Why in helicopter autorotation phase the opposing torque is eliminated? Unicorn Meta Zoo #1: Why another podcast? Announcing the arrival of Valued Associate #679: Cesar ManaraPrinciple of aerodynamic lift: are misconceptions also taught in flight schools?In helicopters, why not have electric motors controlling blade pitch?What is the relationship between the UH60 Blackhawk stabilator function lateral sideslip and pitch coupling?Why doesn't a single engine airplane rotate along the longitudinal axis?Does lift equal weight in a climb?Why the need to use right rudder during stall recovery?Why is *vertical* autorotation in a helicopter not recommended?Is lift created by air downwash?Which are some planes shaped like an inverted wing?Is autorotation possible in a tandem rotored helicopter?

Retract an already submitted recommendation letter (written for an undergrad student)

How long after the last departure shall the airport stay open for an emergency return?

Does Feeblemind produce an ongoing magical effect that can be dispelled?

Split coins into combinations of different denominations

A strange hotel

What ability score does a Hexblade's Pact Weapon use for attack and damage when wielded by another character?

Implementing 3DES algorithm in Java: is my code secure?

Justification for leaving new position after a short time

"Rubric" as meaning "signature" or "personal mark" -- is this accepted usage?

Seek and ye shall find

What's parked in Mil Moscow helicopter plant?

Are these square matrices always diagonalisable?

What is the ongoing value of the Kanban board to the developers as opposed to management

What is the term for a person whose job is to place products on shelves in stores?

Will I lose my paid in full property

What do you call the part of a novel that is not dialog?

How to keep bees out of canned beverages?

My admission is revoked after accepting the admission offer

What was Apollo 13's "Little Jolt" after MECO?

Trumpet valves, lengths, and pitch

Book with legacy programming code on a space ship that the main character hacks to escape

With indentation set to `0em`, when using a line break, there is still an indentation of a size of a space

Check if a string is entirely made of the same substring

I preordered a game on my Xbox while on the home screen of my friend's account. Which of us owns the game?



Why in helicopter autorotation phase the opposing torque is eliminated?



Unicorn Meta Zoo #1: Why another podcast?
Announcing the arrival of Valued Associate #679: Cesar ManaraPrinciple of aerodynamic lift: are misconceptions also taught in flight schools?In helicopters, why not have electric motors controlling blade pitch?What is the relationship between the UH60 Blackhawk stabilator function lateral sideslip and pitch coupling?Why doesn't a single engine airplane rotate along the longitudinal axis?Does lift equal weight in a climb?Why the need to use right rudder during stall recovery?Why is *vertical* autorotation in a helicopter not recommended?Is lift created by air downwash?Which are some planes shaped like an inverted wing?Is autorotation possible in a tandem rotored helicopter?










1












$begingroup$


As you many know, according to Newton's 3rd law for every action there is an equal and opposite reaction, as the main rotor of a helicopter turns in one direction, the fuselage tends to rotate in opposite direction but when there is no engine power during autorotation, there is no torque reaction, why???










share|improve this question









$endgroup$







  • 1




    $begingroup$
    "according to Newton's 3rd law for every action there is an equal and opposite reaction" - Newton's third law doesn't say that. Newton's third law says that if one object exerts a force on a second object, then the second object also exerts a force on the first object, equal in magnitude but opposite in direction.
    $endgroup$
    – Tanner Swett
    Apr 20 at 17:40















1












$begingroup$


As you many know, according to Newton's 3rd law for every action there is an equal and opposite reaction, as the main rotor of a helicopter turns in one direction, the fuselage tends to rotate in opposite direction but when there is no engine power during autorotation, there is no torque reaction, why???










share|improve this question









$endgroup$







  • 1




    $begingroup$
    "according to Newton's 3rd law for every action there is an equal and opposite reaction" - Newton's third law doesn't say that. Newton's third law says that if one object exerts a force on a second object, then the second object also exerts a force on the first object, equal in magnitude but opposite in direction.
    $endgroup$
    – Tanner Swett
    Apr 20 at 17:40













1












1








1





$begingroup$


As you many know, according to Newton's 3rd law for every action there is an equal and opposite reaction, as the main rotor of a helicopter turns in one direction, the fuselage tends to rotate in opposite direction but when there is no engine power during autorotation, there is no torque reaction, why???










share|improve this question









$endgroup$




As you many know, according to Newton's 3rd law for every action there is an equal and opposite reaction, as the main rotor of a helicopter turns in one direction, the fuselage tends to rotate in opposite direction but when there is no engine power during autorotation, there is no torque reaction, why???







aerodynamics helicopter






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Apr 20 at 5:28









Mehdi shelbyMehdi shelby

9816




9816







  • 1




    $begingroup$
    "according to Newton's 3rd law for every action there is an equal and opposite reaction" - Newton's third law doesn't say that. Newton's third law says that if one object exerts a force on a second object, then the second object also exerts a force on the first object, equal in magnitude but opposite in direction.
    $endgroup$
    – Tanner Swett
    Apr 20 at 17:40












  • 1




    $begingroup$
    "according to Newton's 3rd law for every action there is an equal and opposite reaction" - Newton's third law doesn't say that. Newton's third law says that if one object exerts a force on a second object, then the second object also exerts a force on the first object, equal in magnitude but opposite in direction.
    $endgroup$
    – Tanner Swett
    Apr 20 at 17:40







1




1




$begingroup$
"according to Newton's 3rd law for every action there is an equal and opposite reaction" - Newton's third law doesn't say that. Newton's third law says that if one object exerts a force on a second object, then the second object also exerts a force on the first object, equal in magnitude but opposite in direction.
$endgroup$
– Tanner Swett
Apr 20 at 17:40




$begingroup$
"according to Newton's 3rd law for every action there is an equal and opposite reaction" - Newton's third law doesn't say that. Newton's third law says that if one object exerts a force on a second object, then the second object also exerts a force on the first object, equal in magnitude but opposite in direction.
$endgroup$
– Tanner Swett
Apr 20 at 17:40










3 Answers
3






active

oldest

votes


















5












$begingroup$

Because the engine is not applying power to the rotors. No engine power means there will be no torque pushing the airframe in the opposite direction.



In auto, the main rotor essentially becomes a pinwheel, kept moving by the air rushing past it...



Auto doesn't really power the rotors, it keeps them moving so that the spinning rotor creates air resistance and slows the descent of the helicopter, and maintains enough inertia in the blades to flare and stop the descent.



Of course, that inertia is only sufficient for one attempt at flaring and stopping descent.






share|improve this answer









$endgroup$




















    4












    $begingroup$

    Because the torque to spin it is being generated within the rotor itself, being a forward thrust component of the lift being generated by the spinning blades, like any gliding aircraft. An autorotating rotor is like two gliders with velcro wingtips going toward each other in opposite directions, who when they pass each other hook wingtips and start to spin around each other, still gliding and moving forward, but forced into a circle who's axis is their inboard wing tips.



    What ever rotational force is transmitted to the airframe (a tiny amount) is actually in the same direction as the rotor's rotation; not a torque reaction, just friction drag from the main shaft bearings and sprag clutch.






    share|improve this answer









    $endgroup$




















      1












      $begingroup$

      In autorotation, the engine and gearbox are not applying any turning force, or torque to the rotor system, so therefore there is no torque reaction in the opposite direction.






      share|improve this answer









      $endgroup$













        Your Answer








        StackExchange.ready(function()
        var channelOptions =
        tags: "".split(" "),
        id: "528"
        ;
        initTagRenderer("".split(" "), "".split(" "), channelOptions);

        StackExchange.using("externalEditor", function()
        // Have to fire editor after snippets, if snippets enabled
        if (StackExchange.settings.snippets.snippetsEnabled)
        StackExchange.using("snippets", function()
        createEditor();
        );

        else
        createEditor();

        );

        function createEditor()
        StackExchange.prepareEditor(
        heartbeatType: 'answer',
        autoActivateHeartbeat: false,
        convertImagesToLinks: false,
        noModals: true,
        showLowRepImageUploadWarning: true,
        reputationToPostImages: null,
        bindNavPrevention: true,
        postfix: "",
        imageUploader:
        brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
        contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
        allowUrls: true
        ,
        noCode: true, onDemand: true,
        discardSelector: ".discard-answer"
        ,immediatelyShowMarkdownHelp:true
        );



        );













        draft saved

        draft discarded


















        StackExchange.ready(
        function ()
        StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faviation.stackexchange.com%2fquestions%2f62517%2fwhy-in-helicopter-autorotation-phase-the-opposing-torque-is-eliminated%23new-answer', 'question_page');

        );

        Post as a guest















        Required, but never shown

























        3 Answers
        3






        active

        oldest

        votes








        3 Answers
        3






        active

        oldest

        votes









        active

        oldest

        votes






        active

        oldest

        votes









        5












        $begingroup$

        Because the engine is not applying power to the rotors. No engine power means there will be no torque pushing the airframe in the opposite direction.



        In auto, the main rotor essentially becomes a pinwheel, kept moving by the air rushing past it...



        Auto doesn't really power the rotors, it keeps them moving so that the spinning rotor creates air resistance and slows the descent of the helicopter, and maintains enough inertia in the blades to flare and stop the descent.



        Of course, that inertia is only sufficient for one attempt at flaring and stopping descent.






        share|improve this answer









        $endgroup$

















          5












          $begingroup$

          Because the engine is not applying power to the rotors. No engine power means there will be no torque pushing the airframe in the opposite direction.



          In auto, the main rotor essentially becomes a pinwheel, kept moving by the air rushing past it...



          Auto doesn't really power the rotors, it keeps them moving so that the spinning rotor creates air resistance and slows the descent of the helicopter, and maintains enough inertia in the blades to flare and stop the descent.



          Of course, that inertia is only sufficient for one attempt at flaring and stopping descent.






          share|improve this answer









          $endgroup$















            5












            5








            5





            $begingroup$

            Because the engine is not applying power to the rotors. No engine power means there will be no torque pushing the airframe in the opposite direction.



            In auto, the main rotor essentially becomes a pinwheel, kept moving by the air rushing past it...



            Auto doesn't really power the rotors, it keeps them moving so that the spinning rotor creates air resistance and slows the descent of the helicopter, and maintains enough inertia in the blades to flare and stop the descent.



            Of course, that inertia is only sufficient for one attempt at flaring and stopping descent.






            share|improve this answer









            $endgroup$



            Because the engine is not applying power to the rotors. No engine power means there will be no torque pushing the airframe in the opposite direction.



            In auto, the main rotor essentially becomes a pinwheel, kept moving by the air rushing past it...



            Auto doesn't really power the rotors, it keeps them moving so that the spinning rotor creates air resistance and slows the descent of the helicopter, and maintains enough inertia in the blades to flare and stop the descent.



            Of course, that inertia is only sufficient for one attempt at flaring and stopping descent.







            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered Apr 20 at 7:31









            tj1000tj1000

            6,8701033




            6,8701033





















                4












                $begingroup$

                Because the torque to spin it is being generated within the rotor itself, being a forward thrust component of the lift being generated by the spinning blades, like any gliding aircraft. An autorotating rotor is like two gliders with velcro wingtips going toward each other in opposite directions, who when they pass each other hook wingtips and start to spin around each other, still gliding and moving forward, but forced into a circle who's axis is their inboard wing tips.



                What ever rotational force is transmitted to the airframe (a tiny amount) is actually in the same direction as the rotor's rotation; not a torque reaction, just friction drag from the main shaft bearings and sprag clutch.






                share|improve this answer









                $endgroup$

















                  4












                  $begingroup$

                  Because the torque to spin it is being generated within the rotor itself, being a forward thrust component of the lift being generated by the spinning blades, like any gliding aircraft. An autorotating rotor is like two gliders with velcro wingtips going toward each other in opposite directions, who when they pass each other hook wingtips and start to spin around each other, still gliding and moving forward, but forced into a circle who's axis is their inboard wing tips.



                  What ever rotational force is transmitted to the airframe (a tiny amount) is actually in the same direction as the rotor's rotation; not a torque reaction, just friction drag from the main shaft bearings and sprag clutch.






                  share|improve this answer









                  $endgroup$















                    4












                    4








                    4





                    $begingroup$

                    Because the torque to spin it is being generated within the rotor itself, being a forward thrust component of the lift being generated by the spinning blades, like any gliding aircraft. An autorotating rotor is like two gliders with velcro wingtips going toward each other in opposite directions, who when they pass each other hook wingtips and start to spin around each other, still gliding and moving forward, but forced into a circle who's axis is their inboard wing tips.



                    What ever rotational force is transmitted to the airframe (a tiny amount) is actually in the same direction as the rotor's rotation; not a torque reaction, just friction drag from the main shaft bearings and sprag clutch.






                    share|improve this answer









                    $endgroup$



                    Because the torque to spin it is being generated within the rotor itself, being a forward thrust component of the lift being generated by the spinning blades, like any gliding aircraft. An autorotating rotor is like two gliders with velcro wingtips going toward each other in opposite directions, who when they pass each other hook wingtips and start to spin around each other, still gliding and moving forward, but forced into a circle who's axis is their inboard wing tips.



                    What ever rotational force is transmitted to the airframe (a tiny amount) is actually in the same direction as the rotor's rotation; not a torque reaction, just friction drag from the main shaft bearings and sprag clutch.







                    share|improve this answer












                    share|improve this answer



                    share|improve this answer










                    answered Apr 20 at 13:45









                    John KJohn K

                    26.6k14182




                    26.6k14182





















                        1












                        $begingroup$

                        In autorotation, the engine and gearbox are not applying any turning force, or torque to the rotor system, so therefore there is no torque reaction in the opposite direction.






                        share|improve this answer









                        $endgroup$

















                          1












                          $begingroup$

                          In autorotation, the engine and gearbox are not applying any turning force, or torque to the rotor system, so therefore there is no torque reaction in the opposite direction.






                          share|improve this answer









                          $endgroup$















                            1












                            1








                            1





                            $begingroup$

                            In autorotation, the engine and gearbox are not applying any turning force, or torque to the rotor system, so therefore there is no torque reaction in the opposite direction.






                            share|improve this answer









                            $endgroup$



                            In autorotation, the engine and gearbox are not applying any turning force, or torque to the rotor system, so therefore there is no torque reaction in the opposite direction.







                            share|improve this answer












                            share|improve this answer



                            share|improve this answer










                            answered Apr 20 at 14:43









                            J. SouthworthJ. Southworth

                            89026




                            89026



























                                draft saved

                                draft discarded
















































                                Thanks for contributing an answer to Aviation Stack Exchange!


                                • Please be sure to answer the question. Provide details and share your research!

                                But avoid


                                • Asking for help, clarification, or responding to other answers.

                                • Making statements based on opinion; back them up with references or personal experience.

                                Use MathJax to format equations. MathJax reference.


                                To learn more, see our tips on writing great answers.




                                draft saved


                                draft discarded














                                StackExchange.ready(
                                function ()
                                StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faviation.stackexchange.com%2fquestions%2f62517%2fwhy-in-helicopter-autorotation-phase-the-opposing-torque-is-eliminated%23new-answer', 'question_page');

                                );

                                Post as a guest















                                Required, but never shown





















































                                Required, but never shown














                                Required, but never shown












                                Required, but never shown







                                Required, but never shown

































                                Required, but never shown














                                Required, but never shown












                                Required, but never shown







                                Required, but never shown







                                Popular posts from this blog

                                Sum ergo cogito? 1 nng

                                419 nièngy_Soadمي 19bal1.5o_g

                                Queiggey Chernihivv 9NnOo i Zw X QqKk LpB