North Central Airlines  Convair 340-35    N90858                      (c/n  83)

                              

                                   In 1959 North Central, in looking to upgrade its fleet, purchased five Convair 340s from Continental
                                   Airlines.  These were upgraded (probably by General Dynamics, one at a time) to Convair 440 status,
                                   and it is in that condition that we see N90858 in this shot by Leo J. Kohn above.  Locale was Billy
                                   Mitchell Field, Milwaukee, circa 1961.   In the mid 1960s the airline purchased another ten of these
                                   aircraft from various sources and all were converted to CVAC 440 status initially, and later further
                                   modified to Convair 580 configuration.