Loading with an AFT CG - Flight Training Video

[@shanek4824]

Thank you for your video. It's been a while since Ground School, good review.#TFP

[@nicscov]

I've always read and heard that the C.G. is the point at which the airplane would theoretically be balanced on. A, "Fulcrum" if you will. So whenever I hear someone say "aft CG" I imagine the fulcrum moving aft and thus you have a heavier nose. I've drawn a crude representation, but to me that looks like the tail (the left) would be pitching down; because, see-saws. My question is, WHY this is not the case? Or is this just bad lingo in aviation? -----------^---

[@TheWindigomonster]

As far as I can understand, I think your confusion is arising from the connection you're making to see-saws. All the center of gravity is representing is the point where the weight is being concentrated. The only reason a see-saw is balancing from a point in the middle is because its CG happens to be in the dead center. If you were to put a bunch of weight on one side, its CG would shift and you would have to move the pillar that's anchoring it to the ground in order for it to be balanced again.

[@whiskeytuesday]

So the thing about this is that the centre of gravity is not the fulcrum, it's the point where the fulcrum would have to be in order to not require force input to be balanced. The centre of pressure, sometimes called centre of lift, is the longitudinal fulcrum of the plane (when in motion that is, if the plane were hanging from a crane or something the fulcrum would be wherever you happened to attach the cable). If the centre of gravity were (by careful loading or something) located exactly on top of the centre of pressure (fulcrum) you would be able to fly straight and level without elevators. You wouldn't be able to get to altitude of course, and the CoP moves as speed changes, and CoG changes as fuel burns, and, like, if you move anything at all... so you probably want to keep the plane as it is all things considered.

[@Poop-nu1so]

@@whiskeytuesday i know your comment is a year old, but if you see this thanks. This is how i envisioned it but wanted to be sure

[@whiskeytuesday]

@@Poop-nu1so I'm glad it helped, this stuff can be hard to picture sometimes. Also, I don't remember writing this comment at all, strangely.

[@bestdeal3808]

Example: 2200 rpm with fwd cg vs 2200 rpm with aft cg. = 5 kias, 10 kias, 20 kias? We know a aft cg has a higher cruise speed, but how much higher?

[@TheFinerPoints]

In an airplane this size it's 5 or less, but you burn less fuel too. I can say that from experience not from any equation I just rant