Hey guys, Jacob here. Welcome back to Helicopter Lessons in 10 minutes or less. This is episode 2. Today I'll be covering gyroscopic precession.
This is important to us, especially helicopter pilots, because it applies to all rotating bodies. specifically our rotor blades. Now some videos explain this concept using a bicycle wheel on a string to show the concept as it applies to general physics, but my goal here is to explain it specifically as it applies to a rotor system.
But that said, what exactly is gyroscopic? procession. It's the phenomenon of procession occurring in rotating bodies that manifests as an applied force occurring 90 degrees after application in the direction of rotating. So what does that mean?
Let's say we have an object that is rotating. In this case we'll do counterclockwise. This means that if I have any kind of action, do any kind of input at this point in the disc or in this point of the rotating body, it will actually occur 90 degrees later.
So if anybody's ever done any buffing with an electric buffer, you'll notice that you can't turn the thing simply by doing left and right. You actually have to do up and down to turn it left and right. So how does this apply to a helicopter? Well here's our fuselage and our rotor disc. What this means is that if we have any kind of application, say at the nose of the aircraft, after this, we'll say an increase in pitch on the nose of the aircraft, it's actually are going to manifest 90 degrees later as an increase in pitch on the left side, and that would be inducing a right roll.
Same thing holds true if we were to do something on the aft portion of the rotor, it would manifest 90 degrees later as an increase in pitch on the right side of the rotor, inducing a left turn. Now same thing applies to forward and aft deceleration, an increase on the right side would manifest as an increase in pitch on the forward side of the disc, causing the pitching up of it. and resulting in a deceleration and vice versa for the aft causing a acceleration.
Now luckily when you fly you don't have to think about compensating for a 90 degree difference. This has already been done for you with the flight control rigging. As a pilot when you want to do a left turn in flight you move the controls to the left the swash plate increases the pitch at the rear of the rotor disc this action manifests 90 degrees later as they roll to the left. So it's a pretty basic concept gyroscopic precession that that wraps it up. up but it's important to understand because it applies to many other concepts that we'll go over later so that being said thanks for watching stay tuned for more episodes if you like the video let me know give me a thumbs up or comment in the comment section below thank you guys