Helicopter/aircraft improvements.

[apex_predator 0]

Sorry, YouTube didn't like the underscore in the filename

This is the example, notice that in the last portion the entire body of the helo deviates from a fixed point on the ground (the conical mountain on the beach). If the camera and helo were rotating on the yaw axis around a fixed point at or near the rotor hub then the helo would continue to fly on the same course, thus keeping alligned (or nearly so) with the nose of the aircraft when it passes through center during oscillation, which it clearly does not.

http://www.goldfalcon.org/armayaw.wmv

I'm no military chopper pilot, but I have ridden in, parachuted out of, slung load stuff to, and seen enough of 'em manuevering in action, to know that this is not how one handles, and to my eyes it appears that it is due to an incorrect point of rotation on the yaw axis.

*Edit* I'm gonna pull out the snarky bit and blame it on nicotine withdrawals. I consider the hatchet buried at this point.

[max power 21]

In order to measure whether the pivot is at the camera, you must see what the camera is doing. In order measure what the camera is doing, you must see the ground close to the camera. In order to do that, you must be low to the ground or on the ground. This video gives you no perspective and therefore no information on if the camera is moving, therefore no information on whether the pivot is in front of, behind on in the centre of the helicopter.

[apex_predator 0]

That's an understandable objection. Here ya go:

http://www.goldfalcon.org/armayaw2.wmv

In that view it seems to me that the pivot poit is at (or very near) the chase camera. To me it is also interesting that if one rotates the camera to above or below the aircraft the pivot point seems to move with the camera. I can post a video of that too.

[max power 21]

So is your argument that this only happens at speed or what? This video again doesn't show anything. I would suggest that you find someone to test this out with online so that one person can fly an helicopter and another can film either in a chase plane or from the ground. You need more than just the helicopter and the camera and some distance scenery. You need to be able to see the ground (or ocean) between the camera and the helicopter, or to view the helicopter from an external frame of reference.

BTW, congratulations on trying to quit smoking if that's what you're doing. It's one of the more difficult things in life, and is quite a test of will, especially in the early stages.

[apex_predator 0]

Yes, my hypothesis at this point is that in hover (or near hover) the pivot point is near (or nearer) the rotor hub. But at increasing speeds the pivot point is calculated to "slide" to the rear, eventually ending up near the camera. Elongating the arc in this fashion would accomplish (in theory) the real life effect of severly decreased input from the pedals that does in fact occur in real life with increased speed.

What interests me most is that the rotation axis seems to be tied to the camera; that is if I rotate the camera under or over the helo the rotation axis seems to shift.

Could I be wrong? Sure I could. It could be an optical illusion. But the yaw feels off and I am unable to replicate real-life manuevers in both fixed wing and rotary wing aircraft, and after reading Maruk's post on having the roll axis above the rotor cone it started me poking.

All I wanted to do was start a discussion.

I like the suggestion of the multiplayer chase camera and I'll test that.

Yes I am quitting smoking, and that may largley explain my confrontational attitude.

*Edit*

I should also not that, just from my personal experience, the roll axis in a helo does shift to "above" the rotor cone at higher speeds in certain aircraft. I also understand that behavior is hard to model. For instance at speeds below a certain threshold (I can't give knots, I was never looking at instruments) a roll feels as if one is in a barrel, at higher speeds it feels as if one is on the end of a Yo-Yo. The cetrifugal force in a roll becomes much greater at higher speeds. I have no reason to believe this same behavior doesn't occur with the tail rotor. That said, I have ridden with pilots who kicked it sideways on the same course coming in at what had to be 60-80 knots and use the fuselage like an airbrake, and I just can't do that in ArmA.

[maddogx 13]

I have created a small script that draws the x,y and z axes of an AH-1Z. After some testing I found that the yaw axis is actually more or less the rotor axis.

Get the demo "mission" I made here.

Try turning the helicopter and looking at it from outside view. You can see how it rotates according to the axes.

[hailstorm 4]

Hey Guys,

After flying these jets around ArmA for a while, and comparing it with my own flying experience, this is what i've concluded:

[note:i know it's a long post, so i've added a synopsis under each explanation saying what i'm getting at.]

- All fixed-wing aircraft are seriously underpowered. it can get to the point where sometimes you have to stand a plane on it's tail to stay airborne, while waiting for the thrust that never comes. this is a bug in itself, but more on that later.

in real life, the amount of useful thrust is not a linear - it's dependant on how fast the aircraft is moving, for example, if it's moving slowly (or it's stationary), the effect generated by engine thrust is at it's maximum - so recovery from low and slow, for instance, should be pretty easy for ARMA jets given the engines they have (i.e. military-grade jet engines). the diagram below shows the effect thrust and drag have on a fixed-wing aircraft at different speeds.

as you can see, thrust is the most effective at low airspeeds, due to the high difference between the air out of the engines and the surrounding environment. drag is low due to the air surrounding the Airframe hitting it with less force. at high speed, the opposite occurs for both thrust and drag.

synopsis: there should be a very good amount of power and acceleration available from all aircraft engines at low speeds.

- Stalling attributes should be changed. in real life, an aircraft is either in a stalled state (ie, no lift being generated by the wings because of low airflow) or not. there isn't really much of a middle ground. any fixed wing pilot will testify that a stall is usually pronounced, with a nose-down action of the airframe, which is due to air hitting the tail surfaces and pushing the nose down in the direction of fall.

in ArmA, Jets' flightpaths will slowly degrade from where the nose points as the speed slows, until the aircraft hits the ground. in real life, with Maximum Power from the engines, aircraft will generally fly in the direction the nose points.

one addition i would really appreciate in ArmA is the addition of a stall warning horn on all the jets - all aircraft have one, so why not ArmA? it'll help players to distinguish the airspeed where they are less flying and more tumbling out of the sky.

Synopsis: planes should either stall, or either fly relatively similar to where the nose points; a stall warning horn should be implemented to warn pilots a few km/h before the plane begins to sink due to low airspeed; a Stall should cause the nose to drop downwards.

- Turn-speed depreciation. lots have people have talked about this - all the way since OFP. personally, i see that it does have some basis of real-life physics, but not completely. yes, if you slam a fighter jet into a 90 degree turn you will lose some airspeed. however, this only happens at high speed. at low airspeeds (looking back at the thrust/drag curve above), there is plenty of excess thrust available, and aircraft such as high-performance military jets should be even able to accelerate in tight, low-speed turns with full throttle.

i want to point out that, fast, high-g turns do burn speed, and most ArmA pilots usually fall for this for one reason: they arn't used to the short visibility of the ArmA engine, and are actually attempting to conduct too small a turn for the aircraft to handle. i believe the turning radius for each aircraft is generally accurate, but i don't think that speeds should burn during low-speed turns, instead decrease to a certain airspeed whereby there is enough thrust to compensate for aerodynamic drag.

synopsis: low-speed turns shouldn't burn speed when full throttle is applied; aircraft should be able to accelerate at low speeds regardless of attitude (alignment).

- Aircraft Weight, Inertia, and Flightpath Deviation. ArmA's model for this is quite odd. at times, you get the feeling that the Aircraft are far too heavy to fly, other times they seem to float on air. things i noticed was that, when entering a turn, the aircraft seems to slide to the left or right, depending on which way you've banked the wings - which never happens in real life. also, in turns, the flightpath lags behind the aircraft's attitude far too much - sometimes, you end up hitting a hill tail first cause you pulled up in time, but the aircraft kept moving straight. this just dosent happen at speed with full throttle! ArmA's aircraft also have an odd attribute - their airframes seem to be slaved to the flightpath, and not the flightpath slaved to the airframe. try this: load up the editor, stick in an A-10, and attempt to point the nose at a point on the ground or sky. notice the nose seems to have a mind of it's own when you relese the controls. now fly it in a turn to the left or right. then, once you're established, quickly roll the wings level. if you did it correctly, you should see the nose fluctuate widly to the left and right. if this happened in real life, you'd have a lot of pilots suffering whiplash! what should happen is that the flightpath should adjust so the aircraft should be flying where the nose (and more importantly, engines) are pointing.

synopsis: Aircraft shouldn't slide along the length of their wings during turns; the flightpath should be dependant on where the nose is pointing, not the other way round.

- Flight Controls. from a in-game point of view,  the Rudders need an overhaul. now in real life, rudders operate on the same principle as ailerons and elevators - they manipulate the airflow over them and result in the airframe (and engines) changing direction, thus changing the flightpath. so why is it that rudders have only a limited effect? what i'm referring to is, why do the rudders only twist the nose 4-5 degrees to the side, then snap it back to the original flightpath when you let go? it's physically possible to turn an aircraft 360 degrees using only the rudder (my flight instructor almost bit my ear off when i attempted to do that back in training). for military aircraft (especially the A-10), which need the ability to point their guns on a target, their rudders are designed to act as a primary flight control. now, from a computer control point of view, i think there should be two things implemented: 'Aircraft' controls to be split into 'Helicopter' and 'Airplane' controls (which has been mentioned by several people), and the addition of sensitivity sliders for both keyboard and joystick axis'. i mean, why is it that if i move my stick slightly to the left, my aircraft rolls like i gave it full deflection? it's too sensitive in the left-and-right axis, but not enough in the back-and-forth. a Calibration option might be a good addition too. Something i miss from OFP was the ability to use the mouse to target enemies. now, with two-seat aircraft (lke the cobra) it's fine, you can still use the command menu, but for single-seat craft, it's almost impossible to target that AA you can clearly see through the front windscreen firing at you, but having to rely on the 'tab' buttion to scroll through available targets to get it. i'm not sure if this is deliberate by BI, but it'd be good if mouse targetting were brought back.

synopsis: implement realistic, constant rudder authority; aircraft controls expanded; the implementation of more sensitivity sliders into the controls menu; and the re-implementation of mouse targetting for single-seat aircraft (if not all aircraft)

- Grass Airstrips. BI need to fix this one. why are the three grass airstrips (one on rahmadi, one at Je-31 (Pita), and at Ja-10 (Antigua)) So rough on aircraft? if they are designated airstrips (which the runway markers around them would suggest) why is it all aircraft, even camels, bounce around on them like it's a dry riverbed? from RL personal experience (i've operated out of grass strips before) it's not a rough ride - especially not rough enough to throw an entire aircraft around. even the A-10 has trouble on these, yet A-10's were specifically designed from the start to be rugged enough to operate from grass strips. also, it's almost impossible for aircraft to get up to takeoff speed on them. personally, i'd like to see these strips given the same properties as roads, or similar.

Synopsis: smooth the Grass Landing strips, so they actually function like airstrips.

Finally, i noticed a few bugs with the aircraft.

For the A-10, it's too tail heavy. if you conduct a Manual Landing in it, and pull the nosewheel off the runway while rolling, you can get it to stand on its' tail - and it won't settle when the plane slows down. so you end up with the plane sitting on it's' tail when it's sitting stationary on the runway with no way of fixing it!

for the for all the jets, they have the odd habit of rotating slowly to the left or right when it's sitting on it's landing gear, on the slightest angled ground. surely such heavy aircraft should sit still where they lie? it's a problem for mission makers who want to add them as static objects.

(as a by-note, why is it that there isn't a single civilian aircraft in the whole game? are you trying to tell me that the kingdom of sahrani built a massive paved runway when no-one has a plane? i might be dreaming, but i'd love to see something like a civilian cargo plane placed in-game to give things a bit of flavour.)

so that's my thoughts on the subject. i really do wish BI would implement these things in a patch, but i guess we'll have to wait and see.

[Scorpio 0]

I'd really really like to know...is this move possible in real life?:

http://uk.youtube.com/watch?v=wK1F9lr4MR4

Personally I find it very hard to pilot any kind of aircraft in ArmA...in OFP it was a piece of cake. I thought at first it might just be me...but I've been trying for several days now and its still pretty iffy.

The most annoying thing is turning in a helicopter. I have to really take my time because if I bank too suddenly then the whole chopper goes upside down and I lose control...and so turning very slowly at high speed makes me end up way off course.

[wamingo 1]

I'd really really like to know...is this move possible in real life?:

http://uk.youtube.com/watch?v=wK1F9lr4MR4

The most annoying thing is turning in a helicopter. I have to really take my time because if I bank too suddenly then the whole chopper goes upside down and I lose control...and so turning very slowly at high speed makes me end up way off course.

If the cobra can do that I haven't a clue.. but this one seems able: http://uk.youtube.com/watch?v=RGu45s1_QPU&mode=related&search=

I must say I find you have to try rather hard to get it upside down... Are you using a mouse to steer? (I use mouse)

Is your sensititivty setting very high or so?

[Scorpio 0]

Actually I just hit the left/right cursor key

edit: yeh, you can use the mouse too

What do you mean about the sensitivity setting? Do you mean the mouse sensitivity in options?

edit2:

here is another video showing how it turns. Of course it turns fine when hovering but as soon as it gains speed its very flimsy. As soon as I use move the mouse a bit, the nose points down to the right and the whole thing seems to rotate about its axis, heh

[wamingo 1]

yes mouse sensitivity.

if you turn by pulling back on the mouse then it's quite easy to flip over I guess. I use backwards key for that.

[Scorpio 0]

I use backwards key for that.

Oh, you mean this?

I tried changing the mouse sensitivity...it makes very little difference.

[wamingo 1]

No. Maybe I misread when you said upside down.

I meant like, when you're turning, usually at high speeds, you roll to ~45-90 degree's and then apply backwards force so you turn faster. Like a plane. But the closer you get to 90 degrees the easier it is to accidently go over which ends you in "upside down". With a mouse it's a bit difficult to apply that force without also rolling so perhaps it would be "safer" to simply use backkey.

Sorry if I'm just stating the obvious.

[max power 21]

Many helicopters can perform all manner of aerobatics. The cobra has semi-rigid rotors so it shouldn't have a problem with them. I don't know how maneuverable it is compared to ingame, however.

[jasono 0]

Can the cobra take the G forces from doing rolls and flips like that?

[max power 21]

from what I understand, the problem with helicopters and aerobatics has little to do with g forces and more to do with aerodynamic forces causing the rotor to strike the tailboom. This isn't a concern with semi rigid rotors. Also, g forces are only as high as you wish to make them in any aerobatic maneuver. The tighter and faster, the higher the gs. So, if you want to do a relatively low g loop, it's just going to be slow and wide... and there aren't any g force concerns in a rolling motion.

[-ZG-BUZZARD 0]

I must find it strange that most people are complaining about the helicopters (yes, they're more difficult to fly than in OFP, but they're more or less bearable except for the rudder issue), but the plane flight model is so insufferable and so incongruous with all my previous flying, that I can't help but stick to helos in ArmA... and beg for a change to OFP fixed-plane flightmodel in the next patch!

[LeftSkidLow 1]

from what I understand, the problem with helicopters and aerobatics has little to do with g forces and more to do with aerodynamic forces causing the rotor to strike the tailboom. This isn't a concern with semi rigid rotors. Also, g forces are only as high as you wish to make them in any aerobatic maneuver. The tighter and faster, the higher the gs. So, if you want to do a relatively low g loop, it's just going to be slow and wide... and there aren't any g force concerns in a rolling motion.

It has to do with aerodynamics and g forces combined, specifically negative G's. Anytime a rotor disc is unloaded, below 1 and negative G's the blades tend to flap excessively which could take out the tail boom. A semi rigid is the worse possible choice for attempting to aerobatics with because not only is it susceptible to that excessive flapping in low and negative G situations, it is susceptible to mast bumping, there is no limit to how much the blades teeter in a semi rigid until they hit the rotor mast, which usually shears it 2 and separates from the helicopter. A fully articulated rotor head has a droop stop, which is basically a movable plate around the rotor mast that a drooping blade will hit before the mast. A rigid rotor head would be the most favorable in aerobatics because the blades themselves are composite and built to flex, feather, lead/lag, and flap without any hinges.

[max power 21]

-1 g is just inverted flight, I wouldn't go so far to say as that you are 'pulling negative g's' in that flight configuration... but those are the kinds of conditions that you would expect a tail boom strike... otherwise all helicopters should be able to do loops, as that is a positive g configuration all the way through, except for perhaps if you're stalling at the top... that's where I was coming from, at any rate... and I guess I was calling rigid rotors semi-rigid.