Newfoundland Air Mails
Newfoundland was the starting point for most of the early attempts to fly the Atlantic. The Postmaster-General of Newfoundland arranged for a limited amount of mail to be carried on many of these flights, and issued a number of overprinted stamps for them. Many of these stamps and covers are now very rare and expensive.
There were also a number of attempts to establish internal air mail services in the 1920's and 30's, but none of them were successful.