A former Danish Army Corps pilot, Sigfred Johannes Christophersen evades Denmark with Jørgen Thalbitzer in the end of 1940. He is trained by the SIS as agent and is sent to Denmark with Thomas C. Sneum in late 1941. Evacuated from Denmark he joins the Royal Air Force. He is tragically killed during a night exercise in August 1943.
Sigfred Johannes Christophersen is born on 11 July 1914. He is the son of market gardener Johannes Ruder Christophersen and Ane Cathrine Christophersen (née Paaskesen). He is – but I have no trace of a connection between them – born in the same parish as Eigild Ramsdahl Rohde just three days apart. 
Trained as Pilot
He joins the Danish Royal Guards in November 1935, but is accepted for flying training at the Army Flying School from 1 April 1937 (pilot's certificate 212/1937). 
He is discharged from the school on 10 September 1938 and is unemployed for the next six month. He then spent some time working in Germany as a gardener. In January 1940 he volunteers to become a pilot in the Finno-Russian Winter War, but it is not clear if he actually was engaged in operational duties before the end of hostilities in March 1940. He returns to Denmark and works for a while at the German occupied Værløse Air Station. 
On 26 December 1940, he leaves Denmark accompanied by Jørgen Thalbitzer, who is later to become fighter pilot and who is killed in 1943, while in Royal Air Force service. They travel to Istanbul, Turkey, and from here to Cyprus, Suez, and Cape Town to London. They arrive in London on 23 April 1941. 
Christophersen and Thalbitzer volunteer for the Royal Air Force at the British Air Attaché in Istanbul. But in London Christophersen accepts an offer by British Intelligence to be trained in radio-telegraphy. Without knowing it at the time he has been enrolled in the Special Intelligence Service (SIS) 
He is coupled with Lieutenant Thomas Christian Sneum to be sent to Denmark as British agents.
On 10 September 1941 at 1946 hours a Whitley of No. 138 Squadron captained by F/Sgt A.W. Reimer (R.61467) takes off from Newmarket bound for Denmark. On board are Sneum and Christophersen also known as Esmond and Columbus. The aircraft crosses the Danish coast near Esbjerg, and flak is encountered. Target is reached at 2335 hours and the two agents are successfully dropped near Holbæk. An attempt to drop the agents the night before had been aborted due to clouds and heavy rain. 
Sneum and Christophersen never succeed together as agents, since they never really get to trust each other. According to different sources Christophersen seems to be the one to blame. In the end of February 1942 Christophersen is so compromised that he is ordered to leave the country by Sneum.
On the night of 3-4 March 1942, Sigfred Christophersen attempts to cross the ice covered waters between Stevns in Denmark and the peninsular Falsterbo in Sweden. He is accompanied by his brother Thorbjørn Christophersen and another member of the resistance Kaj Oxlund. Due to bad weather Sigfred Christophersen is the only one to barely survive the crossing being picked up by Swedish fishermen.
He is imprisoned in Malmø, Sweden, and interrogated by the authorities. During the interrogation he reveals many details on his whereabouts and activities in Denmark. This combined with the fact that Kaj Oxlund's name is revealed by his death compromises Sneum who is still on the ground in Denmark. Both agents had used Oxlund's flat as hideout. Sneums flees Denmark in the end of March 1942.
In mid-June 1942 Christophersen, Helvard and Sneum are transferred to England via Bromma and Leuchars in a Lockheed Hudson. They are imprisoned in the Brixton Prison at the arrival. 
In Royal Air Force service
Released from Britain Christophersen commences pilot training in the Royal Air Force. As Christophersen's and Thalbitzer's service numbers as NCOs are next to each other it is clear that he actually was accepted for Royal Air Force in 1941 at the same time as Thalbitzer. No he returns for pilot training.
Tragically, he is to loose his life while in training. I have few information on his training. On 25 January 1943 he is in training in Canada at No. 38 Service Flying Training School, Estevan, Sakatchewan. He is then Leading Aircraftman. 
On 10 August 1943, he is killed in a training accident. On a night exercise, he is the pilot of Blenheim Mk. I (K7050) from No. 12 (P) Advanced Flying Unit. Loosing sight of the flair path for the aerodrome he tries to land at a Q site, but cannot control the aircraft that crashes and burns out completely near Buttesford, Leicestershire, at 0135 hours. The crew of three is killed. 
Sigfred Johannes Christophersen is buried at Grantham Cemetery. Just a short time before his death he is married to Mary Anita Blackford Wood. 
- Parish record of Horsens Klostersogn
- Clauson Kaas, 1943, Ryan, 2008
- Ryan, 2008
- Ryan, 2008, Thalbitzer, 1945
- Ryan, 2008
- Søren Flensted
- Ryan, 2008
- Archive of Danish Council, Danish National Archives
- Ryan, 2008, www.cwgc.org