Search found 30 matches

by fishwics
Sat Aug 28, 2021 4:10 pm
Forum: Craft
Topic: Forward facing rowing
Replies: 0
Views: 17871

Forward facing rowing

For those who want to know how/if forward facing rowing systems work, a friend of mine has fitted one to his new boat. There is a Youtube video here: https://www.youtube.com/watch?v=NywPV4lVaw4
by fishwics
Sat Jul 10, 2021 8:45 pm
Forum: Hulls & Keels
Topic: Historical examples of one-way outrigger boats
Replies: 1
Views: 53034

Re: Historical examples of one-way outrigger boats

Attached picture is from Hornell "Water Transport", pub: Cambridge, 1946, reprinted David & Charles, Newton Abbot, 1970.
The text in the body is almost identical to that you quoted and offers no new insight.

Simon
Hornell Plate XL.jpg
(56.68 KiB) Not downloaded yet
Hornell Plate XL.jpg
(56.68 KiB) Not downloaded yet
by fishwics
Fri Oct 23, 2020 3:48 pm
Forum: Welcome to the AYRS Forums
Topic: Attachments
Replies: 2
Views: 9969

Re: Attachments

I don't allow upload of files containing macros, so .xlsm is not allowable. .xlsx should be allowable if I have the board settings correct. I think the Administrators can override that setting, as a special case, if you have something with macros in that you really must have uploaded. In which case ...
by fishwics
Wed Apr 29, 2020 5:32 pm
Forum: Craft
Topic: Halyard locks and reefing hooks
Replies: 8
Views: 16098

Re: Halyard locks and reefing hooks

That's a nice system - and presumably it works with reefed sails by adding another (or more) fixed pin at the appropriate position on the mast.

Did you devise it, or is it a commercial system?

Cheers
Simon
by fishwics
Fri Dec 06, 2019 2:31 pm
Forum: Craft
Topic: Hydrofoiling Europe-Dinghy
Replies: 0
Views: 10302

Hydrofoiling Europe-Dinghy

Hydrofoiling Europe-Dinghy by Urde, Jesper and Karlsson, Simon An interesting paper by two students at Lund University, Sweden. Includes details of the foils used. Simon Hydrofoiling_Europe_Dinghy.jpg Abstract The aim of this master thesis was to develop and build a prototype of separate hydrofoils ...
by fishwics
Fri Jun 14, 2019 8:26 pm
Forum: Craft
Topic: Chapman Sands SC threatened with closure
Replies: 0
Views: 10942

Chapman Sands SC threatened with closure

Chapman Sands SC, which probably did more than most in the UK to promote the development of modern multihulls, is threatened with closure as the local council have apparently decided to tax it as a profit-making business instead of a not-for-profit club. Please consider signing the petition to get t...
by fishwics
Sat Mar 09, 2019 8:09 pm
Forum: Events & other announcements
Topic: Commercial Sail Type approval
Replies: 2
Views: 9241

Re: Commercial Sail Type approval

https://www.maritimejournal.com/news101 ... rcial-sail is still working

(it needed the https)
Simon
by fishwics
Mon Jan 21, 2019 11:41 am
Forum: Craft
Topic: Foiling Sailboards "porpoising"
Replies: 0
Views: 10649

Foiling Sailboards "porpoising"

At the AYRS meeting yesterday, Mark Tingley raised the topic of foiling sailboards "porpoising" that he'd observed at Speedweek. Essentially they build up a pitch oscillation that usually ends with the front of the board hitting the water, and the board crashing. He suggested that this may be due to...
by fishwics
Mon Dec 03, 2018 5:45 pm
Forum: Craft
Topic: Ngalwa Sailing in Tanzania
Replies: 1
Views: 7136

Re: Ngalawa Sailing in Tanzania

Things may have changed since I was down on the coast (well, it was 50 years ago!), but memory says they were double outriggers, and memory also says there was no organisation as such that allowed you to book one, you had to negotiate with a fisherman to take you out (and there were a number of them...
by fishwics
Fri Nov 30, 2018 4:17 pm
Forum: Sails & Aerodynamics
Topic: UK Sailmakers J109 Class 'Fluid Structure Interaction' Test Report
Replies: 0
Views: 10664

UK Sailmakers J109 Class 'Fluid Structure Interaction' Test Report

I found this to be a fascinating bit of reading Simon QUOTE In Grand Prix classes throughout the sport of sailing, it is well known that sheeting angles are becoming tighter and tighter – modern TP52s have jib sheeting angles as close as 4 degrees off the centreline. The J109 class in Ireland is a g...
by fishwics
Tue Nov 27, 2018 7:06 pm
Forum: Events & other announcements
Topic: Call for papers: Power and Propulsion Alternatives for Ships
Replies: 0
Views: 10601

Call for papers: Power and Propulsion Alternatives for Ships

Royal Institution of Naval Architects Power and Propulsion Alternatives for Ships 23 January 2019, London, UK Call for Papers Shipping is vital to the world economy. It is a critical part of international import and export markets and supports the global distribution of goods. As for all industries...
by fishwics
Sat Nov 24, 2018 8:36 am
Forum: Events & other announcements
Topic: New RINA eNewsletter App launched
Replies: 0
Views: 11256

New RINA eNewsletter App launched

http://news.rina-mail.org.uk/Yogip/RINA_V5/2/Images/HTMLEditor/EHID-1249/eed2f7f878b749c19abe03d4445d6f39.gif New eNewsletter App launched The Naval Architect eNews Shiprepair & Maintenance eNews Ship & Boat International eNews Warship Technology eNews Offshore Marine Technology eNews The Instituti...
by fishwics
Mon Aug 20, 2018 9:54 am
Forum: Sails & Aerodynamics
Topic: WIND TUNNEL MEASUREMENTS OF THE PERFORMANCE OF CANOE SAILS FROM OCEANIA
Replies: 0
Views: 11019

WIND TUNNEL MEASUREMENTS OF THE PERFORMANCE OF CANOE SAILS FROM OCEANIA

I've been sent a copy of this paper http://www.jps.auckland.ac.nz/docs/Volume123/JPS_123_1_01.pdf by ANNE DI PIAZZA (Aix-Marseille Université, Centre National de la Recherche Scientifique), ERIK PEARTHREE and FRANÇOIS PAILLÉ (Ecole Nationale Supérieure de Mécanique et d’Aérotechnique) published orig...
by fishwics
Sun May 06, 2018 7:26 pm
Forum: Hulls & Keels
Topic: Component Waveform Theory
Replies: 1
Views: 8288

Re: Component Waveform Theory

I found that article very interesting. The full paper, by Australian Alan Skinner, is at http://www.mcgowanmarinedesign.com/Home_files/Hull%20Speed_%202017.pdf It's quite a long paper (160pp), and doesn't print well. The first part is a review of the history of "rule of thumb" hull design methods, b...
by fishwics
Fri Mar 16, 2018 9:34 pm
Forum: Events & other announcements
Topic: Jan/Feb Newsletter 2018
Replies: 2
Views: 8890

Re: Jan/Feb Newsletter 2018

Ask, and in your case it shall be given as you are a paid-up member.

(One of these days I shall make it automatic, but at present validating you as a paid-up member is a manual process)
by fishwics
Fri Nov 10, 2017 3:50 pm
Forum: Craft
Topic: Flettner rotor ship
Replies: 5
Views: 17185

Re: Flettner rotor ship

As far as I can tell from the press release, they're for propulsion, and, although nothing says so, they could be useful for close quarter manoeuvring given that there is one at each corner of the ship. I'm not quite sure how you generate electricity from a rotor - they are not self-spinning, but ha...
by fishwics
Fri Sep 22, 2017 12:15 pm
Forum: Events & other announcements
Topic: Composites Optimization of a Foiling C-Class Catamaran
Replies: 0
Views: 12125

Composites Optimization of a Foiling C-Class Catamaran

Some of you might be interested in this webinar. Composites World is one of those free industry magazines they send to anyone who says they are in the industry (since advertising revenue depends on circulation numbers). The information is technically oriented, but usually pretty accessible to the am...
by fishwics
Tue Sep 19, 2017 12:34 pm
Forum: Craft
Topic: MicroTransat
Replies: 21
Views: 46108

Re: MicroTransat

See also announcement of RIN meeting on autonomous boats here http://www.ayrs.org/phpbb/viewtopic.php ... 2496#p2666
by fishwics
Tue Sep 19, 2017 12:31 pm
Forum: Events & other announcements
Topic: Royal Institute of Navigation Meetings
Replies: 1
Views: 8158

Royal Institute of Navigation Meetings

http://www.rin.org.uk/images/logo_shadow.jpg The following RIN SCG events, taking place in October and November, may be of interest: 4 OCTOBER WEDNESDAY1800 The Cruising Association, CA House, 1 Northey St, London E14 8BT AUTONOMOUS VESSELS – A REAL REVOLUTION Prof. Andy Norris FRIN The second in a...
by fishwics
Sat Jul 08, 2017 11:13 am
Forum: Events & other announcements
Topic: Eyemouth International Sailing Craft Association is selling its collection
Replies: 0
Views: 12376

Eyemouth International Sailing Craft Association is selling its collection

ONLINE AUCTION (Eyemouth, Cardiff & Lowestoft) Closing 12 Noon Wed 26th July 2017 * Being sold under the instructions of the liquidators of Eyemouth International Sailing Craft Association Limited (Eisca), a Scottish registered Charity MARITIME MUSEUM’S BOAT COLLECTION – Comprising: 270 Boats of Int...
by fishwics
Sun Apr 23, 2017 11:33 am
Forum: Sails & Aerodynamics
Topic: Flow round a wing
Replies: 1
Views: 8270

Flow round a wing

Nice video from Cambridge Univ.
https://youtu.be/UqBmdZ-BNig
by fishwics
Wed Mar 22, 2017 9:55 pm
Forum: Members Sales and Wants
Topic: C-class Emma Hamilton for sale on EBay
Replies: 1
Views: 8057

Re: C-class Emma Hamilton for sale on EBay

Memory says once-upon-a-time she belonged to AYRS? or was that merely mooted but not carried through?
by fishwics
Sat Jan 28, 2017 6:59 pm
Forum: Hulls & Keels
Topic: Transonic hull
Replies: 7
Views: 17594

Re: Transonic hull

Can, to some extent and for a limited range of speed, also be done with a single hull: http://www.duckworksmagazine.com/04/s/e ... /index.cfm
See also Catalyst No 11 page 9 http://www.ayrs.org/catalyst/Catalyst_N ... pdf#page=9 et seq
by fishwics
Thu Jan 26, 2017 9:04 pm
Forum: Hulls & Keels
Topic: Transonic hull
Replies: 7
Views: 17594

Re: Transonic hull

Caveat - I've never seen one of these hulls in action ... BUT I have doubts that any single hull will operate without making waves*. I suspect that if you work out the curve of cross-sectional areas, and built another hull with the same curve it would have the same wave making characteristics -- or ...
by fishwics
Sun Jan 15, 2017 9:54 pm
Forum: Members Sales and Wants
Topic: Wanted Drawings of Manners Trifoil
Replies: 1
Views: 8236

Re: Wanted Drawings of Manners Trifoil

Eric Manners did indeed die some years ago, and most of his archives were destroyed after his death. I'll see if I can dig out a contact, but don't hold out much hope.
Simon
by fishwics
Sun Dec 25, 2016 10:41 pm
Forum: Craft
Topic: Trailers, a warning
Replies: 2
Views: 10847

Re: Trailers, a warning

For those who cannot (or don't want to) handle MSWord documents: Fredthecharlie wrote: A WARNING When checking your boat trailer don’t forget to look under the suspension units especially if they are mounted in a channel section; you might miss seeing something like this! It had been unused for seve...
by fishwics
Mon Nov 14, 2016 11:09 pm
Forum: Craft
Topic: Kite surfing
Replies: 1
Views: 9143

Re: Kite surfing

There seems to be a difference between that part of the kite surfing world which is part of World Sailing and that part which is not (International Kite Sports Federation). IKSF don't want anything to do with World Sailing (formerly ISAF). The other problem is that if Kite Sailing becomes an Olympic...
by fishwics
Wed Nov 09, 2016 10:43 am
Forum: Welcome to the AYRS Forums
Topic: Fishwics Brief Bio
Replies: 2
Views: 11746

Fishwics Brief Bio

1. Been sailing for a long time (50+ years) - mainly dinghies and other small boats 2. Helped develop RIBs before they became commercial 3. Have messed around with sailng canoes and proas, mainly of my own design 4. Professionally I am a retired electronic engineer, and now help run a sailing school...