I’ve loaded the default Icon A5 the other day, took off from a runway and then landed onto the water. Everything was fine except that the aircraft kept sliding forward forever until I killed the engine. I’d say the water should have had more resistance. Is it possible to tune this effect or is it the underlying physics model that is flawed? It was in the default “Clear skies” weather.
Wasn’t sure about this so I checked the X-Plane forums, and a developer there states that even at idle it can push the A5 along on the water. Wind may also be a factor here, and it could be pushing you along.
I think Clear Skies gives you a ground level window of 3-5 knots.
Pushing along is a different thing. I’d expect the wind to push me with the flaps extended, but if it is wind then its effect wouldn’t depend on the engine. However, the airplane stopped when I shut it down.
That’s kind of what that other post was suggesting, that even at idle it could push you along.
I assume a similar thing is occuring here.
I’m sorry, but I can’t quite understand what relevance X-Plane can have here. This discussion is about MSFS.
Forget the sim, look at the behaviour described. Either both sims are wrong, or both are right. Which do you think it is?
Perhaps there is something in an Icon A5 POH about this, but I would go with Occams razor on this one, and assume both sims are right.
Normal behaviour. All aircraft will produce thrust with the engine at idle. (Spinning prop = thrust). It’s just that on land this may not be enough to overcome static friction.
Not so on water.
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The only way to stop forward thrust on a spinning prop is to use beta pitch, which can’t be done with the Icon’s fixed prop. And most planes with constant speed props on piston engines don’t have beta either. You pretty much only get that with a t-prop like the Kodiak amphibian. When you fire up the Icon’s engine on water, either be prepared to move or open the door and toss out an anchor.
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Yes and important enough that all Kodaik amphibians come with a pitch latch prop, allowing it to be started in beta and minimise the thrust on the water when starting up.
Top tip for all: use ‘active pause’ to simulate an anchor. All it does is freeze your lat-long. Which makes it useless as a ‘pause’ function, but surprisingly useful as an anchor!
Some Kodiak pitch-latch
goodness:
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Otherwise known as Newton’s 3rd Law! ‘Every action has an equal and opposite reaction’.
If an aircraft’s propeller is spinning (and not feathered or in beta range) there will be thrust generated, this thrust with cause the aircraft to start to move if it overcomes any opposing forces. On water there is very little static friction compared to land, so the aircraft starts to move forward at idle throttle.
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