On 29 November 1940 a German reconnaissance aircraft crossed Wiltshire from the Avon gorge to the Hampshire border with two cameras running. Its 44 Wiltshire photographs survive in the US National Archives. Joined in order, the long-lens frames make a strip some 40 km long, and the film below flies it again: Avoncliff, Trowbridge, Bratton, Salisbury Plain, Stonehenge, Amesbury, Redlynch. For where these prints come from and every other Luftwaffe frame of the county, see The Luftwaffe's Wiltshire and its map.
Sortie GB 1209
NARA files the prints as box GX 10484. Each print carries its own record. A titling strip gives the German sortie number, the camera and the date: GB 1209 L 29 11 40. A data panel gives the film number, the exposure number and the focal length of the lens. In the bottom corners are a clock and a level bubble.
Two cameras ran together. The L camera had a lens of 505.13 mm and took the close views, about 4.6 km square on the ground (exposures 109–135, film 1537). The S camera had a lens of 200.56 mm and took views about 11 km square (exposures 84–103, film 955), mounted the other way round. The two scales differ by 2.5, the ratio of the two lenses, so both cameras were looking down from the same height.
The backs show the paper and the custody. Each is printed on Agfa-Lupex paper, annotated in German pencil, typed "GX 10484" and stamped "Copied by Photo Rec. & Serv's Div, AAG, Hq. USAF". Exposure 131 of the L run and exposures 91 and 96 of the S run are not in the NARA set. The whole sortie runs to 254 frames, beginning off the Devon coast; the Wiltshire stretch is this post's subject.
A picture every fifteen seconds
The clock in the corner of each print shows the time of exposure. The centre of the dial is covered by a pencilled "29.11. L", but the ends of the hands are clear. The hour hand stands just short of two throughout. The minute hand reads 34.3 on exposure 109 and 40.7 on exposure 135: 26 exposures in about 6½ minutes, roughly one every 15 seconds. Each reading is good to about ±0.2 minute.
The S camera's clock runs 2.2–2.5 minutes ahead of the L camera's over the same ground, so the two clocks were not set together. Neither the time zone nor morning or afternoon is written on the prints; the film gives the clock readings and no more.
Joining the frames
Each L frame overlaps the one before by about 55%, and each is about 2.1 km further on. The frames were matched on several thousand common points per pair, each against its neighbour and the one beyond, and fitted together in a single adjustment that holds the scale steady from end to end. Most joins fit to within 2–4 m on the ground; over the Avon gorge, where the valley sides shift between viewpoints, to about 8 m. Each part of the strip comes from one photograph only, with a narrow seam between frames, so that hedges and trees are never doubled.
The scale comes from two known distances. On the long-lens strip, Bratton Castle to Stonehenge (23.8 km) gives 1.32 m of ground per scanned pixel. On S 102, Old Sarum to Figsbury Ring (5.2 km) gives 3.22 m per pixel.
The frames lean about 15° off the line of flight, the drift of an aircraft crabbing into a crosswind. At exposures 129 and 130, over Amesbury, they swing round by 12° and then 16°: the aircraft turned south over the Avon towards Clarendon and Redlynch.
What the interpreters wrote
The pencil notes on the backs name each frame by its map sheet and by the most prominent landmark in it. In every case read, that landmark is a prehistoric monument:
Back of print L 116: "Bratton Cas. b. Bratton sö Bristol / Bl. 32." Agfa-Lupex paper. NARA RG 373, GX 10484.
| Pencil note | Meaning | |
|---|---|---|
| L 116 | Bratton Cas. b. Bratton sö Bristol Bl. 32 | Bratton Castle, near Bratton, south-east of Bristol, map sheet 32 |
| L 126 | Stonehenge written and struck out | |
| L 128 | Tumuli b. | Barrows near Stonehenge, struck out |
| S 097 | Yarnbury Castle nw Salisbury Bl. 33 | Yarnbury hillfort |
| S 102 | Old Sarum u. Figsbury Rings bei Salisbury Bl. 33 | Old Sarum and Figsbury Ring |
"Bl. 32" and "Bl. 33" are the same map-sheet numbers as the "Engl. Bl." references on the Luftwaffe target dossiers. None of the notes read names an airfield or a camp, though military sites on the Plain lie in the same frames.
Stonehenge
Stonehenge on L 127, 29 November 1940, shown as flown (top of picture to the south-east). The old A344 runs beside the stones. Luftwaffe, NARA RG 373, GX 10484.
Stonehenge falls on only one long-lens frame, L 127, close to its edge, and on S 098. The bank and ditch, the sarsen circle, the A344 beside the stones and the custodian's buildings are all clear. On the frames either side, 126 and 128, the interpreter wrote "Stonehenge" and then struck it out. The stones are not in either picture.
The aircraft
No record yet found names the aircraft, its unit or its crew. NARA's item records give none, and NCAP's Luftwaffe collection is uncatalogued at sortie level. The prints narrow it down. Lenses of 50 cm and 20 cm are the standard pair for German long-range reconnaissance, usually the Rb 50/30 and Rb 20/30 on 30 × 30 cm film. With that film, the ground each frame covers puts the aircraft about 7,800 m above the ground. Spacing and clock together give a ground speed near 500 km/h. Both fit a Ju 88 reconnaissance aircraft with a tailwind, or possibly a Do 215. Aufklärungsgruppe 123, Luftflotte 3's reconnaissance group in the west, was flying Ju 88s over southern England that month and lost two of them, at Parkstone on 14 November and at Coates on 24 November. All of this is an estimate; the film says so.
Notes on the film
The landscape film runs at about four times real speed and is turned so that the aircraft flies left to right. Each frame is captioned with its exposure number, NARA's nearest place name and its clock reading. It pauses on Bratton Castle and Stonehenge, which are shown from the original full-resolution scans. The missing exposure 131 is a short black gap. The short version opens on Stonehenge and then flies from Avoncliff to Bratton. The music is original.
A fascinating then and now comparison companion video:
Sources
- National Archives and Records Administration. German Flown Aerial Photographs, 1939–1945. RG 373, series NAID 306065; file units GX 10484 SG. catalog.archives.gov/id/306065
- National Archives and Records Administration. Target Dossiers Pertaining to the British Isles, 1938–1945. RG 242, series NAID 3371016. catalog.archives.gov/id/3371016
- National Collection of Aerial Photography. German Air Force (Luftwaffe), GB 551 NCAP/4. ncap.as.atlas-sys.com
- Luftwaffedata Wiki. Aufkl. Gr. 123 1940. luftwaffedata.co.uk
- Luftwaffedata Wiki. Aufklärungsgruppe Ob.d.L. luftwaffedata.co.uk
- Daw, T. 2026. The Luftwaffe's Wiltshire. sarsen.org; map at wiltshire-luftwaffe.netlify.app
All photographs: Luftwaffe, 29 November 1940; US National Archives, RG 373, GX 10484, listed as Use: Unrestricted. Frame matching, measurements and film: T. Daw. Methods and scripts: github.com/TimDaw37/wessex-films.
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