  We consider the dimensional reduction of eleven dimensional supergravity to
type IIA in ten dimensions, and study the conditions for supersymmetry in terms
of p-form spinor bi-linears of the supersymmetry parameter. For a bosonic
solution to be supersymmetric these p-forms must satisfy a set of differential
relations, which we derive in full; the supersymmetry variations of the
dilatino give a set of algebraic relations which are also derived. These
results are then used to provide the generalized calibration conditions for
some of the basic brane solutions, we also follow up a suggestion of
Hackett-Jones and Smith and present a calibration condition for IIA supertubes.
We find that a probe supertube satisfies this bound but does not saturate it,
with the bound successfully accounting for the D0 charge of the supertube but
not the string charge; we speculate that there should be a stronger calibration
inequality than the one given.
