One can only imagine how much numeracy would improve in the UK if the metric muddle were finally resolved in favour of pure SI.

“This is an interesting article for one reason only; Boeing blames everybody else, but its management for the initial 6 months delay. Its by now replaced Vice President Bair asserts that some international suppliers contracted to design and manufacture sections for the Dreamliner are incapable of doing it. “They just could not do what we thought they could, said Bair. Some of the major airframe partners on the Dreamliner have performed so poorly that Boeing won’t probably use them on future programs, he said”.
What extraordinary statements to make! Did they not vet these companies properly before entrusting them with such demanding work? If not, who is to blame? The major metric companies, Alenia of Italy; Mitsubishi, Fuji and Kawasaki of Japan chosen to do this work are no backyard operators and know what they are doing.
Taking that into account one cannot help but think how much cumbersome old units contributed to this delay? One can well imagine metric designers and engineers struggling with units they have no feel for nor make sense to people used to simple mm.
If this is the case, Boeing blew the first billion dollars just to learn the obvious truth that metric users find medieval units cumbersome to work with. This is truly a high price to pay for obstinacy/arrogance.

You would not believe, but the majority of the structural threaded fasteners (bolts, screws, nuts) in the Airbus are in U.S customary dimensional units (a.k.a. “inches”).

Surprised?

(The Editor comments:

In 1949, Canada, the UK and the US adopted the inch-based Unified Thread Standard (UTS), which was intended to replace, among others, the BS Whitworth and the US Sellers threads. A driver of this change was the problem resulting from lack of interchangeability of equipment among the Allies in the WW2. ISO metric threads have now replaced Unified in most industries around the world, but it would appear that US dominance of the aerospace industry has ensured that Unified maintains a presence there.)

In fact you probably drive costs down. Fasteners on the A350 are likely to be the same size as those on the 787. So, suppliers can concentrate on one line instead of two.

Source: I work in the Aerospace industry as an engineer who has worked in both metric and imperial units.

As Qantas flies both Airbus and Boeing planes http://www.qantas.com.au/freight/dyn/capacity/capacity I don’t think that this problem is insuperable.

Also, though I am no technician, if Airbus can produce aircraft with metric components, then the “testing, documenting and certifying data and paperwork that come along with” the components must be at least partly in place.

I’m sure Boeing would prefer that, but that simply isn’t the case.

I would suggest that if Boeing wants to stick to US Customary, it should stick entirely to US suppliers. I worked in the automobile industry. The big reason we converted to metric in the 70′s was our own foreign operations and the worldwide supply base it opened to us.

Expecting people who don’t understand Customary units (and that includes EVERYONE but the US, because Imperial is different) to successfully manufacture in Customary, meet QC in Customary, etc, is pretty naive and probably frought with folly. Outsourcing and Customary just DON’T go together, not well, anyway.

It’s not a matter of swapping out the standard fastener with similar size metric fasteners (if they exists). Each standard fastener type and size has an enormous amount of testing, documenting and certifying data and paperwork that come along with them. Counting all the rivet, bolts, screws and mating part types that are used, the cost of converting over may even dwarf the US deficit!

Then go ask the airlines if they are willing to live with two sets of system (standard for the older airplanes and metric for the new airplanes) you may not be able to sell them a metric airplane ever.

The font example is actually quite interesting, because it historically reflected the size of the block on which the type was carved. It doesn’t reflect the actual character height of the type. Two fonts of different faces, but the same nominal ‘point size’ can be very different in height of actual characters, and even of spaced text.

The modern desktop publishing point of 1/72 of an inch was only fixed in the 1980s and is simply a rounding of the previous standard of 1/72.27 inches, to make it more amenable to computer software. (This comes from Adobe’s PostScript; earlier rendering software such as the TeX system use the older standard).

See http://en.wikipedia.org/wiki/Point_(typography).

However, I think this may be a unit so well entrenched in its field that it won’t be amenable to metrication. It’s rare that anyone actually wants to know how many lines of text of a given point size fit onto a sheet of paper in modern desktop publishing; changing the typeface will cause text to reflow in any case as the width of the characters, and the spacing between them, is different for each face (with rare examples where one font has been unnaturally forced into the metrics of another, e.g. Monotype Grotesque was distorted into Helvetica’s character sizes to produce Arial).

(1) US units are not “Imperial” in the common sense of Britain’s 19th century third empire (India and Africa). They instead derive from Britain’s 18th century second empire (North America and Caribbean). Although the length units are equivalent, the liquid units and dry volume units are often widely divergent from the Imperial units. Imperial units were standardized after the US became independent, and the US standardized its own units separately from Britain.

(2) No disloyalty involved. Mike is just being funny. The controlling clause is “except to the extent that such use is impractical,” which is a loophole a mile (or approximately 1.6 kilometers) wide. It’s the same principle that allows US states to declare a budget emergency every year and override various budgeting restrictions continually so that they’ve never been enforced. Go find an average American on the street, and 90% of the time, they can’t think metric except to the extent of a 2-liter bottle of cola. Canadians find this very amusing every time they visit.

(3) US dominance in aviation has led to delayed metrication. Flight levels are given in hundreds of feet to this day in most of the world, including in metric western Europe. (Not Russia, though. Thank God, or at least Marx, for the Soviet Union?) US insularity in defense spending has also delayed the impact of Airbus, while the auto industry’s troubles with Japanese and German competition sped up their metrication. There are other worldwide industries where US units are entrenched, such as publishing: 12-point font = 1/6 of an inch, even if you print stuff out on A paper sizes.