Flight Command Indicator ID-524/ARR-39A for SAGE System

The ID-524 Flight Command Indicator was a panel mounted component of the AN/ARR-39A Fire Control Data Link System, connecting to the ground-breaking system known as SAGE - Semi-Automated Ground Environment. The AN/ARR-39A system was installed in F-86D's Sabrejet Fighters along with an extensive electronics package in the late 1950's, becoming the F-86L Sabre Interceptor aircraft of the US Air Force. SAGE, an innovation developed by MIT, was the US's first air defense system (extensive history can be found here).  A cross-linked network of radar and communication, the system could vector interceptor aircraft to an inbound threat in real time. The SAGE system was later interfaced with versions of the F-89 Scorpion, F-94 Starfire, F-102 Delta Dart and F-106 Delta Dagger. However, we've only found evidence documenting this particular indicator as being used in the F-86L. This indicator, with a 1957 date stamp and a blue Confidential tag attached, displays altitude (COM ALT) and air speed (