The SR-71 Blackbird's predecessor created "plasma stealth" by burning cesium-laced fuel

Skunk Works needed a way to hide the A-12's radar reflecting behind, so they dumped cesium into its fuel to create a radar-absorbing exhaust plume, write Joseph Trevithick and Tyler Rogoway or TheDrive.com.

At the Air Force Week New York City proclamation ceremony, an A-12 reconnaissance aircraft, the predecessor to the Air Force's SR-71, is on display on the USS Intrepid Sea, Air and Space Museum Aug. 24, 2010.
At the Air Force Week New York City proclamation ceremony, an A-12 reconnaissance aircraft, the predecessor to the Air Force's SR-71, is on display on the USS Intrepid Sea, Air and Space Museum Aug. 24, 2010.
U.S. Air Force photo/Lance Cheung

WASHINGTON - Lockheed's A-12 Oxcart spy plane, which the company developed for the Central Intelligence Agency, was a direct response to the growing vulnerability of its earlier U-2 Dragon Lady to hostile air defense networks. As such, the plane – the predecessor to the U.S. Air Force's iconic SR-71 Blackbird – was extremely high- and fast-flying, but also incorporated then-state-of-the-art features to reduce its radar cross-section. These included a combination of a stealthy overall shape and radar-evading structures, as well as the use of composites in its construction, and the incorporation of radar absorbing materials on its skin. A far less known, but still a key component of the Skunk Works plan to make the A-12 harder to spot on radar involved a cesium-laced fuel additive to dramatically reduce the radar signature of the plane's massive engine exhausts and afterburner plumes by creating an ionizing cloud behind the aircraft to help conceal its entire rear aspect from radar waves, write Joseph Trevithick and Tyler Rogoway or TheDrive.com. Continue reading original article

The Intelligent Aerospace take:

September 13, 2019-The technological leap aviation saw in the first 60 years of the 20th century still floors me decades later. From the Wright brothers' initial flight in 1903 through the Second World War was a steady progression of propeller plane powered technological advances. Aircraft could go further, higher, and faster as the years progressed. Twenty-five years after the Wright brothers' achievement at Kitty Hawk, British inventor and officer Frank Whittle developed the concept of jet propulsion, and Nazi Germany was the first country to develop a jet prototype, and eventually utilized its small supply of jet aircraft in its last ditch effort to defend its homeland from advancing allied forces from the east and west.

Advances in the post-war years were astronomical, and it's hard (for me, at least) to appreciate just how astronomical a jump it was for planes to jump from internal combustion engines and propellers to supersonic, stratospheric flight in aircraft capable of outrunning missiles in a few short years. Trevithick and Rogoway's in-depth look at the technology and development behind the A-12 Oxcart - the predecessor to the USAF's legendary SR-71 Blackbird - is an interesting look at early stealth technology that made leaps and bounds during the Cold War.

Related: What it takes to keep the B-2 bomber flying

Related: Boeing to build 17 P-8A surveillance and reconnaissance planes in $2.2 billion order

Related: U-2 Multi-spectral Sensor upgrade for U-2 aircraft to be provided by Goodrich

Jamie Whitney, Associate Editor
Intelligent Aerospace

More in Military