&gt;&gt; they would leave big airplane-shaped objects on the tarmac to create cold spots for Soviets&#x27; spy satellites to photograph in infrared, corresponding to planes that didn&#x27;t exist.<p>You&#x27;re referring to project OXCART which preceded the Blackbird program. The documentary you&#x27;re referring to was called &quot;Area 51 Declassified&quot; which was on National Geographic channel:<p><a href="https:&#x2F;&#x2F;youtu.be&#x2F;fE8xqTO6hXk" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;fE8xqTO6hXk</a><p>It&#x27;s a fascinating documentary