Basic Helo flying info
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When you do a cyclic pushover, the nose goes down and the tail goes up. This puts the tail rotor’s thrust “line” above the CG – so the thrust rolls the helicopter. This is really only an issue with a 2-bladed rotor like the Bell 207, Huey, R.22, R.44 and so on.
And I think I get the low RPM thing too now. I think what I was forgetting was that the R22 usually operates with excess power available. So say the pilot pulls on the collective ( increases pitch of blades, more drag, larger lift) the rotor RPM would normally go down. So the governor asks the engine to provide more manifold pressure, and since it has excess MP, it brings back the RPM to nomial. So now, you got higher pitch for same RPM...thus more lift...and the helicopter climbs.
Now where the trick is...is when you reach the limit of this excess engine power.
Say you are closer to the limit...and you pull on the collective (same stuff, higher drag, more lift) so lower RPM , and the governor asks the engine for more power to keep the RPM up. Well, in this case there is no excess power, so the engine CAN'T maintain rotor RPM, and thus it goes below 104% (the optimal...for lowest drag etc).
Well, if the pilot requires excessive collective, and the engine is at it's limit...then obviously the RRPM is going to plummet...and you are going to have an extremely low RRPM...that might not be enough for autorotation...thus you are screwed.
That's my understanding at the moment, which seems to make sense to me from a technical standpoint.
Archer
Archer, when the pilot demands more power (by raising the collective) than the engine can produce, the RRPM will decay - this is called "Overpitching" and should be demonstrated to all helicopter pilots. Don't worry about autorotation in this scenario, as soon as the lever is lowered, the engine will be able to cope again and the Nr will return to normal.
As for hovering - the key is in maintaining the correct hover attitude (a bit nose up and a bit left skid low for an R22). The required attitude will change depending on wind speed (more nose down to maintain position over the ground as the wind increases) and C of G (both lateral and fore and aft). As a plankie pilot you will tend to want to put the wings level - this will cause the helicopter to drift to the right quite quickly.
You should get given one control at a time - usually cyclic first to sort out the hover attitude, then the collective and last the pedals. It is best to then combine 2 controls (cyclic and collective or collective and pedals) before going for all 3 together. You have to learn to be logical and identify which control will correct the error you see in front of you. Unfortunately a helicopter will want to drift, yaw and climb all at the same time which is why it takes a while to be able to hover well.
Good luck and enjoy it.
As for hovering - the key is in maintaining the correct hover attitude (a bit nose up and a bit left skid low for an R22). The required attitude will change depending on wind speed (more nose down to maintain position over the ground as the wind increases) and C of G (both lateral and fore and aft). As a plankie pilot you will tend to want to put the wings level - this will cause the helicopter to drift to the right quite quickly.
You should get given one control at a time - usually cyclic first to sort out the hover attitude, then the collective and last the pedals. It is best to then combine 2 controls (cyclic and collective or collective and pedals) before going for all 3 together. You have to learn to be logical and identify which control will correct the error you see in front of you. Unfortunately a helicopter will want to drift, yaw and climb all at the same time which is why it takes a while to be able to hover well.
Good luck and enjoy it.
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well, it's not happening today as I had wished...weather is IFR still.
Yeah I read about the fact that helicopters will touch down on one wheel or skid first...since to counter the side force during hover a pilot must bank/move the cyclic to the left to maintain position and hover.
I understand this since that's exactly how you touch down with an airplane in a x-wind landing...one main gear, then the other, then the nose gear...due to the wind which imparts a side force on the aircraft that you have to counter by banking.
Same thing with a helicopter I gather...except the side force is produced by the tail rotor...which is producing thrust in one direction and thus needs to be countered...
Archer
Yeah I read about the fact that helicopters will touch down on one wheel or skid first...since to counter the side force during hover a pilot must bank/move the cyclic to the left to maintain position and hover.
I understand this since that's exactly how you touch down with an airplane in a x-wind landing...one main gear, then the other, then the nose gear...due to the wind which imparts a side force on the aircraft that you have to counter by banking.
Same thing with a helicopter I gather...except the side force is produced by the tail rotor...which is producing thrust in one direction and thus needs to be countered...
Archer
Helicopter Pilots Get It Up Quicker
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Whirlygig ...
I had same problem after I passed my private checkride - fortunately the examiner wasn't watching!
Oh and I ve a couple of hundred hrs, including time in the 206 - not much I know - but I ve never managed to fly it in MS Flightsim....
I can't get Heliport's first link to work...
Anyone else having problems?
PW
I had same problem after I passed my private checkride - fortunately the examiner wasn't watching!
Oh and I ve a couple of hundred hrs, including time in the 206 - not much I know - but I ve never managed to fly it in MS Flightsim....
I can't get Heliport's first link to work...
Anyone else having problems?
PW
