Lowering collective while running on
Joined: Jun 2002
Posts: 352
Likes: 0
From: Andover, Hampshire
FRW, use throttle to control heading during power run-on landing. In the event that you have one of the unluckiest days in your life and your pedals jam during a donkey stop then take all your forward speed off during the flare and accept the inevitable rotation during the "check" phase of the manoeuvre. Minimise effects by prudent use of the wind.
Joined: Jan 2004
Posts: 38
Likes: 0
From: Florida
TFS
I am presuming that you are still talking about an autorotative landing rather than a run on landing with power.
Once the engine is no longer driving the rotor, there is no torque reaction. In fact, quite the opposite, there is a dragging effect of the main rotor trying to drag the fuselage around with it. This has the effect of changing the "power pedal". For example, in powered flight in lets say, a 206, the power pedal is the one on the left. Under power, if this pedal is pressed it will increase the power requirement. In an eol, if the right pedal is pressed, it will sap precious inertia(power) from the main rotor. Therefore, you could find yourself in an eol touchdown with an adverse wind, using the right pedal to keep the aircraft straight and end up running out of pedal as the rrpm decays to a level which no longer allows tail rotor authority.
Another factor to include whilst considering using the collective as a brake!!
I am presuming that you are still talking about an autorotative landing rather than a run on landing with power.
Once the engine is no longer driving the rotor, there is no torque reaction. In fact, quite the opposite, there is a dragging effect of the main rotor trying to drag the fuselage around with it. This has the effect of changing the "power pedal". For example, in powered flight in lets say, a 206, the power pedal is the one on the left. Under power, if this pedal is pressed it will increase the power requirement. In an eol, if the right pedal is pressed, it will sap precious inertia(power) from the main rotor. Therefore, you could find yourself in an eol touchdown with an adverse wind, using the right pedal to keep the aircraft straight and end up running out of pedal as the rrpm decays to a level which no longer allows tail rotor authority.
Another factor to include whilst considering using the collective as a brake!!
Joined: Mar 2005
Posts: 1,289
Likes: 289
From: Poplar Grove, IL, USA
I've only ever done one of these, but I'll open my mouth anyway. I was doing touchdown autos as a student, and I blew it. Was going to end up in the pit at the north end of the runway on the wrong side of the fence. The instructor told me to flare over the pit, hold 60, and milk the collective to clear the fence and touch down at 60. As I touched down, I could see the sparks flying in the chin bubble windows. It sounded really bad. I had no desire to drop the collective and grind it out any worse. The last 5 feet were really ugly as it finally ground to a halt. I leaned out the door and looked back, amused to see two smoke trails rising from the runway like something out of a roadrunner cartoon. The aircraft was an Enstrom F28A.
-- IFMU
-- IFMU
