Why would a helicopter need to fly upside down? The rotor head the bit that connects the blades to the engine and controls the helicopter is only designed to work in normal attitudes. Peter Elliott, St Albans UK Model helicopters can certainly fly upside down, because their collective pitch control allows the rotors to be negatively pitched.
That is, to direct air flow "up" relative to the fuselage instead of "down". While it is theoretically possible to do this on a full-sized helicopter, it would be a brave pilot indeed to tried it. Simon Blake, Shrewsbury England In theory yes. But not sustained flight. A helicopter with sufficient speed and power could fly a loop without problem.
I think this trick is done at air shows sometimes. Flying in a straight line upside down would not work though. Meredydd Wilson, Cincinnati, USA They indeed can, and looping the loop is a common action in higher powered helicopters. As long as the head can move the rotors the right way, then they could produce enough lift to fly horizontally upside down. David Roberts, Crewe I am not aware of any full-size helicopters that are built so that they can fly upside down. However, it is certainly possible and model helicopters are flown upside down all the time.
All that is required is to have the pitch of the main and tail rotors adjustable to the point where they begin to blow air in the opposite direction to that which they do usually. Michael Fisher, Brisbane, Australia I must take issue with the first sentence of the previous answer.
It is quite right that if a helicopter is upside down with its rotors moving, it will be moving downwards. So, the answer is "yes, albeit briefly". Chris Thornton, Stirling, Scotland Yes - if they put the rotor at the bottom. Older machines did not have the power or the rotor technology to make rolls a safe aerobatic option.
Glyn Baker, S Ockendon U. K Yes. It is, just, possible to loop a full sized helicopter, but the torque involved makes the manoeuvre difficult and extremely dangerous, as well as pointless. Remote control helicopters, where pilot safety is less of a concern, can and often are fitted with full-range collective swash-plates, which allows a skilled pilot to hover the model inverted.
Simon Blake, Shrewsbury, England In theory, if the collective pitch mechanism were altered to enable negative lift in the normal orientation, then the helicopter could fly upside down. Ask Question. Asked 1 year, 8 months ago. Active 1 year, 8 months ago. Viewed times. Improve this question. QuIcKmAtHs 3, 4 4 gold badges 14 14 silver badges 35 35 bronze badges. In the case of a helicopter rotor, the mechanism is designed to respond almost instantly to control inputs. A flight instructor once told me, "Wings work by beating the air down.
Bernoulli just explains why some wing shapes do it more efficiently than others. Add a comment. Active Oldest Votes. Improve this answer. Plus, you can fly the helicopter in a loop or roll where the rotor is loaded all the time.
It's no different from the same maneuver in an airplane where you can hold a cup of coffee without spilling, even though in mid-maneuver it is upside-down. One time, he tells me, he almost killed himself trying to perform under similar conditions. This gives me pause, but Aaron assures me that we'll be fine if we go out over the water and try a few maneuvers. So up we go. We launch from the Naval Air Station's ramp and pass over the beach. Aaron climbs until he's above the barrier island that he'll use as a reference line to orient himself.
Then he pulls up into the loop. In a matter of seconds we're over the top, then arcing downward. Aaron has discovered that this can be the most dangerous part. That doesn't happen today, I'm pleased to report. Aaron once again pulls up into a climb, then startles me by rolling over to the left until our bodies are parallel to the horizon. He keeps rolling until we're upside down, then brings us back up the other side.
In a plane, the equivalent maneuver would be a mild trick called an aileron roll; in a helicopter, the procedure causes a disconcerting sensation, as if someone were holding you by your heels over the edge of a tall building. Next, Aaron pulls back on the stick and waits for his airspeed to bleed off until we're nearly dead in the air.
Then he pushes the stick forward. A second later we're toppling forward. As we fall straight down Aaron rotates us degrees on a vertical axis so our track is like the stripe on a barber pole, then pulls back so we level out.
Aaron keeps stringing together one maneuver after another: up, sideways, down— whoop! I'm starting to think about a barf bag as Aaron pulls out of a climb and turns us into the wind.
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