In my career in aerospace I’ve been through value engineering, total quality management (TQM), quality (KoalaT) circles, Six Sigma, just in time (JIT), lean engineering and other major programs. Lean engineering became fairly ubiquitous in the aerospace industry in recent years.

I thought most of these programs were based on good fundamental, if obvious, principles. Some of these programs were quality initiatives and some were manufacturing improvement initiatives. But the programs were marketed for profit, and they didn’t always have positive or enduring effects on quality. Management accepted or embraced them because they promised reduced costs.

Lean was pushed much harder by aerospace management than the earlier programs were. In some companies, lean achieved the status of a cult religion. Individuals who embraced the program, or just wanted to please management, got on the “lean bandwagon.” Some who resisted being “assimilated” by the lean “organism” were reassigned, marginalized or even terminated. I saw a number of mediocre engineers become lean zealots to please management. Some of these were promoted into management. This caused serious problems in some cases.

Unfortunately, I also saw a few good engineers stop doing the engineering work they excelled at to pursue the lean “path” as they thought it would be better for their careers than doing good engineering work. I also saw good engineers spending their time arranging and color-coding their files and folders and labeling books and cleaning up (5S-ing). This was sad to watch.

I saw an R&D department implement “standard work” for research, which I thought was oxymoronic.

In one project I worked on, a major lean event was held to optimize the manufacturing flow for a new product line. Numerous engineers, managers and even executives participated in the event at a very high cost to the program. They took measurements and made diagrams and put tape on the floor to show where equipment needed to be to optimize manufacturing. Unfortunately this was premature, as it had not been verified that the manufacturing operations worked the way they needed to.

As a result, when the first parts were built, there were serious fit-up and assembly problems that needed to be solved before any real parts could be made. To fix the problem new equipment was needed and the manufacturing line would need to be rearranged. Focusing on streamlining the process before validating it was folly.

Too many managers, too few good engineers…

The event they should have held was a technical review by outside consultants to critique the process to make sure that the process would work and that the requirements would be met.

This is not a problem with the principles of lean. It’s a problem with the implementation of it and with managers who don’t understand what they are doing.

Lean sees QA as a no value-added function. According to lean, inspection should be minimized or eliminated. This is justified as long as the manufacturing process is well understood, everyone does their job the way they should, all the equipment works the way it should, etc. But this is rarely the situation, at least in aerospace. If a part is made that doesn’t meet engineering requirements will it be detected? Not if no one is looking.

A lot of such programs work best in the high rate manufacture of identical or similar parts. They don’t fit as well in low rate manufacturing of complex aerospace parts.

I think lean is near the end of its cycle of popularity, and some companies will continue with it, or with parts of it, and others will not. I expect in a few years someone will market a new program and management will embrace it, as they have the other programs in the past.

What do you think the effect of lean engineering has been on quality?