DTD189A-21SWG (1-KG-REEL)

DTD 189A Chromium-Nickel Corrosion-Resistant Steel Wire, Rivets & Split Pins

Overview

DTD 189A is a Ministry of Defence Aerospace Material Specification covering chromium-nickel corrosion-resistant steel wire, rivets and split pins. The specification applies to stainless steel wire suitable for locking wire applications, together with rivets and split pins manufactured from the same material. Although declared obsolete by the UK Ministry of Defence in 1999, the document remains a recognised technical reference for servicing legacy aerospace equipment where contractual agreement permits its continued use.

Key Technical Specs

• Specification: DTD 189A (Superseding DTD 189)
• Material: Chromium-nickel corrosion-resistant stainless steel
• Applications: Locking wire, rivets and split pins
• Manufacturing Process: Electric steelmaking process
• Supply Condition (Wire): Fully softened or fully softened and lightly drawn
• Softening Heat Treatment: 950°C-1150°C followed by rapid air cooling or quenching in oil or water
• Minimum Tensile Strength: 35 tonf/in�
• Bend Test Requirement: 180° bend without signs of failure
• Special Bend Test: 650°C heat treatment followed by copper sulphate corrosion test and 90° bend without failure
• Applicable to wire, rivets and split pins manufactured from compliant material

Approvals & Specifications

• Ministry of Defence DTD 189A Aerospace Material Specification
• Inspection and testing in accordance with British Standard 3S.100 (referenced clauses)
• Tensile testing in accordance with British Standard 4A.4
• Declared obsolete by the UK Ministry of Defence from 1 April 1999 for new approvals, while remaining available for legacy servicing applications

Typical Applications

• Aircraft locking wire
• Corrosion-resistant aerospace rivets
• Aircraft split pins
• Legacy aircraft manufacturing and repair
• Maintenance of older military and civil aircraft platforms
• Replacement of hardware manufactured to historic DTD specifications

Compatibility & Safety Notes

• Technical content remains valid for legacy servicing where agreed by purchaser and supplier
• Original MoD approvals associated with DTD specifications lapsed on 1 April 1999
• Current environmental and procurement regulations should be considered before specifying this material
• Wire should be free from harmful manufacturing defects before acceptance
• Material identification and inspection markings must be maintained throughout supply

Packaging & Procurement

• Wire supplied in coils or straight lengths with inspector identification tags
• Rivets and split pins supplied in bags or boxes with inspection markings
• Material batches identified by cast, diameter and heat treatment condition
• Legacy specification retained for servicing existing aerospace equipment

Why This Product is Chosen for AOG / MRO

• Provides corrosion-resistant locking wire and fastening materials for legacy aircraft
• High mechanical strength combined with excellent ductility for safety-critical applications
• Proven specification with long aerospace service history
• Suitable for maintenance where historic DTD compliance is specified
• Supports continued airworthiness of older aircraft fleets using original material standards

Practical Suggestions for Your Team (AOG Mindset)

• Confirm whether current aircraft documentation still permits DTD 189A material before procurement
• Verify modern equivalent material specifications where replacement is acceptable
• Ensure supplied material includes full traceability and chemical analysis documentation
• Inspect locking wire and fasteners for manufacturing defects before installation
• Retain inspection records for legacy aircraft maintenance documentation

Manufacturer / Aviation Spec Codes

• Specification: DTD 189A
• Issuing Authority: UK Ministry of Defence (Procurement Executive)
• Material Type: Chromium-nickel corrosion-resistant stainless steel
• Primary Applications: Locking wire, rivets and split pins
• Status: Obsolescent specification (from 1 April 1999) retained for servicing existing equipment