Three towers, one light

[island]

In the British Isles there is a light station of unique construction. It was constructed by one of the Stevensons in the mid-1800s. It has three inter-connected towers with only one lantern and light, with focal plane about 165 feet, and this light is on the shortest (48 -ft) tower. The other two towers were always without lanterns with lights.

[Fred]

An unusual one

Sounds like Sanda,nearly went there as a supernumary lightkeeper,but at the last moment somebody went sick at Pladda,so I did relieving duty there for a month instead.

[island]

You are correct, Fred. I don't think in the world of lighthouses there is another like Sanda. I note the character is long flashing white every 10 seconds. Does this mean the lamp is illuminated longer than 5 seconds?

http://www.nlb.org.uk/ourlights/history/sanda.htm
http://en.wikipedia.org/wiki/Image:Sandalighthouse.jpg
http://marinas.com/view/lighthouse/1544

[Fred]

In a 1992 book

LONG FLASHING,a flash of 2 or more seconds.regularly repeated.

Afraid I don't know Sanda's exact timing.

Since Sanda was automated in 1992,works in quite well?

[island]

Fred,

My curiosity about "long flash" is because that term is not used over here. A long flash would be described for example as a flashing light with a 2 second flash every 10 seconds or Fl. W. 10s (2s fl). If a 5 second flash each 10 seconds it would be an isophase light, if over on over 5 seconds it would be occulting. At one time there were lights with short-long uniform repeating flash but I don't know if there are any in use at present.

I also note in a some of the Sanda photos there is a rather large solar rack with numerous panels, more than I would have expected unless these panels are smaller than those I have seen at US lights. Or perhaps more because of less insolation at the more northern lattitudes or the light illuminated 24 hours.

David

[Fred]

David

Looks like "Long Flash" was only in use over here for a short period.

But US Coastguard light lists for 2007 mentions in
Abbreviations used in the Light Lists.

LFl-Long flash

but gives no further information

Solar panels
Might be that the solar panels at Sanda are old models,certainly new models are more efficient size for size.

Fred

[island]

Fred,

Chart No. 1-- Symbols Abbreviations and Terms (1990) identifies LFl as a light with a flash of 2 seconds or longer.

Using the pdf find function I searched all seven USCG light lists for LFl and found no light with a characteristic so designated. The LFl in Light Lists abbrrviation list appears to be a hold-over from years past.

The short-long flash I mentioned in earlier, thought apparently not used for lighthouses and lateral significant lighted buoys it is , however, the flash characteristic for the Mo(A) buoys, the Morse Code letter A (dot-dash). These are the "safe water" buoys positioned at the entrance to channels and/or harbors. I am sure you know this, Fred. I am posting this for others who may be interested in this topic. I do not know if there are Mo buoys displaying other Morse Code letters.

David

[Ross]

That has to be one of the coolest lighthouses ever... The tower construction is great!

[LeadingLight]

The Admiralty List of Lights still uses the term Long flash, as a regulary repeated flash of no less than 2 seconds. The fact that it is called a flash indicates that the light period is shorter than the dark. The same Admiralty List of Lights says Sanda LH has a flash of 0.3 seconds every 10 seconds, so that would mean it is not a long flash. The website of the Northern Lighthouse Board however mentions a long flash. So it's the seafarers "bible", the Admiralty List, against the owner of the light, the NLB.

The construction with the 3 towers is rare indeed. To me it looks like the two lower towers are just meant to get from the lower buildings on the site to the lighthouse without the risk to be blown or washed away by wind or gales.

[island]

Imagine being a keeper at Sanda in years past climbing the 210 steps with lamp fuel in hand to the lantern before sunset to light your kerosene lamp and then, "Oh darn, I forgot my matches!"

A 0.3 second flash seems very short for a lighthouse and more like a lighted buoy.

I have not seen the Admiralty Lists. The USCG Light Lists are on the internet. However, they are two years out-of-date. Many changes, some significant, have been implemented in the past two years. And the lists being on computer as also are the Weekly Notices to Mariners issued by each District that identify ATON changes it would seem to me that List of Lights could easily be maintained current.

[Fred]

When I was at Girdleness lighthouse with 182 steps,I was carrying a bucket of paraffin,reached about number 160 step and dropped it.

A frantic rush around for rags to mop up,up the stairs since I knew there were rags in the lightroom then down and catch it.

Then washing down to remove all traces.
Passed some of the watch away.

Seems we do things differently with flash lengths?

Maughold Head Lighthouse
FL (3) 30 sec
(fl 0.5,ec 2.0,fl 0.5,ec 2.0,fl 0.5,ec 24.5)

Point of Ayre Lighthouse
FL (4) W 20 seconds.
(fl 0.2,ec 2.3,fl 0.2,ec 2.3,fl 0.2,ec 2.3,fl 0.2,ec 12.3)

Point of Ayre (Low) usually known as "Winkie"
Character FL 3 sec......(fl 0.3 ec 2.7)

[island]

If you are looking for "Winkie', don't blink.

[LeadingLight]

Well, what do you do with these kind of questions? Ask someone who knows the answer. I mailed Bob McIntosh of the Northern Lighthouse Board about the different data in the ALL and on the NLB website and this is his reply:

I can only assume that the description on our website is a historical one as the older style lights would often have a long flash but with the modern electric light sources the length of the flash is mostly restricted to 0.3 seconds approximately. Therefore the official character at the moment would be 0.3 second flash every 10 seconds.

[Fred]

From Reeds Nautical Almanac 1973

Sanda Island Flash every 24 secs

General remarks Flash of 8 secs

Looks like somebody put two and two together and got five?

[LeadingLight]

Since it is 3 towers, 1 light, perhaps it may very well be possible that 2 + 2 = 5 .
But more seriously: perhaps in 1973 the light was still long flashing.