Overview
This is a specialized vintage mechanical slide-rule navigational computer used by U. S. military pilots and navigators to calculate dead reckoning, true airspeed, fuel consumption, and wind correction angles.
Identification
Photo reference
2 uploaded photos
Overview
This is a specialized vintage mechanical slide-rule navigational computer used by U. S. military pilots and navigators to calculate dead reckoning, true airspeed, fuel consumption, and wind correction angles.
Story
The CPU-26A/P is a specialized mechanical slide-rule navigational computer used extensively by U. S. military pilots and navigators during the Cold War era. Manufactured under military specification MIL-C-27216A by contractors like Felsenthal Instruments Co. and Aero Products Research, it was an essential tool for calculating dead reckoning, true airspeed, and wind correction before the advent of digital GPS systems.
Maker / Origin
Unattributed
Condition & Value
Based on the provided context, the item appears to be in typical vintage condition. The presence of the original protective case significantly aids value, while any smudged printing, bent aluminum, or missing center pivot screws would detract from it.
Full Research
Sold comps, value drivers, and venue guidance pulled from recent auction results.
The secondary market for vintage analog flight computers is stable but modest, driven by aviation enthusiasts, student pilots, and militaria collectors. These items were mass-produced for the military and civilian aviation sectors, meaning supply generally outstrips demand. Sales are most active on general marketplaces like eBay and specialized militaria sites, with condition and completeness dictating the final price.
▲ Presence of original printed protective case or sleeve
▲ Clear, legible anodized aluminum scales without heavy scratching
▲ Confirmed U. S. Military specification (MIL-C-27216A) markings
▼ Missing center pivot screw or warped aluminum wheels
▼ Heavy smudging or fading that renders the calculation scales illegible
▼ Absence of the original protective case
Best Venue
List on a broad marketplace like eBay or Etsy with clear, well-lit photos of both sides of the computer to demonstrate scale legibility. Price at $25 for a standard listing if the case is included, or bundle with other vintage aviation gear to increase the overall transaction value and offset shipping costs.
Upside Potential
If the item includes its original printed instruction manual in pristine condition alongside the case, the value could push slightly above the $35 high-end to appeal to completionist militaria collectors.