Running Angle

Can any other 43 or 46 owners provide what their cruise running angle is? I put a digital level on the map table static and at 24 kts cruise. I get a 6 degree bow up difference at speed, tabs full up. Seems low but don't have any data to compare.

Thanks - Greg

Thanks. Just trying too see if our trim is close to typical since the CATs weigh about 1000# each less than original detroits and wondering if would shift cg forward enough to tell a difference. Eyeball comparison of where the spray comes outside the hull sides and I can see it and comparing to a Post 42 brochure photo it seems similar, but not a very precise measurement. I haven't found someone to get a nice side view running at speed yet.

I really haven't looked at speed with a little tab as it seems to handle best under normal conditions with the tabs up, and I don't need to use the tabs to get on plane.

The prior owner did the repower so I have no expierence prior to the change for comparison. My fast boat experience, where only the back half of the hull was in contact with the water, is not helpful.

I design aircraft so spend half of my life on the exact placement of every system and component for best handling and performance. In this case I have no data on the balance prior to or after the repower to even determine if a significant cg/trim change would be possible. If the engines were/are at or aft of the cg, the cg would shift forward with reduced engine weight and decrease the running angle. Since the engines are also 18" shorter, the actual engine cg moves aft along with the reduced weight, which may or may not conteract the actual weight loss. As an engineer having no useable data is not satisfying.

I played with the boat on the way home from the weekend trip in a moderate 1 to 1.5' wave to see if removal of the original owner added 'spray rails' was good, bad or indifferent. I think it was better as I could run a very shallow crossing angle on the waves (running across them 10-15 degs off beeam) and did see less roll and almost no steer-off on crossing. I also played with the AP and running heading mode, it is faster to respond than I am, further reduced the roll but I don't know if that will persist in larger seas.

I would like to know where the bottom actually enters the water along the length and if the current location is close to the original design intent or not. Our boat is faster than most other of the period, and it is obvious in rougher seas that it 'likes' 22 kts more than 24-25. It gets noticibly light on the pins at 29-30 kts. It also 'seems' to like keeping 100 gallons more fuel in the aft tank (the forward tank, between the engines, is 200 gal capacity, the aft tank under the cockpit floor holds 350). Just trying to explore the boats capability and get more comfortable. My Scorpion Racing hull would go through anything, so I need to adjust my expectations.

Thanks for the info.

Was able to get some aerial video with a friend. Video is on a very flat day in the river so I could see running attitude without wave interactions. Still shots are cruise tabs full up at 20 kts, 22 kts and 24 kts. Open to comments. I think a little tab at 24kts (and above) is good. I did play with adding a little on recent trip before I had the video and a little tab brought 24 kts to 25 kts. That run was also on a pretty flat day.

I'm not opposed to running tabs down per say. Before we removed the (original owner added) bow 'spray rails' I felt that the bow wouldn't trim up enough, expecially in following wind/seas. Now that the add-ons are gone I wanted to see how the running attitude compares to other Posts (the new 42 is basically the same hull and have photos of it from the brochure). It also seemed like the Post ran with the bow lower than our prior 35 Viking, but some of that could be the optical effect of the shorter foredeck of the Viking.

The first time I saw a performance increase trimming the bow down a bit at higher speeds was a couple weeks ago with the old rails removed. Removing the rails also did what I hoped and greatly reduced the roll when crossing steep waves/wakes.

The CATs have electronic sync and display fuel flow, %load the boost to make sure they are sharing the load. The props were blueprinted by Black Dog and speed coated. I'm not really concerned with Nmi/gal (which is also displayed) or even speed but looking for best sea keeping and smoothest ride.

I considered Humphries interceptors, but the installed cost at $30-40k was more than I'm ready to spend. At least for now.

Considered as option for the roll vs cost of removing the spray rails. Removing the add-on spray rails made a big improvement. Still has some roll in cross swell that tabs are much to slow to impact, dynamic system would be able to react. Mostly I play sailboat and tack back and forth to keep crossing angles to side swells better.

I admit I was spoiled by the sea keeping my Scorpion Racing CC (their record holding race boat hull) had.

The Chesapeake is long, fairly narrow, and shallow a long way out along the edges. Often not much choice in heading. Side swells from the rivers on outgoing tides can extend much of the way across.

My wife doesn't complain about the ride but the cat does.