A day in the life

SYDNEY - I’m Down Under at the moment, where I’ve had a successful media briefing discussing our 20-year market forecast for the region. I’m also heading to New Zealand later in the week.

Meantime, I wanted to touch base on some progress back home for the Dreamliner. It’s called “fatigue testing,” but engineers on the 787 program are definitely not feeling any fatigue of their own as they begin this critical phase of testing.

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The 787 structural airframe in the test rig.

The fatigue testing on the 787 structural airframe in Everett is intended to demonstrate the ability of the Dreamliner to maintain its structural integrity over its lifetime.

If you’ve never seen fatigue testing before, the photos here give you a good idea of what it’s all about.

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Fatigue testing exposes the structural airframe to the typical operating loads that a fleet of 787s would experience while in service.

A full-scale airframe is placed in a test rig. There we simulate more than three times the design service objective for the 787.

This is also an opportunity to check the structural inspection and maintenance procedures as well as the durability of the airframe structure.

We’ve put together a short video piece explaining what fatigue testing is all about. You can check it out below:

The loading is applied in a series of segments representing a flight - from pushback at the departure gate to arrival at the destination gate.

We call this a ground-air-ground (GAG) cycle, and yes, it includes both ground and flight loads.

We run five different types of cycles representing differences in duration and severity of flights in the fleet.

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So, this “day in the life” process now under way is one more series of tests for the Dreamliner.

It will all ultimately help us ensure the 787 will provide the lifetime of safe and reliable service our customers and their passengers will expect for many years to come.

Comments (7)

Laurern Countryman (Everett):

Does the fatigue testing include occasional simulations of encounters with severe turbulence?

Windshears?

Hard landings - several different types, including severely crabbed?

Norman (Long Beach, California, United States):

I would imagine that the fatigue testing for this airplane will exceed all prior testing for all earlier aircraft but the plane is made to outlast the all aluminum airframes by quite a lot of cycles.

Thomas Horstmann, Jr. (Portland, Oregon):

While I understand the need for fatique testing, I don't see how you can possibly condense a 30 year service life test into a few days or weeks, as it wouldn't realistically duplicate the stresses the aircraft goes through on a daily basis.

That said, I hope no surprises pop up as the program needs no further delays, not sure how much more the airlines will take before bailing.

Joe (Tempe, AZ):

@Thomas,

Someone correct me if I am wrong but this test will last 3 years and actually test 3 life cycles. I am not sure exactly how they condense time but I would imagine that a 14hr flight won't take that long in the rig.

Also, it is noteworthy that the most stress occurs per cycle not per flight hour so they may simulate numerous 1hr flights instead of fewer 14hr flights.

Thomas Horstmann, Jr. (Portland, Oregon):

I was wrong, it isn't a couple week test, as I assumed. In three years of 24 x 7 testing, it likely at least provides Boeing with some idea of the Dreamliners strengths and weaknesses in terms of fatigue. So disregard my last message, please.

BA Investor (New York, N.Y.):

I believe that the fatigue testing will go on for three years in order to validate the full life of the 787.

However, it will only take 3 months to qualify for certification. The rest is to establish longevity.

It would have been helpful for this process to be better described. However, I understand that if you mentioned a three years test, the press would claim it as a three year delay!

Good luck. This shows that 787 is getting closer to final certification. Three months from now is still in 2010

Marco Canesi (Pisa (Italy)):

Very interesting!
I would like to know how the inertial load of the payload is simulated.

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