CT03813-1 - Cobham Defense Mechanical Shackle Gravity Bomb Release Unit GBRU

CT03813-1 – Cobham Defense Mechanical Shackle Gravity Bomb Release Unit GBRU

Available now on the Airparts.aero Marketplace.

The Cobham Defense CT03813-1 is a flight-critical, OEM Mechanical Shackle Gravity Bomb Release Unit (GBRU) designed for precision stores carriage and reliable gravity-drop release operations across military transport, strike, and light-attack aircraft platforms. Positioned as a core electromechanical mechanism within the aircraft's Stores Management System (SMS) or exterior bomb rack pylon assembly, the CT03813-1 provides secure suspension and controlled release of external stores under extreme aerodynamic, thermal, and high-G flight regimes.

Engineered with a high-strength mechanical shackle mechanism, the CT03813-1 utilizes a low-friction over-center toggle latch that holds standard suspension lugs in a locked state until an electrical pulse or mechanical manual override command is executed. Upon command, the internal sear mechanism unlatches, allowing the store's weight and slipstream forces to rotate the shackles cleanly and jettison the ordnance or auxiliary payload without mechanical hang-ups. The unit is built to withstand high-amplitude acoustic noise, multi-axial engine vibrations, and severe atmospheric exposure typical of tactical flight profiles.

Through 30 years of hands-on experience troubleshooting flight control and stores release hardware, I can state authoritatively that armament suspension hardware leaves zero margin for error. A minor binding event or delayed release profile can disrupt weapon trajectory, destabilize airframe trim, or result in a dangerous store hang-up. Sourcing a genuine, factory-certified Cobham CT03813-1 unit through Airparts.aero ensures total mechanical integrity, precise release timing, and full compliance with military airworthiness standards.

Key Features

• Over-Center Toggle Latch Architecture: Utilizes a mechanical over-center sear mechanism that provides extreme holding force under high dynamic loads while requiring minimal input force to actuate the release sequence.

• Dual-Mode Actuation Interface: Features an integrated electrical solenoid for primary flight-deck-commanded release alongside a mechanical manual cable override for emergency jettison operations.

• High-Tensile Load-Bearing Hooks: Forged and precision-machined mechanical shackles engineered to support heavy external stores without experiencing localized yields or lug binding.

• Positive Anti-Rebound Guarding: Incorporates anti-rebound kinetic dampers and secondary locking latches that prevent accidental re-engagement of the hooks during store separation.

• Corrosion-Resistant Structural Enclosure: High-strength chassis treated with aerospace-grade passivation and dry-film lubricants to resist chemical attack from de-icing agents, hydraulic fluids, and salt-fog environments.

Technical Specifications

• Part Number: CT03813-1

• Component Type: Mechanical Shackle Gravity Bomb Release Unit (GBRU)

• OEM Manufacturer: Cobham Defense / Eaton Mission Systems

• CAGE Code: 05886 / 072E2 (Or as specified by OEM blueprint)

• Material Composition: High-strength 4340 VAR / 300M alloy steel load hooks, high-grade forged 7050-T7451 aluminum chassis (Specific material callouts subject to OEM blueprint verification)

• Finish / Surface Treatment: Cadmium plating per AMS2400 / Zinc-Nickel plating per AMS2417 with MIL-PRF-46010 dry-film lubricant

• Actuation Mechanism: 28 VDC Electrical Solenoid Primary / Mechanical Cable Manual Override

• Lug Spacing / Interface: Compatible with standard 14-inch NATO / MIL-STD-2088 suspension lug geometries (Confirm specific rack interface via CMM)

• Governing Specifications: MIL-STD-8591, MIL-STD-2088, MIL-S-8512

• Export Control Classification: ITAR Controlled Item / ECCN 9A610 (End-User Certificate required)

• Certification Status: Supplied with OEM Certificate of Conformance (CoC) or Authorized Military Airworthiness Release

Aircraft Compatibility

• Tactical & Strike Fighter Aircraft

• Light Attack & Reconnaissance Turboprops (e.g., A-29 Super Tucano, AT-6 Wolverine - where specified by weapons carriage IPC/Technical Orders)

• Military Maritime Patrol & Utility Platforms

• Note: The platform-specific Technical Order (T.O.), Weapons Delivery Manual, or Illustrated Parts Catalog (IPC) is the final, absolute authority for weapons rack component compatibility and structural effectivity.

Applications

• Gravity Ordnance Carriage & Release: Provides primary mechanical retention and release for unguided gravity bombs, practice stores, and dispensers.

• Emergency Payload Jettison: Executes rapid, mechanical release of external stores during flight emergencies or combat jettison scenarios.

• Target & Training Pod Suspension: Secures tow-target equipment and specialized reconnaissance/training pods to wing or fuselage hardpoints.

Why Choose CT03813-1?

Selecting the genuine OEM Cobham CT03813-1 GBRU is critical to ensuring operational safety and mission success. Non-certified or improperly overhauled release units frequently suffer from internal link wear, spring fatigue, or galling along the sear pivot pins. In flight, these defects can lead to high release-delay times, asymmetric store drops, or catastrophic store hang-ups that alter the aircraft's center of gravity. Sourcing an authentic CT03813-1 through Airparts.aero guarantees that internal tolerances, solenoid response profiles, and metallurgical treatments conform strictly to original defense manufacturing standards.

The operational physics of the CT03813-1 Mechanical Shackle Release Unit center on mechanical advantage, kinematics of over-center linkages, and tribological surface management. When an external store is loaded, the suspension lugs press against twin load hooks, rotating them into a latched orientation. This movement drives an internal toggle link slightly past its center axis (theta ^ circ) against a precision ground mechanical stop, creating an over-center lock. In this state, the downward gravitational and aerodynamic pull (F_store) exerted by the store actually increases the mechanical locking force on the primary sear. The release equation governing the required trigger force. To minimize the electrical power required from the 28 VDC solenoid and ensure rapid release response times under heavy dynamic shear strains (G = frac tau \ gamma), the internal components are coated with a molybdenum disulfide (MOS2) dry-film lubricant per MIL-PRF-46010. This prevents stick-slip behavior and galling under extreme normal forces (F_normal). Furthermore, the hooks are forged from 4340 VAR or 300M high-tensile steel heat-treated to an ultimate tensile strength exceeding 280 ksi, providing the high yield strength necessary to withstand multi-G maneuver spikes without permanent mechanical deformation.

Note: The CT03813-1 Gravity Bomb Release Unit is a military flight-critical weapons carriage and release component subject to International Traffic in Arms Regulations (ITAR) and strict defense airworthiness standards. Mechanical release shackles undergo severe cyclic loading during flight and must be meticulously inspected for wear, hook deformation, solenoid continuity, and freedom of motion prior to arming or flight operations. Installation, rigging, and functional arming checks must be conducted exclusively by certified armament technicians, weapons specialists, or authorized defense MRO facilities in strict compliance with the platform-specific Technical Order (T.O.), Weapons Maintenance Manual, or OEM directives.