The propeller shaft 'A' bracket bearing needed replacing it took several attempts to fix in dry dock. Nearest place was Singapore (Oh what a Shame)

Russ

[ChrisHParticipant @chrish]

In the merchant navy they years ago gave away the idea of a wood lined tube, lubricated by sea water, sealed by a packed gland to keep most of the sea outside the ship, to support the prop shaft as it exited the ship. They were replaced with (very well) sealed tubes containing a totally oil filled bearing under a considerable head of oil. Therefore absolutely no sea water through it at all. If sea water was leaking through that shaft bearing and seal you were definitely in the mire! Hope this is not the case here but suspect so.

Chris

[Neil WyattModerator @neilwyatt]

Posted by John Reese on 19/12/2017 15:56:58:

I share your opinions of modern so-called journalists. They don't know anything. They don't research anything. They sensationalize everything. They ae the same here in the US.

Does that include me…?

N.

[doubletopParticipant @doubletop]

Its undergoing sea trials, which is about testing all the systems.

After being told many times in the RAF, "just get it tested and flying again". I'd point out that the main purpose of testing was to find out what isn't working, not necessarily to find out what is working. Therefore, the assumption must be something could be wrong that will require fixing, which will take time.

In fact, if you test something and don't find a problem you must seriously consider if your test plan is flawed.

So the Navy have been testing and found a problem. Good job!! Now a case of doing the risk analysis, and deciding whether to fix the seal, re-design and fix all the other seals as well, install bigger pumps, monitor or just ignore.

Pete

[MikeParticipant @mike89748]

No, it doesn't include you, Neil. Just looked you up on Linkedin – what an interesting career!

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