November 4, 2021

UK Trafalgar-class Submarine Reactor End Leaks

A famous nuclear submarines for Australia exponent has apparently suggested Australia actually buy aging UK Trafalgar-class nuclear submarines

Beware, submarine reactors and the complex pipes connected to them, wear out, sometimes needing urgent inspection.

Trafalgar-class Service Problems

"In 1998, [HMS] Trenchant experienced a steam leak, forcing the crew to shut down the nuclear reactor. [HMS Trenchant suffered an earlier seafloor accident off Australia's west coast in 1997]. 

In 2000 a leak in the PWR1 reactor primary cooling circuit was discovered on [HMSTireless, forcing her to proceed to Gibraltar on diesel power.[17] The fault was found to be due to thermal fatigue cracks, requiring the other Trafalgar-class boats, and some of the remaining Swiftsure-class boats, to be urgently inspected and if necessary modified.[17]

In 2013 the UK Defence Nuclear Safety Regulator [see nuclear "hazards"reported that the reactor systems were suffering increasing technical problems due to ageing, requiring effective management. An example was that [HMS] Tireless had had a small radioactive coolant leak for eight days in February 2013.[18]"


From UK Government reports via 
Wikipedia and the The Guardian

5 comments:

Anonymous said...

Hi Pete
The Astute in its present form has also a potential problem area due to its reliance on the PWR2
This reactor will not be used anymore and I understand that this is essentially for safety reason. The last Astute (Agincourt..)will be equipped in 2026/2028(to be confirmed..) with the PWR3 in development with US technology for the novel SSBN Dreadnought

The problems of the PWR2 are twofold:

- a microsopic/Very small leak in the primary (a class 0 incident gravity ..1 to 5 scale of gravity, shut down expressed in "weeks"..) in civilian PWR becomes with the "seal for life" route very complex not only because the sub has to be opened up but also because the radiation proof/shielded equipment,processes, training.. are not in place. Hence HMS in drydock since 2015
- a basic older design that could fare very poorly facing various failure modes (this Guardian article)

https://www.theguardian.com/uk/2011/mar/23/navy-submarines-nuclear-reactors

As the NYT article infers such reactor would not be approved in a "civilian "context
Good luck with the Australian public /political impact !

Getting US Virginia is in my opinion the only realistic route. How ? When? Where? are the next questions

Anonymous said...

Pete
I made a mistake there is 8 levels of incidents in the now standart AEIA gravity scale ,from 0 to 7 ( and not 0 to 5 as I wrote previously today)

Pete said...

Hi Anonymous

Thanks for your Nov 4, 2021, 11:53:00 PM and Nov 5, 2021, 7:45:00 AM

I intend to use them for an article on Tuesday (assuming no submarines disasters over the weekend).

I assume by "HMS in drydock" you mean Vanguard

and by "As the NYT article infers" you mean https://www.theguardian.com/uk/2011/mar/23/navy-submarines-nuclear-reactors .

Regards

Pete

Anonymous said...

hi Pete
This is the 2018 report mentionned in the NYT article
https://www.nao.org.uk/report/the-defence-nuclear-enterprise-a-landscape-review/

page 19 on the PWR2 issue
page 43 on the accute lack of skilled people (from engineering dpt t subcontactor to actual crew).The root cause of many problems. In my opinion building subs ,"a fortiori"nuclear one ,is like running on a bicycle, you cant really afford stop and go for political reasons or budget issue every 5 years.
page 47 points to the lack of infrastructure for maintenance(only one D dock for SSBN), decommissioning safely ect

Although not as dramatic similar situations are found in the US and in France. In the latter case the Cours des Comptes(French equivalent of the UK NAO) and the Fr Senate published a similar report about costs and delays overrun on the Fr deterrent programm.
The Suffren (Barracuda class) is three years late into Service for exemple..

As in most defense programme the yearly budget cuts (defense people do not demonstrate in the street...) result in delays but also costlier programme overall

Pete said...

Thanks Anonymous [Nov 5, 2021, 8:50:00 PM]

The UK Report and your comments are very useful indeed.

Regards

Pete