Experimental Airmail UK - Australia

In April 1931, Imperial Airways planned two experimental airmails from London to Melbourne and return. This was the first official air mail between Great Britain and Australia.

Letters could be addressed to New Zealand and were accepted in New Zealand for the two return flights from Australia. Carriage between Australia and New Zealand was by sea. A major reason for the flight was that the Dutch had already established an air route from Amsterdam to the Dutch East Indies and were planning a flight to Australia.

First Experimental Flight

UK to Australia/NZ

To New Zealand 31

The example registered letter is postmarked Birmingham on 2 April 1931 and is addressed to New Zealand.

To New Zealand 31 back

The postage rate for the flight was 1s 4d per ½ oz. The letter has stamps to the value of 1s 7d which includes 3d for the registration fee.

To New Zealand 31 To New Zealand 31

The next cover is franked with the required 1s 4d with all three stamps being GV controls.

It has a different 29 April Sydney backstamp from the first cover.

The first Imperial Airways flight left Croydon Airport (London) on 4 April on the regular Imperial Airways service to Karachi and Delhi. There were Qantas services from Brisbane and an Australian National Airways (ANA) service from Brisbane to Melbourne. The plan was to connect these services with Imperial Airways flying from Delhi to Darwin and Qantas from Darwin to Brisbane.

The schedule was to arrive in Australia on April 20, but the backstamp shows that Sydney was not reached until 29 April. The New Zealand mail was sent from Sydney to Wellington on the Maunganui from 1-5 May [6].

The Route


Karachi to Darwin

The route from London was by an AW Argosy via Cologne and Vienna to Skoplje from where the mail was sent by train to Salonica. The next stages were by Short S8 Calcutta flying boat from Salonica to Alexandria where it arrived on 8 April.

The DH 66 Hercules City of Delhi flew from Cairo to Karachi on 9 - 12 April and then from Karachi to Delhi on 13 April where the mail was transferred to a second DH 66 (the City of Cairo) which flew on to Allahabad [4].

London - Calcutta


On 14 April, the mail was flown from Allahabad via Calcutta to Akyab. This cover from London to Calcutta is backstamped at 11.30 on the morning of 14 April and again at 2pm.

The rate from London to India was 1s 0d.

Delhi - Victoria Point
Delhi - Victoria Point

On 15 April, the mail was flown from Akyab via Rangoon to Victoria Point in Southern Burma. This postcard was flown from Delhi to Victoria Point. It is postmarked Civil Aerodrome Delhi on 13 April. Although there was an overnight stop, apparently the mail for Victoria Point was off loaded in Rangoon and sent on by surface. This card has a Victoria Point handstamp on 22 April which is when it eventually arrived there [5].

On 16 April the mail was flown from Victoria Point via Alor Star in Kedah to Singapore. The mail left Singapore on the 17th for Samarang in the Dutch East Indies and then to Sourabaya on 18 April.

Crash at Koepang

The City of Cairo crashed at Koepang (Kupang) in Timor in the Dutch East Indies on 19 April.

ANA were contacted and Kingsford Smith, with G U Scotty Allan as co-pilot, flew the Southern Cross from Sydney to Koepang on 21-24 April. They picked up the mail and flew it from Koepang to Darwin on 25 April. The mail was flown from Darwin to Brisbane by Qantas in a DH 61 Giant Moth on 27-28 April and by ANA from Brisbane to Sydney on the Avro Ten Southern Sun on 29 April. Later on 29 April, mail was flown from Sydney to Melbourne by Jim Mollison in the Southern Star. (Three months later Mollison set a new Australia to England record time of 8 days 19 hours.)

The New Zealand mail was forwarded from Sydney by sea on the Maunganui and arrived on 5 May, 31 days after leaving London.

Return of First Experimental Airmail

NZ/Australia to UK

The flight for London left Melbourne on 23 April with the mail from New Zealand being sent from Wellington to Sydney on the Ulimaroa on 17 - 21 April [6] and joining the flight at Sydney on 24 April.

aus 31

Only 229 ordinary and 106 registered letters were sent from New Zealand.


One of the registered letters is shown. It is postmarked Auckland on 16 April. The cover carries 2s 6d postage including two GV 7½d stamps perf 14 x 14½, the rarer perforation! The postage is made up as follows: 2s 0d air mail to Great Britain plus 2d ordinary postage and 4d registration fee. The surface rate and registration fee had been increased on 1 March, 1931. (They were reduced back to 1d and 3d respectively on 1 June 1932.)

The cover is backstamped 21 April in Sydney when a special cachet was applied. There is no UK backstamp despite the cover being redirected. (No doubt in an attempt to get a backstamp.)

to Karachi

The second cover from New Zealand is addressed to Karachi. The airmail to India was 1s 3d plus 2d ordinary postage.


It arrived in Karachi on 5 May, but was not backstamped until 6 May. The cover has Kingsford Smith's signature (although it appears to be a fake).

aus 31

The next cover is only franked with stamps to the value of 9d which was the cost of sending a letter from New Zealand via the Karachi - London airmail (7d air mail plus 2d surface). and far less than the cost of the flight from Australia.

However, it has the routing instruction via Darwin Australia to England Air mail Service and as it has the special Melbourne cachet on the back, it appears to have been flown on the experimental airmail.

The route

The New Zealand mail was carried by Australian National Airways from Sydney to Brisbane on the Southern Sun on 24 April and then by Qantas in a DH 61 from Brisbane to Darwin, on 25 - 26 April.

The plan had been for the Imperial Airways DH 66 to fly the mails from Darwin, but as it had crashed at Koepang on the 19th and Imperial Airways had no replacement aircraft, Kingsford Smith and Allan, who had arrived in Darwin from Koepang on the 25th, flew the mail from Darwin to Akyab in Burma on 27 April - 3 May.

At Akyab, the mail was transferred to the Imperial Airways DH 66 City of Karachi on 3 May and flown to Delhi, arriving on 5 May. From Delhi it joined the regular Imperial Airways flight to London where it eventually arrived on 14 May, 27 days after leaving New Zealand.

Official covers

aus 31

Official covers were available in Australia, but none are known from New Zealand. A cover, posted in Sydney, is shown. The special flight cachet is on the back.

aus 31

Part of the inscription on the cover is obscured by the stamps and reads: "ALL THE WAY BY AIR" Royal Mail Service from Australia. The cover has the full set of the Kingsford Smith commemoratives which had been issued a month earlier on 19 March. Given Kingsford Smith's part in the flight, their use is particularly appropriate.

aus 31

Imperial Airways also produced an official cover and it was used both for flights to and from Australia. The shown cover is postmarked Darwin on 26 April and was flown (27 April - 3 May) on the first part of its journey (to Akyab) by Kingsford Smith and Allan.

Picking up mail

Mail was picked up along the route.

a) at Rangoon

This cover is postmarked Rangoon 28 April and was flown from there to Akyab by Kingsford Smith on 3 May.

Later on 3 May, it was flown from Akyab to Calcutta by Imperial Airways in the DH 66 City of Karachi.


It has a First Airmail purple cachet that was applied to all mail that was picked up from or delivered to Rangoon. The cover was backstamped on arrival in London on 14 May.

Stephen Smith cover
c) at Calcutta

The next cover was flown from Calcutta on 4 May, and is addressed to the UK.


It is backstamped Huddersfield on 15 May which fits in with the arrival at Croydon airport on 14 May.

The cover was produced by Stephen Smith who was responsible for many covers from India in the 1930s. His signature is on the back.

Calcutta - Delhi
b) Calcutta to Delhi

The next cover was also flown from Calcutta, but only as far as Delhi.


The red cachet on the front is unclear but states: First Air Flight / Australia - England / Delivery / Delhi 4-5-31.

However, the plane was behind schedule and was flown from Calcutta to Allahabad on 4 May and from there to Delhi on 5 May as shown by the Delhi backstamp. 123 covers were carried on the Calcutta - Delhi leg.

From Allahabad
d) Allahabad to Delhi

The next cover was flown from Allahabad to Delhi. It was postmarked in Allahabad on 2 May 1931 and was flown from Allahabad to Delhi on 5 May. It was not backstamped.

The red cachet on the front was applied in Delhi and states: First Air Flight / Australia - England / Delivery / Delhi 4-5-31. However, the plane was behind schedule and so was not flown to Delhi until 5 May.

Second Experimental Airmail

Second to Calcutta
UK to India

The second experimental airmail left London on 25 April and was flown on the regular Eastern Route to Delhi arriving on 4 May. The total mail for Malaya, Australia and New Zealand was 5000.


The DH 66 Hercules City of Karachi had arrived in Delhi on 5 May from Akyab with the mail from the return flight of the first experimental airmail. The mail was exchanged and the City of Karachi immediately returned that day (via Allabad) to Calcutta.

This cover is franked with 8d and was flown to Calcutta where it arrived on 5 May and was backstamped at 7am on 6 May. It is addressed to Stephen Smith, a well-known aerophilatelist, and I think that he applied the purple cachet.

Second to New Zealand
UK to New Zealand

The mail was flown from Calcutta to Akyab on 6 May and was then flown from Akyab to Darwin from 6 to 11 May by Kingsford Smith and Scotty Allan in the Southern Cross. (Akyab - Rangoon on 6 May, to Alor Star on 7 May, to Singapore on 8 May, to Sourabaya on 9 May, to Koepang on 10 May and to Darwin on 11 May.) From Darwin it was flown to Brisbane on 12 -13 May in a DH 50 by Qantas and then by ANA to Sydney on 14 May in the Southern Moon with P G Taylor as pilot. Sydney - Melbourne was later on 14 May on the Southern Sky.

Second to New Zealand

This cover is postmarked in London on 24th April and is addressed to New Zealand. It was flown on the second flight and the postage rate was again 1s 4d.

The cover was offloaded in Sydney on 14 May where it was backstamped and sent to New Zealand by sea. The mail arrived in Wellington on the Maunganui on 18 May, 23 days after leaving London and this cover is backstamped in Christchurch on 19 May.

Return of Second Experimental Airmail

Return flight, acceptance from New Zealand

There were 266 acceptances from New Zealand for the second return flight and they were sent from Auckland to Sydney on the Maunganui on 8-12 May 1931 [6]. The cover is postmarked Christchurch on 6 May. As with the first return flight, the postage rate was 2s 2d made up of 2d ordinary postage and 2s 0d airmail fee.

The flight left Melbourne on 15 May and the New Zealand mail joined at Sydney on 16 May. The Melbourne - Sydney - Brisbane leg was flown by ANA in the Southern Sun with Jim Mollison as pilot.

Qantas flew the leg from Brisbane to Darwin on May 17-18. The pilot was Hudson Fysh in a DH 50. He was Managing Director and co-founder of Qantas and this was the last time he flew a scheduled service. The cover has his autograph.

By this time, Imperial Airways had purchased a replacement DH 66 and it flew the leg from Darwin to Delhi (May 19 - 26).

The mail arrived in Singapore on 22 May where the DH66 remained overnight.

Singapore - Alexandria

This cover is postmarked 21 May and was flown from Singapore on 23 May. It is addressed to Alexandria in Egypt and has a Cairo backstamp on 30 May and an Alexandria backstamp on 31 May.

It is re-addressed to London to where it was presumeably carried by surface.

As well as the ordinary Singapore postmark, a special backstamp was applied in Singapore.


Unfortunately, in this example, it is largely obscured by the Alexandria backstamp of 31 May. However, it is possible to make out the date of 22 May together with the slogan Imperial Airways Ltd London - Australia Air Mail on four lines.

from Alor Star

The next cover is postmarked at Penang on 21 May and joined the flight at Alor Star which was reached on May 23.

It is addressed to London and has franking of 48c while the previous cover to Egypt only has franking of 37c.

The mail connected with the scheduled flight from Delhi on May 27 and was flown to Cairo where it arrived on 30 May.

The route from Alexandria on May 31 had recently been changed and was now by Short Kent flying boat to Genoa where it was due to arrive on June 1. However, the flight was delayed for two days in Corfu [4] and so it was June 3 before it arrived in Genoa. The mail was sent by overnight rail from Genoa to Basle and then flown to London where it arrived on 4 June [3, 4]. That corresponds with the Sutton Coldfield ½d paid mark of 5 June on the cover from New Zealand.


22c 60c

The 50th anniversary was commemorated in 1981 by the issue of two Australian stamps depicting a 1931 stamp issued to commemorate the flights of Charles Kingsford Smith. However the 1931 stamp had nothing to do with the Australia-UK airmail. It was issued on 19 March 1931, i.e. before the airmail flight took place.

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All scans were made by the author. Information on this page is taken from:
[1] Airmails of New Zealand, volume 2 (1986) compiled by Douglas A Walker
[2] The New Zealand Airmail Catalogue, (2nd Edition, 1994) by James Stapleton.
[3] The Postal History of British Air Mails, E B Proud, 1991.
[4] Aircraft Movements on Imperial Airways' Eastern Route, Vol 1, 1927 - 1937, Peter Wingent, Winchester 1999.
[5] The 1931 Imperial Airways experimental airmail flights, E. Wolf, Imperial Airways Gazette, Issue 30, pp 2-18, December 2006.
[6] Evening Post Wellington 1916-1945, Papers Past, available at: paperspast.natlib.govt.nz/cgi-bin/paperspast