Macweter Pelagiac: a wolf in sheep's clothing or did they have their engine on?

I'm not technical and don't know how these hull speeds are worked out. Don't need to know really either:)

However, my Macwester Rowan 22 footer is rated at about 5 knots. This is a 2 ton boat, and last summer I was doing 6.4 knots for 3 hours when returning to Plymouth from Guernsey. Later on I got almost 7 knots on the trip from Mevagissey to Fowey and I was towing the inflatable!! And, no, I didn't have the engine running.

In light winds it would have been different!
 
There's a theoretical 'normal' top speed for a displacement hull which is dictated by the length of wave it creates. If it goes fast enough to create a wave longer than the LWL then it's trying to sail uphill at the bow.You can sort of see it here:

HGFLAGSHIP.jpg


If that boat were going any faster it would leave its quarter wave behind, the stern would drop and the boat would need to start climbing its own bow wave (maybe someone can find a better pic?) However, apply enough power through sails, engine, or wave acceleration and it will sail 'uphill' and exceed its hullspeed max. Certainly possible - imagine a small boat being towed by one of Her Majesty's frigates at full chat.
 
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I think the Pelagian has a similar hull to the Wight mkII and the Malin. The Pelagian will be heavier with two engines and have more drag with two props. Hard to be accurate with through the water speed given waves and tides etc, so rightly or wrongly I always compare and contrast with my gps speed 'over the ground'.

Can I believe a Pelagian could hit 7.5 knots under sail? Yes, there are times when we've had our Malin at 8/9 knots for short bursts before we've eased off. Three sails, a relatively narrow beam, and a bit of weight to cut through waves rather than bounce over them (as lighter yachts do) results in a bit of pace when the conditions are right.
 
Hmmmm.... very interesting, but not all what I was getting at!

Everyone knows (yes, even my mate Mick, who only sails once every other year) that maximum theoretical hull speed is determined by WLL. So, no surprise that, in the right conditions, the Pelagian will reach 7 knots or so.

What did surprise me, though, was her place in the PN listings, which are based on performance in races.

She is a fine choice for comfortable, reliable, steady passage making, but could she really beat an Arpege (et al) round the cans?
 
Aha, ok.......paradox resolved.

Reading further, the Byron PN's are based purely on calculations of length, weight, sail area etc. The formula used was derived by Terry 'stats man' Schnell, to give a rough guide only.

Whereas, based on my dinghy racing many years ago, I assumed the Byron numbers were, like the RYA numbers, based on real life racing performance.

Any volunteers to test the Byon numbers round the cans....a Scuttlebutt Pelagian V MG Spring 25 challenge, maybe?
 
Hmmmm.... very interesting, but not all what I was getting at!

Everyone knows (yes, even my mate Mick, who only sails once every other year) that maximum theoretical hull speed is determined by WLL. So, no surprise that, in the right conditions, the Pelagian will reach 7 knots or so.

What did surprise me, though, was her place in the PN listings, which are based on performance in races.

She is a fine choice for comfortable, reliable, steady passage making, but could she really beat an Arpege (et al) round the cans?

Round the cans will be very very difficult to beat boats like the Arpege, Sigma 292 and others. The Macwester Hulls are not greyhounds
and although they will reach and exceed their theoretical speed, they will not be agile enough and will loose a lot of ground on the tacks; horses for courses.
 
"Round the cans will be very very difficult"

Not least because you will struggle to actually find a Pelagian. I know of four: one in Scotland, two in Wales and one in the Netherlands. No doubt there will be more, but only a dozen or so were made.

Let me know if you ever make this happen!
 
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