440: Lagoon 440 Performance ?

[impi]

Originally Posted by D&D

Nope...no help here. sorry. Fixed blades on CatNirvana...not overly concerned with speed -- She sails along very nicely as it is, as you would know -- but very concerned with minimal maintenance and KISS. Lotsa difficult experiences from racing days with folding props on OPB (Other People's Boats).

Yes, the maintenance thing makes a lot of sense. I am looking at it more from a perspective of getting the motors off in lighter winds. Racing is also not our thing - the 440 is plenty fast enough for us as cruisers but I am always looking to get the engine off in lighter winds and wonder if having less drag on the prop will get us there.

[Kaptain Ken]

We have the Max Props on our 440 and have been pleased. Every once in a while they will "stick" in the open position, but a quick burst of speed or a few changes from forward to reverse and back free's them up.

[impi]

Originally Posted by Kaptain Ken

We have the Max Props on our 440 and have been pleased. Every once in a while they will "stick" in the open position, but a quick burst of speed or a few changes from forward to reverse and back free's them up.

Kaptain Ken - would you say these props get your 440 going quicker in lighter conditions?

[Kaptain Ken]

I believe it does, but having had the Max Prop's on from the beginning I have nothing to compare it to. I do know this, my partner in the boat originally wanted to pursue the electric drive Lagoon 420 and I went up to Annapolis for a Catamaran Company comparison sail of the 420 and 440. The idea behind the hybrid 420 was to utilize battery power (with backup generator, if needed) to get away from the dock and get the sails up and turn off the electric motors - then, after the boat reached a certain speed (I beleive it was somewhere between 5 and 6 knots thru the water), a "clutch", which had allowed the props to freewheel up to that point, would disengage and turn the electric engines into generators to re-charge the batteries. Long story short, the boat sailed like a dog because of the huge drag of the oversized props needed to turn the motor/generators to generate sufficient power. I asked others who were checking out both concepts that day to e-mail my boat partner with their comments and all of them agreed with my analysis. We chose the 440 and have never regretted the decision.

On the negative side, folding props are not cheap. On a catamaran, the price doubles!!!

[D&D]

Originally Posted by impi

Yes, the maintenance thing makes a lot of sense. I am looking at it more from a perspective of getting the motors off in lighter winds. Racing is also not our thing - the 440 is plenty fast enough for us as cruisers but I am always looking to get the engine off in lighter winds and wonder if having less drag on the prop will get us there.

Light winds are fairly common around here too...and the key element for us (between silence and an engine 'on') is whether we're in a hurry or not. If not, then we can usually squeeze 3-4knSOG out of her even in the light stuff...and sit back, relax and enjoy a very quiet and smooth ride! If we need to be somewhere within a certain time, however, then it's one engine on. No doubt you're the same though...so nothing new here for you.

We wish you well with the folding props.

[2Wind]

I fitted Autostream 3 blade feathering SS props several years ago.
http://www.seahawk.com.au/images/Autostream_2010.pdf

They are such a thing of beauty when new you want them on display!

Previously I just had the standard Yanmar 2 blade fixed.

Advantages:
1. Excellent cavitation free reverse thrust
2. Easy pitch optimization for achieving ideal RPM/load/fuel efficiency - easy to do in water
3. Minimal maintenance: anodes easily changed in water and can be greased in water yearly
4. Trouble free so far
5. + 0.5 - 1.0 kt under sail being greatest in the 4.5-6 kt SOG range ( above 8kts, I'm sure its the other underwater extensions that slow you down)

As to whether they result in me using the engine less, I'd have to say that being time poor, I generally resort to an engine if on a passage when my SOG falls below 4.5kts and there is little prospect of more wind arriving soon. I have somewhat over pitched my props so that at 1600-1700rpm on one engine, I'm generally doing 5.5 to 6 kts depending on sea state. If I have all the time I can drift around with the best of them! I would have to say that from a comfort perspective that the poorest quality of my 440 is sailing in a dying breeze with the residual sea on the beam at which time the short and sharp movements of the cat when un-dampened by the loaded sail become uncomfortable. It is especially then that I put on a motor and motor sail.

[impi]

Useful information on folding props there. Our fixed 2 blade props are 17x17 which according to the Yanmar boys is quite steep. We have no issue with how well they push us through the water - our issue is wether they are slowing us down much in lighter air and if changing this will save engine time. I guess the cost verses saved engine hours is what I need to look into. Thanks!

[2Wind]

Speaking of (light wind) performance......





See my thread....

http://www.cruisersforum.com/forums/...ds-142475.html

[2Wind]

Here are some heavier weather numbers:

Friday 11th September.
Tangalooma to Wide Bay Bar
Theoretic sortest route distance -84 NM
Actual distance covered - 96NM
Wind 15-32kts Southerly- predominantly in the 18-25kt range
Seas - 2m SE swell, 1-1.5m S sea
Course essentially dead down wind necessitating down wind tacking at 150 and 210 degrees
Time: 12 hrs
Average speed: 8.0kts
Max Speed: 19.5kts surfing
Main: 1 reef
Genoa: Full wind 23-28kts, 70% when above 28kts.
Screecher: Wind under 23kts
What a ride, especially when the wind reached 30kts with some squalls!
Look for the dark line of cloud in photo #2.







I enjoyed the "rooster tail" when surfing.
Didn't enjoy the failed first reefing line (after 11 hours - chafed at boom end sheave) nor the failled screecher halyard (chafed on unrecognized cracked mast head sheave). Managed to pull the sail back on board before she tore. Both repaired once in calm water inside the Sandy Straits.

[D&D]

Originally Posted by 2Wind

Here are some heavier weather numbers:

Friday 11th September.
Tangalooma to Wide Bay Bar
Theoretic sortest route distance -84 NM
Actual distance covered - 96NM
Wind 15-32kts Southerly- predominantly in the 18-25kt range
Seas - 2m SE swell, 1-1.5m S sea
Course essentially dead down wind necessitating down wind tacking at 150 and 210 degrees
Time: 12 hrs
Average speed: 8.0kts
Max Speed: 19.5kts surfing
Main: 1 reef
Genoa: Full wind 23-28kts, 70% when above 28kts.
Screecher: Wind under 23kts
What a ride, especially when the wind reached 30kts with some squalls!
Look for the dark line of cloud in photo #2.

Attachment 109005

Attachment 109006

Attachment 109007

I enjoyed the "rooster tail" when surfing.
Didn't enjoy the failed first reefing line (after 11 hours - chafed at boom end sheave) nor the failled screecher halyard (chafed on unrecognized cracked mast head sheave). Managed to pull the sail back on board before she tore. Both repaired once in calm water inside the Sandy Straits.

Woo Hoo! Sounds like a great ride indeed!!

[impi]

Originally Posted by 2Wind

Here are some heavier weather numbers:

Friday 11th September.
Tangalooma to Wide Bay Bar
Theoretic sortest route distance -84 NM
Actual distance covered - 96NM
Wind 15-32kts Southerly- predominantly in the 18-25kt range
Seas - 2m SE swell, 1-1.5m S sea
Course essentially dead down wind necessitating down wind tacking at 150 and 210 degrees
Time: 12 hrs
Average speed: 8.0kts
Max Speed: 19.5kts surfing
Main: 1 reef
Genoa: Full wind 23-28kts, 70% when above 28kts.
Screecher: Wind under 23kts
What a ride, especially when the wind reached 30kts with some squalls!
Look for the dark line of cloud in photo #2.

Attachment 109005

Attachment 109006

Attachment 109007

I enjoyed the "rooster tail" when surfing.
Didn't enjoy the failed first reefing line (after 11 hours - chafed at boom end sheave) nor the failled screecher halyard (chafed on unrecognized cracked mast head sheave). Managed to pull the sail back on board before she tore. Both repaired once in calm water inside the Sandy Straits.

AWESOME SAILING - Well done

[Wellington]

16 1/2 days from Galápagos (Isabella) to Marquesas (Nuku Hiva)
- without spinnaker nor gennaker, just the standard 43m2 genoa
- with one reef at night and most days
- without folding props, just the standard, fixed 2-blade props
- overloaded with 1.7 tons of fresh water, 1100 liters in the tanks + jerrycans, 600 liters drinking water in 5-liter bottles (to reassure my wife...)

[2Wind]

Originally Posted by Wellington

16 1/2 days from Galápagos (Isabella) to Marquesas (Nuku Hiva)
- without spinnaker nor gennaker, just the standard 43m2 genoa
- with one reef at night and most days
- without folding props, just the standard, fixed 2-blade props
- overloaded with 1.7 tons of fresh water, 1100 liters in the tanks + jerrycans, 600 liters drinking water in 5-liter bottles (to reassure my wife...)

Whoaaa.

That's like 16 consecutive 180NM days.....

Might be a record!

[impi]

Originally Posted by Wellington

16 1/2 days from Galápagos (Isabella) to Marquesas (Nuku Hiva)
- without spinnaker nor gennaker, just the standard 43m2 genoa
- with one reef at night and most days
- without folding props, just the standard, fixed 2-blade props
- overloaded with 1.7 tons of fresh water, 1100 liters in the tanks + jerrycans, 600 liters drinking water in 5-liter bottles (to reassure my wife...)

That is great performance ...

[D&D]

Originally Posted by impi

That is great performance ...

+2