What is hiding inside Your Rudder? Potential Problems: Corrosion Bad workmanship Faulty design Inferior materials

Transcription

1 What is hiding inside Your Rudder? Potential Problems: Corrosion Bad workmanship Faulty design Inferior materials

2 OSR a) Except when the principal method of steering is by means of an unbreakable metal tiller, an emergency tiller capable of being fitted to the rudder stock

3 OSR b) Crews must be aware of alternative methods of steering the yacht in any sea condition in the event of rudder loss At least one method must have been proven to work on board the yacht An inspector may require that this method be demonstrated

4 INTERPRETATION No 1/ Emergency Rudders Does OSR 4.15 Emergency Steering require an emergency rudder? Answer: Not necessarily. The emphasis in (b) is for an effective alternative method of steering to be devised and tested by the yacht so that a method is developed which is most suitable for each particular yacht and crew.

5 Steering System As important as hull integrity, standing rigging and mast! Know it, Service it, Respect it

6 Know It 1. Designated expert and back ups with extensive knowledge of steering system 2. Don t trust a factory or after market installation Carefully inspect it

7 Know It 3. Be familiar with primary steering gear, control cables (or gear system), linkages, and pulleys or sheaves 4. Ensure emergency tiller for rudder actually works & location is on safety equipment chart Tight fit (no play) Try it under load

8 Service It 1. Service and inspect all components prior to the race No worn or fatigued parts Consider dropping rudder to inspect at lower bearing just above rudder (industrial radiography?) Upper and lower bearings not worn Lubrication If rudder condition in doubt may be cheaper to replace than risk losing it on the high seas

9 Service It 2. Plan for spares (e.g.; cable/kevlar line, linkages) Take required tools Location on Safety Equipment Chart

10 3. Before race Service It At crew meetings discuss scenarios if rudder is lost Reinforce role of Person in Charge and rest of crew in case of incident Practice inspections in high seas 4. Regular inspection while racing

11 Respect It 1. Good seamanship Sail balance 2. It s a long way don t overstress the rudder

12 Design Considerations for Emergency Rudder 1. Type of failure of primary rudder (clean break or bent rudder stock) 2. Ease of steering - it has to work 3. Anticipate going a long distance & high sea state 4. Must work with storm jib and trysail 5. Attachment method to the hull--how will you install the rudder while at sea 6. Stowage safe storage of emergency rudder when you're (hopefully) not using it 7. Know the forces 8. Blade size (underwater surface area)

13 Force on the Blade F = A * Cl * 1/2 * RHO * V^2 F = force (lb) A = area below transom (ft^2) Cl = Coeff. of lift (use 3.0 to allow for pumping transients) RHO = density of water ( slugs/ft^3) V = design speed (ft/sec) (1 knot = ft/sec) F = 8.5 * A * V^2 F = force (lb) A = area below transom (ft^2) V = design speed (knots) Example: 1 ft. x 4 ft. blade, 7 knots: F = 1,666 lb

14 Cautions 1. Saving money in the design and construction could be expensive One off systems increase risks of failure 2. Needs to be robust and durable 3. Don t leave home without your emergency rudder!

15 SOS Rudder from Scanmar The SOS Rudder is an emergency steering system designed to get you to the nearest port in case of rudder failure. DO NOT ATTEMPT TO CONTINUE TO RACE, OR TO CARRY A HEAVY PRESS OF SAIL Hans Bernwall: Spade rudders are efficient & strong but more vulnerable than skeg Over 100 units sold; no failures $200 price reduction for Vic Maui skippers

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17 Two Sizes of SOS Rudder

18 Three Steering Configurations

19 Installation

20 SOS Rudder

21 Beneteau 42

22 Hughes-Perry 63 tri

23 Three Point Framework to Hold Pintles and Gudgeons

24 Three Point Framework to Hold Pintles and Gudgeons

25 Rudder in a Cassette System

26 Rudder for Cassette

27 Rudder in Cassette

28 Hydrovane

29 Some Thoughts Mission changes, no longer racing Windvane may work but may be too small if main rudder is lost Spinnaker pole definite no no 2' X 4' X 3/4" ply clamped U-bolts. Pole lashed vertically over transom to stern cleats, supported from dropping by rolling hitches to pushpit rail. Line on either side, clove hitched around pole, below water level, and led to winches

30 A few Rudder losses in Vic Maui Ajax, Rocket J Squirrel, and Foxfire (1992) Something Wicked (2008)

31 It Can Happen Something Wicked, Beneteau 40.7

32 Victoria before race We Were Something Wicked!

33 Clean Break

34 Design Flaw

35 Recovery

36 Steer to Starboard

37 Steer to Port

38 Spinnaker Pole Lashed to Pushpit

39 Lessons Learned 1. Don t underestimate the forces 2. Emergency rudder may work in calm seas and light winds Test it under high seas and strong winds 3. Plan how you will install it -- who will do what AND practice at sea 4. Assume it ll happen in the worst conditions 5. If it happens stay calm 6. You can make it home safely on your own 7. Crew experience, passport numbers, and safety equipment written on a sheet in navigation table 8. Take a drogue appropriately sized 9. Use a spinnaker net

40 Kinetic s Emergency Steering Drogue Manufacturer: Jim Buoy Model: 926 (18 diameter)

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42 The Message 1. Meticulously check your rudder 2. Plan to be self sufficient 3. Assign roles, train, and discuss scenarios 4. Don t delay in solving your emergency steering challenge When Needed it Better Work Must steer boat with or without wind, whether or not yacht s rudder is still in place Test under high seas and wind before race

43 Swiftsure International Yacht Race, May 24 26, 2014 Vern Burkhardt, Chair