International Airlines
International Airlines' Western Air Express service operated during August and September 1933 between Croydon, Portsmouth, Southampton and Plymouth. The airline operated a short-lived airmail service for an additional fee of 3d, however, the service was unofficial and contravened the Post Office monopoly. Covers with a yellow label were carried on the first flight on 25th August, but due to bad weather at Plymouth the aircraft was unable to land and returned to Portsmouth, flying on to Plymouth the next day. A flight was also made from Plymouth to Croydon on the 24th August by some of the company's directors, who carried covers which were posted on arrival. Covers were also carried on 26th August and 1st September. The service was not widely advertised and did not last.
25th August 1933. Western Air Express.
Sheets of 20. Perf.: 11 except on margins.
No Value
Black on yellow paper.

International Airlines Western Air Express Air Mail Magazine Volume 1, pp. 29-30, A. Phillips (1939)
The Air Mails of the British Isles Chapter 3, H. Stanley Redgrove, Privately Printed, (1940)
The Story of the Airway Letter Service 1933-1988 D. Wilson, Air Mail News June 1994