According to Newton 3rd law, every action has reaction force in the opposite direction. That's how spaceship can move in space. That's why helicopter needs a second propeller in the back to prevent it from spinning in the opposite direction of the main propeller. But why single propeller planes do not rotate around its horizontal axis opposing the rotation of its propeller ?

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    $\begingroup$ Actually, they do. Understanding Propeller Torque and P-Factor and Propeller Torque Effect $\endgroup$ – Greg Hewgill Jul 23 '19 at 3:25
  • $\begingroup$ They do. That's why you apply opposite rudder to counteract the torque when starting the takeoff run. $\endgroup$ – Therac Jul 23 '19 at 3:47
  • $\begingroup$ I like how the dupe target is itself a dupe. :) $\endgroup$ – FreeMan Jul 23 '19 at 16:36
  • $\begingroup$ I remember seeing a doco about a Spitfire being restored. The last step for a conditional airworthiness certificate involved the inspector, upon returning from a short flight where roll trim was a problem (due to torque reaction) & the lack of cockpit aileron trim adjustment, taking two blocks of wood (while assuring that this was standard WW2 practice) & very carefully bashed a small part of the trailing edge of the aileron, slightly bending it a fraction of an inch over a few inches in length, so it would impart a force on the aileron at cruising speed to counter the roll tendency. It worked $\endgroup$ – Mackk Jul 24 '19 at 5:32