I second stopping the repitition of the same dam information.

and I stop the repetition of the same damn information.

correct, WD does stand for water displacement, and the 40 is the 40th formula. also it was invented by howard hues, for use on the spruce goose.

And the 40 stands for the 40th time making the formula

And the 40 stands for Formula number 40 for the 40th try