Heading in with following seas of approximately 5-6 feet and piloting the PG25 at a speed consistent with the waves. When a wave passes underneath,my Panga lifts up at the stern and drives the nose into the trough of the next wave. She is momentarily out of control and starts to slide sideways on the wave and nearly pitch pole. My stomach drops for a split second and it feels like it’s going to flip. She then gains direction and continues to “surf” home.
I have a 90 h.p. Honda with plenty of power. She is not overloaded. I built her with the standard plan design of an 1 1/2” skeg held back 18” from the stern.
My question for the forum: is there anything I can do to improve the design and help her drive straighter. Some thoughts are a bigger skeg? Shorten or lengthen the skeg? Add some “tunnels” in the bottom? I have nearly 2000 hours of driving a boat on the ocean so it’s not an amateur piloting problem. With the 7 degree of dead rise and a small skeg, I’m not really sure if there is a solution, but I thought I would ask. Otherwise, I’m very happy with the boat!
I have over 175,000 views on her build video on YouTube!
Panga 25 Nose Dive
-
- * Bateau Builder *
- Posts: 3041
- Joined: Sat Dec 07, 2013 11:29 am
- Location: Marin County, CA
- Contact:
Re: Panga 25 Nose Dive
Congrats on the build views. I've got...I dunno...ten.
Anyway, I'm not a powerboat guy and so your experience trumps anything I'd have to say.
But it would depend on the steepness of the seas, it would seem. 6' at, say, 10 seconds is no big deal, totally comfortable. 6' at six seconds is small craft advisory territory. Not sure many boats would be happy in that.
Anyway, I'm not a powerboat guy and so your experience trumps anything I'd have to say.
But it would depend on the steepness of the seas, it would seem. 6' at, say, 10 seconds is no big deal, totally comfortable. 6' at six seconds is small craft advisory territory. Not sure many boats would be happy in that.
Tony
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: Panga 25 Nose Dive
You can't overtake any waves that size in a light, long, narrow ship without some fun.
All boats have weaknesses.
You want the bow up, so you could trim up. It wouldn't take much. But worth a try so long as you don't lose steering.
My 16' Lund is a very unsteady critter in heavy followers. The seastate dictates my every move. Every second I am deciding to flow or go over, etc. In a heavy head sea, I get waves over bow now and then, but the boat performs better. The boat is wide and stern heavy.
We always get real careful on Superior in the afternoon. If it builds to 6 footers; we are done.
The pangas are designed for efficiency; they have a long length and narrowish beam; the pitchpole sensation is the nature of the vessel. But unfortunately; even at 25' long; you are limited.
Try trimming up engine or leveling with stern livewells or weight shifting.
All boats have weaknesses.
You want the bow up, so you could trim up. It wouldn't take much. But worth a try so long as you don't lose steering.
My 16' Lund is a very unsteady critter in heavy followers. The seastate dictates my every move. Every second I am deciding to flow or go over, etc. In a heavy head sea, I get waves over bow now and then, but the boat performs better. The boat is wide and stern heavy.
We always get real careful on Superior in the afternoon. If it builds to 6 footers; we are done.
The pangas are designed for efficiency; they have a long length and narrowish beam; the pitchpole sensation is the nature of the vessel. But unfortunately; even at 25' long; you are limited.
Try trimming up engine or leveling with stern livewells or weight shifting.
Re: Panga 25 Nose Dive
Panga Ron have followed your posts since you started to build that lovely boat. First a Panga really isn't designed for 5-6' seas. Second the way to improve the handling is to deepen the keel to 6" and extend it forward so it is 1/3 of the boats length or 8 feet in your case. So taper it from 0 to 6inches at the transom. This should improve your handling immensely in rough water that you described. Cracker Larry went through 10' waves with his 6" keel on his OD18
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978
-
- * Bateau Builder - Expert *
- Posts: 6725
- Joined: Thu Sep 13, 2007 9:13 pm
- Location: Dade City, Florida
Re: Panga 25 Nose Dive
Depends on the Captain Tom. But yeah, basically correct.First a Panga really isn't designed for 5-6' seas.
Yes, correct. I had a 32’ relatively narrow single engine boat with a 12” skeg. Sometimes it would slide sideways coming down off a 6-8’ wave in a following sea. The skeg did wonders in snapping the boat back straight in the bottom of the wave trough.Second the way to improve the handling is to deepen the keel to 6" and extend it forward so it is 1/3 of the boats length or 8 feet in your case. So taper it from 0 to 6inches at the transom. This should improve your handling immensely in rough water that you described.
Hmmm, I don’t remember it being that tall.Cracker Larry went through 10' waves with his 6" keel on his OD18
Richard
Completed boats...XF20 "Red Alert", Aripeka Angler's Strip Canoe, FS18 “Bare Bones”, GF12
Currently building...PY12 Kayak
viewtopic.php?f=12&t=62146
Completed boats...XF20 "Red Alert", Aripeka Angler's Strip Canoe, FS18 “Bare Bones”, GF12
Currently building...PY12 Kayak
Bare Bones build thread...If there is magic on this planet, it is contained in water. - Loren Eiseley
viewtopic.php?f=12&t=62146
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: Panga 25 Nose Dive
There is probably a top end tradeoff, no? Can a skeg affect the prop/stern height cav plate?TomW1 wrote: ↑Sun Aug 09, 2020 4:02 pm Panga Ron have followed your posts since you started to build that lovely boat. First a Panga really isn't designed for 5-6' seas. Second the way to improve the handling is to deepen the keel to 6" and extend it forward so it is 1/3 of the boats length or 8 feet in your case. So taper it from 0 to 6inches at the transom. This should improve your handling immensely in rough water that you described. Cracker Larry went through 10' waves with his 6" keel on his OD18
Re: Panga 25 Nose Dive
That broaching will happen with a certain wave height and period for almost any boat. Was the wave period particularly short?
I assume that you have tried different speeds and engine trim. Are you able to trim the bow up in that situation?
The idea of a larger skeg (it becomes a small keel) is good but there will be a price to pay in performance. If you plan on using the boat often in those conditions, I would add some keel area.
Another addition that may help is very wide spray rail along the forward part of the chine but I see you already have a spray rail.
I assume that you have tried different speeds and engine trim. Are you able to trim the bow up in that situation?
The idea of a larger skeg (it becomes a small keel) is good but there will be a price to pay in performance. If you plan on using the boat often in those conditions, I would add some keel area.
Another addition that may help is very wide spray rail along the forward part of the chine but I see you already have a spray rail.
Jacques Mertens - Designer
http://boatbuildercentral.com
http://boatbuildercentral.com
Re: Panga 25 Nose Dive
Will a deeper skeg/keel increase the chance of tripping/flipping if the boat does end up grinding sideways down a wave face?
There are only two seasons in Vermont: boating season, and boat-building season.
Completed Paul Butler 14' Clark Fork Drifter
Completed Jacques Mertens FS14LS + 10%, Build Thread
Started Iain Oughtred Tammie Norrie
Completed Paul Butler 14' Clark Fork Drifter
Completed Jacques Mertens FS14LS + 10%, Build Thread
Started Iain Oughtred Tammie Norrie
- cape man
- * Bateau Builder - Expert *
- Posts: 8282
- Joined: Sun Jan 20, 2008 12:02 pm
- Location: Lithia, Florida
Re: Panga 25 Nose Dive
Tom W you now own that OD, and unless you post a pic of a 6" "keel" I'm calling bs. Larry was about 2 months ahead of me and I was pretty much copying his work on my OD. The "keel" we installed together on mine is a 1x1" piece of pine - a skeg covered with an aluminum shoe.
I assume it works well, but can't say as it has always been there. The OD is awesome in a following sea, but you do have to match the speed of the waves to make sure you are not coming down too fast. I do trim the bow up in even a following chop.
The huge disadvantage to a deeper skeg is obvious if you run in shallow water.
Panga, is there anyway to shift weight aft in that situation?
I assume it works well, but can't say as it has always been there. The OD is awesome in a following sea, but you do have to match the speed of the waves to make sure you are not coming down too fast. I do trim the bow up in even a following chop.
The huge disadvantage to a deeper skeg is obvious if you run in shallow water.
Panga, is there anyway to shift weight aft in that situation?
The world always seems brighter when you've just made something that wasn't there before - Neil Gaiman
-
- * Bateau Builder - Expert *
- Posts: 10205
- Joined: Tue Jan 12, 2010 12:25 am
Re: Panga 25 Nose Dive
I think Tom extrapolated the skeg from the od18.cape man wrote: ↑Mon Aug 10, 2020 6:29 am Tom W you now own that OD, and unless you post a pic of a 6" "keel" I'm calling bs. Larry was about 2 months ahead of me and I was pretty much copying his work on my OD. The "keel" we installed together on mine is a 1x1" piece of pine - a skeg covered with an aluminum shoe.
I assume it works well, but can't say as it has always been there. The OD is awesome in a following sea, but you do have to match the speed of the waves to make sure you are not coming down too fast. I do trim the bow up in even a following chop.
The huge disadvantage to a deeper skeg is obvious if you run in shallow water.
Panga, is there anyway to shift weight aft in that situation?
I am concerned about greenwater running issues with a deep skeg all the way to the transom. No experience, just curiousity.
Who is online
Users browsing this forum: No registered users and 6 guests