Charles Marinus Sundby was one of the Danish officers, who escaped occupied Denmark in 1940 to join the Allied air forces. He joined the Royal Canadian Air Force serving as a flight instructor for a year and a half, before serving as a ferry pilot on the Atlantic. In late 1942, he joined the China National Aviation Corporation and flew more than 600 transport sorties from India to China over the Himalayas. He was killed in a flying accident in 1948.
Charles Marinus Sundby was born on 15 November 1908 in Valby, Copenhagen, to Jens Marinus Jensen Sundby and Anna Kathrine Sundby (nee Gerdt).
He began his career, not as a pilot, but in the merchant marine, signing on to his first ship in 1925, and in 1930 he had earned the experience required to be admitted to navigation school for officer training. In 1933, he graduated, having passed the master’s examination, and a year later he passed the master’s certificate exam.
That same year, the admission requirements to the Naval Air Service had been changed to accept men holding the master’s examination, and so Sundby was accepted for pilot cadet training, joining the class of 1934. He was commissioned as an officer on 21 December 1935. From 1936 to 1940, he served in the Naval Air Service and took part in several expeditions to Greenland, the Faroe Islands, and Spitsbergen (Svalbard). He was about to be transferred to the reserves in September 1939, but instead remained on active service due to the outbreak of war in Europe.
Escape from Denmark
On 9 April 1940, as Germany invaded Denmark, Sundby was on duty as the Germans took over the Naval Air Station in Copenhagen. Among the other pilots on duty was the later Wg Cdr Kaj Birksted. As late as on the 6th, Sundby had carried out a mine reconnaissance operation in Danish waters, but on that morning all aircraft remained in the water. Birksted and Sundby both felt humiliated by the surrender. Now they had to share the mess with the occupying Luftwaffe officers. The two pilots had not been close until then, but they would soon unite in the desire to continue the fight against the Germans in Norway.
On the night of 16–17 April, they escaped to Sweden in one of the air station’s motor launches. In Sweden, they were detained by the police, but they were, eventually, allowed passage to Stockholm.7 From Stockholm they travelled to Namsos, where the Norwegians were still fighting, supported by the Allied expeditionary force. Birksted and Sundby were engaged as liaison officers with the British forces on-board the destroyer HMS Wolverine. Between 6–7 May, the British forces evacuated Norway. Birksted and Sundby arrived in
Glasgow, presumably on-board the Danish ship SS Gunvor Mærsk on 7 May, and continued on to London, where they arrived the following day. They immediately applied for service in the RAF and—at least in the case of Sundby—in the BOAC. They were both turned down. Determined not to give up, they were engaged on the Danish ship M/S Tasmania bound for Burma. Arriving in Cape Town, they applied for service in the South African Air Force (SAAF), but they had to continue to Calcutta before receiving the final reply. In Calcutta, they learned that they had been accepted for service in the SAAF, and so they returned to Cape Town. En route, they learned that they had been accepted by the Norwegian Air Forces as well. The Norwegians were setting up a training camp in Toronto, Canada. Birksted and Sundby arrived in Canada in October 1940; Birksted enlisted in the Norwegian Air Force, while Sundby enlisted in the Royal Canadian Air Force.
Sundby was accepted into the RCAF as Flying Officer (C.3000) in October 1940, and promoted to Acting Flt Lt on 11 November 1941. From March 1941 to February 1942, Sundby served as an instructor at 13 (Operational Training) Squadron in Patricia Bay, British Columbia. He then joined the RAF Ferry Command, delivering bombers on both the northern and southern routes from May to October 1942.
China National Aviation Corporation (CNAC)
As early as 1937, the conflict between Japan and China had developed into the Second Sino-Japanese war. The Japanese aggression was a threat to the strategic interest of Britain, France, the United States, and Russia. Even if the four countries did not share a common strategic interest, they were united in supporting the Chinese war effort both directly, in terms of weapons and military advisors; and indirectly, by providing access to roads, railways, and harbours.
By 1941, the Burma road was the last major supply line into China. The 717-milelong road running through the mountainous border regions connected Lashio in Burma with Kunming in China. The Burma road became a major strategic objective for the Japanese. In May 1942, the rapidly advancing Japanese forces reached the road, and thereby cut off supplies to the Chinese forces as well as to the American Volunteer Group—the Flying Tigers—in Kunming. The Allies, therefore, had to look into alternative ways of getting supplies into China. The solution was provided by the China National Aviation Corporation (CNAC), a privately owned American–Chinese airline. As early as November 1941, CNAC had demonstrated that it was possible to cross the Himalayas from India to China in a Douglas DC-3—therefore it was also possible, albeit dangerous, to supply China by air. CNAC, which had been partly owned by Pan Am since 1933, was a pioneer in commercial aviation in China.
In 1937, when the Japanese invaded, the company had an extended route network in the country, and, despite the war, CNAC succeeded in maintaining a well-run airline in the region until the outbreak of the Second World War. However, it was one thing to cross the Himalayas. Supplying an entire army by air was a completely
different story. Opinions on the feasibility of the operation were divided at the time. The reality was that it had never been done before; furthermore, neither the RAF, nor the USAAF had the number of aircraft needed in May 1942. As a consequence, the initial plan for the operation was for CNAC to operate the route under contract. CNAC begun full-time service on the ‘Hump Route’, as it was nicknamed, in July 1942. The company remained essential to maintaining an effective airlift on the route throughout the war, even as the USAAF expanded their capacity on the route, partly due to the crews’ greater experience.
Sundby was the only Dane flying the Hump Route. He signed a contract with CNAC in Miami on 10 November 1942; in an interview after the war, he said that he joined as he needed a change. He was employed as a co-pilot, effective from 4 November 1942. According to the contract, CNAC reserved the right to limit his assignment to ‘[…] a period governed entirely by [his] demonstrated ability and qualifications to be in command of an aircraft flown over any of the routes which CNAC operates.’ On successful completion of a four-month trial period, he would be promoted to first pilot.
When Sundby arrived in India in December 1942, he was a very experienced pilot with a total of 1,750 flying hours.
Sundby left the United States on 19 November 1942 and arrived in Calcutta, where CNAC headquarters was located, on 3 December. Arriving in Calcutta, Sundby probably met with William McDonald, who was assistant to CNAC’s Chief Pilot, and the Check Pilot Captain Robert Pottschmidt. He was most likely introduced to the company aircraft and procedures before flying to Dinjan for advanced training as a co-pilot on the Hump Route. This training included learning the different routes and becoming familiar with the weather conditions over the Himalayas. After completing the training programme, he had to be checked out as a captain.
Sundby carried out the first two flights to China on 11 December 1942. From Balijan, near Dinjan in Assam, he crossed the Himalayas and landed in Kunming, returning the same day. Sundby repeated the flight over the following days, and on the fourth day, he operated as first pilot for the first time. On 21 December, he flew to Calcutta to be checked out. He performed test flights with McDonald and Pottschmidt until 26 December 1942. An experienced pilot was able to be checked out within a few weeks from arrival, while the average was two to three months. Sundby was checked out as a captain only two weeks after his first flight on the Hump; once again, his experience seemed to pay off. Sundby returned to Dinjan on 27 December and flew back and forth to Kunming from Balijan almost every day until 16 January 1943. The aircraft were Douglas C-47 and C-53, the latter being a variant of the C-47 adapted for troop transportation. From 18 January to 8 February he was ‘downcounty’, that is, in Calcutta for a well-deserved leave. Over the next year and a half, Sundby operated continuously in the area, primarily over the Hump, only interrupted by short periods of leave in Calcutta.
On an average working day, Sundby would take off from Dinjan or one of the other airfields in Assam, and then set course through the Brahmaputra valley. On the border between India and Burma, the aircraft would pass the Paktai mountains, reaching a height of approximately 10,000 feet. He would then cross the upper Chindwin valley and the Kumon mountains. Then followed a series of 14–16,000 feet high mountain ranges separated by the West Irrawaddy, East Irrawaddy, Salween, and Mekong rivers. These were a prelude to the real Hump: the Satung mountain range’s 15–20,000 feet high peaks. After the Mekong River, the country leveled out on the way to Kunming. In an interview in 1946, Sundby explained:
We carried Chinese soldiers who were to be trained in India. It was a distance of 510 miles. Because the Japanese held Burma, it was necessary to fly a detour, and this route went from the province of Kunming to Assam in the northeastern part of India near the rise of the Bramaputra river. […] The route we flew, [was] reasonably secure. […] We lost only two machines because of Japanese action, while weather conditions were the cause of a loss of nearly 30 transport aircraft.
Even if the route was relatively secure from Japanese fighters, it was still dangerous flying. In his logbook, Sundby recorded lost aircraft and crew during his time in CNAC. From 10 March 1943 until 28 January 1947, he recorded forty-two aircraft lost, in most cases without survivors. Only two of these losses are believed to have been caused by enemy action. One aircraft was confirmed shot down on 13 October 1943, while another was believed shot down on 14 Defending an Empire: India, Burma, and China (1941–45) 189 September 1943. The latter incident led to CNAC conducting Hump flights at night for a long period in order to avoid the threat of Japanese fighters.
On 15 May 1944, Sundby left India on leave in the United States. According to his travel order, the purpose of the trip was to ferry an aircraft from the United States to China on behalf of CNAC. He arrived in Miami, Florida on 25 May 1944, and went on to San Francisco to stay with his brother, returning to India after two and a half months. Sundby returned to Dinjan and continued flying operations again on 24 October 1944. This turned out to be one of the busiest periods for him throughout the war: in December 1944 alone, he flew a total of forty-three flights in fifteen flying days. Sundby’s logbook indicate that he began flying scheduled services between Calcutta–Dinjan–Kunming at this point. From Kunming, he often shuttled to other cities in China. The high level of activity during this period is probably connected to the situation on the Burma front—from 15 October to 20 January, the Chinese Y-force was advancing on Burma along the Burma Road from the Yunnan province in China. The fact that some of Sundby’s flights were to airfields between Myitkyina and Kunming supports this. Sundby continued operations until mid-December 1945, at which point he departed on leave to Denmark. Until the end of the war in August 1945, he had carried out another 383 flights, of which 140 had been Hump flights. During this period, the number of flying days per month was lower than in earlier periods, while the average flying hours per flight was higher. From his first trip over the Hump on 11 December 1942 to his last Hump flight exactly three years later, he logged 2,488 hours of flying with CNAC and made 591 flights over the Himalayas between Dijan/Balijan and Kunming.
A Tragic Accident
Sundby remained in CNAC after the war, flying in a China marked by political uncertainty. On 21 December 1948, he was the pilot of a DC-4 (XT-104), flying American refugees from Shanghai to Hong Kong. The aircraft crashed in bad weather on the approach to Hong Kong’s Kai Tak airport, and all aboard were killed. Sundby’s urn was received with a military honour guard in Copenhagen on 2 September 1949.
This text has been compiled with the help of Charles Sundby's daughter, who has also written a more comprehensive account found for www.cnac.org. The Charles M. Sundby archive of documents and photos, along with a more extensive biography and a fuller account of the Basalt Island crash, has been donated by his daughter to the Aviation Library & Louis A. Turpen Aviation Museum at the San Francisco International Airport.
 DNA: Parish register, Valby Sogn.
 Travel documents and letters from the Sundby family.
 Sundby’s personal documents, logbooks and correspondence (the Sundby family).
 Peattie and Drea, The Battle for China (2011), p. 283–288.
 Willett, An Airline at War (2008), pp. 140–142.
 Leary, The Dragon’s Wings (1976), p. 142.
 Koenig, Over the Hump: Airlift to China (1972), pp. 30–32.
 Spencer, Flying the Hump (1994), p. 70.
 Sundby’s contract, signed 11 November 1942.
 Leary, The Dragon’s Wings (1976), p. 169.
 Koenig, Over the Hump: Airlift to China (1972), p. 51.
 ‘Danskeren, Der blev Chefpilot for den Kinesiske Regering’ in Flyv (1946), quote translated by author.
 Sundby’s personal documents, logbooks and correspondence (the Sundby family).
 www.cnac.org, Stars and Stripes.