Overview
ISO 9667:2017 - Aircraft ground support equipment - Tow bars - specifies the dimensional and physical requirements for tow bar connections to tractors and aircraft. Applicable to new commercial transport-category aircraft tow bars designed or built after publication, the standard harmonizes tow bar attachments by aircraft mass category so a single tow bar head (with appropriate shear levels) can serve all compatible aircraft manufactured to ISO 8267.
Key Topics
- Scope and applicability
- Applies to new tow bar types for commercial transport-category aircraft.
- Interfaces referenced to ISO 8267-1 / ISO 8267-2 for mainline and regional aircraft.
- Aircraft connection requirements
- Tow bar heads must be compatible with the aircraft horizontal pin per ISO 8267.
- Grip requirement: device shall uniformly engage 96–98% of pin length.
- Anti-disengagement design and clearance envelopes for safe engagement/disengagement.
- Protective provisions
- Mandatory shock/overload protection (e.g., shear pins, energy-absorbing devices) to protect nose landing gear.
- Devices must alert the tow tractor operator when actuated and remain captive to avoid FOD.
- Shear pin requirements: non-standard diameters, shear at or below manufacturer force, tolerance (+0/−10%), and defined shear plane with hardened bushings.
- Tractor connection
- Tow bar eye and rotating tow bar eye dimensions specified; pintle or hook hitches are discouraged to limit load spikes.
- Tow bar performance and undercarriage
- Tow bar shall sustain at least 150% of protective device functioning point.
- Unladen stability and towability up to 25 km/h (15 mph).
- Wheeled undercarriage with height adjustment and CG limits for safe hookup.
- Markings, documentation and tests
- Indelible markings for allowable aircraft types and maximum towing force; vendor nameplate required.
- Tests and instrumentation to substantiate protective-device operation on request.
- Options
- Flyaway designs, separable heads, warning systems, cable provisions and retention lanyards.
Applications
ISO 9667:2017 is used by:
- Tow bar manufacturers and GSE designers for compliant product design.
- Airlines, ground handling companies, airports, and MROs for procurement and safe operations.
- Safety engineers and procurement teams ensuring compatibility with aircraft nose gear interfaces and preventing FOD or overloading.
- Regulatory and standards bodies referencing consistent requirements for aircraft towing equipment.
Related Standards
- ISO 8267-1 / ISO 8267-2 - aircraft tow bar attachment interface requirements (mainline and regional).
- EN 12312-7 - aircraft movement equipment (related GSE requirements).
- SAE ARP1915 - noted harmonization in the ISO 9667:2017 revision.
Keywords: ISO 9667:2017, tow bars, aircraft ground support equipment, tow bar attachments, shear pins, tow tractor, nose landing gear, ISO 8267.