BS ISO 9667:2016 pdf free

BS ISO 9667:2016 pdf free.Aircraft ground support equipment一Tow bars
The tow bar shall incorporate a device or devices, such as for example shear pins (typically two,respectively for push/ pull and torsion protection), to protect the aircraft from damage due to towing which shall
一relieve fore/aft and torsional towing forces applied to the aircraft nose gear through the tow bar which exceed the maximum force recommendations of the aircraft manufacturer by means of a shock absorbing device that is designed to function at values below tow bar design values,
一have an energy-absorbing device in order to limit loads induced in the landing gear that shall be designed to function at values beyond tow bar design values,
一simultaneously alert the tow tractor operator, audibly, visually or both, that a device has been actuated,
一be replaceable or repairable with a minimum of effort, and
一transfer overload to a retaining feature preventing separation and therefore loss of control of the aircraft from the towing vehicle. The retaining feature shall allow free rotation on ±90° about aircraft centreline at the retaining fastener. The retaining feature should be designed so that the towing forces do not exceed the aircraft type manufacturer’s maximum force recommendations.See Figure 2 example.
If shear pins are used as a protective device, they shall
一discourage hazardous replacement and encourage the exclusive use of manufacturer’s original parts and be clearly identified for their specific usage,
一shear at or below the nominal force specified by the aircraft manufacturer(s),
一have a functioning point within a relative tolerance of (+0/-10 %), and
一have a specific predetermined shear plane, whether provided with or without hardened bushings(see Figure 2).
The tow bar shall be equipped with a wheeled undercarriage to support it while being moved unladen and to serve as height adjustment device while attaching the end connections.
The undercarriage shall be extendable by use of a mechanical device, or a hand pump and hydraulic cylinder. It shall retract mechanically or by hydraulic pressure release.BS ISO 9667 pdf download.