03 July 2005

The Normal Approach

Now we'll continue our helicopter flying lesson.
Last post we were on downwind leg.........800' above the ground and hover Manifold Pressure applied.

When we can look back at a 45 degree angle at our intended point of landing, we start a descending, decelerating turn of 90 degrees......base leg.
On base leg, we hope to descend to 400 feet above the ground and slow the helicopter to 60 knots.

Continue on base leg and approach the path you took to takeoff......then make another 90 degree turn to line yourself up on your final approach course.

Now we are on final......400 feet above the ground, indicating 60 knots. When we reach a point where we can see that our angle to our intended point of landing is 10-12 degrees, (our "normal approach sight picture"), we lower the collective in order to maintain that angle to our landing spot.

From this point on, the approach is done visually, paying almost no attention to the airspeed indicator and altimeter. We maintain our angle of approach with the Collective and try to maintain "the apparent speed of a man walking briskly across the ground" with the Cyclic.

Continue to slow the helicopter as you descend, maintaining the speed of an apparent brisk walk, until the helicopter reaches five feet above the ground. At this point, bring the helicopter to a hover, maintaining hover altitude with the Collective, heading with the Pedals, and position over the ground with the Cyclic.

In my opinion, next to hovering, the normal approach is the most difficult thing to learn to do in the helicopter. To accomplish it, we must go from a relatively high power setting....cruise flight, to a relatively low power setting........descending and decelerating for landing, to the regime that requires the MOST power the helicopter uses: hovering.

Changing power settings requires coordinating the pedals, remember? So you are mighty busy during the normal approach to landing!
Students have problems with the power application/pedal coordination during the last 50 or so feet of the approach.....it takes a while to get accustomed to the big power changes that need to be made to bring the helicopter to a hover at the intended point of landing!

This is a lot to digest, I know! Oddly, hovering, which is harder to do, is easier to describe.

Students will learn to land the helicopter fairly rapidly, although at first it won't be a pretty thing to watch..........learning to make the large power changes in such a short time frame.

So there you have it........posts for learning to hover, takeoff, traffic pattern circuit, and landing.

It's a challenging task, but a satisfying one to learn.

My students almost always walk away from the first few lessons with sweaty armpits, and post-flight smiles on their faces!

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