Published in the Daily Bugle, September 29, 2023
The EAR has a number of conventions, one being the use of quotes for defined terms. Double quotes are for global definitions used in multiple locations throughout the CCL, gathered in EAR Part 772. Single quotes are for local definitions for a particular ECCN, and found in its Note or Technical Note. As a reminder, a Note clarifies what is included in the control, or what the entry doesn’t control – it should not expand the scope of control. A Technical Note should clarify the meaning of technical parameters, provide test methods, or when necessary, provide the local definition.
Good practice is for terms used only once to be included in the control text itself, but that often makes for an ugly mess. One solution is a local definition that stands in for a technical paragraph (or six). Coming up with local definitions is an art, and a dark one at that. ECCN 1B117 unhelpfully defines a ‘mixing/kneading shaft’ by declaring it is most definitely not a deagglomerator[1]. The EAR is filled with these surrogates; some are straightforward[2], like industry standard ‘stress rupture life’; some are giggle worthy, like ‘splat quenching;’ others corrupt common terms like ‘carpet rolls[3];’ and a few are just clearly made up, like ‘hole shape ratio,’ which came into existence in the Wassenaar in 2011, and the EAR the following July in 9E003.c.
Gas turbine engine combustors and turbines operate at ferocious temperatures, stressing the limits of the best metallurgy. Having your turbine parts melt is, as one wise man puts it, a good way to interrupt the in-flight movie. One mitigation is to blow air from inside the part through many teeny-weeny[4] surface holes. This carries away some heat, but also forms a thin air film on the part’s surface, protecting it from the incredible temperatures. This cooling air is a debit to fuel efficiency – it’s drawn from the compressor, which reduces thrust, and it cools the exhaust stream that took fuel to heat up (which reduces thrust).
Drilling the holes is difficult – they are very small[5] to use the cooling air efficiently and the materials are both very hard and fragile. You can easily mess up the part (and weaken the material) by drilling it wrong. It’s difficult to make a small hole through a thick piece of metal (relative to the hole size), especially at the steep angles that best produce surface films. 9E003.c controls the technology for making deep teeny-weeny holes at funny angles in engine parts.
In 2010 the text of 9.E.3.c (Wassenaar) / 9E003.c (EAR) was recognized as having issues[6]. The intent was to only control process technology, but vague wording caused many companies (and some governments) to incorrectly interpret it as controlling any data, such as the hole location. It was specific to only a few listed drilling methods, which meant new methods weren’t controlled. It didn’t specify which parts were being drilled, so applied equally to tough-to-make turbine blades and easy-to-make oil jets. The biggest issue was that it relied on hole diameter. That might have been fine in the 1980’s, but by the ‘naughts, holes in turbine parts included ovals, rectangles, and slots, to name a few.
Pray tell, what is the diameter of a rectangle? I’ll wait.
Thus, in addition to clarifying the entry as a process control and to which parts it did and didn’t apply, it needed a topographically agnostic way to specify teeny-weeny deep holes, as diameter was, well, shape-ist[7].
When clarifying a control, attention is paid to prevent expanding the scope of the control, otherwise known as a Rollback[8]. Expanding the control on technology uncontrolled for a long time is a bad thing[9] as you may suddenly need licenses for stuff that was NLR before, you may have to reclassify stuff, and spend resources analyzing existing classifications to prove they’re still correct. Therefore, we needed to describe teeny-weeny deep holes that resulted in the same scope of control as if the holes were cylindrical. After a lot of algebra and geometry, ‘hole shape ratio’ defined the area to depth ratio, independent of shape.[10] A thus a local definition was born.
9E003.c is the “technology” “required” for manufacturing cooling holes. The Wassenaar is a consensus body, and there was an inordinate amount debate about the right verb, as the biggest concern was a hole is the absence of material, so what best describes the creation of nothing from something? I can attest that everyone in the room was sober, as this smacks of the type of discussion that results from use (no quotes) of materials controlled in regulations other than the EAR. Faced with Yet Another Local Definition to describe the manufacture of surfaces within structures that connect to the inner and outer faces, the philosophers gave up and the pragmatists agreed on manufacturing holes.
if you have comments other oddities to discuss, or J&C questions, the offer stands – please reach out to me at ArtOfJC@arinovis.com.
[1] A deagglomerator is used in applications that involve deagglomeration. That clears things up nicely!
[2] Straightforward to a small group of experts, but still….
[3] A type of rocket propellant, not wall-to-wall. DO NOT confuse them at Home Depot.
[4] Note the lack of quotes, single or double.
[5] About the size of ten strands of hair, or a billionth the surface area of an Olympic swimming pool, to use two of the most common useless scales.
[6] Here’s where we introduce Air Quotes.
[7] Apologies for using a culturally-insensitive term, but we’re all professionals here.
[8] Used without Walmart’s permission.
[9] Unless, apparently, it’s to China.
[10] Tucked neatly into a Technical Note, as it should be.