Raven Morpheus Posted August 13, 2014 Posted August 13, 2014 Hello Not criticising the FM or anything, but I've just seen this video of a UH-1H starting up and taking off and it has me wondering something - Every time I startup my UH-1H (admittedly through the auto start cheat) I get a little chickendance where the UH-1H will rock side to side on the skids whilst the rotors start spinning up. So, why does the UH-1H do that little chickendance when in real life it doesn't appear to?
Grim_Smiles Posted August 13, 2014 Posted August 13, 2014 The devs have sometimes made vibrations and other things on the sims much more pronounced in visual movement than they are in real life to give a simmer feedback on what the aircraft is doing, since we can't feel vibration through a sim. This may be one of those instances where the developer exaggerated the movements of the chopper to give that engine startup feedback while someone is staring at the instruments. Just a guess on my part but I'm betting this is why they did that. "Hurled headlong flaming from the ethereal sky; With hideous ruin and combustion down; To bottomless perdition, there to dwell; In adamantine chains and penal fire" (RIG info is outdated, will update at some point) i5 @3.7GHz (OC to 4.1), 16GB DDR3, Nvidia GTX 970 4GB, TrackIR 5 & TrackClip Pro, TM Warthog HOTAS, VKB T-Rudder Mk.IV, Razer Blackshark Headset, Obutto Ozone
SmukY Posted August 13, 2014 Posted August 13, 2014 (edited) It does the 'chickendance', you just have to pay attention and it's not that much visible because of poor quality of video. here is more noticeable: edit: Oh and yeah, ED may exaggerated it ... a little. edit2: found another video of japanese ah-1s edit3: ok now I'm exaggerating too lol ... Huey's chickendance is nothing in comparison of this American civilian Mi-24 Edited August 13, 2014 by SmukY Helicopters don't fly, they just subdue the air. [sIGPIC][/sIGPIC]
Raven Morpheus Posted August 13, 2014 Author Posted August 13, 2014 Yeah I can just about see the AH-1 wobbling, but your UH-1 vid I can't see it in. The in-game UH-1H hops from side to side as though it's skids are hot as soon as the rotors spin up, on a hard standing FARP at least, I actually haven't checked on grass because you don't tend to start a mission from the grass. Definitely see it in the Mi-24 though. TooTalls reasoning makes sense I guess, I just thought having watched the videos I've seen of UH-1H starting up that it's slightly odd/unrealistic behaviour. Oh, well, c'est la vie.
sondo214 Posted August 13, 2014 Posted August 13, 2014 Would be nice if the chickendance could be felt in FF joysticks too...
ericoh Posted August 13, 2014 Posted August 13, 2014 The chickendance is the best thing about the huey! It makes it feel like theres actualy something happening. Alot of sim aircraft are rather boring on that part.
doveman Posted August 14, 2014 Posted August 14, 2014 I don't think there's any place in a sim for unrealistic aerodynamics/aircraft modelling, so if this is unrealistic I think it should be taken out. You could use a camera shake effect to give the impression of vibration instead perhaps. Main rig: i5-4670k @4.4Ghz, Asus Z97-A, Scythe Kotetsu HSF, 32GB Kingston Savage 2400Mhz DDR3, 1070ti, Win 10 x64, Samsung Evo 256GB SSD (OS & Data), OCZ 480GB SSD (Games), WD 2TB and WD 3TB HDDs, 1920x1200 Dell U2412M, 1920x1080 Dell P2314T touchscreen
jimcarrel Posted August 14, 2014 Posted August 14, 2014 Yeah, the chicken dance thing has really put me off LOL (sarcasm) Win 10 64 bit Intel I-7 7700K 32GB Ram Nvidia Geforce GTX 1060 6gig
ericoh Posted August 14, 2014 Posted August 14, 2014 (edited) Watch her chickendance. Edited August 14, 2014 by ericoh
b00ce Posted August 14, 2014 Posted August 14, 2014 All helicopters do this on start up, its awesome sitting in a blackhawk on a run up. LG 34UC97 34" 3440x1440 monitor | 2x GTX-980 G1 Gaming I7-5820k @ 3.3GHz | 16GB Corsair Vengeance DDR4 @ 2133Mhz Samsung 840 EVO 120GB & 1TB SSDs | Seagate 3TB HDD TM Warthog | Saitek Pro Flight Combat Pedals
doveman Posted August 14, 2014 Posted August 14, 2014 All helicopters do this on start up, its awesome sitting in a blackhawk on a run up. Well if it's realistic then of course it should be happening. Now I'm upset it doesn't happen with the ka-50 Sort of joking but when an aircraft in the sim behaves differently to how it does IRL it makes me worry about what else might be modelled poorly or not at all. Main rig: i5-4670k @4.4Ghz, Asus Z97-A, Scythe Kotetsu HSF, 32GB Kingston Savage 2400Mhz DDR3, 1070ti, Win 10 x64, Samsung Evo 256GB SSD (OS & Data), OCZ 480GB SSD (Games), WD 2TB and WD 3TB HDDs, 1920x1200 Dell U2412M, 1920x1080 Dell P2314T touchscreen
Phantom453 Posted August 14, 2014 Posted August 14, 2014 IMHO is seems okay from within the Huey cockpit during startup, but when you watch it form outside in F2 view, the same thing seems far too pronounced.
Devrim Posted August 14, 2014 Posted August 14, 2014 If you want to see exaggeration, watch Huey from F2 in a multiplayer session. :) Intel i7-14700@5.6GHz | MSI RTX4080 SuperSuprimX | Corsair V. 64GB@6400MHz. | Samsung 1TB 990 PRO SSD (Win10Homex64) Samsung G5 32" + Samsung 18" + 2x8"TFT Displays | TM Warthog Stick w/AVA Base | VPC MongoosT-50CM3 Throttle | TM MFD Cougars | Logitech G13, G230, G510, PZ55 & Farming Sim Panel | TIR5 & M.Quest3 VR >>MY MODS<< | Discord: Devrim#1068
Flagrum Posted August 14, 2014 Posted August 14, 2014 (edited) Well if it's realistic then of course it should be happening. Now I'm upset it doesn't happen with the ka-50 Sort of joking but when an aircraft in the sim behaves differently to how it does IRL it makes me worry about what else might be modelled poorly or not at all. I am not even sure why it happens at all. I mean, the rotor is always balanced - weight wise. So it can not be the cause for the rocking of the fuselage, right? But IF ... then regarding the Ka-50 ... as a coaxial rotor, this inbalance is perhaps automatically compensated by the counter rotating rotors? edit: or is it because when spinning up the rotor, the rotor disc is not parallel to the ground/fuselage? One side further up, the other further down ... and while spinning this angle moves around the helo, so to say. And the higher up blade causes some sort of "leverage" effect? God, I hate that I have no clue about physics and engineering ... Edited August 14, 2014 by Flagrum
ericoh Posted August 14, 2014 Posted August 14, 2014 I think you're right. The blades are simply not 100% aligned till they reach enought velocity.
Hueyman Posted August 14, 2014 Posted August 14, 2014 Absolutely. This is what happen on a fully articulated rotor system like on the Mi-8 and this SA330 Puma for example. You can see the blade grips rotate around 3 axis : lead/lag, flap and it's own axis for pitch change. In the lead/lag axis, it make the whole assembly looks like this when nothing is spinning : Because it rotated around this axis : And at start up, this is causing this : Exactly the same thing you see on this Mi-24 start up. As the rotor spools up, angle between all blades become more or less equal ( lead/lag dampers take care of that now ) and the shakes vanishes. On the semi-rigid head design of the Huey, it's different but not so much after all. Blades are always aligned ( only damped by the blade grip drag brace ) but at some RPM during spool up, the dynamic balancing isn't correct and it produces this effect. But IRL it will never rock from one skid to another like it does in DCS, the whole rotor assembly shakes around main gearbox, and itself shakes around the whole mechanic which is mounted on the airframe which, finally, absorb the twist stresses and finishes in the landing skid struts. In DCS, it would be a nightmare to calculate every stresses on every part of the airframe to realistically simulate that shake, so it is simple to make the whole helicopter rocks on the ground at those RPM... By the way, I remember seeing the Belsimtek Mi-8 doing exactly what the Mi-24 on your video did : even though it wasn't visually noticeable ( as rotorhead animation isn't finished at all on the Beta Mi-8 ), we could see the whole heli slowly shaking on it's landing gear shock absorbers while the blades got lined up, that was pretty neat to see, because all other animations ( shock absorbers, landing gear, etc ... ) are spot on ! [sIGPIC][/sIGPIC] CPL(A)IR ME/SEP/MEP/SET - CPL(H)
aeliusg Posted August 15, 2014 Posted August 15, 2014 Well if it's realistic then of course it should be happening. Now I'm upset it doesn't happen with the ka-50 Sort of joking but when an aircraft in the sim behaves differently to how it does IRL it makes me worry about what else might be modelled poorly or not at all. EGT? :cry:
Rabbit_ Posted August 15, 2014 Posted August 15, 2014 I am not even sure why it happens at all. I mean, the rotor is always balanced - weight wise. So it can not be the cause for the rocking of the fuselage, right? But IF ... then regarding the Ka-50 ... as a coaxial rotor, this inbalance is perhaps automatically compensated by the counter rotating rotors? edit: or is it because when spinning up the rotor, the rotor disc is not parallel to the ground/fuselage? One side further up, the other further down ... and while spinning this angle moves around the helo, so to say. And the higher up blade causes some sort of "leverage" effect? God, I hate that I have no clue about physics and engineering ... True.
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