Dash 8-200
Flight Crew Air Transport Pilot (ATP)
Training / Qualification; Troubleshooting; Situational Awareness
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
General Flight Cancelled / Delayed; General Maintenance Action
Equipment / Tooling; Human Factors; Procedure; Company Policy
After pushback and while the ground crew was disconnecting the tug; we were informed that the right nose wheel tire appeared flat. We decided to taxi back into the gate and have Maintenance look at the discrepancy. After deplaning we inspected the tire; finding no visible damage to the tire; however; it did appear to have deflated considerably. The First Officer stated that during the walk around; everything appeared normal. After Maintenance replaced the nose gear tires; they stated that there were marks on the right side tire consistent with the lift type tug 'claw' device that 'traps' the tires in place so the nose gear can be raised slightly onto a platform attached to the tug to facilitate pushback. Maintenance stated that this has been an issue in the past on at least one of our flights and several other air carrier's flights; where the ground personnel don't allow the aircraft to be pulled far enough forward onto the tug platform; or [don't] make sure the nose wheel is straight in-line with the tug before raising the 'claws'. This causes the claw to lift one or both nose tires into the air; (instead of sliding behind them; trapping them into place like they're supposed to); which can push the tire off of the rim causing loss of pressure. From speaking with Maintenance; it is believed that this is what happened in this instance. Better training for ramp crews; awareness of the hazards involved with these types of tugs and the effect they can have on our equipment if everything isn't aligned correctly. Perhaps exploring a different tug type application; perhaps a normal tow-bar-tug in place of the lift-type-tug; would certainly act to eliminate these types of issues.
Reporter stated Maintenance informed them this type of tire damage or loss of tire air pressure has happened before using a similar type of tug on other DHC-8's and also on Saab 340 aircraft. Reporter noted the aircraft tow tugs are Lektro electric tugs. Reporter also stated the information noted in the original report may not have been correct regarding the reference to 'the claws' causing damage to the tires; but rather damage may be caused by nose tires being pulled too far forward onto the platform.Reporter stated low tire pressure is not always easy to determine; but can create a lot of problems if a nose tire blows due to low pressure. Reporter air carrier has not decided yet whether to go back to using the old style solid tow bar type connection for moving their aircraft.
Pilot reports nose gear tires on aircraft have been found damaged; deflated or with low tire pressures that Maintenance believes is caused by improper use of towbarless type tugs by ramp personnel.