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Had a dissagreement with a bloke the other day bout the limitaitons on teetering and when you get there.[?]Usualy i'd just tell him to restudy the concept of teetering coz i recon my understanding is right, but this bloke is sumone i hold in the highest regard coz of his abilities. I know he's very switched on coz i'v had a bit to do with his handywork, and he couldn't do wot he dose without knowlage and understanding of the principals of gyros.I must add tho that the dissagreement we had had nuthn to do with his feild of experties. All the same, his differing understading on this subject has sowen seeds of dout bout my own understanding. My understanding of the reason for the teetering hinge, and how it works you must understand, cums from the logical[ and sumtimes flawed] thinking process of a SGC.[
]But heres my understanding.The hinge's main task is to allow the equalising of lift of the two opposing blades when they have different ASs.In a true virtical decent, both blades are seeing the same AS and AOA all round the disc, so theres no need for the hinge coz the lift is equal round the disc.Add some forward movement to the machine/disc and the advancing blade see's higher AS [ blade's rotational speed + forward speed] and the retreating blade see's less AS[ rotational speed - forward speed]. This differential in each blades AS on opposing sides of the disc is going to cause a differential in lift, and try to roll the disc/machine The teetering hinge allows the blade with the higher AS/lift to rise, which allows the other blade, which has less AS/lift to drop. This equalises each blades AOA/lift with no change in the driection of the sum of lift of the two blades, so lift remains parralell to the rotor bearing bolt. [ up IOW]Now, the dissagreement was "when do you reach a point when you run out of teetering". IOW, when will the hub bar start to touch the stoppers[ teetering limit] in S/L flight, if theres inadiquate teetering room?Thinkn logical, like a SCG dose, i recon its at the highest speed.If theres no teetering action in a VD, and teetering increases with increased forward AS, then logicaly the limiters will be touched at the highest speed. Or the VNE of a machine with inadiquate teetering room, is when the bar starts to touch the stoppers.Remember, im only refering to S/L flight.Like i said, im a SCG, and i'v been known to be wrong before.[
]Note; i like to know these things coz i recon, till you understand fully the physics and general working of a machine, any machine, then you can't get the maximum performace out of it............. without going past its/ your limits. [}
]Ignorance is bliss............but only till you realise you were.birdy, here.
]But heres my understanding.The hinge's main task is to allow the equalising of lift of the two opposing blades when they have different ASs.In a true virtical decent, both blades are seeing the same AS and AOA all round the disc, so theres no need for the hinge coz the lift is equal round the disc.Add some forward movement to the machine/disc and the advancing blade see's higher AS [ blade's rotational speed + forward speed] and the retreating blade see's less AS[ rotational speed - forward speed]. This differential in each blades AS on opposing sides of the disc is going to cause a differential in lift, and try to roll the disc/machine The teetering hinge allows the blade with the higher AS/lift to rise, which allows the other blade, which has less AS/lift to drop. This equalises each blades AOA/lift with no change in the driection of the sum of lift of the two blades, so lift remains parralell to the rotor bearing bolt. [ up IOW]Now, the dissagreement was "when do you reach a point when you run out of teetering". IOW, when will the hub bar start to touch the stoppers[ teetering limit] in S/L flight, if theres inadiquate teetering room?Thinkn logical, like a SCG dose, i recon its at the highest speed.If theres no teetering action in a VD, and teetering increases with increased forward AS, then logicaly the limiters will be touched at the highest speed. Or the VNE of a machine with inadiquate teetering room, is when the bar starts to touch the stoppers.Remember, im only refering to S/L flight.Like i said, im a SCG, and i'v been known to be wrong before.[]Note; i like to know these things coz i recon, till you understand fully the physics and general working of a machine, any machine, then you can't get the maximum performace out of it............. without going past its/ your limits. [}]Ignorance is bliss............but only till you realise you were.birdy, here.
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