Why do plane and helicopter pilots have to pysically fight with their control stick when flying and something goes wrong?

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Why do plane and helicopter pilots have to pysically fight with their control stick when flying and something goes wrong?

In: Engineering

The controls are often (especially in older aircraft designs) physically linked to the control surfaces by steel cables. If the force of air is pushing on the ailerons/elevator/rudder it’s also moving the stick around.

They don’t. That’s a thing in movies. When things go wrong it’s usually caused by damage and/or pilot error.

Pilot here- it’s 99% theatrics to make it more dramatic in TV and movies.

The 1% of the time when it’s real would occur in only a couple situations.

In a fly-by-wire aircraft, the pilot’s inputs are fed into a computer that in turn actuates the control surfaces. A malfunction in the computer that causes a sudden, extreme control input, such as what happened in [Flight 302](https://en.m.wikipedia.org/wiki/Ethiopian_Airlines_Flight_302) would be a situation likely to have the pilots fighting the controls to override the input (though there are established procedures that go beyond just fighting the control input)

In a manual flight control aircraft, where movements of the flight controls move pulleys and wires attached to the control surfaces, a failure such as a jammed pulley or sudden disconnection could leave a control surface-and the plane- in a dangerous configuration in which the pilots might be attempting extreme control inputs to stabilize the aircraft.

But overall, dramatically fighting the controls as in movies is a mostly futile endeavor. There are procedures and redundancies in place in most aircraft that make it unnecessary.

They don’t, that’s just in the movies. In fact fighting the controls can make things worse. A perfect example is [American Airlines Flight 587](https://en.wikipedia.org/wiki/American_Airlines_Flight_587), the aircraft flew into the turbulence behind another aircraft, and the First Officer, who was the pilot flying, panicked and fought the rudder so hard that he ripped the tail off causing the aircraft to crash killing everyone.

As others have said, that’s largely theatrics in movies and TV.

There are essentially three systems in use:

* Fly-by-wire is what you will predominantly see in modern airliners and military aircraft. Here, your stick isn’t actually physically linked to any control surface – instead, your inputs send signals to a computer which then positions flight control surfaces to do what you are asking the computer to do. The computers are, in relaxed stability aircraft (like fighter jets), actually continuously sending signals to the flight controls to keep the jet flying stable. In some aircraft, if you turn off the flight control computers entirely, your jet is no longer able to maintain controlled flight.

In this case, the fighting control stick does absolutely nothing. In fact, you won’t even feel the actual feedback from flight control surfaces on aircraft because the stick isn’t directly linked to them.

* Hydromechanical. This is used in older fighter jets and in airliners/aircraft with big control surfaces. Basically, when flying at faster speeds (which creates larger pressure/air loads on control surfaces), human power isn’t enough so the control stick is *mechanically* linked to hydraulic systems that move the control surfaces for you. These hydraulic circuits operate in the thousands of psi. For instance, if you pull the stick back, you are mechanically telling the servos and actuators to move the stabilator (or elevators) to pitch the aircraft up.

In this case, if you did have something go wrong, fighting the stick doesn’t do much either. Most likely, if something went wrong, it’s because your hydraulic line or mechanical linkage broke, or you lost a control surface. In which case, fighting the controls won’t do you anything.

* Direct linkage. This is what you commonly see in older aircraft/lighter aircraft/general aviation like in your Cessna. Here your control surfaces are directly linked to your control stick/rudder via wires and pulleys. You will directly feel the loads on the control surfaces.

Here is where you could, like in the movies, perhaps try to fight for control via physically fighting the stick more. A jammed linkage or connection might require more force to fight through. But even then, you risk breaking something even worse (sudden snapping of control surfaces can overwhelm mechanical limits) OR getting into a PIO (pilot induced oscillation).

MORE likely to happen is if you have a failure in a control surface (e.g. an aileron fails), you have to put in some input like rudder or opposite aileron to keep the plane flying straight and level. In that case, you are “fighting the controls” by keeping some force on the stick to maintain the flight attitude you want. But you aren’t “fighting the stick” like in the movies – instead, you’re precisely and finely putting your control inputs in (or trimming the aircraft) to offset what was lost.

One thing I haven’t seen directly mentioned is World War II era fighters/bombers were all cables and pulley rigging for the control surfaces. If those planes dive at the ground during dogfights or attack runs and get going really fast, the forces to move the controls becomes extreme. Thus, you could get into a dive you couldn’t physically pull out of.

So, this can be quite realistic for some movies but for modern aircraft the biggest issue where a pilot is straining against the controls is something like runaway trim/autopilot. For most everything else you’re not fighting with the controls.

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There is one plane crash (can’t remember which one ) where the two pilote were inputting opposite order on the stick, basically fighting each other
Edit: it’s [AirAsia Flight 8501](https://en.wikipedia.org/wiki/Indonesia_AirAsia_Flight_8501)

Don’t know if the two sticks are linked

Helicopter pilot, answer is you don’t unless the hydraulic system has failed. This is less likely the larger the helicopter as they have multiple independent hydraulic systems so one failing has no effect at all. Smaller helicopters like Jetrangers or Astars are harder to control with a hydraulic failure but not even that bad, we train to land with the hydraulics off by flying real aircraft with the hydraulics turned off, it isn’t considered dangerous to do so. For a large helicopter if you somehow had all hydraulics fail at the same time depending on the type it is a major emergency and possibly unrecoverable.

It depends on the failure, if you lose an engine in a twin then you have to step on the running engine with the rudder otherwise the plane will yaw in the direction of the failed engine due to the power imbalance – and you have to do it very quickly. Novice pilots will instinctively push the throttle forward on the still running engine (which you need to do to maintain power) but will forget to step on the rudder. Twin engine-out training is one of the most challenging and dangerous parts of flight training. It accounts for a large share of deaths in general aviation and a good chunk of them are during training.

The other factor is that often the autopilot will shut off during a catastrophic failure and you need to make up for whatever the autopilot was doing for you. It isn’t normally very dramatic, though, either in engine out or auto-pilot disconnect situations. The pilot will grab the controls and make fluid and firm inputs to the controls to keep the aircraft in balanced flight.

Do they? Or is that just what you’ve seen in movies?

Another pilot here. All the controls in my plane are directly connected to the yoke and pedals (manual). When airflow is low, especially during slow flight such as during landings, controls require exaggerated expression. They don’t have much lift being generated to cause a change.
Alternatively, very strong winds in lighter aircraft can definitely cause you to fight. They can quickly push you and change your pitch, yaw, and roll (these are the axis of motion). In this case you have to counter the effects of the wind.

Most of this is experienced extensively by all pilots in training. But it can take real physical effort (without much return from the controls). Usually however, you fly with “two fingers”. A light touch will do it 9 times out of 10 if you’re trimmed in (tuned controls to stable). Remember, flight is across long distances and you generally navigate on 10° increments (eg 010° – 360°) or smaller so planes must fly on small movements and corrections not grant turns like you see on movies.

The only times I’ve ever done movement like that when not training and with passengers was during some landings where the wind goes dead on me or once with an engine out on takeoff with about 400 feet below me to return to runway.

Probably the same reason in NASCAR movies the cars have 73 gears and that final majestic last gear that only the hero uses to win the race when all the other drivers were afraid to do so.

In other words: pure bullshit purely for the sake of cinamatics.

Helicopter pilot here. Our controls are “boosted” meaning that our physical inputs get amplified by hydroelectric motors. If we lose boost, then it’s just our physical inputs controlling the aircraft which sometimes is insanely difficult and strenuous. Some helicopters like the MH-53 are impossible to control without hydraulic boost.

we don’t. you’ve been watching too many movies.

most of the time the pressure from your pinky is enough to make all flight adjustments.

if there’s moderate to heavy turbulence, I’ll hold on with my hand

If it’s heavy or more, I’ll stay home.

Answer: Former helicopter mechanic and crew chief here. Helicopters have a mechanical linkage from pilot input to control output. These linkages are hydraulic assisted. In emergency situations, you may lose or have to disable the hydraulic servos. As you can imagine, the feedback from the rotor blades can make it quite difficult to smoothly operate.

As an example, when you drive your car, stick your hand out the window and feel the air flowing. Your muscles are the servos controlling your hand. Now imagine you didn’t have control of your finger but still control hand overall. It’s a rough, but you can still keep your hand more or less in place, even if the finer details aren’t the same.

Plenty of great answers already so I’ll just add there’s a very interesting podcast that answers questions like these and talks incidents called Black Box Down!