Very little – 10% or less of the total weight on a commercial aircraft. The main gear is designed to carry all the load and is set just aft of the Center of Gravity.
The main gear takes all the impact of the landing and the nose only touches down when the spoilers deploy. There are no brakes on the front gear, so they don’t have to deal with those forces.
The fact that the main gear is so close to the CG can cause problems when the plane is not loaded carefully.
DC-10/MD-11’s were infamous for their small CG envelope. But it also happens to other planes. Jacks under the tail are often used to prevent this problem.
This is also why they don’t load passengers from the back to front
Author – Glenn Tomchik
