  Fission-related phenomena of heavy $\Lambda$ hypernuclei are discussed with
the constraint Skyrme-Hartree-Fock+BCS (SHF+BCS) method, in which a similar
Skyrme-type interaction is employed also for the interaction between a
$\Lambda$ particle and a nucleon. Assuming that the $\Lambda$ particle
adiabatically follows the fission motion, we discuss the fission barrier height
of $^{239}_{\Lambda}$U. We find that the fission barrier height increases
slightly when the $\Lambda$ particle occupies the lowest level. In this case,
the $\Lambda$ particle is always attached to the heavier fission fragment. This
indicates that one may produce heavy neutron-rich $\Lambda$ hypernuclei through
fission, whose weak decay is helpful for the nuclear transmutation of
long-lived fission products. We also discuss cases where the $\Lambda$ particle
occupies a higher single-particle level.
