Impossible. Flying aircraft are cosidered to be on a different 'layer' than ground/naval objects, which usually have cloak abilities. Docked aircraft, however, can detect cloaked objects. However, I do believe the code should be Sensors=yes instead of HasSensors=yes,
Buildings used to be able to have sensors in RA2 but they were taken out by Yuri's Revenge (either in a RA2 patch, or YR, or YR 1.001 - not sure when building sensors stopped working).