  Motivated by experimental indications of a significant presence of heavy
nuclei in the cosmic ray flux at ultra high energies ($\gtrsim 10^{19} \eV$),
we consider the effects of Planck scale suppressed Lorentz Invariance Violation
(LIV) on the propagation of cosmic ray nuclei. In particular we focus on LIV
effects on the photodisintegration of nuclei onto the background radiation
fields. After a general discussion of the behavior of the relevant quantities,
we apply our formalism to a simplified model where the LIV parameters of the
various nuclei are assumed to kinematically result from a single LIV parameter
for the constituent nucleons, $\eta$, and we derive constraints on $\eta$.
Assuming a nucleus of a particular species to be actually present at $10^{20}$
eV the following constraints can be placed: $-3\times10^{-2} \lesssim \eta
\lesssim 4$ for $^{56}$Fe, $-2\times10^{-3} \lesssim \eta \lesssim
3\times10^{-2}$ for $^{16}$O and $-7\times10^{-5} \lesssim \eta \lesssim
1\times10^{-4}$ for $^{4}$He, respectively.
