mike's web log

The Comet had its turbojet engines buried within its wings. Piston-era practices started all big-jet designers off on the wrong foot, Boeing included. Propeller airliners had their engines in line with the wing and actually faired into it, so by default that was where people thought jets should have their engines. This unquestioned assumption -- a good example of the tyranny of a reigning paradigm -- led de Havilland's talented designers to place the Comet's four engines inside its wings.

Going this route has a few problems. First, it tends to make the jet airplane's engines difficult to access and maintain. Second and more important, it can endanger the entire airplane if something goes wrong with one of the engines. [Like explosions or fire.]

Boeing was the first company to correctly assess jet-age safety concerns and come up with the optimal solution: strut mounting. Boeing designers attached the turbine engines to their struts by means of fuse pins. In the event of an out-of-balance condition, the fuse pins would shear and the damaged engine would fall away, sparing the airplane.

The secret to success in any business is to properly define and meet customer requirements. It's all the more important in commercial aviation, because jets are so enormously costly to develop that mistakes carry heavy penalties.

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By far the biggest lesson I learned from the 737 was never to take an initial design configuration as a given. It's human nature to do just that and go charging ahead to work within an existing framework. However, that doesn't necessarily lead to great airplanes.

Engineers love to dive right in an analyze the hell out of reams of data. Very often, though, they can't see the forest for the trees because they haven't done the simple work up front to be sure that they're starting down the right path. The time for detailed work with massed computing power is after the basic concept has been properly defined.

The 737 taught me to step back at the outset of any program and take a clear, simple look at the basic physical problems that need to be addressed. The more brain power you apply up front, the greater the likelihood that you'll find the design path that solves your challenges and meets your customers' requirements.

By all rights, I should have felt weighted down. But I didn't. It was a good program and it fit my skills and personality. It's in my nature to assess issues and tackle problems as they arise, trusting that solutions will be found down the line to what I can't solve right away.

Our program pioneered the winning Boeing practice of inviting airline technical experts inside to help us develop our new airplanes. The 777 program took this concept to unprecedented heights. Pilots, cabin crews, maintenance technicians, and other end users lived with Boeing and participated on our 777 design-build teams to ensure that this great airplane is well thought out.

Safety is a broad and often abstract term. You don't design safety into an airplane; instead you design an airplane to have excellent airworthiness characteristics so that a pilot can handle it in good conditions and bad, including those unforeseeable occasions when damage is sustained, or the airplane must operate in severe atmospheric conditions, or when highly adverse conditions prevail during takeoff or landing. This in turn dictates a robust structure and engines that are reliable and powerful enough so that major events won't put the airplane into jeopardy. The airplane must be able to absorb punishment, and after it does, its pilot must be able to bring it in for a safe landing.

It seems essential to me that a project leader not fixate on one design parameter to the exclusion or detriment of others. Airplane design is the ultimate exercise in compromise. If you increase the fuel load, for example, you need a stronger, roomier structure to house it, so airplane weight and drag go up. You also need more powerful engines to lift it all, which means higher fuel consumption. The design team's job is therefore to define the optimal balance between these elements that yields the best results. The exception is safety, which is never subject to compromise.

Our morale was already high because we were getting the job done in the face of adversity. Then along came the campaign. My troops began griping about this inept campaign, which suggested to them that our senior management didn't understand or value what they were doing. The campaign reflected two insulting assumptions, one offensive and the other patronizing. The offensive part was the idea that we were all underperforming and needed to be motivated to achieve full productivity. The patronizing part was the apparent belief that cartoons were a way to communicate with engineers.

Then as now, my guiding belief is that you're not living up to the faith placed in you if you don't play things the way you see them. When you're in a position of responsibility, you need to do what's right. In the aerospace arena, if you don't have the courage to face up to difficult situations -- and that includes making sure that unwelcome truths are heard and acted on -- then you have no business being a chief engineer.