Hovering
The defining characteristic of a helicopter is its ability to hover at any point during a flight. According to How Stuff Works, to achieve hovering, a pilot must maintain the aircraft in nearly motionless flight over a reference point at a constant altitude and on a heading (the direction that the front of the helicopter is pointing). This may sound easy, but it requires tremendous experience and skill.
In order to hover, a helicopter must be producing enough lift in its main rotor blades to equal the weight of the aircraft.
The engine of the helicopter must be producing enough power to drive the main rotor, and also to drive whatever type of anti-torque system is being used.
The ability of a helicopter to hover is affected by many things, including whether or not it is in ground effect, the density altitude of the air, the available power from the engine, and how heavily loaded it is.
How long can a helicopter hover in place?
‘When the Navy stationed me at the US Naval Air Facility called Atsugi Kaigun Kichi in 1979, the Japanese Maritime Self Defense Force [Japanese Navy] shared the base with us,’ Michael Alapaki, former US Navy enlisted aircrew who served aboard 5 carriers, recalls on Quora.
‘Every day, the Japanese helicopter rescue squadron put a ship in the middle of the airfield, it lifted up about 20–30 feet, and sat there, hovering from breakfast to lunch, and then again for the whole afternoon.
‘Didn’t matter what the wind was doing. That chopper hovered in place, all day long. For practice, I guess.’
Alapaki continues;
‘While I was stationed in Japan, I decided to train for a private pilot certificate, and I flew little Cessna’s.
‘One of the final tests was to fly solo, by myself, on a long cross-country flight over 200 miles, and land at several airfields.
‘An hour into the flight, concerned about my fuel state, I lined up to land at a Japanese helicopter base called UTSONOMIYA.
Half the Japan Ground Self-Defense Force choppers hovering
‘When I looked straight ahead to the runway, this was what I saw.
‘Musta been half the JN army [Japan Ground Self-Defense Force AKA Japanese Army] choppers hovering over the field I needed to land on. CRAP! Pucker factor 9.
‘So I made sure they knew I was coming, eyeballed a thread-the-needle route between the choppers to the runway, and held my breath.
‘I landed, got a signature proving I was there, and took off for the rest of my cross country, soon to be over water, to land on a tiny dot just at the inside edge of my fuel reserve.’
Alapaki concludes;
‘Those Japanese choppers hovered all day, just for fun. The kind of fun you only get in the military.’
Photo by Derek Webster / U.S. Navy, U.S. Army and Japan Self-Defense Forces