prizeframe From France, joined Nov 2012, 8 posts, RR: 0 Posted (2 years 9 months 2 weeks 4 days 19 hours ago) and read 2654 times:
I'm a student and right now I'm researching inefficient Maintenance, Repair, and Overhaul (MRO) operations that cause frustrating flight delays and safety hazards–not to mention wasted fuel and pollution.
Starlionblue From Greenland, joined Feb 2004, 17365 posts, RR: 66
Reply 1, posted (2 years 9 months 2 weeks 4 days 16 hours ago) and read 2654 times:
The article you cite is part of a thinly veiled campaign for SAP, a company with an obvious interest in having airlines its purchase data processing products.
Airliners don't stay in business by having constant costly delays and a host unexpected maintenance issues.
Quoting prizeframe (Thread starter): So.. Most airlines aren’t prepared to deal with the unexpected. This issues causes safety risks, customer dissatisfaction and planes standing on ground costing the airlines a lot of money.
Umm, no. Or at least nowhere near the degree implied in the article. Maintenance schedules ensure parts are replaced well before likely failure. Aircraft are typically checked daily and pre-flighted before every flight. Yes, the unexpected does occur, but those events are just a small percentage of what would happen if regular maintenance was not carried out.
"There are no stupid questions, but there are a lot of inquisitive idiots."
Most airlines are *extremely* well prepared to deal with the unexpected. People only see/hear about the failures without thinking much about how tiny a fraction of the successful operations the failures represent.
In the specific case of maintenance monitoring, this is the entire basis for Airman (Airbus), Aircraft Health Monitoring (Boeing), and whatever equivalent products the other OEM's have...these have been around for years.
Quoting prizeframe (Thread starter): This issues causes safety risks, customer dissatisfaction and planes standing on ground costing the airlines a lot of money.
To say that unexpected maintenance causes a safety risk is stretching the concept of safety risk pretty hard...it would be a safety risk if they didn't ground the airplane. The fact that they do shows you that they're prioritizing safety over schedule (as they should).
Because most aviation components are so reliable that the failures are essentially random events. Those few systems where you can do trend prediction to failure are already doing it (e.g. engine vibration monitors). Those few systems where they're not very reliable already have a huge amount of airline/vendor/OEM horsepower working them...the airlines don't need big data to tell them where those problems are.
The solution is improving the response time to unexpected failures: robust scheduling, systems that allow you to diagnose the actual fault faster, LRU's that are easier to replace (or getting rid of LRU's entirely), better spare parts supply chains so that the parts you need are available when you need them. And, surprise surprise, the OEM's and airlines have been working on these issues for decades and continue to do so.
prizeframe From France, joined Nov 2012, 8 posts, RR: 0
Reply 3, posted (2 years 9 months 2 weeks 4 days 14 hours ago) and read 2654 times:
Quoting Starlionblue (Reply 1): Umm, no. Or at least nowhere near the degree implied in the article. Maintenance schedules ensure parts are replaced well before likely failure. Aircraft are typically checked daily and pre-flighted before every flight. Yes, the unexpected does occur, but those events are just a small percentage of what would happen if regular maintenance was not carried out.
Thanks for the quick reply describing something closer to reality Starlionblue. Insightful for me..
New to the area and want to learn more, so am gonna read on around this. Thanks again.
Quoting tdscanuck (Reply 2): The solution is improving the response time to unexpected failures: robust scheduling, systems that allow you to diagnose the actual fault faster, LRU's that are easier to replace (or getting rid of LRU's entirely), better spare parts supply chains so that the parts you need are available when you need them. And, surprise surprise, the OEM's and airlines have been working on these issues for decades and continue to do so.
Sounds interesting, gonna dig a little deeper in improving the response time to unexpected failures. Thanks for the insight, helped me a lot.
I started a new thread to also change my direction a bit, based on a real world issue. If you can help me learn more about a painful problem in the life of technicians or just in the general maintanence area, please check it out. I called it "Flight technicians and others: Strange questions?"
That article is atrocious. It’s a thinly veiled sales campaign indicating that airlines aren’t prepared to analyze what happens related to maintenance. Maintenance accounts for about 7% of the operating budget at an airline. It depends on airline, but usually about 50% is scheduled (preventative) maintenance and the other 50% is unscheduled maintenance. Parts will always fail, so airlines try to get the most covered under scheduled maintenance since that is more manageable and cheaper to resolve.
First off, I think the premise is moving unscheduled maintenance into a scheduled maintenance program. Airlines have a scheduled maintenance program developed based on the OEMs guidance and requirements. The maintenance program is based on maintaining the safety and integrity of the airplanes and to prevent unscheduled maintenance. Maintenance programs have evolved dramatically. In the 1960s, United, FAA, NASA and Boeing developed MSG (Maintenance Steering Group) logic for how to conduct reliability centered maintenance. The premise is developing a maintenance program based on what fails and trying to predict it. Today there has been quite a bit of evolution. The industry is now doing MSG-3 analysis. Boeing, Airbus, Bombardier and Embraer routinely work together on creating requirements with the regulatory authorities are FAA, EASA and Transport Canada.
To put it simply, every failure mode is evaluated to the highest manageable level and then all failure causes are reviewed. It is determined based on impact of a failure (safety, operational or economic and hidden or evident) if a maintenance task should be created. The intervals are chosen based on predicatable reliability data and it is looked at the risk of failure and the opportunity of each task.
To get back to data, airlines have very robust logs of maintenance. The latest industry standard is SPEC 2000. The world’s leading airlines are all using that data format. This data is reviewed as a part of the reliability centered maintenance program which is required by the FAA, EASA and Transport Canada. Systematic problems are required to be identified and addressed. Airlines have some flexibility, for example some times fixes are optional such as incorporating Service Bulletins, but the airline must be aware.
And finally for the larger data picture, both Boeing and Airbus routinely review the maintenance of their entire fleets. The leading airlines all participate in data sharing. Airbus and Boeing do it differently. Airbus has various circles of support, while Boeing analyzes the data internally. The OEMs then optimize their maintenance program based on findings data from all around the world. This is used to adjust the intervals to catch the ideal number of events in scheduled maintenance without creating a maintenance program that is too much of a burden on operations. Airlines can then customize their own program. Both Boeing and Airbus will customize a maintenance program and there are third party companies that will do the same for smaller tier airlines.
Here are some quotes from that article that are completely are not correct in my opinion:
For example, a maintenance planner could download a defect notification from a plane as it occurs and have the maintenance crew and replacement parts ready by the time the plane pulls up to the gate. Even better, airlines could eventually use the data to predict and take action before the problem occurs.
This is already done! The airplanes have airplane health monitoring. The maintenance controller already gets this data and can work on getting the parts necessary to fix the airplane before it lands or have a mechanic ready to meet that airplane to issue a deferral. Airlines also already develop scheduled maintenance programs to predict the problems before they occur. The FAA requires each airline to have a reliability centered maintenance program.
Even more importantly, inefficient maintenance operations create safety hazards. The U.S. Office of Special Counsel recently chastised the Federal Aviation Administration for years of inattention to “lax airline maintenance.” Then there’s the wasted fuel and pollution caused by poor maintenance information.
Inefficient maintenance causes safety hazards!?! Who is that author to make such a claim. The safety record alone indicates that safety related events are extremely rare. Airlines are required to report significant safety problems as a part of the SDR (Service Difficulty Report must be filed to FAA within 48 hours) and the COSP (Continued Operational Safety Program) must be reported to the OEM within 1 week. All of this is tracked and evaluated.
Trouble is, that’s just the beginning of the data. Besides the plane itself, the other sources include the airline, aircraft manufacturers, external maintenance providers, regulators, and spare parts suppliers. Some of the data are structured (e.g., held within a database) but a significant subset—a pilot’s handwritten logbook entries, a technician’s notes—is unstructured
That is a problem of the past and is why SPEC 2000 was created.
If you have never designed an airplane part before, let the real designers do the work!
It really all depends on the department. Flight ops may need to move people. Routing may need to move another aircraft. Maintenance may need to move folks and resources. Maintenance planning may see a sizable work plan go into the trash because the aircraft went down right before some scheduled maintenance. Then routing needs to get the aircraft back into the system in the most efficient manner.
Quite simply, there is a cost to having a multi-million dollar asset sitting on the ground, incapable of performing its intended task. As far as non-monetary costs, I would have to say it's the goodwill of the customer. Strand a customer enough times or at some critical point, and you lose that customer.
Some can be. You get enough data on a fleet, you can predict fairly well when a component will fail or what component has failed within a system. Those are the parts you stock and that's the expertise you train to. Those are also the parts and systems that get attention in a maintenance plan.
But, most airlines already do this. And, the tools the manufacturers provide are fantastic and just getting better as time goes on.
We can look at aircraft, in the air, in real time and see what a monitored system is doing. Our aircraft will send us messages, independent of flight crew action, when the system sees a problem. We are able to give the maintenance crews a heads up and get parts moving to station or, in some cases, reroute the aircraft if the decision is made that it would be easier to get the aircraft back in service at a different, more capable station. This is a bit easier when you operate cargo vs. pax.
Fabo From Slovakia, joined Aug 2005, 1245 posts, RR: 1
Reply 6, posted (2 years 9 months 2 weeks 3 days 19 hours ago) and read 2654 times:
Quoting fr8mech (Reply 5): As far as non-monetary costs, I would have to say it's the goodwill of the customer. Strand a customer enough times or at some critical point, and you lose that customer.
It is worth adding, that even if said passenger would be willing to return, airline would still have to spend a lot of money on him. According to EU regulations, for example, MX delays are not considered "outside airline control" and as such, airline will have to provide accomodation, food, alternate routing, compensation, et cetera.
The light at the end of tunnel turn out to be a lighted sing saying NO EXIT