Diesel S Boat Query.

[janner]

What are the two circular things forward of the after periscope? My suggestion is that they are engine room telegraphs. This is a pic. of Submarine Spitefulls bridge.

 

[WreckerL]

I would agree with you there janner.

 

[guns1969]

As a mere skimmer, may I suggest they could be used for taking on fresh water/fuel.

 

[BreathingOutOnTheWayUp]

Alternatively:

a. Remote layer & trainer for the foredeck gun,

or

b. Remote foreplanes & after planes controls for running 'shallow' or trimmed down.

 

[Topstop]

 

[WreckerL]

As a mere skimmer, may I suggest they could be used for taking on fresh water/fuel.

I can't see how that would work.

Alternatively:

a. Remote layer & trainer for the foredeck gun,

or

b. Remote foreplanes & after planes controls for running 'shallow' or trimmed down.

As above, I can't see how that would work for either or why you would need to remotely operate the gun or the planes. They look like smaller versions of the engine room telegraphs we had on the Rusty B, which is why I agree with janners hypothesis.

 

[dapperdunn]

It could be the end of a really big pair of binoculars

 

[huwshpis]

@WreckerL, I think you and Janner are probably right, but I'm puzzled by one thing. RN practice (and that of, for example, Cunard) was to have 2 telegraphs per shaft, one for power and direction (slow, half, full ahead/astern) and one for the number of revolutions. I can't make out a revolutions telegraph for either shaft in the photo.

 

[huwshpis]

This is similar:

https://www.trinitymarine.co.uk/shop/chadburns-engine-room-telegraph-from-hms-llandaff/

 

[janner]

Just had a email back from Eric Andrews, He was Scratcher on the Sidon (same class of Boat for those that don't know) in his opinion they are the engine room telegraphs. Huw, I don't remember Diesel Boats having the Rev counters/indicators.

 

[huwshpis]

Just had a email back from Eric Andrews, He was Scratcher on the Sidon (same class of Boat for those that don't know) in his opinion they are the engine room telegraphs. Huw, I don't remember Diesel Boats having the Rev counters/indicators.

Thanks, @janner. I did one trip on an 'O' boat as a passenger in the very early 80's and can't remember (if I ever knew) about the telegraphs. I did, however, find a combined telegraph for sale on ebay for £1950 this morning.

https://www.ebay.co.uk/itm/Bronze-Ships-Engine-Revolution-Telegraph-by-Chadburn/301081456164?hash=item4619da6e24:g:IDMAAOxy79JRicIH

The seller is apparently in Pompey Dockyard

 

[janner]

Boats had very small dials by the helm, if you haven't visited the Historic Dockyard it's well worth a look, with several different museums under the one roof so to speak, Royal Marines Museum is moving in as well. There is a large shop selling all sorts of Naval stuff.

 

[Polto]

@WreckerL, I think you and Janner are probably right, but I'm puzzled by one thing. RN practice (and that of, for example, Cunard) was to have 2 telegraphs per shaft, one for power and direction (slow, half, full ahead/astern) and one for the number of revolutions. I can't make out a revolutions telegraph for either shaft in the photo.

I'm sure on O boats we used to have standard revs that we would set for slow and half. The rev order indicator came later I seem to remember. For example, when in the motor room and receiving the order 'half ahead' we used to adjust the revs to what ever half ahead was in the relevant group. Group up 250, Group down 160 (can't recall the actual figures but somebody will be along to correct me in due course hopefully!)

 

[WreckerL]

On Nuclear S boats, as a throttle jockey, the routine was Slow Ahead/Astern was 15 revs, Half Ahead/Astern was anywhere between 0 and max chat and Full Ahead/Astern was Holy sheet, we're about to hit something/be hit/flooding etc etc.

Same as with Polto, Engine order first, then revs, although if Slow Ahead received, rev orders were ignored until Half Ahead received.

 

[Taztiff]

Thanks, @janner. I did one trip on an 'O' boat as a passenger in the very early 80's and can't remember (if I ever knew) about the telegraphs. I did, however, find a combined telegraph for sale on ebay for £1950 this morning.

https://www.ebay.co.uk/itm/Bronze-Ships-Engine-Revolution-Telegraph-by-Chadburn/301081456164?hash=item4619da6e24:g:IDMAAOxy79JRicIH

The seller is apparently in Pompey Dockyard

The seller is also selling this:
https://www.ebay.co.uk/itm/Framed-Letter-By-Lord-Nelson-Signed-And-Dated-1805/292324109967?_trkparms=aid=555018&algo=PL.SIM&ao=2&asc=43781&meid=37bc0ee3ad634e3a9644d9f41aa6f654&pid=100005&rk=3&rkt=6&sd=272810791815&itm=292324109967&_trksid=p2047675.c100005.m1851
Why is this allowed? Surely that is a historical document and therefore should belong to the nation?

 

[dapperdunn]

The seller is also selling this:
https://www.ebay.co.uk/itm/Framed-Letter-By-Lord-Nelson-Signed-And-Dated-1805/292324109967?_trkparms=aid=555018&algo=PL.SIM&ao=2&asc=43781&meid=37bc0ee3ad634e3a9644d9f41aa6f654&pid=100005&rk=3&rkt=6&sd=272810791815&itm=292324109967&_trksid=p2047675.c100005.m1851
Why is this allowed? Surely that is a historical document and therefore should belong to the nation?

I guess the letter belongs to the decedents of Richard Oglesby, to whom it was addressed

 

[St George]

Definitely Engine Telegraphs, when thy moved so did the pair over the wheel position below.
Manned by Sparkers (Telegraphists then) at Harbour stations

 

[PedlarP]

I'm sure on O boats we used to have standard revs that we would set for slow and half. The rev order indicator came later I seem to remember. For example, when in the motor room and receiving the order 'half ahead' we used to adjust the revs to what ever half ahead was in the relevant group. Group up 250, Group down 160 (can't recall the actual figures but somebody will be along to correct me in due course hopefully!)

On an Oberon, slow ahead was determined by 'full field' (35 amps) and full ahead was determined by maximum armature current (1650 amps) so the revs obtained at slow or full ahead in any Group was dependent on the state of the battery charge. As Polto states, for half ahead there were standard revs.
Half Group Down was 150 revs.
Half Group Up was 250 revs, and
Half Batts-in-Series was 350 revs (only sustainable for short periods of time).
Also as Polto mentioned, the Rev Order Indicator came later which gave the CO/OOW additional rev options I.E when returning to PD normally 180 revs was set.
During surface running, opened up, floating the load you could achieve around 275 to 285 revs dependent on battery charge.
Gen dit...the fastest I ever went on an 'O' boat was heading to Montreal up the St Lawrence around '84. We had 320 rpm on both main motors, both donks turning and burning at 4/5th load and we were discharging 250 amps each battery. With a fast inflow current heading down the river and pushing us along we reached about 18 knots (20.7mph).