  We present exact tree level cross sections for the single top production
process $e^- e^+ \rightarrow e^- \bar{\nu}_e t \bar{b} $ at LEP~200. The
results reproduce roughly those obtained earlier by using the equivalent real
photon approximation and we confirm the observation that detecting a top
heavier than half the c.m.~energy is not feasible at LEP~200. The calculation
has been performed by a new automatic Feynman amplitude generator MadGraph
which produces HELAS code for the helicity amplitudes.
