Description
North American B-25 Mitchell Navigator’s Astrodome and Mounting Frame
Item Overview
This World War II-era navigator’s astrodome and mounting frame was designed for the North American B-25 Mitchell medium bomber. It installed on the upper fuselage behind the cockpit, above the navigator’s station. The transparent dome provided a clear view of the sky for celestial navigation and other visual observations during flight.
Identification and Features
Identification is based on the assembly’s shape, mounting details, visible component numbers, and comparison with a documented B-25 astrodome frame. Reference assembly P/N 82-310855 has the same formed circular frame, paired forked brackets, and bracket fastener arrangement. The numbers marked on this example, 82-310840 and 82-310845, identify components within the assembly rather than confirming that the complete unit is marked 82-310855.
- Item type: Navigator’s astrodome and mounting-frame assembly
- Manufacturer’s aircraft application: North American B-25 Mitchell
- Visible component number: 82-310840
- Visible component number: 82-310845
- Closest documented complete-frame reference: P/N 82-310855
- Mounting location: Upper fuselage behind the cockpit
- Physical features: Formed circular frame, two forked brackets, bracket fasteners, and transparent dome
- North American’s 82-prefix drawing series originated with the B-25C program but could remain on parts used in later Mitchell production
Astrodome Function
The astrodome gave the navigator an overhead view of the sun, stars, and surrounding sky. During celestial navigation, an aircraft sextant could be used beneath the dome to measure the altitude of a celestial body. The navigator combined these observations with accurate time, navigation tables, and other flight information to establish or correct the aircraft’s position. The frame secured the dome to the fuselage opening and supported the surrounding installation; it was not itself a sextant, compass, bombsight, or radar component.
Documented End-Item Application
The documented end item is the North American B-25 Mitchell. Early B-25C and B-25D aircraft carried the navigator’s astrodome behind the cockpit, and surviving reference frame P/N 82-310855 matches this assembly’s construction. Because North American continued using earlier drawing numbers when parts remained applicable to later production, the 82-prefix markings identify the B-25C origin of the design but do not establish the exact model or serial number of the donor aircraft.
Astrodome and Part-Number History
Earlier Mitchell aircraft used a flatter overhead window arrangement, while the raised navigator’s astrodome appeared during B-25C production. North American Aviation organized many aircraft parts under project-based drawing-number prefixes. The 82-prefix series began with the B-25C, but unchanged or revised parts could retain those numbers when used on later aircraft. This explains why a B-25 component can carry an 82-series number without proving that it was removed from a B-25C.
B-25 Navigation Installation History
The navigator worked in the fuselage compartment directly behind the pilots on applicable B-25 configurations. Navigation methods included pilotage, dead reckoning, radio navigation, and celestial observations. The astrodome was especially valuable during long flights over oceans, deserts, or areas with few visible landmarks, where star or sun sights could help the crew check its calculated position and remain on course.
B-25 Mitchell Weapons-System Background
The B-25 Mitchell was a twin-engine medium bomber built by North American Aviation. It first flew on August 19, 1940, and 9,816 examples were completed by the end of World War II. The aircraft was produced in level-bomber, low-level attack, cannon-armed, reconnaissance, patrol, and training configurations. The famous April 1942 Doolittle Raid used earlier B-25B aircraft, which predated this B-25C-origin astrodome design.
History of Use
B-25s served in every major combat area of World War II and were operated by the United States and several Allied nations. Mitchell crews conducted medium-altitude bombing, low-level attacks, strafing, skip bombing, maritime patrol, and attacks against enemy shipping. B-25C, B-25D, and related configurations operated across North Africa, the Mediterranean, Europe, the Pacific, and the China-Burma-India Theater, making accurate navigation an important part of both combat and ferry missions.
Condition
The available assembly includes the astrodome and formed mounting frame shown in the inventory photographs. Visible component markings include 82-310840 and 82-310845. No exact donor aircraft, production date, or B-25 variant is established by those numbers alone. An aircraft sextant, navigation instruments, and the remaining fuselage installation are not part of this listing.
Ideal For
This original-style aircraft component is well suited to restoration work, museum interpretation, and collections devoted to World War II aviation and early airborne navigation.
- North American B-25 Mitchell restoration projects
- World War II bomber displays
- Aircraft celestial-navigation exhibits
- Warbird parts and equipment collections
- Military aviation museums and educational displays
- Research into North American Aviation components
Approx length 18", Approx width 15", Approx height 1.5", Approx weight 8lbs.
Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item’s general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.
Please visit our page about order lead times here: Order Lead Times.