Nose Gear Towbarless Tow Vehicle Basic Test Requirements
The purpose of this specification is to provide airplane operators and tow vehicle manufacturers with:
a. General design and operating requirements pertinent to test and evaluation of towbarless tow vehicles. Specific design requirements are provided in ARP4852 and ARP4853.
b. Test and evaluation requirements. The results of these test evaluations will determine if the loads induced by the tow vehicle will exceed the design loads of the nose gear, or are within the aircraft manufacturer’s limits so that they do not affect the certified safe limit of the nose gear. The results of these test evaluations will also determine if a stability problem may occur during pushback and/or maintenance towing operations with the tested airplane/tow vehicle combination.
This document specifies general test requirements and a test evaluation procedure for towbarless tow vehicles (TLTV) intended for pushback and maintenance towing only. It is not meant for dispatch (operational) towing (see definitions in Section 3). Dispatch towing imposes more fatigue cycles on nose gears and structure due to additional passenger, cargo, and fuel loads, as well as more starts, stops and turns. Airframe manufacturers may require submittal of test results for evaluation or may provide information which allows TLTV manufacturers or airlines to self-test or evaluate the towbarless tow vehicles themselves. Refer to the airframe manufacturer's documentation for evaluation requirements and detailed testing procedures that may be different than contained in this specification.
TLTV manufacturers may elect to prepare and provide customers or regulatory agencies with a “Certificate of Compliance” or equivalent documentation as evidence that successful testing and evaluation of a specific tow vehicle/airplane type combination has been completed in accordance with this ARP and/or the applicable detailed airframe manufacturer’s documentation. This certification will allow usage of the vehicle on specifically designated airplane model types. The certificate should be established under an appropriate quality control program meeting the requirements of ISO 9000 Series or equivalent.
This specification requires that the TLTVs under consideration be maintained and operated in a serviceable condition. In addition, the vehicle to airplane interface protection system shall be calibrated periodically. This information is defined in ARP5284 and ARP5285.
Rationale: Towbarless towing has been practiced for over 20 years. During this period airframers as well as towbarless vehicle manufacturers have acquired many data and experience. In the light of this experience test complexity has been reduced and updated in this document while keeping the same level of requirements.