A few weeks ago, Des Barker sent me the following interesting pictures showing the impact of a civilian plane with a tractor. The text of the email explained that on Jan 1, 2009, “after pushback from the gate in LA, the pilot throttled up to taxi before the tractor and bar were disconnected”.
The images let me think how dangerous, some normal airport activities, can be, so I asked to my friend Giovanni Maduli, who works at Rome Fiumicino airport, to explain how the push back of an aircraft takes place. This is what he explained:
“Even if the push back is performed using different kind of tractors, the main rules remain the same. Using both the tractor that “catches” the nose wheel gear or the one with the push back towbar, the first thing to do is to insert the “NOSE GEAR LOCKPIN”. This pin acts on the valve that inhibits pressure to the nose gear. Then the steering height must be checked so as to avoid the tractor from impacting and damaging the landing gear doors. Some aircraft have a “red stripe on nosewheel doors” marking.
During the push, the towing tractor can’t exceed the maximum steer radius and speeds; should the safety pin break, there would be a loss of directional control. The ramp operator and the crew in the cockpit must be in radio contact: via headseat, by means of the aircraft’s interphone system; or by means of walkie-talkies. Any emergency or problem must be immediately notified on the radio. Two operators use the towbar tractors model Fresia, with the help of a ramp technician: one operator seats on the back of the tractor (on the opposite side of the driver) to help this latter whose visibility is obstructed by the aircraft when it is angled by 45° to be aligned with the taxiway’s centerline and can’t check for any obstacle. With the other kind of tractor, the “Kalmar”, the push back is easier since the nose gear is directly connected to the tractor and not by means of a tow bar. This kind of tractor requires a single operator (the driver). The “Fresia” model towbar tractor requires much more attention. The push back can’t be performed if there are more than 50% of the engines at IDLE. A series of safety bolts, that must be checked before the hook up, prevent the bar from stressing the nose gear structure. The bolts are calibrated to sustain an amount of stress that does not damage the gear. When the bolts break, a quick reaction of the ramp operator is required to prevent any injury or damage to the aircraft.
When the push back is completed and the aircraft is on the taxiway’s centerline, the pilot radios the “Parking Brakes On” to the ramp operator, who gives the driver the clearance to disengage the tractor. Radio contact between the ramp operator and the cockpit must be kept until the tractor is outside of the aircraft cleared taxi route”.
As a Tug driver for over 30 years and at various Airports (Heathrow being the (bussiest) i CAN SAY THAT i HAVE HAD TO PERFORM THE PUSHBACK MANY DIFFERENT WAYS FOR DIFFERENT HANDLERS AND CARRIERS.
This being most common.
I am connected via push bar to aircraft (having first put the bypass pin into nosegear) , vissually check with captain that his breaks are set and if so indicate I am removing chocs.
I get back in tug, start her up.
Dispatcher performs walkround checking no collision damage whilst loading and that all doors and hatches are shut (most tug drivers are quallified to do this also)
Dispatcher informs captain that all is locked and we are ready for pushback….
Captain replies breaks off, commence pushback.
Dispatcher indicates to me(tug driver) of the direction she wants the nose to point at end of pushback, she taps her nose and points in the direction ( Iam trained in radio communications so I listen to the directions from ground as dont trust the dispatchers to get it right!
she then indicates that breaks are off, she does this by first holding an clenched fist up in front of tug, she then unclenches fist and waves me forward with a sweeping motion of the arm.
Pushback begins taking up small slack so as not to jerk aircraft or to break sheerpin, manual gear is selected and the speed is yours within reason ( I new of one tug driver who pushed back so fast that the captains used to shout brace brace brace if they saw he was the pushback driver lol). you pick up the centre line (tricky on a rainy night ) and end up with the main gear either side of centre line and nose gear bang on it.
indicate with a clenched fist to dispatcher that you have airbrakes on, she disconnects tow bar fron tug and then aircraft and removes bypass pin, this gives the steering back from tug driver to pilot.
At Luton tug stays in front of aircraft unyill dispacther is ready to walk to the stand, bar is connected to rear of tug and tug leaves the taxi way. dispacter shows bypass pin to pilot (long red tape hangs from it) so he knows he has control, engines were started during pushback.
safe journey
Hi, very interesting, Please send you e-mail i have to send picture and comments regarding safety pins.
Tks W.Besti
Walter, my email address is cencio4(at)gmail.com Ciao David
In the end i would like to know, if use of not certified safety pins, is forbidden or is allowed.
If not why, what could happen if the pin come out because has not the 2 little balls that can retain accidental exit. It seems that often in some airports, safety pins and red strap are home made and nobody take care about.
Any appropriate answer is really appreciate.
Bye all and very best regards
Dear Walter,
The use of un-approved nose landing gear by pass pins are not allowed and contradict any airlines push back policy or procedure.
Some handling companies in Rome use these home made versions as they lack quality control within the department and want to save money.
If one of these pins falls out on a push back considerable damage would occur plus a cancelled flight whilst waiting for spares and this would mount up to tens of thousands of Euro just for the price of a $20 pin.
Thanks Mr Robert , appreciate Yr replay and explanations, infact You made best score, this should be also usefull for Mr Cenciotti, so can give in future appropriate answer if some others will ask.
Mr Robert, please if You could qualify urself , it will, really complete the SAFETY PINS query.
Very best regards
WB