The calculated distance (air line) between Downsview-Roding-CFB and Oakville is approximately 22 miles respectively 35 kilometers.
By car or train, the actual journey to Oakville is certainly longer, as only the direct route (as the crow flies) between Downsview-Roding-CFB and Oakville has been calculated here.
Air line (approximately)
35 kilometers
19 nautical miles