Definition of Planing

Ground effect is relative to the wing length or rota diameter. of course there is guaranteed dispute on this.

 

If you flew off a cliff in a helicopter it would tople and crash because of ground effect.

Ground effect becomes inconsquential after 3x dia of rotors of height.

( i think its 3x )

 

Because of ground effect or lack of ground effect ????? Any way what has this got to do with planning!!!

 

hello I am new here, english is not my mother language....

but I read this intresting treat and more the least time

is that idee of MoeJoe correct that in a pool the water level will fall if a modell starts to plane??? I mean in a very deep pool with no ground effect

there is no lift possible without a downwash, so behind the boat some water will sinking down, can it be that in case of constant planing speed there must be a hole in the water behind the boat , ----> and the waterlevel stay constant??? at any speed?

in the first moment it sound crasy, but if we put the pool together with the modell on an accurate scales, and let start the modell and if then the waterlevel falls down a little bit, then all together will be lighter than before

but we can not loose weight in this case at all, not if the boat stand still and not as long as it moves with constant speed on a stable horizontal way, there is no place for the lost weight in this system, or where will it be???

are all bow waves of a planing boat in there sum together a wave trough??? a trough with a volume in equivalent to the dynamic lift??

 

I think you mean that when you look aft on a planing boat, the hole in the water looks like the bottom of a double-ender. You propose that the weight of that volume is equivalent to the dynamic lift on the boat. I would say that the weight is much higher. There is energy displacing the water that is not all producing lift.

 

You would have to take into account that atmospheric pressure has a big effect..like low pressures and high pressures of the weather. Also gravity influences water levels. when water is displaced as with the effect of of a propeller accelerating the water back behind the boat or forward movement of the boat gravity and atmospheric pressure push the water back in place.

 

This is one of my many Myark trailer barges I built which I design the back and front ends with a slight rise so the barge when propulsion is applied will rock up in the back end and run level with water which the picture shows planning with two twenty five horse power out boards that gives good speed and gas performance for a landing barge this size.
Also the Myark barge is the trailer that has torsions suspensions plugged into the hull, again making it good on gas when towing and been able to be towed by lighter vehicle because of the weight reduction of not having a heavy trailer to place barge on top.
This trailer system also allows beach launching and retrieving in surf conditions also in remote areas where no boat launching ramps are available.

 

aaaahhhh Hes back !!

Ahhhh but do you know when its plannng ??? No one else seems to know !!:idea:

 

Sorry I do not understand what you say.

 

It's okay Myark, there has been considerable nose picking going on here with this thread, meaning the computer desk "intellectuals" can't actually decide when a boat enters that magical moment of planing - plus many of the pontificates seem also to have trouble deciding whether they are planning or planing.
Confused. Don't worry about it. Your excellent powered barges plane without the help of the punters here.

 

It's a strange phenomenon to get so annoyed at others working on a theoretical question because you are incapable of understanding the question or disinterested in the question personally.

The thread is about developing a definition of "planing". The difficulty is specifying exactly the moment when a boat goes from not planing to planing and a definition that applies to atypical boats. To answer the question "at what speed does this boat plane with 400 lbs of fuel and 400 lbs of people aboard" a definition is necessary to specify planing exactly. A second application is atypical boats that may or may not be considered planing boats by different observers.

 

I know what the thread is about and I decided to cut the mumbo jumbo and show a working 8. Landing craft in an ABC explanation that has 2 x 25 hp out boards to have good performance and then gave the reasons why.
I have also built a 12.m X 3.6 barge with the same bottom and had high performance with an 115hp out board for an ouster farmer who could not believe how fast it could go with load on top.

There is no rocket science about how this boat plans which is faster than others that I know of with more HP.

Tunnels is eccentric and is hard to understand but would like to thank Gary baigent for his kind comments.

 

This is the barge that had a 115 hp

 

This is the Myark 10. X 4.8 folding trailer barge that easily plans with a 60hp out board motor because of the slight rise in the front and back bottom hull.

 

In theory planing and planning are the same, in practice they are not ?