This P-38 recently discovered, named “Echo,” was first detected in 2011. Arctic Hot Point Solutions returned to the site earlier this year with radar-equipped drones to aid in the search for more planes buried in the ice. The group used a heat probe to penetrate the ice in an attempt to touch the suspected airplane. The probe was retrieved coated in 5606 hydraulic fluid, widely used in aircraft. "We weren't anticipating that," explained Jim Salazar, a co-founder of Arctic Hot Point Solutions, told Popular Mechanics. "We pulled the probe back up, and lo and behold it had all that hydraulic fuel all over it."