GP21 Hull Ride / Behavior Questions

[serge]

The study plans state:

"good planing characteristics"

and

"smooth running in a moderate chop"

What does good planing characteristics mean?
Will it not raise the nose sky high when getting on plane?
Can it plug along at 15 mph when the weather turns to s&%t without dropping on and off plane?

What's the definition of moderate chop?
1' to 2' short steep confused Tampa Bay wind blown crap?
2' wakes from the condo cruisers?
Or limited to 6" wind blown ICW stuff as a definition?

I really like the utilitarian and load carrying attributes of the hull.

Comparing that to the 25' panga mainly.

Just curious how much of the ride I'd give up vs the panga for the extra floor space and capacity.
Size of engine and fuel economy are non factors.

Thanks for reading and looking forward to some opinions and answers.

Serge

[fallguy1000]

Almost zero planing craft can maintain 15kts in heavy seas.

The big heavy Bertrams can. The Skoota is a semi displacement craft and rumored to perform best between 12-15kts in heavier seas.

In my opinion, neither the GP21, nor the Panga 25 are ideal for Tampa area gulf excursions, but I'd rather be in the Panga modified some.

[fallguy1000]

Both boats will be fine in a 2' chop; how fast is up to comfort of capt n crew. I slow down.

[rick berrey]

I am not sure about the GP21 in chop , but there are post by Jacques on the Panga 25 in chop . A panga makes a great gulf boat , a 25' panga will slice through 3' chop , with ease and anything over that starts to be a rough ride in any small boat

[TomW1]

You should have no problem cutting through a 2' or even a 3' chop. Jacques designed the cutwater to be 26 degrees. You may have to slow down with a 3' chop but you will get home. A lot depends on the experience of the skipper and his familiarity with his boat and the area he is in. These boats are strong and can take a lot more than most fiberglass boats, so remember that.

I love the Panga's and a Panga25 would also be a good choice. HP wise you would need less on the Panga than on the GP. Also with an 8" draft the Panga's DWL is 650lbs more than the GP21 8" 2000lbs. . PPI for both is over 500lbs, which means you can add 500+ lbs before the draft is lowered by 1".

Good luck on your selection.

Tom

[BarraMan]

Every boat is a compromise in one way or another. The trick is to pick a hull that best meets your general need and then just deal with the other circumstances as they arise.

What's the definition of moderate chop?
1' to 2' short steep confused Tampa Bay wind blown crap?
2' wakes from the condo cruisers?
Or limited to 6" wind blown ICW stuff as a definition?

I have no idea about the Tampa Bay chop but our Gulf chop can be a nasty piece of work. The GP21 is never going to handle a rough sea as well as a panga, but there are things the GP21 will do much better than a panga.

As others have indicated, I think the GP21 will eat 6" wind blown stuff and not be too troubled by your "1' to 2' short steep crap" or 2' wakes from the condo cruisers! I think length is your friend in such conditions.

Even with 26 degrees at the cut-water, I think the 3 degrees at the transom is going to pull you up in really rough conditions if you want to keep your spine in order! On the plane or off the plane at 15 mph (13 kts) - I don't know. May depend on the load. Whatever, carefully driven, the GP21 should get you home safely. It may take a while and you may get wet but you will get there.

My boat is 22', probably has at least 26 degrees at the cut-water and it has 18 degrees of dead rise at the transom. I can sit on 20 kts in conditions that keep others on land, but get pulled back to about 16 kts (just on the plane) in 3' chop and 6 kts in really rough stuff that would be scary without experience with the boat. 6 kts is SLOW and WET but safe, and gets me either home or to shelter! The 'chop' is not the problem for me, its the holes that open up that can result in submarine like behaviour that causes me to slow right down.

Best wishes with whatever you decide!

[Fuzz]

Lee pretty well hit the nail on the head! Longer and heavier are things that will improve the ride.

[Matt Gent]

My opinion is that anyone who has been in 3' wind-driven chop would not recommend a 21' shallow V bay boat to do so. The DE25 is not comfortable in those conditions, I've done that a few times.

Never having seen one (do any exist?) I'd say these probably run similar to a 21 Pathfinder. Or even a Sea Ark has a more similar bottom.

[serge]

Thanks for all of the replies.

About what I figured.

Every boat is a compromise.

Serge

[TomTom]

I think that you will find that a Panga performs much better in the conditions you describe and at 15 mph without "dropping off the plane"...

As Barraman has said you basically will have 2 speeds in bad weather in a GP21 - just before the boat drops off the plane, and then 7 kts or so...

There is a good reason why there are an enormous number of Pangas fishing for a living on a daily basis a little south and west of you ...

If it was me I would build the Panga 25 ...