Visual Detection and Identification of Surface Ships

[JMB1943]

I have been thinking about the various naval engagements of the Great War, and not being caught unawares.

Inevitably, I have to ask some pretty basic questions.

Before the days of ship-borne radar, and in the absence of spotter aircraft, what was the longest range at which a surface vessel (NOT a surfaced submarine) could be detected under ideal (profile view/calm sea/bright sunshine etc) conditions?

Was "dazzle paint" camouflage used on naval vessels during the Great War?

Under ideal conditions, presumably the smoke plume would be the giveaway.

Which class of HM Ships provided the greatest height above sea-level for the lookout post?

What power binocular would the lookout have?

Similarly, what was the longest range at which the class of a surface vessel (mine-hunter/destroyer/cruiser/battleship etc) could be identified definitively?

What power binocular would have been required for identification?

Regards,

JMB

 

 

 

 

Edited Monday at 18:24 by JMB1943
typo

[KizmeRD]

Presume you are asking about one surface vessel’s ability to detect another. In the days of coal burning steamships, as you surmise, smoke plumes from the funnel(s) were often a give-away. In daylight with clear skies a lookout with standard 7x50 binoculars could probably detect a large warship on the skyline at a maximum range of about 20 miles, but much depends on height of the observer and the size of the target ship (due to curvature of the earth). Obviously, in low light and in bad weather, the ability of a ship to visually detect another diminishes, and big ships had enhanced optics not only for lookouts, but for gunnery purposes also.

And yes, dazzle paint was a WW1 invention, and the largest (tallest) warships were of course the battleships and battle-cruisers.

MB

 

 

Edited 18 November by KizmeRD

[JMB1943]

KizmeRD,

Thank you for that useful information!

Regards,

JMB

[KizmeRD]

First report from a lookout would, likely be of a ‘contact’ on the surface ‘’bearing red/green xxx” *** (relative to one’s own ship), subsequent reports (as the range closes) would then identify the type of vessel involved

MB

Edit - *** Actually, thinking about this some more,I believe that in the British Royal Navy during WW1, lookouts were still reporting relative bearings using the old system of ‘points’ (off the port/starboard bow, off the quarter, off the beam, off the stern). Since there were 32 points across 360 degrees, one point was equivalent of 11.25 degrees. For example an initial sighting report might be something like ‘smoke, sir, on the horizon, one point fwd of the port quarter’ - ‘… or two points abaft the starboard beam’ etc.

Edited 20 November by KizmeRD

[MikB]

What the plume looked like would matter. The Battle of Jutland began when a distant white plume was spotted by ships in the RN Grand Fleet's reccy screen. They deduced that it was a ship blowing off steam, for which one likely explanation was that it had been ordered to stop by a warship - which would have to be enemy. 

Only when they closed the scene did they spot nearby German torpedo boats.

There was already considerable intelligence that a HSF sortie was developing. A big network of information went into the process before optical range was reached.

[JMB1943]

KizmeRD & MikB,

Apologies for the late reply, but thank you both for the additional information.

I did not know about “the white plume” & the Battle of Jutland.

Regards,

JMB

[MikB]

1 hour ago, JMB1943 said:

KizmeRD & MikB,

Apologies for the late reply, but thank you both for the additional information.

I did not know about “the white plume” & the Battle of Jutland.

Regards,

JMB

I had it from  Marder's "From the Dreadnought to Scapa Flow", vol. III p. 56, and Massie's "Castles of Steel" p. 583.

Edited Monday at 19:21 by MikB