These Christmas mail flights were very special events. The 1933 flight was planned to use the new Fokker F.XX PH-AIZ 'Zilvermeeuw' but when that one developed engine trouble on the morning of the planned departure the F.XVIII PH-AIP 'Pelikaan' was quickly substituted. Within the three days that the Pelikaan took to reach Indonesia new covers were printed with the name of the Pelikaan on them for the return flight. Examples are shown on this page: Pelikaan | Snipfan.nl

The first cover is marked 'Zilvermeeuw' with a misspelled 'Pelikaan' quickly typed underneath. The fifth image shows the new cover, now with the name of the Pelikaan on it and it looks like the postmarks also all have the name Pelikaan on them. It makes me think that they may already have had stamps available for the different aircraft that flew the route.

It is impressive to see that envelope from the Uiver. I can understand that it must have been strange to hold that envelope knowing its history.

Sounds like a dry run for the 1938 UK Christmas mail fiasco along the same route to the Far East and Australia. As well as the regular Empire Flying Boats, three of the latest new 4-engined wonderplane Armstrong Whitworth Ensign were to carry the eagerly awaited, and expensive, Christmas greetings. They set off from Croydon well covered by the press. One broke down at Athens, another got as far as Alexandria in Egypt, while the third actually got as far as India. But not beyond.

Older aircraft had to come to the rescue. The Ensigns were sent back to Armstrong Whitworth in disgrace.

The 30¢ and 6¢ stamps on my Uiver envelope are equivalent to about £3 today. Expensive, even before any fee for purchasing the Christmas air letter.