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3.1 Waves Too Big for Floatplanes with Ultra Setting

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http://www.peardrop.co.uk/beaufort.htm

 

First of all, in RL I have never flown any kind of floatplane and my experience is limited to being a passenger in a Huey with floats. A sustained 8kt wind is hypothetically going to give you almost 3 foot swells and that seems a little challenging for a floatplane. I'm also wondering here about the P3d bathymetry setting (one of the more mysterious aspects of the sim). I've read a wide range of opinions on how bathymetry affects wave height in the sim and I am still not convinced what the actual relationship is.

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True, waves and surface wind don't always go hand in hand. Not sure what you mean by big hole? P3D reduces wave heights on inland water vs. major water bodies (oceans). I took off from a inland water body so smaller waves ...

 

 

 

 

 

https://www.youtube.com/watch?v=GIpVw-97mKo

 

https://www.youtube.com/watch?v=LJCt0UAzBTI

 

This is probably the worse conditions I could find

https://www.youtube.com/watch?v=2X-5YEgsQhw

 

If they do take off in worse conditions, then I guess I haven't found a real world video ... I did search ... most seem to takeoff and land is pretty good conditions. But per your link ... 8-12 mph (I think they mean knots) seems to be the preferred threshold.

 

But like I said, don't know if there is something in the SDK for aircraft model to adjust or if it's something hard coded. But it's certainly not "impossible" to take-off.

 

With that said, I'd love to see a ground up development of a seaplane for P3D V3.x not a "converted" ... but I heard a rumor Aerosoft might re-work the Otter for P3D V3.x ... not sure if that rumor is still alive or not, haven't seen the CRJ yet ... maybe in another 5 years ... doooh! hehe

 

Cheers, Rob.

Appreciate all the legwork there.

Didn't realize P3D does lessen the inland waves.

 

In terms of examples...I am actually a real life seaplane pilot and inland and in lakes we *absolutely* operate in up to 20kt winds.

 

The water stuff is a tough model. Is P3D modeling wind shadows on water that are behind land masses?

 

In the PNW you get some really interesting situations of high winds with basically no waves (or very little) due to the large mountains coming right out of the water. Tough one for P3D...no question.

 

Seaplane operations vary widely by region, terrain and water body types and equipment. Inland 20kts vs Caribbean 20kts (or any ocean ocean scenario) obviously vary extremely.

 

Agreed. It would be excellent to see a legit seaplane developed.

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Just looking through some of those videos and around the web....

 

I need to get a GoPro...I had no idea how much hairy stuff I've encountered in seaplanes that apparently nobody has put on YouTube yet!  :-)

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The water stuff is a tough model. Is P3D modeling wind shadows on water that are behind land masses?

 

No -- but I believe this can be done to some degree - it would be an expansion of how thermals are implement around mountain regions -- however you are going to need a high degree of accuracy (read, performance penalty).

 

As for water, P3D does use Bathymetry data (SDK defines the global locations the data it's available for - surprised 3rd party haven't picked on this and extended it to entire globe) to influence wave height and I recently found out that Bathymetry data is always used regardless of whether or not one checks the box in the Graphics settings ... that box is primarily to just enable the underwater visuals, use of Bathymetry data is always enabled.

 

There are some things in regards to currents, river flow, etc. that might get implemented in the future but I can't discuss that.

 

Yes, get a GoPro and record some flights, I'd watch it ... I soak up stuff like this:

 

 

Cheers, Rob.

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There are some things in regards to currents, river flow, etc. that might get implemented in the future but I can't discuss that.

Rob thats all sounds awesome but you are an awful tease! :P


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Hi folks,

 

Found on LM forum:

 

Add this statement to the [Contact Points] section of the aircraft.cfg
always_use_avg_surface=1

 

And it works like a charm ! :wink:

Thanks to the OP goes here:

http://www.prepar3d.com/forum/viewtopic.php?f=6312&t=116746


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Thrustmaster Controllers: TCA Yoke Pack Boeing Edition + TCA Captain Pack Airbus Edition + Pendular Rudder.

 

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Some may call me crazy...I prefer it set to none with all reflections enabled :)

 

king.jpg


---Brian Bash---
398 HR MEL PPL and climbing!

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Hi folks,

 

Found on LM forum:

 

Add this statement to the [Contact Points] section of the aircraft.cfg

always_use_avg_surface=1

 

And it works like a charm ! :wink:

Thanks to the OP goes here:

http://www.prepar3d.com/forum/viewtopic.php?f=6312&t=116746

Thanks for the tip, but having mixed results with this. Been playing with avg_sfr on and off with the Twin Otter Extended.

 

On it definitely solves the bouncing, but seems to almost negate the waves entirely with major water clipping. Seems to essentially mush entire plane through water/waves.

 

Off its the bouncy/twitching described in this thread.

 

Not the silver bullet I was hoping for. Maybe the entire contact points settings all need to be tweaked?

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In terms of examples...I am actually a real life seaplane pilot and inland and in lakes we *absolutely* operate in up to 20kt winds.

 

Then, as you know, due to the limited fetch of most inland lakes and ponds, wave heights are vastly reduced when compared to marine waters.

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Then, as you know, due to the limited fetch of most inland lakes and ponds, wave heights are vastly reduced when compared to marine waters.

Of course. What's your point?

 

The hope for more detail in that type of modeling was talked about above in this thread. See the part about wind shadows and the modeling challenges, etc. applies to ocean, inland, rivers, lakes... everywhere.

 

Big part of seaplane flying.

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My point was that you made a case for being able to operate a seaplane in 20 kt winds. My point was that an inland lake is not the ocean when it come to the relationship between wind speed and wave height.

 

Anyway, I'm still at a loss to understand how the bathymetry in P3d influences wave height. If so, most inland waters have no bathymetry terrain mesh, so whatever impact that it does have would be zero.

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Anyway, I'm still at a loss to understand how the bathymetry in P3d influences wave height.

 

Here ya go Jay and others ...

 

[contact_points]
static_pitch=0.0 //degrees, pitch when at rest on the ground (+=Up, -=Dn)
static_cg_height=0.0 //feet, altitude of CG when at rest on the ground
always_use_avg_surface=1 //always use the average surface elevation
 
My Question:
 
Hi Beau,
 
My assumption has always been that Bathemetry (enabled) will also impact wave height ... reducing waving height inland (at those locations that have the Bathemetry data). But I think you mention in the past that Bathemetry data is used regardless of it being enabled/disabled and that setting is just for visuals under water? Is this accurate or am I way off?
 
Cheers, Rob.
 
Response:
 
 Beau Hollis 
 
Yes, bathy data is used for dampening regardless. Water depth is where there is not real bathy data is based on water classification to get around huge ocean waves showing up in small rivers and ponds.
 
--------------------------------------------------------------
 
I read this as being a little of both.
 
Cheers, Rob.

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My point was that you made a case for being able to operate a seaplane in 20 kt winds. My point was that an inland lake is not the ocean when it come to the relationship between wind speed and wave height.

 

I agree. I sort of felt that was said in here already. (See below)

 

True, waves and surface wind don't always go hand in hand....

 

....P3D reduces wave heights on inland water vs. major water bodies (oceans). I took off from a inland water body so smaller waves ...

 

(Although some lakes are different of course...like Great big ones!) :-)

 

Anyways, I'm sorry it was confusing if it was.

 

In either case...none of this addresses wind shadows on the water from terrain influences (see Rob above in this thread).

 

 

 

A great example of how cool it would be to have the terrain impacting the waves and water are ocean bays and peninsulas.

 

You can have seaplane operations on "oceans" simply landing in a bay around a corner or behind a hill or peninsula of terrain that protects an area from any wind waves building.

 

That is technically "ocean" in P3D yet in areas of protection the water conditions would behave much more like a piece of river or a small lake.

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Response:

 

 Beau Hollis 

 

Yes, bathy data is used for dampening regardless. Water depth is where there is not real bathy data is based on water classification to get around huge ocean waves showing up in small rivers and ponds.

 

--------------------------------------------------------------

 

I read this as being a little of both.

 

Cheers, Rob.

 

 

 

Rob, Thanks. It seems like what Beau is saying (Haha, this might end up like the Monty Python Oscar Wilde sketch) is that the different smaller inland water classes have a list of constants that provide various levels of dampening, so that small waterbodies don't show unrealistic wave heights.

 

The Triton SDK is pretty sophisticated in the way it generates ocean waves:

 

http://sundog-soft.com/sds/2014/06/integrating-ocean-wave-models-triton/

 

The different models that can be used are described here:

 

http://www.wikiwaves.org/Ocean-Wave_Spectra

 

But beyond all that it appears that for marine waters, LM took an empirical approach in addition to what wave heights are generated by the Triton SDK. P3d appears to just dampens the wave heights in marine waters that have bathymetry mesh as the water gets shallower. It's probably just a simple equation of some sort:

 

Depth-dampened Wave Height  =  Triton SDK Wave Height *  ( depth ) / ( B0 + depth )                 (or something like that, where B0 is a constant.)

 

Your earlier video with P3d 2.4 shows that:

 

 

That works fine until one gets very near the shore, but P3d doesn't generate a legitimate breaker zone, nor should it be expected to do so. That effect would probably be better simulated with animated textures.

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A great example of how cool it would be to have the terrain impacting the waves and water are ocean bays and peninsulas.

 

And lets not forget currents also ... this is definitely all cool stuff to implement in the future, but it would need to be compromised some to be viable for hardware 5 years from now :) ... definitely NOT doable in a 32bit address space.

 

Cheers, Rob.

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