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Landing from a Hover

This maneuver is used to transition the helicopter from a hover to a landing on the ground.

Maneuver Description

From a normal hover, decrease power to approach the ground. Inexperienced pilots should avoid the normal tendance to look directly in front of the helicopter. Better results will be obtained if you either look up at the horizon, or halfway between the ground in front of the helicopter and the horizon (normally this would be a spot 50-100 feet in front of the helicopter). It is critical to be aware of the horizon, and looking too close to the helicopter removes this from your vision.

You don't normally need to look down to judge your height above the ground. Your peripheral vision will do this for you. When the ground seems to be about level with your ears, you're about to touch down. When landing on an elevated platform, your peripheral vision may not give you this feedback, and you may have to glance down to judge altitude. The trick is not to stare down, but to just take quick looks to monitor your progress toward the ground.

As you descend, ground effect will decrease your descent rate, and you will have to continue to lower collective to maintain a steady descent rate. As you are approaching the ground, allow ground effect to decrease your descent rate for a softer touchdown. Don't allow your descent rate to stop, however. You don't want to wallow around at a low skid height. Make sure you continue to descend toward the ground.

Eventually a skid is going to touch the ground. If the helicopter is not hovering perfectly level, this will cause the helicopter to pitch, roll, or both as the fuselage transitions from hover attitude to the attitude it assumes sitting on the skids. As it pitches and rolls, input opposite cyclic just as you would on a slope landing, in order to prevent drift.

Many pilots will quickly get the collective down in order to get weight on the skids, as this will stop any sliding motion. This is a bad technique for a couple reasons. One, if the ground isn't level enough, the helicopter could roll over (I've landed in tall grass that makes it impossible to see the ground - one time there was a hole under the rear of one of the skids. The helicopter started to tip over backward, but the fact that we were slowly decreasing collective gave us plenty of time to abort the landing and find a different spot to land on). Another bad thing about lowering collective too quickly is that you are rapidly lowering the blades toward the fuselage, and you increase the chance of rotor to airframe contact on a gusty day.

The better technique is almost the reverse of the technique I described in Takeoff to a Hover. Hover slowly down until a skid touches. Balance there for a few seconds without allowing the helicopter to drift around on the ground. Lower some more collective and put a little more skid on the ground, while compensating for drift. Keep doing this a stage at a time until you have slowly lowered the helicopter all the way onto the ground. Practicing this will allow you to land accurately every time.

Typical Mistakes

Going for it!

A very common mistake is for pilots to descend until they estimate they are almost on the ground, and then rapidly lower collective. It's the reaction to the feeling "I just want to be on the ground". There are multiple problems, the most typical being that sometimes you are higher than you think you are, and you can get a fairly hard landing if you just lower a lot of collective. Advice: descend until you think you are close to the ground. Continue to descend at a slow rate until you feel a skid touch. Continue to slowly lower collective, while making cyclic pitch adjustments for any pitch and roll necessary to get onto the skids.

Overcontrolling near the ground

Lots of pilots start to over control when they are near the ground. A pilot who is holding a good hover will suddenly start wobbling all over as he gets near the ground. The problem is that people get concious of the ground, and want to have a perfect hover in preparation for landing. Just hold the best hover you can during the descent, and don't make any special efforts as you touch down. Unless you are really bad at hovering, this will give you a safer landing.

Not countering pitch and roll

Some pilots never learn to use the cyclic to counter pitch and roll during the transition onto the skids. The result is sliding around on the parking space, which is dangerous. Go out and practice your slope landings, both parallel to the hill, and facing uphill (watch your tailrotor!) and you'll be practicing the same elements required for landing on level ground. My observation is that every takeoff and landing, even from a level area, is really a slope takeoff and landing because of CG causing roll and pitch.

Landing next to another helicopter at low RPM

A pet peeve of mine. Helicopters are susceptible to rotor->airframe contact while they are at low rotor RPM. They are at low rotor RPM during startup and shutdown. Therefore, don't land next to a helicopter that is just starting up, or has just shut down with it's blades still turning. If you are about to pick up to a hover, don't do it if the pilot in the next aircraft over is about to enage his rotors or has just killed his engine. Wait until the other aircraft's rotors are either stopped, or are up to operating RPM before you subject that aircraft to your downwash.

Proper orientation to land with respect to wind direction

Although it is certainly easier to land pointed into the wind, if the wind is really strong or gusty you increase the chance of a tailboom strike during shutdown or subsequent start up by landing into the wind. The problem is that the rotor blade is flapping down and reaches maximum downward deflection when it is over the tailboom when you land pointed into the wind. Instead, if you either land tail into the wind (not such a hot idea for a turbine aircraft) or with a cross wind, the blades will not be at maximum down flap as they pass over the tailboom. Some manufacturers recommend having the wind at your 7-8 o'clock position in this situation.

If you are an inexperienced pilot, you might not want to attempt tail into the wind takeoffs and landings, since they are slightly more difficult to perform. Hopefully an inexperienced pilot won't be flying on days where the wind is strong enough to make boom strikes a concern..

Paul Cantrell
paul at copters.com (replace " at " with "@" to email me - this avoids SPAMMERS I hope)

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