Posted by: conservativecritic | January 30, 2013

BOEING 787 – AN INVITATION TO THE FUTURE….OR TO A DISASTER?


The Boeing Company has a strong and lengthy record of engineering marvels…spanning decades of air travel, aerospace and military accomplishments.  Virtually all of these advances were based on careful and incremental changes to similar, earlier technologies or proven aircraft.  The movement to the next “level” was always measured and carefully analyzed for risk and unexpected operating conditions.  This type of careful engineering has kept Boeing at the forefront of aviation for the past generation.

Chevy Volt crash...and an exploding lithium-ion battery days or weeks later!

Chevy Volt crash…and an exploding lithium-ion battery days or weeks later!

The European Airbus changed that conservative perspective when the Airbus became a prime competitor.  All of a sudden, the Airbus competition and the “green” environmental movement motivated Boeing management to take a huge gamble….that of an advanced design that moved hardware functions into software, converted mechanical control systems to electrical and at the same time sought a new level of fuel efficiency by the  use of lightweight structural systems.

Any one of these items is a challenge in of itself.  However, not having many of these new technologies in house, Boeing was forced to outsource a majority of the aircraft’s key subsystems, thus taking important quality control functions out of the hands of the prime contractor and dropping them on piecemeal equipment  houses around the world who had little or no knowledge of how their systems would function in the entirety of this new, advanced airframe.

The current Boeing 787 problem lies in its electrical power system and associated controls.  Lithium ion batteries and cells have become the fair haired child of electric cars(except for exploding VOLT autos) and a variety of lap-top and pocket held devices(wait until a lithium ion battery in a laptop explodes on the lap of a pregnant woman or destroys the genitals of someone using the laptop).

With the transition to more electrical controls, the need for the rapid charging and “cold start” capacity of the Lithium ion cells should have been a red flag to Boeing since lithium ion batteries have a very limited range of safe operating conditions as shown below.
lithium_window as Smart Object-1

As you can see, Boeing engineers have painted themselves into a corner….or perhaps better stated, into a very small box!  There’s not much wiggle room in this situation.  Japan has already secretly replaced a small truckload of these failed batteries in 787 aircraft…without alerting the aviation regulators.

It is important to remember that Japanese officials and industrial representatives are not always forthcoming about problems that occur within the confines of Japan – witness the lack of truthfulness on the part of the Japanese after the Fukashima nuclear accident.  So, this 787 battery replacement issue by the Japanese may well be far beyond what we are now hearing.  That explains why US aviation investigators are questioning Boeing regarding the battery replacements by the Japanese airlines.

It’s easy to see from the chart above that lack of control of charging, discharging, temperature and cell voltage quickly puts one into the red zone.  While the battery itself may be stable within the confines shown above, the extreme dynamic conditions of external demands for power and recharging conditions as well as ambient temperature and cell voltage status require careful monitoring.

The FAA and other agencies have already begun speaking with companies who provided the monitoring systems for these lithium ion batteries….I assume they already have this type of chart in front of them.

So, is the Boeing 787 safe to fly?  As an engineer with a wall full of electrical engineering degrees, I say there is not a chance at this time…until Boeing figures out how to provide the requisite amount of electrical power to enable its advanced control and maneuvering and operating systems…while staying within the small box shown above.  This is a major engineering oversight that hopefully will not cause loss of life due to battery failure or fires while in flight.

Unfortunately, the design movement from hardware to software and greater dependency on electrical power may not leave much room for redesign using conventional batteries….or alternatively, not much sunshine for the lithium ion technology until a better safety control “coccoon” is built around the power system.

Furthermore, the backlash has already started.

The US Postal Service (USPS) has announced that it’ll refuse to ship any gear containing lithium ion batteries overseas. The postal service believes combusting lithium ion power packs have caused two fatal cargo plane crashes since 2006 — hence the ban, which takes effect from May 16th. Anyone wishing to ship the latest tech to those living or serving overseas will have to use another shipping company — although the ban might be relaxed in 2013, once intensive safety testing has been carried out.

What do you think?

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