Begging For Lean Thinking
I don’t plan this stuff – it just happens, but this seems to be airline lean week. Any doubt about how badly the airlines need lean thinking has to be cleared up by this article from the Wall Street Journal about the airlines.
“Airlines began aggressively padding schedules in 2008 and 2009 so that even late flights technically arrive on time.” Scheduling a flight to take 2 hours and 15 minutes even though you know it will only take two hours sounds a whole lot like building two weeks of lead time into a manufacturing production schedule to increase the likelihood of shipping on time even though it really only takes a day to make something.
Time and inventory are just two sides of the same coin – pouring more inventory into the factory to compensate for problems just adds to the overhead expense, degrades quality and makes the underlying problems nigh unto impossible to solve. Seems as if extending flight times is exactly the same thing – with exactly the same results:
“You can do all sorts of things to make up for poor performance,” said Robert Isom, chief operating officer at US Airways, referring to padded schedules. “But you sacrifice efficiency, the passenger experience, the employee experience and profits.”
Lean folks know well the water and rocks analogy in manufacturing:
Inventory is the water in the stream, while the rocks are all of the problems creating excess costs, poor quality and missed deliveries. Old school thinking was to make sure there was always enough water to keep things flowing without having the rocks disrupt flow. MRP, in fact, was created specifically to be a tool to make sure there was always enough water to make problems appear to be invisible.
Lean theory is that kanban should effectively continuously drop the water level until another rock is exposed, making is easier to identify and solve the problem, then drop the water level again until another rock is exposed. This is the essence – the meat – of continuous improvement. Don’t lengthen lead times – keep shortening them.
Seems as though the airlines have their own water and rocks:
Instead of artificially lengthening flight times – increasing the amount of flights in process – to make the impact of all of the reasons flights are late invisible, the airlines should have been pursuing the lean continuous improvement approach. Shorten the scheduled time until something bites their on time performance – then kaizen that problem – fix the process – make that rock go away for good – then shorten flight times again until they get bit by the next biggest driver of missed on time flights.
In fact, burying problems with inventory happens everywhere …
… patients are scheduled in such a manner as to make sure there are always far more patients in the clinic than doctors to treat them – drive up the medical work in process levels to compensate for all of the reasons things don’t happen on time.
… schedule kids to be in school for seven hours in order to give them four hours of instruction to compensate for all of the wasted time in the education process.
The result is always the same – excess cost that does not create a lick of value for customers – delays and inability to deliver – lousy quality.
And the solution is always the same – shorten times – solve the problem – reduce the cost – improve the quality.
Category: Articles
Bill Waddell (Bill Waddell's Profile)
As a consultant Bill has worked with manufacturers of all sizes throughout the United States, Canada and Mexico, as well as in Europe, Asia, New Zealand and Australia. As an author, Bill has written Simple Excellence and Rebirth of American Industry, as well as others, has published numerous articles, and is the most widely read manufacturing blogger on the Internet. As a speaker Bill has addressed professional, academic and military groups on five continents, and has spoken and taught in virtually every leading manufacturing forum in the United States. Bill is a global supply chain expert, one of the original Lean Accounting 'thought leaders', has served as a technical chairman for various manufacturing quality forums, and is regarded as a leading expert in lean manufacturing.Subscribe
If you enjoyed this article, subscribe to receive more just like it.
Well stated but flawed for the simple reason that you have assumed the outcome desired by airlines is more efficient, well run operations. The reason schedules were padded is because the published metric that they believe matters is on-time performance. They believe on-time performance drives preference and if they can improve on-time performance by padding the schedule that is much less expensive than actually solving the root cause problems.
While I do not work for an airline, I suspect they would also argue that most of the root cause problems of delays are outside their control, so padding the schedule is the right answer anyway.
While they continue to have these beliefs, while losing money, Southwest Airlines recognizes that planes on the ground do not make them any money, so they work to minimize ground time. And, they make money … consisently. That being said, they have added an average of about 10 minutes to their ground time planning as well.