DAS2138-4 - Textron Aviation OEM O-Ring Seal

DAS2138-4 – Textron Aviation OEM Hydraulic Packing O-Ring

Part Number: DAS2138-4

Manufacturer: Textron Aviation (Hawker Beechcraft / Meggitt)

Common Synonyms: Packing O-Ring, Hydraulic Seal, BDI-DAS2138-4

Overview Section

The DAS2138-4 is a high-performance OEM Hydraulic O-Ring primarily utilized within the landing gear and braking systems of the Hawker 800/900 series aircraft. Manufactured for Textron Aviation by specialists like Meggitt Aircraft Braking Systems, this seal is a critical component for maintaining the hydraulic integrity of wheels, brakes, and antiskid systems.

This part is specifically engineered to meet the stringent demands of high-pressure hydraulic cycles and extreme temperature shifts associated with landing gear retraction and extension. Unlike general-purpose O-rings, the DAS2138 series is built to military-grade standards to ensure that the braking system remains pressurized and responsive during the high-energy event of a landing roll.

Enhanced Technical Data

Advanced Engineering & Application

The DAS2138-4 is designed for High-Duty Cycle Environments. In the Hawker braking system, O-rings must survive "Antiskid Cycling," where hydraulic pressure is modulated rapidly to prevent wheel lockup.

Engineering Insight: Extrusion Resistance

The -4 dash size features a specific Modulus of Elasticity that prevents the O-ring from "extruding"—being forced into the clearance gap between the piston and the cylinder—under peak system pressures that can exceed 3,000 PSI. This is achieved through a precise blend of elastomers that resist "nibbling" at the edges of the gland, a common failure mode in lower-spec seals.

Aircraft Compatibility

The DAS2138-4 is a vital part for the Hawker business jet family and associated braking components:

• Hawker 800 Series: 800, 800A, 800B.

• Hawker 800XP / 850XP: Standard equipment for the main gear brake assemblies.

• Hawker 900XP: Integrated into the digital antiskid and braking modules.

• Meggitt/Dunlop Systems: Used across various regional and business jet brake components manufactured by Meggitt.

The Textron Aviation DAS2138-4 is the industry-standard choice for Hawker operators and MRO facilities maintaining wheel and brake assemblies. Engineering a safe landing starts with the smallest components; this OEM O-ring ensures that your hydraulic system maintains the pressure required for effective antiskid and braking performance. With a verified 84-month shelf life and EASA/FAA approval, the DAS2138-4 offers the reliability needed for high-utilization charter and corporate operations.5 Don't compromise on braking safety—choose genuine Textron OEM seals for your Hawker fleet.

Installation & Maintenance Addendum

1. Gland Preparation: Before installing the DAS2138-4, ensure the landing gear or brake gland is free of "pitting" or microscopic scoring. A damaged metal surface will tear the new O-ring during the first pressure cycle.

2. Lubrication: Use only clean MIL-PRF-5606 hydraulic fluid to lubricate the seal. Never install this O-ring "dry," as it can twist in the groove (spiral failure) during piston assembly.

3. Removal Technique: When removing old seals, use only plastic O-ring picks. Metal tools can scratch the sealing surface of the Hawker's expensive magnesium or aluminum brake housings.

Eligible For Following Aircraft:

• • Textron Aviation Hawker 700
• • Textron Aviation Hawker 800
• • Textron Aviation Hawker 800XP-850XP
• • Textron Aviation Hawker 900XP