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So if the rudder fails or gets stuck in the “left” position a pilot could open the right door and it would essentially counter the effect?

George Clooney In a Mooney
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    A little, yes, but it's extremely ineffective because it's so far forward. Most small aircraft will fly fine with an inop rudder as long as the rudder isn't stuck in some extreme position. – Ron Beyer Jan 06 '20 at 23:45
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    How would you open a door and hold it open against a 120 mph wind? – Carey Gregory Jan 06 '20 at 23:49
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    @CareyGregory If your rudder fails (cables snap or gets stuck) in flight, you'd want to get about as slow as you are comfortable going. The rudder is a lot less effective as speeds slow down, so the slower you go, the easier it is to control by other means. But yes, even at 65 knots, the door is very hard to open (and close), I have quite a bit of personal experience with that unfortunately. – Ron Beyer Jan 06 '20 at 23:53
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    @CareyGregory kind of. But more so how would it react to counter the rudder stuck in a certain position – George Clooney In a Mooney Jan 07 '20 at 00:46
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    "How would you open a door and hold it open against a 120 mph wind? " -- if it's hard to hold open, that's a good thing. Indicates lots of sideforce is being generated. Not unrelated to yaw torque. – quiet flyer Jan 07 '20 at 01:49
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    If you happen to be flying say a Piper Cherokee, you don't have the option of opening the left door, 'cause there isn't one? But it's also hard to imagine a situation (other than perhaps a crosswind landing) where you'd ever have more than a few degrees of rudder, or where a rudder failure would do anything but leaving it free in the airstream. – jamesqf Jan 07 '20 at 05:26
  • @RonBeyer please re open the question as it has not been asked before. – George Clooney In a Mooney Jan 07 '20 at 08:32
  • I'm only one of 5 votes to close. If you want it reopened, please edit to explain the difference between this and the linked question. – Ron Beyer Jan 07 '20 at 12:48
  • @RonBeyer Re flying at low speed when the rudder fails, my understanding was that you want to fly faster than the crossover airspeed if there's a rudder hardover. Above the crossover airspeed, the ailerons can overpower the rudder; below the crossover airspeed, the opposite happens. – Tanner Swett Jan 07 '20 at 21:50
  • @Firefighter1 Have you read the answers to the linked question ("How does turning a small plane by opening the doors work")? If so, can you explain what else you'd like to know that isn't answered by the answers over there? – Tanner Swett Jan 07 '20 at 21:51
  • @TerranSwett This may be true for commercial aircraft, but how many GA aircraft do you know with a published crossover airspeed, if they even have one? I know that my ailerons in my 177 have a lot more authority than the rudder does, even at slow speeds (given I can side-slip to a landing and still maintain directional control). – Ron Beyer Jan 07 '20 at 23:32

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In reality, in a strongly- deflected stuck-rudder situation, the pilot would be best advised to forget about the doors and just land the plane, selecting a runway with a strong crosswind component if at all possible. After all, when landing with a strong crosswind, it's not that uncommon to hold the rudder at close to full deflection in the "downwind" direction. If no crosswind runway is available, the pilot will just have to land the plane going a bit sideways-- no problem if the aircraft happens to have tricycle gear, like most do these days.

Obviously, in a stuck-rudder situation, steering corrections must be accomplished entirely via bank angle changes via the ailerons. Keeping the rate of change of aileron deflection (and bank angle) low will help smooth things out.

quiet flyer
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