Description
20mm XM27 Powered Cupola Traverse-Mechanism Mounting Adapter Plate, P/N 11644011, FSN 1005-131-6269
Item Overview
This U.S. Army Adapter Plate, Mounting was made for the traverse mechanism of the XM27 powered 20mm gun-mount cupola. The curved, horseshoe-shaped plate formed a mounting or interface point above the main traverse-mechanism gearbox. This listing is for one military-surplus adapter plate only; the cupola, motor, gearbox, gun, vehicle, and other parts are not included.
Identification and Features
The Army parts list identifies this component by its complete nomenclature, part number, stock number, and exact location within the XM27 cupola traverse assembly.
- Official nomenclature: Adapter Plate, Mounting
- Part number: 11644011
- Federal Stock Number: 1005-131-6269
- Later NSN format: 1005-00-131-6269
- Quantity per assembly: One
- Application: XM27 powered cupola traverse mechanism
- Assembly group: Group 3004—Traverse Mechanism Assembly with Kemp Motor and Tubing
- Manual reference: TM 9-1005-307-24P
- Illustration reference: Figure 21, Item 9
- Usable-on code: A—XM27 Power Cupola
Function and Installation
The adapter plate was installed within the hydraulic traverse-drive assembly of the XM27 powered cupola. In the Army illustration, it sits above the main traverse-mechanism gearbox and provides a mounting or interface surface within the installation. The parts manual does not give a more detailed explanation of its individual mechanical function.
Cupola and Vehicle Application
Usable-on code A limits this plate to the XM27 powered cupola. It is not listed for the powered or manually operated M26 .50-caliber cupolas covered by the same manual. The XM27 was associated with the M114A1E1 armored command and reconnaissance carrier, which was later standardized as the M114A2. This cupola supported the 20mm M139 automatic gun.
Historical Background
The M114 was a small tracked command and reconnaissance vehicle developed for the U.S. Army during the Cold War. The vehicle family served during the Vietnam era and went through several weapon and cupola changes. The M114A1E1 introduced the XM27 powered cupola and 20mm M139 gun, giving the vehicle greater firepower than earlier .50-caliber configurations. When this improved model was standardized as the M114A2, its powered traverse system helped the gunner aim the cupola-mounted weapon.
Contract and Package Information
The package label identifies Contract DAAF03-70-C-0052 and carries a 3/71 date marking, indicating March 1971 packaging. It also bears “Type II” and Perishability Code 0. Government contract records state that Bauer Ordnance Company received this contract for 1,013 new H modification kits and spare parts for a gun-control system installed on the M114 vehicle.
Condition
This is a military-surplus mounting component and may show scratches, finish wear, discoloration, oxidation, storage residue, or other signs of age and handling. Packaging, labels, finish, and minor details may vary. Please check the pictures for the general condition of the item.
Ideal For
This uncommon XM27 cupola component is well suited for collections, restorations, and exhibits covering U.S. armored reconnaissance vehicles and automatic weapon mounts.
- M114A1E1 and M114A2 vehicle displays
- XM27 powered cupola restoration projects
- 20mm M139 gun-system collections
- Vietnam-era armored-vehicle exhibits
- Military museums and educational displays
- U.S. Army gun-mount research
Approx length 9", Approx width 6", Approx height 1", Approx weight 1.7lbs.
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.
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