I have provided video evidence of all three flap angles of the CAS plane showing how they produce the wrong result.
No flap angle creates the most drag, no lift.
Medium flap angle creates a tiny bit less drag, no lift
Highest flap angle provides the least drag and generates lift i.e. the plane will take off by itself with no controls other then holding X.
Start up the game and record speed and lift for all three flap angles.
Video of the flap angles.
http://www.youtube.com/watch?v=3sf1fLg_pK0
In reality the highest flap angle should produce the most drag.
Second flap angle should create the medium and lowest flap angle should create the least drag.
In my recorded case it´s all backwards.
Then in regards to lift i don´t think the plane should take off at all with highest flap angle because drag will overpower the lift being generated.
medium flap angle should have medium drag and probably also allow the plane to create enough lift to take off by itself.
lowest flap angle should produce the highest acceleration, the least drag and little to no lift at take off speeds.
From my testing.
Try just accelerating down the runway and note speed at end of runway.
Flaps Speed Behaviour
Zero 190 kmh On the ground still.
One 207 kmh Feeling a little light but still on the ground
Two 235 kmh Flying.
That actually looks ok to me.
With zero flaps it should stay on the ground due to the symmetric airfoil
With one flap it it light due to a mslla amount of lift. Being in ground effect and the wheels not dragging as much we could expect a bit more airspeed.
With two flaps. Assuming the jet has the thrust to counter the induced drag it would take off.
So. Could it not be that at full flap the aircraft getting "light" due to lift then into ground effect helps it accelerate to where it takes off? The flaps don't seem particularly large to induce massive drag.
I will say I expect that kind of behavior from one stage of flaps and stage two would probably be too draggy for takeoff and used for approach only but that is based on my own plane. I don't own one of these jets!
I can't say I see any effect on stall speed in flight though.
Just the plane in general, the way it feels and handles in the air seems exactly the same as it was in.ArmA 2. I would dare to say that the physics engine isn't affecting the plane's performance im the slightest, same with helicopters.
Um if i'm not wrong, during takeoff, both lift and drag are pretty significant, but only when the flaps are deployed.
However, i believe that with flags deployed, you should be able to takeoff at a lower airspeed than without them, as they generate more lift at lower airspeeds.
I just read your ticket again,
"Then in regards to lift i don´t think the plane should take off at all with highest flap angle because drag will overpower the lift being generated."
That's absolutely incorrect. You need flaps for both takeoff and landing. Lift and drag are proportional to the angle of the flaps, and as i mentioned before, higher flap "angle of attack" allows greater lift at lower airspeeds, allowing you to takeoff sooner.
"That's absolutely incorrect. You need flaps for both takeoff and landing. Lift and drag are proportional to the angle of the flaps, and as i mentioned before, higher flap "angle of attack" allows greater lift at lower airspeeds, allowing you to takeoff sooner."
No you are miss-understanding the point.
The most extreme flap angle is only used for landing, not for take off.
It´s there for landing, not taking off. Medium flap angle is for taking off.
You are absolutely right that it´s proportional, but you are completely disregarding that drag will overpower the lift because the drag will inhibit the plane to reach enough velocity to take off.
IT´s the same with F1 cars where eventually the downforce becomes so much that drag will disallow the car to hit it´s top speed it´s geared for.
Imagine a graph, vertical is lift, horizontal is speed.
The line can´t split itself so you need to choose what you want, with maximum flaps you go up the graph, with lowest you go horizontal.
Middle is a perfect ratio of taking off while maintaining enough speed to actually lift off the ground.
Confirmed, flaps physics need a lot of work. Stall speed should be significantly lower for high flaps settings. Also there should be more drag when using flaps but not so much.
0 flaps - normal stall speed, normal drag
1 flaps - lower (maybe 20-30kmh) stall speed, higher drag
2 flaps - landing stall speed (maybe 150-180kmh), most drag allowing to slow down plane quickly.
Also it shouldnt be possible to lower flaps at more than, say 300kph.
Yea that´s another thing, when in flight, changing flap settings has no effect on drag at all.
In fact i think i registered some increase in speed with the most extreme setting.
Should be easy to just switch it around and maybe make the most extreme setting more powerful so it actually starts to slow the plane down while in flight.
Speed is solely controlled through X and Z right now.
@RushHour yes i think you're right, sorry :)
Though, i remember playing a flight sim (F/A-18 Korea) where i could takeoff with max flap angle as well...though i went through the game's training videos and manual, i think max flap angle is indeed used only for landing, as it's not mentioned anywhere else.
But other points here are undoubtedly valid, higher angles should reduce ground/air speeds not increase them.
To add to what prykpryk's said in the end, usually aircraft automatically retract flaps and gear beyond a certain speed.
No problem, we are only human ;)
The great thing about this is that it should be an easy fix i think.
"Also it shouldnt be possible to lower flaps at more than, say 300kph." At some speed it should probably rip the flaps/wing off but none of that damage modelling or weight changes (weapons firing) is modeled in ARMA it seems which to me is not surprising. Infantry game...
I decided to look into it more so I talked less in generalities.
Stall speeds from the Albatross data sheet though there may be variants...
Clean: 195 kmh
1 Stage: 176 kmh
2 Stage: 165 kmh
These should be at max takeoff weight.
Doing a test flight I get these numbers:
Clean: 155 kmh
1 Stage: 155 kmh
2 Stage: 162 kmh
I'm using a mouse so it was a bit hard to get completely accurate numbers but I pretty confident that there is something amiss.
I did like how squirly it was near stall. A lot like my plane. I would like a good snap roll on stall but not even flight sims manage that well :-(
As for should it able to take off on full flaps. Depends on whether the engine can overcome the high induced drag AND ground friction long enough to get airborne. I can't find anything that says anything about it.
As to automatic flap reduction. Some modern jets have them but this isn't a modern jet. It is a cheap ancient thing used by underfunded factions!
As to "higher angles should reduce ground/air speeds not increase them". Absolutely true in flight. Bit of a warning sign that one :-)
maybe the gear touching the road, make more drag, and more lift, make the gears touch less making less drag... maybe? I don't know in reality how it work
That´s friction coefficient you are talking about. But no, the effect is the same up in the air as well.
Now that I've tried it, i think the whole flight model is flawed in Arma 3...ignoring the fact that a drone can fly at mach one... :/
What they need to do is look up the physics of all the aircraft they implement in the game, and go off of that. Structuring flight models from their real life counterparts, is something that BI SERIOUSLY needs to look into. This way, it creates the balanced and polished feel of what the game needs. You get my vote on this one. +1.
IMO they need to implement a generalized flight physics system that applies to all aircraft. That system would calculate aircraft behaviour based on the aircraft's physical model in-game, and other inputs like wind speed and direction.
I think X-Plane does it like that.
Flaps Speed Behaviour
Zero 190 kmh On the ground still.
One 207 kmh Feeling a little light but still on the ground
Two 235 kmh Flying.
You can't use those speeds. Stage zero at 235 km/H you will also be flying ...
@Thx1164 : Thank for your tests. If you need to perform further test i've everything to pilot, so i could help you if you want.