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Old 29-06-2016, 23:58   #1
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Attenborough drogue research

I'm trying to find information about the Attenborough drogue for a research project I have going.

Before I follow-on, this thread is NOT to encourage debate about the pros and cons for the use of drogues, drogues vs para-anchors, or storm survival and tactics. I'm attempting to seek specific research data/info from CF members who may have an Attenborough drogue or who have used one in a past life. If you wish to respond I respectfully request that you stay on topic.

Here's what I know. The Attenborough drogue is fabricated from 100% stainless steel by Carisbrooke Marine Engineering (a UK company) in the 70's (I think). The company no longer exists so it is not possible to buy a "new" Attenborough drogue. I expect that the majority of these drogues would have been sold in the UK or Europe. I don't believe they were marketed in the U.S. There is only scant detail about this drogue in Victor Shane's DDDB and no case history of one being used in storm conditions.

Due to the relatively high cost of the stainless materials and the fabrication skills necessary to fabricate each individual unit, it is reasonable to assume that the drogues were only manufactured in small numbers and sold for a premium price. (I'm trying to confirm this). The manufacture of each of the four concave louver blades is quite complex.

Coppins of New Zealand sell a soft shell rip-stop material drogue marketed as the "Sea Claw". The diving design and performance of the Sea-Claw is similar to the Attenborough drogue. Both drogues are designed to "dive" and to perform their work 6-10 meters (dependent on rode length) below the turbulent storm waves above.

I have no data to indicate if the drogue performed well and just maybe it was a dud! It is quite a heavy unit (about 10kg) and doesn't store easily, so maybe not popular. I'm informed that the Attenborough design was based on sub-surface trawling equipment used by mine sweepers in WW2.

So was it a successful design??? Don't know!! It certainly is a substantial heavy weight unit with the promise of high performance. Hence the research project.

Once again, if any reader has additional details rigging a suitable rode, performance specifications, history about the manufacturer etc, and can contribute quality info that will assist me to better my research, I will be most interested and appreciative.
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Old 30-06-2016, 23:45   #2
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Re: Attenborough drogue research

Google "serial drogues" I was reading a research article on them not long ago. The one in the image above does not look too practical for use on a pleasure vessel nasty points, non folding, bulky etc.
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Old 01-07-2016, 00:10   #3
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Re: Attenborough drogue research

Never heard of them before, so I went for a quick look.

Found this:
https://books.google.com.pg/books?id...gue%22&f=false

info about sizing and rodes. You may need to scroll back a couple of pages to get to the start of the section.. There is an interesting picture of one rigged with two pendants for use as emergency steering!


Also one scant history in
Analysis & Lessons Learned: Drogues | Victor Shane's Drag Device Data Base

"In May 1990, the traditionally designed 35-ft. yacht Saecwen deployed an Attenborough drogue (louvered stainless steel design) while running before a storm in the Atlantic. The drogue seems to have slowed the yacht down too much. She began to be overwhelmed by the larger breaking seas. Saecwen was pooped three times in twenty minutes, whereupon her owner Charles Watson retrieved the drogue and ran under bare poles. Shortly thereafter the yacht was thrown onto her beam ends by a big sea, causing some damage. Watson thinks that a smaller drogue - one with less drag - might have been better, allowing slightly higher speeds. Unfortunately more information was not available. Saecwen's plight is described in the fourth edition of Heavy Weather Sailing and does seem to fall into consistency with the Abernethy bounding box - "below 6-7 knots, but above 3 knots.""
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Old 07-07-2016, 00:45   #4
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Re: Attenborough drogue research

Thanks to the two responders. My special thanks to StuM for his research and for providing the link to the Earl Hinz's book "Heavy Weather Tactics". The link was most appreciated and provided valuable additional information that I'd not seen before.


The link confirmed that the drogue is a practical design for the the long distance cruisers. Hinz identified that it is practical option to mount the drogue externally on the pushpit (to aid easy deployment in storm conditions), that the side wings ensure that it tows/steers straight without rotation, and that the stainless steel design can survive multiple deployments. Most interestingly I'm now aware that the drogue was fabricated in three sizes.


I'd still like to hear from other CF members who may have design, sales, test or rigging information on the Attenborough drogue.
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Old 31-07-2016, 01:57   #5
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Attenborough drogue research - update

Basis of Attenborough design.
CF members may be interested in the additional information about this drogue.

The drawing shows rigging setup for the "kite" used by the Royal Navy (U.K.) which was included as part of the tackle used for mine sweeping. This design was basis for the Attenborough drogue design. The drogue is intended to "fly" vertically similar to the wings of the Focker Triplane.

Re Focker Triplane photo:
From the photo, you can see that the trailing edge of the wings of the aircraft turn down to promote lift where as the trailing edge of each of the four louvers of the Attenborough drogue roll up to promote the dive action.

The suggested length of the rode is relative short (50-60 meters) compared to the suggested rode length for other drogues. When correctly rigged and deployed, the drogue is designed to dive and hold station some 5-8 meters below the turbulent storm waves above.

I'm still not sure if all this works in practice. I look forward to posting some actual test results in the near future.

Hope you find this interesting. Rgds
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Old 31-07-2016, 02:56   #6
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Re: Attenborough drogue research

Interesting stuff. Keen to see how your tests turn out. Thanks

Sent from my SM-G930F using Cruisers Sailing Forum mobile app
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Old 31-07-2016, 03:30   #7
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Re: Attenborough drogue research

Seems that Nigel Richard Attenborough only gained one patent. His patent application was GB1989/000446.

British patents are not the most accessible in the world. It's easier to access US patents or 'world' patents.

Attenborough seems not to have sought a US patent. The US patent database directs inquiry to the world patent, which is available from the European database.


Attached is the world patent, WO1989010295A1.pdf (about 560 KB).



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Old 31-07-2016, 03:49   #8
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Re: Attenborough drogue research

Note the ultimate para on p. 5.

That para is typed by a typewriter or font ball (a sans serif typeface) different from the machine or font ball (serif typeface) that did the rest of the document.


That suggests the para was added as an afterthought specifically to protect the up curve/up tilt of the vanes.


The upward curve and tilt are shown in the drawings.
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Old 31-07-2016, 04:40   #9
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Re: Attenborough drogue research

The text of the British patent, GB2218956, is identical - including that paragraph in sans serif typeface.

Just for the complete set: GB2218956A.pdf, about 440 KB.
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Old 31-07-2016, 04:59   #10
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Re: Attenborough drogue research

The UK electoral roll of 2002 had Neil Attenborough and his spouse Jennifer (they married in 1982, not that we're prying) living at that address (Puttenham Hill, Guildford, GU3 1AH - Residents, Businesses, Information - 192.com suggests that Fallowfield has not changed hands for a while).

One real estate website suggests that Fallowfield would be worth GBP1 mill + on the market.


I've not found NA's telephone number. A CF member in Guildford or Surrey should be able to find it for you (if they still produce dead tree versions of phone books).
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