Calculated Electron Fluxes at Airplane Altitudes

A precision measurement of atmospheric electron fluxes has been performed on a Japanese commercial airliner (Enomoto, {\it et al.}, 1991). We have performed a monte carlo calculation of the cosmic ray secondary electron fluxes expected in this experiment. The monte carlo uses the hadronic portion of our neutrino flux cascade program combined with the electromagnetic cascade portion of the CERN library program GEANT. Our results give good agreement with the data, provided we boost the overall normalization of the primary cosmic ray flux by 12\% over the normalization used in the neutrino flux calculation.