Both the Model 200 and the Model 221 were eventually modified for transcontinental service as the Model 221A, with slight fuselage stretches to give both a cabin for eight passengers.
Tanto o Model 200 como o Model 221 foron finalmente modificados para realizar servizos transcontinentais baixo a designación Model 221A, estendendo a fuselaxe para poder levar 8 pasaxeiros.