Drogue or Parachute anchor?

[tome]

Re: Parachute anchor depl;oyment theory?

I reckon I'd go with a bridle onto my primary winches with a turn round the aft cleats and a lot of chafe protection where it goes through the fairleads. Come to think of it, it would probably jump the fairleads so chafe protection where it goes over the stern.

Windage isn't too bad with sprayhood down

 

[iangrant]

Re: Parachute anchor depl;oyment theory?

I'm with you on the rope in that I'm hopeless in guessing the size - all I know is it is bloody heavy.

Ian

 

[boatmike]

Re: Parachute anchor depl;oyment theory?

Sounds good. Can you not fix a couple of closed fairleads on the transom? The bridle will jump out of open fairleads if you are not careful. Its important to ensure your warp does not sweep across the cockpit and wipe the aft stay away if the boat broaches ........

 

[boatmike]

Re: Parachute anchor depl;oyment theory?

Probably all right then!

 

[tome]

Re: Parachute anchor depl;oyment theory?

Good idea, I'll look at replacing the open fairleads when I'm next down at the boat. I'll also check the under-deck fixings to see if they need any additional reinforcement. I hadn't considered the backstay in a broach so thanks for that.

 

[iangrant]

Re: Parachute anchor depl;oyment theory?

It's not just the backstay thinking about it it's all them rails and things sticking up - let alone me wind vane steering. Might have to look a a para anchor out the front!

Ian

 

[boatmike]

Re: Parachute anchor depl;oyment theory?

Noooooo! Just make up a bridle with a coupla closed fairleads! works better that way anyway cos when the boat comes around the taught side will pull it straight again by pulling on t'other side... It's a doddle.... 'Course like lots of other things it works better on a cat with 2 backstays and a bridle inside them......

 

[BlueSkyNick]

Re: Parachute anchor depl;oyment theory?

[ QUOTE ]


It will take a couple of hefty crew to sort out letting it go over the stern, .....

Ian

[/ QUOTE ]

That's tome out of the equation then! Hope you're gonna have a couple of other real men on board. /forums/images/graemlins/smile.gif

 

[tome]

Re: Parachute anchor depl;oyment theory?

Who rattled your cage, dungbeetle?

 

[iangrant]

Re: Parachute anchor depl;oyment theory?

You need to be careful - he's just stiched together a real heavyweight hand bag to clout you with..

Ian

 

[tome]

Re: Parachute anchor depl;oyment theory?

Boatmike

Take a look at this article about series drogue attachment, looks like a better idea than a closed fairlead.

 

[ChrisE]

Re: Parachute anchor depl;oyment theory?

As luck would have it I, too, have been doing the sums regarding multiplait strengths for making the bridle for our series drogue. Tome, your link was very useful, the notes from Donald Jordan regarding how to attach and the loads imposed in the worst case were extremely illuminating. It looks like for my 20,000lbs displacement I need 20mm multiplait which, according to Marlow Braids, has a BS of 9890lbs which is close enough to the theoretical 10,000lbs load for a breaking wave landing on a quarter.

FWIW, I've never used the series drogue but I have used warps to keep the speed down in a big following sea. The effect of holding the bum into the sea enabling the autopilot or windvane to work effectively have to be seen to be appreciated.

 

[tome]

Re: Parachute anchor depl;oyment theory?

Yes, I found it useful also. Our displacement is about the same so reckon we need 116 cones on 20mm. Be careful to use nylon/nylon multiplait to give it the stretch, ordinary multiplait is frequently polyester or polyester/nylon. I'm tempted to order the kit from Donald Jordan.

Like yourself, I've trailed warps in a big sea but the series drogue appeals as a well-thought out solution. I can get the SS quarter plates made up locally, guess thy will also form a good towing bridle.

 

[iangrant]

Re: Parachute anchor depl;oyment theory?

Wot about that 43 footer then, you'll need bigger for that!

Ian

 

[tome]

Re: Parachute anchor depl;oyment theory?

Yes, good point. Displacement would be abt 30,000lbs so I'll need to add another 16 cones and lengthen to 300 feet. Ta!

 

[BlueSkyNick]

Re: Parachute anchor depl;oyment theory?

Pardon me for asking, but where are you getting the number of cones from? I can't find it in the thread or Donald whassisname's paper - or have I overlooked it?

 

[tome]

Re: Parachute anchor depl;oyment theory?

Well porky, you have to look up the displacement of your boat. If, say, it was a Moody 346 of 11,200 lbs displacement then you'd need 100 cones for the boat and another 7 to make up for your additional weight on 258 ft 16mm braid.

Make sure you have someone with a bit more initiative than yourself when it comes to deployment time.

 

[BlueSkyNick]

Re: Parachute anchor depl;oyment theory?

Listen dopey, I already knew the displacement of the boat, fully laden with myself and others. But I dunno where to find how many cones and feet of rope are required per displacement.

Just cos you are still sulking that you weren't allowed out to play last weekend and I was, shouldn't stop you helping all the others others on this esrtwhile forum who would like to know the answer.

 

[Peppermint]

Re: We should try talking to the RNLI

They have some experience with drogues.

I sat on the rail of a racing boat one murkey night. The bloke next to me told me a tale about his brother who, having towed warps to slow him up, decided that adding a couple of tyres he carried as fenders to the bight might help. All went well and the additional drag was tangible. That is until the whole lot went phertang!!!!! and the tyres shot back onboard. It appears that you really need to get the warp length right.

 

[tome]

Re: Parachute anchor depl;oyment theory?

Yes, still a bit tetchy about last weekend especially since my hard earned brownie points went straight out the front door I'd left wide open with my keys in the lock.

Anyway, have a look here.