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Since I was a former Cobra pilot, and then an Apache pilot, I'll answer that..(in my dreams)That's how it attains directional motion, by pitching (swash plates up top) at certain points during the revolution. I'm sure Don will eat this post alive.
yeah, the DOT's are not going to understand what you just posted!I understand it to an extent just from spending so much time with the crew and the airframe.from what I could tell on the video, was there was some piece of equipment that was not doing what it was supposed to do????
So, in an uneducated, introspective way.......I was half correct.......lift, transonic longitudinal regressive rotational egg beat in' bacon strips have to flutter to keep flying forward without screwing into the ground or flipping over.......add twice as much metal rotating around an oil leak and its mo' better like and called a Chinook........I now know why Bobby says, "pilots"......... :o..... ;)
So, Bobby...being the calculating trained warrior NCO that you are. Take the appropriate action, Execute!
your standard grunt level CQB is just putting rounds and rounds on scary stuff till it stops scaring you!
Quote from: KensAuto on February 09, 2016, 09:09:27 PMSince I was a former Cobra pilot, and then an Apache pilot, I'll answer that..(in my dreams)That's how it attains directional motion, by pitching (swash plates up top) at certain points during the revolution. I'm sure Don will eat this post alive.Yea, you're wrong!In forward flight the rotor system has an advancing blade, the one rotating into the headwind, and a retreating blade. At, say 100 knots forward airspeed, the advancing blade is seeing 100 knots additional airspeed and the retreating blade sees one hundred less.So say the rotor blade is doing 400 knots at it's outer foot of length. Then the advancing blade sees 500 knots of relative airspeed, and the retreating sees 300 knots. To compensate, Ken was correct, the swash plate provides for cyclic feathering of the rotor blade. It tends to flatten the pitch or angle of attack of the advancing blade and really pitch up the retreating blade. That way there is a mechanical balance of lift across the rotor system. If angle of attack remained constant like in an airplane, then the advancing blade would be making a whole lot more lift than the retreating blade, so as soon as you started moving forward, like one knot, the advancing half of the system would produce more lift than the retreating half causing the advancing side to rise, thus rolling the aircraft over.So we mechanically pitch the blade up substantially, like 15 degrees in most rotor systems on the retreating side to maintain that balance. Interestingly enough lower powered helicopters are limited in forward airspeed by how much the retreating side can maintain span-wise
I'm not exactly sure what just happened here, so I'll just leave it...Or we could discuss retreating blade stall, gyroscopic procession, translating tendency, and effects of compressibility
it's amazing those things stay in the air. it's as if everything you're trying to make it do is forcing it to fall out of the sky. over compensating to the max to keep it in flight. like shooting with Kentucky windage while running backwards down the top of a train.. all while the thing falls off a bridge. hahaha
Great explanations, Don! Care to enlighten us a little more on retreating blade stall and counter-rotational torque? Whirlybirds have always fascinated me! Such complex machines, especially when compared to fixed wing aircraft.
I kinda figured that was the fact. Makes sense, since the air flow while sitting on the tarmac pretty much sucks. High bypass turbo fans have plenty of air to spare, so why not vent some of that bypass air to the cockpit? Make sense. Lay some more on us!
Quote from: cj7ox on February 22, 2016, 12:14:53 PMI kinda figured that was the fact. Makes sense, since the air flow while sitting on the tarmac pretty much sucks. High bypass turbo fans have plenty of air to spare, so why not vent some of that bypass air to the cockpit? Make sense. Lay some more on us!Not the bypass air that you breath. That is used to shove grasshoppers and sand pipers through the cowlingYou breath the tortured stuff that got cut, diced, tumbled, crushed, burned, and smashed by eight or more spinnin' vegamatics!
Quote from: Flyin6 on February 22, 2016, 12:23:42 PMQuote from: cj7ox on February 22, 2016, 12:14:53 PMI kinda figured that was the fact. Makes sense, since the air flow while sitting on the tarmac pretty much sucks. High bypass turbo fans have plenty of air to spare, so why not vent some of that bypass air to the cockpit? Make sense. Lay some more on us!Not the bypass air that you breath. That is used to shove grasshoppers and sand pipers through the cowlingYou breath the tortured stuff that got cut, diced, tumbled, crushed, burned, and smashed by eight or more spinnin' vegamatics!Hmm! That makes me wonder what kind of exhaust we're breathing. I am assuming there is some kind of scrubber before it hits the Gaspers?
So, if a sandpiper gets liquified, hows the , uh, blood and feathers keep from being inhaled downstream?..I get it...that's how we get the bird flue!!