index plane

index plane

[′in‚deks ‚plān]
(geology)
A surface used as a reference point in determining geological structure.
References in periodicals archive ?
> [DELTA]TX = 1069 N force applied to index plane of fuselage near wall No.
> [DELTA]TZ = -4250 N force applied to index plane of fuselage near wall No.
> -4070 N force TX applied to the index plane of the fuselage near wall no.