Editing Operation Bertram (section)

=== Real and dummy ''matériel'' ===

[[File:IWM-HU-59572 Dummy tank frame over Jeep 1942.jpg|thumb|A mobile dummy: frame of a dummy tank over a truck chassis at the Middle East School of Camouflage near Cairo, photo by Captain Gerald Leet, 1942|alt=photograph of a wheeled chassis fitted with the frame of a dummy tank]]

Petrol cans were stacked along the sides of existing revetted trenches near El Alamein railway station. It was found by experiment that when they were hidden in the shadows in that way, they were invisible from the air and so 2,000 tons of petrol were thus stored. Over 100,000 four-gallon petrol tins{{efn|An [[Gasoline#Density|imperial gallon of petrol]] weighs about 7 pounds. A British [[long ton]] is 2,240 pounds. 2,000 tons would be 640,000 gallons or 160,000 four-gallon cans, not counting the weight of containers}} were stacked in the 100 stone-faced slit trenches.{{sfn|Barkas|Barkas|1952|p=198}}

Food was stacked in piles of boxes, and draped with camouflage nets to resemble trucks: a large box-shaped pile for the truck's body, and smaller piles for the truck's cab and engine. That meant that attractive materials including sugar and cigarettes were dispersed around the desert instead of being in readily-guarded camps. The most desirable items were therefore put in the "trucks" in the middle of the areas and hidden in the middle of each stack, and army command accepted the risk of theft.{{sfn|Barkas|Barkas|1952|pp=198–200}}

While the real supplies in the north were carefully hidden, matching dummy supplies had to be created in the south. In the area named Brian after camouflage officer Brian Robb, over 700 dummy stacks, representing food, petrol, ammunition and other supplies, were constructed.<ref name="Barkas 1952 p206">{{harvnb|Barkas|Barkas|1952|p=206}}</ref>

Static dummy tanks and guns were made mainly of local materials including calico and palm-frond hurdles.<ref name=IWM>{{harvnb|Imperial War Museum|2012}}</ref><ref name="Stroud 2012 p200">{{harvnb|Stroud|2012|p=200}}</ref> Some dummy tanks were mobile, consisting of light frames placed over [[jeep]]s.<ref name=Lucas123/> A total of 500 dummy tanks and 150 dummy guns were constructed.<ref name=Forbes165/>

One night shortly before the battle, a powerful dust storm destroyed many of the dummy vehicles. Ayrton worked throughout that night and all the following day to restore the "film set" to an appearance of reality. The Axis command did not notice the breakdown of the illusion. The Royal Air Force had established air superiority by 18 October and completely excluded German reconnaissance aircraft from the Bertram area from then until battle commenced.{{sfn|Richardson|1985|p=117}}