100 Years of the National Collection of Aerial Photography

This month, the earliest holdings of one of the world’s largest collections of aerial photography will reach their 100th anniversary. Celebrate this amazing milestone and look back at the history of the collection with the NCAP Operations Manager, Rachel Nordstrom

The National Collection of Aerial Photography (NCAP) is one of the largest collections of aerial imagery in existence and some of our oldest images date as far back as November 1924.

NCAP holds over 30 million high-definition analogue images from the last 100 years, documenting historic events and places throughout the world. The collection tells the history of photographic reconnaissance.

We hold rolls of large-format film, boxes of photographs and digital aerial images. These are held alongside the sortie plots that record the areas photographed all around the world. This enormous archive amounts to nearly 150,000 boxes of prints, photographic films and associated records.

History captured from above

The oldest photographs in the collection date back 100 years. They document British efforts to record and map the territory of Hong Kong. The photographs were taken using aircraft that operated from HMS Pegasus, a seaplane carrier.

These images offer a fascinating glimpse into the city's past, capturing its essence before it underwent significant urban expansion throughout the twentieth century.

The origins of the collection as a coherent archive are rooted in the Second World War. The Allied Central Interpretation Unit (ACIU), based at RAF (Royal Air Force) Medmenham, Buckinghamshire, amassed tens of millions of aerial photographs.

These were taken by pilots and aircrew in specially modified aircraft to monitor enemy military activity, plan missions and assess bombing damage. Over 1.5 million aerial photographs were even captured from the German Luftwaffe.

Pioneering 3D technology

Most of the aerial reconnaissance photography created by the Allies during the Second World War can be viewed in 3D.

When two overlapping images are viewed through a stereoscope, the images combine to produce a single three-dimensional image. This technique allowed Photographic Interpreters to examine geographical areas and objects in far greater detail to extract valuable intelligence.

Perhaps most famously, the Allies were able to identify German secret weapons and installations thanks to stereoscopic viewing.

From wartime intelligence to educational resource

Following the end of the Second World War, the peacetime potential of the images for teaching and research was immediately recognised. University academics – many of whom had been wartime Photographic Interpreters working at the ACIU – expressed an interest in the collection.

Ultimately this led to the transfer of 5.5 million photographs held at the ACIU to the University College of North Staffordshire (now Keele University ) in the early 1960s. This led to the establishment of the Keele Air Photo Library, which was later renamed The Aerial Reconnaissance Archives (TARA).

In 2008, TARA was transferred into the care of the Royal Commission on the Ancient and Historical Monuments of Scotland (RCAHMS). It joined the existing collection of imagery from the former archive of the Air Photographs Unit at the Scottish Office.

Following this, the merged archive was renamed The National Collection of Aerial Photography (NCAP).

Documenting change over time

The collection did not stop growing after the Second World War. Throughout the Cold War, photographic reconnaissance missions continued to inform UK foreign policy. This vital intelligence was central to many British and NATO military and humanitarian operations.

As images are declassified, the collection continues to grow. Photography from the Cold War represents a vital record of history and change and is available for the public to explore online via our Air Photo Finder.

But NCAP doesn’t just care for military images. In the collection, you can find images taken by commercial air survey companies, government bodies and scientific research units. This includes the 1.7 million images created for the Directorate of Overseas Surveys (DOS), which provide a comprehensive and unique photographic record of 55 countries throughout the Commonwealth.

Looking ahead by looking back

The National Collection of Aerial Photography continues to expand through a range of international partnerships. We’re working with the U.S. National Archives and Records Administration to make previously unexplored Second World War and Cold War aerial photography accessible online for the first time.

Many of us have relatives who were?involved in the Second World War, and even more of us can recognise the places captured from above in the aerial photography. It is truly fascinating to view the images taken during and after the global conflict. Our planet has changed over time and this archive shows you just how much.

Learn more about the history of NCAP and the collections work today by visiting our website.

You can also explore our collection of over 30 million aerial images from across the world and the past 100 years on our Air Photo Finder.