Anyone got some T-cut?
Configuration Deviation List - basically the MEL for the aerodynamic surfaces - access hatches, winglets, that sort of thing. Many (me included) tend to say MEL when we really mean the CDL.
I did a flight test one time on a 747 that had been configured for a 'worst case' CDL dispatch for some other flight test conditions. The FMC struggled to do speed changes because the aircraft drag was so much higher than normal - it kept undershooting the speed target (which was part of my test conditions).
I did a flight test one time on a 747 that had been configured for a 'worst case' CDL dispatch for some other flight test conditions. The FMC struggled to do speed changes because the aircraft drag was so much higher than normal - it kept undershooting the speed target (which was part of my test conditions).
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As BEagle said there were a lot of warnings with aircraft like the VC10 where the pivot point is not the center point of the wings. The result is what is called 'swept wing growth' or 'delta growth'.
This is in Skybrary as a warning section:
See Skybrary Wing Tip Clearance Hazard
This is in Skybrary as a warning section:
All the aircraft involved in these occurrences were, like most modern large transport aircraft, swept wing types that are subject to a phenomenon known as ‘swept wing growth’ or ‘wing creep’. This occurs during a turn when the wing tip describes an arc greater than the normal wingspan due to the geometry of the aircraft and the arrangement of the landing gear. It is one of the reasons for the manufacturers' cautions usually found in the Flight Crew Training Manuals and can be well illustrated by a scale model of your particular aircraft. Although the effect is less noticeable at moderate curvature of turn, any turn results in some ‘swept wing growth’ that will erode the perceived wing tip clearance.
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There were some 'imaginative' solutions using sensors and drones a few posts back. But no one had the idea to use automated tugs. Hook it up, press a button and let a central computer do the clever stuff. So long as the software is not written by Tesla, it could work.
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Already happening Sid.
I'm not allowed to post links but if you do a Google search for: automated-aircraft-moving-at-heathrow ATI21 and click on the first link you will see exactly what you are proposing
I'm not allowed to post links but if you do a Google search for: automated-aircraft-moving-at-heathrow ATI21 and click on the first link you will see exactly what you are proposing
Just my two pence worth - all this talk of drones, automated tugs, sensors etc is all very well and is great “Blue Sky” thinking but from a airline CEO/CFOs point of view it is not about avoiding ground incidents, it is about making them affordable...and some of you are not thinking through the cost vs. Benefit analysis behind all of this.
It’s all about the cheapest short term option - if that is hiring and firing wingwalkers and paying the insurance premiums then you are not going to see companies spend large sums spent on technological solutions.
It’s all about the cheapest short term option - if that is hiring and firing wingwalkers and paying the insurance premiums then you are not going to see companies spend large sums spent on technological solutions.
Last edited by wiggy; 31st May 2018 at 07:44.
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Just my two pence worth - all this talk of drones, automated tugs, sensors etc is all very well and is great “Blue Sky” thinking but from a airline CEO/CFOs point of view it is not about avoiding ground incidents, it is about making them affordable...and some of you are not thinking through the cost vs. Benefit analysis behind all of this.
It’s all about the cheapest short term option - if that is hiring and firing wingwalkers and paying the insurance premiums then you are not going to see companies spend large sums spent on technological solutions.
It’s all about the cheapest short term option - if that is hiring and firing wingwalkers and paying the insurance premiums then you are not going to see companies spend large sums spent on technological solutions.
I am surprised there are no regulations on gate size and geometry vs aircraft wingspan, length and undercarriage geometry.
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Quote:
Originally Posted by wiggy
Just my two pence worth - all this talk of drones, automated tugs, sensors etc is all very well and is great “Blue Sky” thinking but from a airline CEO/CFOs point of view it is not about avoiding ground incidents, it is about making them affordable...and some of you are not thinking through the cost vs. Benefit analysis behind all of this.
It’s all about the cheapest short term option - if that is hiring and firing wingwalkers and paying the insurance premiums then you are not going to see companies spend large sums spent on technological solutions.
Originally Posted by wiggy
Just my two pence worth - all this talk of drones, automated tugs, sensors etc is all very well and is great “Blue Sky” thinking but from a airline CEO/CFOs point of view it is not about avoiding ground incidents, it is about making them affordable...and some of you are not thinking through the cost vs. Benefit analysis behind all of this.
It’s all about the cheapest short term option - if that is hiring and firing wingwalkers and paying the insurance premiums then you are not going to see companies spend large sums spent on technological solutions.
I am surprised there are no regulations on gate size and geometry vs aircraft wingspan, length and undercarriage geometry.
That combined with "acceptable risk" (aka insurance rates) likely means there will be no improvement seen in foreseeable future.
Regulators probably will not see this problem as a passenger safety risk, at least until someone manage to puncture a fuel tank.
Had a look at the site that you suggested. These tugs aren't automated as they still have a person walking beside them with a wireless controller. Big thing I noticed is that they are electric.
The device BA is using on some LHR pushbacks is a Mototok product ....and as you say they are not automated/automatic, they are controlled and driven by the accompanying handler.
Claimed advantages are manpower and environmental.
Last edited by wiggy; 1st Jun 2018 at 08:37.
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There is no reason that they could not be automated and know the precise path to take a particular airframe on each gate while scanning to ensure nothing has intruded on the required space for the aircraft path. Robotics is getting better all the time, whether robots or 'autonomous tugs' can cope with the mix of events on current ramps would need to be demonstrated, It is only a matter of time.
Short video
https://spectrum.ieee.org/robotics/r...-one-warehouse
Robotics is getting better all the time, whether robots or 'autonomous tugs' can cope with the mix of events on current ramps would need to be demonstrated, It is only a matter of time.
Out of interest if a robotic tug dinks a wall with a wing tip ( and it will happen) who will get the blame/picks up the tab????
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Out of interest if a robotic tug dinks a wall with a wing tip ( and it will happen) who will get the blame/picks up the tab????
Amazing that there are comments on here suggesting you go from flipping burgers one day to driving a tow/push back tractor the next. That's a bit like suggesting the next time an aeroplane crashes that the pilot was flying a drone one day and Captain of a wide body the next!
The GHA have a hierarchy on ramp jobs and driving a push back tug is only for experienced staff because oddly enough the GHA know it is a job that requires experience and competence.
The last GHA I was with had a 3D simulator that push back drivers had to master before being licensed to drive a push back tractor. This was configured with 4 different backgrounds of stands at the airport, including the 2 that were considered more challenging. On completion of their training they were licensed initially for narrow body aircraft, and only when assessed by the trainers as competent did they move on to additional training for wide body aircraft. Your airline will also have sent your auditors to check the training of your GHA, and push back training and licensing is always covered.
The drivers also have recurrent training every two years.
The other issue is that whilst the centreline is there as a guide, it isn't necessarily relevant to all aircraft types cleared to use the stand. Sometimes there will be a dotted line to follow for certain types that required a wider turning circle, but that is down to the airport operator to arrange.
The GHA have a hierarchy on ramp jobs and driving a push back tug is only for experienced staff because oddly enough the GHA know it is a job that requires experience and competence.
The last GHA I was with had a 3D simulator that push back drivers had to master before being licensed to drive a push back tractor. This was configured with 4 different backgrounds of stands at the airport, including the 2 that were considered more challenging. On completion of their training they were licensed initially for narrow body aircraft, and only when assessed by the trainers as competent did they move on to additional training for wide body aircraft. Your airline will also have sent your auditors to check the training of your GHA, and push back training and licensing is always covered.
The drivers also have recurrent training every two years.
The other issue is that whilst the centreline is there as a guide, it isn't necessarily relevant to all aircraft types cleared to use the stand. Sometimes there will be a dotted line to follow for certain types that required a wider turning circle, but that is down to the airport operator to arrange.
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I can see the attraction of a fully automated tug but I dont see that the technology is really there yet and aircraft stands have all kinds of vehicles driving across and equipment scattered around so it would be difficult to come up with an automated system that could account for all the variables for a possible collision.
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I can see the attraction of a fully automated tug but I dont see that the technology is really there yet and aircraft stands have all kinds of vehicles driving across and equipment scattered around so it would be difficult to come up with an automated system that could account for all the variables for a possible collision.
As for costs all the tugs would be around the same, probably not costing a lot more than a standard tug. If they were fully automated then you could reduce manpower and that will rapidly repay the capital cost of the tug. However, it will have knock on effects as the pushcrew are also often 'volunteered' to be ramp snow clearers so that pool of employees would need to be replaced. Robots would not be a one for one replacement.
Responsibility for software faults is always going to be an interesting issue,. Normally, the software is factory then site tested with the 'customer' representatives witnessing or even writing their own tests. When that acceptance test is signed off by the customer they have taken responsibility for the operation and potential errors of the software. There will be some residual support and maintenance from the supplier but the customer has taken responsibility for the operation and functioning of the software. (As a lot of you will have exercised my software in the past, I am rather glad of that
)
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I'm not convinced there would be a massive saving in personnel. You would still need someone to put the chocks in, plug in ground power, A/C etc. - if you dont use the tug crew then you need someone else. Also its difficult to count all the times that the tug crew avoid a collision or delay by moving some steps or a baggage trolley out of the way which if there were no crew the automated tug would simply have to stop (possibly blocking the taxiway) and wait for someone to be dispatched to remove whatever was causing the delay.
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Another advantage of an automated system is that the controlling computer can know the movement requirements for every aircraft. So that can be optimised much more efficiently in theory. And why not add other systems into it too - luggage and buses for example.