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  1. #1

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    beginner heli pilot needs help

    Hey Guys Im hoping some of you more experienced pilots can give me some help. When I watch more experienced pilots fly a hover to landing they make a light touchdown. When I try to do the same, the touchdown is more like an uncontrolled arrival. What are the proper control inputs to make in the transition between hover and landing? I know aerodynamically the heli is in a vortex immediately before touchdown. This is my problem spot. Do I increase throttle, decrease throttle, or is the setup done before the transition to touchdown section of the flight is arrived at? Im flying an MCX 2 and a Blade 120 SR. I did say I was a beginner. Thanks

  2. #2

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    RE: beginner heli pilot needs help

    The best I can say is your caught in the rotor wash area wich for me is a very dangerous place. Since your flying micro helis there is not a whole lot you can do. With my T-rex 100 I try to come in for a landing quickly bring it to a hover above the rotor wash area and bring it down until it feels like its on that cushion of rotorwash thenas soon as your skids are level and are about to tough the landing zone kill the motor. the best i can say is landing a helicopter is nothing more than a controlled crash practice practice

  3. #3
    Rafael23cc's Avatar
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    RE: beginner heli pilot needs help

    Since those are fixed pitch helicopters, there is not much you can do except what has ben mentioned before, practice, practice. Don't let the helicopter fall, fly it down to the landing spot.

    You could try to come in low while still flying forward. That will keep the turbulence behind you and not allow time for the vortex to form. The longer you stay hovering on one spot, the stronger the vortex will become.

    Otherwise, when you transition to collective pitch, you will see less of this effect as you allow the power of the rotor to remain fairly constant, and only change the angle of attach of the blades. The vortex will still be there, but the control on the helicopter's descent will be much more controllable.

    Rafael
    Keep your eyes on the sky but your feet on the ground!
    Team Heliproz.com / AMA # 8109

  4. #4
    Rafael23cc's Avatar
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    RE: beginner heli pilot needs help

    Oops, double post. Sorry.
    Keep your eyes on the sky but your feet on the ground!
    Team Heliproz.com / AMA # 8109

  5. #5

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    RE: beginner heli pilot needs help

    Thanks for the information guys. Looks like I need to practice more. YIPPEE

  6. #6

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    RE: beginner heli pilot needs help

    Very Good point about the low forward flight keeping the vortex behind you didnt even think about that!!!!!

  7. #7
    ArtW's Avatar
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    RE: beginner heli pilot needs help

    There are three very separate issues that you are confusing. The first is the thrust from the rotor necessary to hovering is greater than that for forward flight. In forward flight there is transitional lift from air coming into the rotor plane from I front of the heli. When one stops to hover additional lift is necessary from that level for forward flight. You must either increase rotor speed in a fixed pitch heli which takes time secondary to the inertia of the rotor head or increase pitch in a collective pitch heli. The second issue is ground effect. When you are within one rotor diameter of the ground there is increased lift from the back pressure of the rotor wash hitting the ground. So less lift is necessary as you hover within one rotor diameter of the ground than at higher altitudes. The third issue is the ring vortex state. If you descend vertically through your roter wash at more than 500 feet per minute in a full sized heli or some speed in an RC you can force air to recirculate and decrease lift. This also happens when you try to hover or land in an enclosed space like a walled court yard. The heli that crashed in Abattabod likely had ring vortex state loss of lift trying to descend rapidly into a walled compound. They had practiced with walls that were permeable (cyclone fence) and then had ring vortex when the walls were solid. So you must separate these effects when thinking of how to decelerate to hover prior to landing. In full size helis there are weight loadings and altitude/temperature situations where they can't hover prior to landing and must land with forward velocity to take advantage of the transitional lift. What you need to practice is slowing to a hover prior to decent to allow the fixed pitch rotor time to speed up so you can hover in ground effect. Then slow the rotor speed to land.

  8. #8

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    RE: beginner heli pilot needs help

    Very well put!!!!!!!!!!!!!!!!!!!!!
    ORIGINAL: ArtW

    There are three very separate issues that you are confusing. The first is the thrust from the rotor necessary to hovering is greater than that for forward flight. In forward flight there is transitional lift from air coming into the rotor plane from I front of the heli. When one stops to hover additional lift is necessary from that level for forward flight. You must either increase rotor speed in a fixed pitch heli which takes time secondary to the inertia of the rotor head or increase pitch in a collective pitch heli. The second issue is ground effect. When you are within one rotor diameter of the ground there is increased lift from the back pressure of the rotor wash hitting the ground. So less lift is necessary as you hover within one rotor diameter of the ground than at higher altitudes. The third issue is the ring vortex state. If you descend vertically through your roter wash at more than 500 feet per minute in a full sized heli or some speed in an RC you can force air to recirculate and decrease lift. This also happens when you try to hover or land in an enclosed space like a walled court yard. The heli that crashed in Abattabod likely had ring vortex state loss of lift trying to descend rapidly into a walled compound. They had practiced with walls that were permeable (cyclone fence) and then had ring vortex when the walls were solid. So you must separate these effects when thinking of how to decelerate to hover prior to landing. In full size helis there are weight loadings and altitude/temperature situations where they can't hover prior to landing and must land with forward velocity to take advantage of the transitional lift. What you need to practice is slowing to a hover prior to decent to allow the fixed pitch rotor time to speed up so you can hover in ground effect. Then slow the rotor speed to land.


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