This is the part of your vehicle that holds the vehicle together. For most vehicles, this is an external skeleton, wrapped with enough material to hold it all together.

Decide how much Structural Strength you want. A higher Structural Strength will result in the vehicle being able to absorb more damage, and resist stresses due to high-speed turns or deep diving, but will eat into your available mass rather quickly. A value of 2 is good for most civilian applications; most military applications will want 4 or more. A value of 15 is the practical limit.

If your vehicle is a spacecraft or submarine, consider its Structural Strength to be four points higher. This is to account for the mass of environmental sealing. If it is a surface ship, consider its Structural Strength to be one point higher, for purposes of floatation and water sealing. This increase in Structural Strength applies only for purposes of calculating Mass and Cost, and does not count towards the vehicle's hull points.

To determine the quality of your endostructure, consult the table below.

Multiply your Area by the Mass value for your structure, and then by your Structural Strength value. This gives the mass of your endostructure. To find the cost, multiply your Area by the Structural Strength value, and then by ₠25.

You can install a lower-quality structure to keep the price down. Increase the final mass of your endostructure by 50%, but cut the cost in half.

You can also install a higher-quality structure to reduce the mass. Halve the final mass of your endostructure, but multiply its cost by five.

If your vehicle has wings, multiply the cost of the endostructure by ten.

If your vehicle is a submarine, double both the mass of the endostructure and its cost.

If your vehicle has streamining better than Mild, find the cost multiplier on the Streamlining table.

Hull Points are a measure of the damage that the vehicle can absorb and still be able to function. If a vehicle's hull points are depleted, the vehicle will be destroyed.

To find the vehicle's hull points, multiply its Area value by its chosen Structural Strength, and then multiply by 4. Drop fractions.

If your vehicle is a walker, use it's hull-only Area modifier to calculate its body hull points. Then do the same for its legs, using the individual Area value worked out when you selected the leg. If a leg loses all of its hull points, it is blown off, and the vehicle will be slowed or immobilized.

If you want to know the hull points of your wings, find the amount of Area you added specifically for wings. Work out the wing's hull points based on that area, then divide by your total number of wings before dropping fractions. Remember to subtract the hull points for the wings from your total hull points. If a wing loses all of its hull points, it will be blown off, and the vehicle will likely no longer be able to fly.