When we think of spies in the sky, we think of satellites, U2 spy planes and unmanned drones.
Spies in the sky have a long history.
A man in a tower, on a rocky outcrop, in the crows nest of a ship. Anything to give an advantage over the man on the ground.
The modern era of men actually up in the sky started with balloons and Sam Cody with his kites.
During World War One, pilots would go up in a Vickers FB5 with a large plate camera, stick the camera over the side, take a picture, change the plate glass in a black bag, replace the glass, then take more pictures.
In the interwar years, the experience gained by the RAF in gathering intelligence from aerial photography was lost. The strides that were made were in the commercial sector.
At the start of WWII, the RAF was very ill prepared. They used low flying aircraft flying at low altitudes, wrong cameras, wrong lenses. These were suicide missions, aka dicing flights, dicing with death.
An Australian maverick Sydney Cotton was allowed to set up his own unit using high flying modified Spitfires, no armour, no weapons, to gain altitude and speed. Lone missions of 2-3 hours. They would fly at an altitude above interceptors but below where they would display a contrail.
Sydney Cotton upset too many of the top brass once too often and on returning from a mission was fired.
It was a flight over a Norwegian fjord that identified the Bismarck. Absence of torpedo nets indicated it was about to set sail. It came to be known as ‘the picture that sank a battleship’.
Auschwitz was captured by chance. It was picked up by the camera because it was photographing an IG Faben chemical plant. The picture shows the rows of huts, the pits where bodies are being burnt, the crematoria, a train at the station unloading the next batch of Jewish prisoners to be killed. As this was not a priority, the picture was filed, not to be uncovered until 1979 when the CIA was examining the archives for pictures of Poland.
One of the most famous photos of WWII is of the Dam Buster raid showing the breached dam and the flooded countryside below the dam.
Mosquitoes were used for reconnaissance as was the Lockheed F5 by American pilots though by choice they preferred the British planes. During heavy bomber raids, Avro Lancasters also took photos.
The cameras used were in special mounts to minimise blur.
Taking photos is only the beginning, these then have to be analysed.
Bletchley Park is well known and the contribution it made to the war effort with code breaking, less well known RAF Medmenham, a requisitioned house, Danesfield House near Medmenham, in Buckinghamshire.
Trying to make sense of the bigger picture is like putting together a jigsaw with pieces missing.
Archaeologists are very good at this. The entire archaeology department of Cambridge University moved to RAF Medmenham. Soon the house was not big enough and Missen huts filled up the grounds.
A very academic atmosphere, but also artists, painters, cartoonists. The to be head of the Royal Ballet was there, Sarah Churchill daughter of Winston, Dirk Bogarde. Those in the enclosed arena had entertainment, lectures.
A large number of women were at RAF Medmenham, many of who were officers heading up their own teams. The best known Constance Babbington-Smith, a journalist with The Aeroplane magazine.
RAF Medmenham identified the V bombers, V1 and V2. From the size of a V1 and knowing the fuel the Germans used, it was possible to work out the range. London appeared to be the target. Drawing an arc centred on London, many more site were found.
From the information gleaned from RAF Medmenham, repeat missions were flown over identified sites.
From the different types of railway wagons used by the Germans it was possible to see what cargo they were carrying.
It was possible to measure objects with a great deal of accuracy.
From the length of shadows, knowing too the time of day, time of year and latitude, it was possible to calculate the height of objects. A special machine an Altazimeter was designed to do this.
With overlapping photos and using a stereo magnifier viewer it was possible to create 3D images.
Information was fed in by French and Norwegian intelligence and others in Occupied Europe. Aircraft would then take a look.
RAF Medmenham would create 3D models.
For the Dambusters Raid, they created a 3D model that was lit as it would look on the night of the raid lit by moonlight.
For D-Day, 30,000 models were created.
At the end of the war Germans had jet interceptors.
Germany did not place much emphasis on photo-reconnaissance, even though at the beginning of the war they had better aircraft and better lenses. They had no central intelligence facility like RAF Medmenham. Information would be handled locally.
Loosely based on a talk given by Taylor Downing at the Guildford Institute during the Guildford Book Festival.
Taylor Downing is author of Spies in the Sky. Taylor Downing is a TV producer and has produced more than 200 TV documentaries.