Landing a helicopter from the hover is not easy. An experienced instructor explains how it is done. Readers may want to first take a look at How Do Helicopters Fly, and also How to Take Off in a Helicopter.
Come to a Controlled Hover
The pilot should first come to a controlled hover, about two to four feet above the ground. He or she should face the helicopter into wind if at all possible, as this will make landing easier, then relax on he controls and look well ahead.
Hovering Lower and Lower Until the Ground is Reached
The pilot then simply hovers lower and lower, keeping the helicopter well under control. He should not allow any sideways drift, but should continue, not actually trying to land, until the helicopter touches the ground. He should then gently lower the collective.
Possible Mistakes When Trying to Land
The most likely mistake is allowing the helicopter to drift sideways. This must be prevented, as if one skid touches down first, dynamic rollover is possible. This is when the helicopter acts about a pivot point – the skid, and it can then turn over. Dynamic Rollover is less likely when landing than when taking off, as less power is applied. But it is still possible, so sideways movement should be definitely avoided. If the hover is not steady, the pilot should raise the collective a little and try again.
The ‘Ground Cushion’ or ‘Ground Effect’
As the helicopter sinks, the air underneath it will collect, forming a cushion of air under the aircraft. This is known as the ‘Ground Cushion’ or ‘Ground Effect’. It can be difficult to push the helicopter through this cushion of air; instead, the aircraft seems to kind of slide over it. Sometimes a fairly definite, though gentle, downward movement of the collective is required, in order to push through the ground cushion. This is most likely when landing on asphalt or concrete; on grass surfaces the air cushion is weaker and less likely to be a problem. For this reason students usually learn first to land on grass. When they try on a hard surface, their instructors will often spend some time telling them to ‘push through ground effect’.
Once the helicopter is actually on the ground, the collective should be firmly lowered as far as it will go. The pilot is then ready to shut down the helicopter in the usual fashion.
For further information on how to fly helicopters, take a look at:
Further Reading
The Helicopter Pilot’s Companion, by Helen Krasner, Crowood Press 2008
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