L-1011 Weight and Balance: Overview

Over the next few blog posts we will take a look at the weight and balance limitations of the L-1011 and how to compute them. This is actually quite an interesting exercise in flight simulation since it also validates the physics model of the flight simulator. Load and Balance data is importation so that the flight crew and other personnel operate the aircraft within its operation envelope.

There are a few basic concepts that are used when calculating weight and balance of the Lockheed L-1011. To start with we will have a look at the profile of the aircraft (see above). Everyone is familiar with the basic size of the L-1011, but perhaps not how that can relate to weight and balance.

You might note form the diagram above that Station 0 is some 183 inches forward of the nose of the aircraft. This is designed that way so that if additional structure is added to the nose, the radome is changed or other things we will not end up with a negative number.

Additionally, you'll notice that the main floorboard of the aircraft is water line 200. The pavement on with the aircraft sits is water line 19. That means that water line 0 is some 19 inches below the surface of the earth! :) Again, this is done to avoid negative numbers. Working form forward to aft you might note that the landing gear is sitting at Station 540 when extended, and will retract to about Station 440 ... some 100 inches! This will have to be accounted for in the operational loading limits.

You might also note the relative position of the cargo compartments to the landing gear and wing arrangement.  In terms of weight and balance we can see how easy it is to have rather large moment changes on the L-1011. The overall length of the aircraft is some 164 feet, 2 inches which amount to 1970 inches !