Errors in the dates


Another set of design errors covers the non-respect of dates. In most of the instances, those errors were introduced by a misunderstanding of the ICAO anniversary dates. The latter Organization left much confusion on its anniversary dates, celebrated as follows:



Celebrated on

10th Anniversary

June 1955

15th Anniversary

4 April 1962

20th Anniversary

7 December 1964

30th Anniversary

4 April 1977

35th Anniversary

4 April 1982

40th Anniversary

7 December 1984

45th Anniversary

7 December 1989

50th Anniversary

7 December 1994

60th Anniversary

7 December 2004

65th Anniversary

7 December 2009

70th Anniversary

7 December 2014

75th Anniversary

7 December 2019


Moreover, the designers of some stamps included in their project the ICAO emblem with the indication of 75o Aniversario de OACI or 75th anniversary of ICAO. Belize, Paraguay and Uruguay inadvertently confused the 75th anniversary of the Wright brothers’ triumph (in 1978), who made the first successful flight of a manned heavier-than-air vehicle on 17 December 1903, with ICAO which, even today, has not yet reached its 75th anniversary.


Canada – 1 June 1955

10th Anniversary of the interim Agreement and first PICAO Meeting

First Day Cover – H. & E. raised cachet; designed by Hearl Grasiadei

The text in the cachet (INT. CIVIL AVIATION Organization Conference) is confusing; it seems to refer to the Chicago Conference, for which 1955 would not be a major anniversary. So, it could be considered as an error in the dates. It would have been more appropriate not to print the word Conference in this cachet.


United Nations - 20th Anniversary of ICAO - First Day Cover

Strangely, the postmark is dated 8 December 1964, instead of 7 December 1964.



Cameroon (15 March 1967) and Gabon (19 April 1967) - 20th Anniversary of ICAO

These countries calculated the 20th anniversary on the basis of the constitution of the new permanent International Civil Aviation Organization (ICAO) on 4 April 1947, when ICAO celebrated this anniversary on 7 December 1964.


Barbuda – 24 May 1979 - 30th Anniversary of ICAO

This cover seems to commemorate the 30th anniversary of ICAO; the year 1949 does not correspond to any major reference date (such as 1944, 1945 or 1947) from which ICAO anniversaries could be counted. It should have more rightly commemorated the 35th anniversary (1944-1979), as indicated in the stamp catalogues.

However, one indication could be that Barbuda took, as reference date, the occupation of the first permanent accommodations (International Aviation Building) at 1080 University Street, Montreal, at the corner of Dorchester (now Boul. René-Lévesque) and University Street, ready for occupation by 15 July 1949. A second indication for this commemoration of a 30th anniversary could be that Barbuda took into consideration the first official meeting of the Air Navigation Commission (ANC), which took place on 7 February 1949. These two events may have triggered the commemoration of the 30th anniversary of ICAO by Barbuda; but the year 1949 was not actually an anniversary date celebrated at ICAO.

It is interesting to note that Barbuda was not a Contracting State of ICAO when this set of stamps was issued in 1979. Antigua and Barbuda became a Member of ICAO on 14 November 1981.


Uruguay – 18 June 1979

Anniversaries and Events: 75th Anniversary of first powered flight and

65th Anniversary of the Uruguayan air force.

75th anniversary of ICAO!




Belize – 30 July 1979

100th Anniversary of Sir Rowland Hill death and

75th anniversary of the first powered flight

75th anniversary of ICAO!



Paraguay – April and June 1979

75th Anniversary of aviation and 100th Anniversary of Sir Rowland Hill death

75th anniversary of ICAO!



Democratic People’s Republic of Korea – 26 December 1980

75th Birth Anniversary of Dag Hammarskjöld, second Secretary-General of the UN

During his fourth trip to encourage national reconciliation and to end foreign interference in Congo, Dag Hammarskjöld boarded on the night of 17 September a flight (on the “Albertine”, a DC-6B airplane belonging to the Swedish Transair Company) to Ndola, Northern Rhodesia (now Zambia) to meet Mr. Tshombé, the provincial president of Katanga and seek an end to fighting in secessionist Katanga. On its final approach, the plane crashed; Dag Hammarskjöld was killed, along with seven other UN staff members and the Swedish crew of eight. The time of the crash, established by the stopped watches of the passengers, was between 10:00 and 10:13 PM GMT on 17 September 1961; as Rhodesia is two hours ahead of GMT, the crash was reported on 18 September local time. The above souvenir sheet indicates the day of Dag Hammarskjöld’s death as 17th September.



Guatemala – 2 April 1987 - 40th Anniversary of ICAO

This country still calculated ICAO’s 40th anniversary on the basis of the constitution of the new permanent International Civil Aviation Organization, ICAO, on 4 April 1947, although, since its fortieth anniversary, ICAO had decided to use the ending date of the Chicago Conference, i.e. 7 December 1944.