THINK FOR YOURSELF, SCHMUCK

...I guess I know what my next @nostalgebraist-autoresponder project is now, huh

In Chapter 115 of my book Foucault’s Pendulum the character called Casaubon, on the night of the twenty-third to the twenty-fourth of June 1984, after attending an occultist ceremony at the Conservatoire des Arts et Métiers in Paris, walks, as if possessed, along the entire length of the rue Saint-Martin, crosses the rue aux Ours, passes the Centre Beaubourg, and arrives at Saint-Merry Church. Afterward he continues along various streets, all of them named, until he gets to the place des Vosges. In order to write this chapter I walked the same route on several different nights, carrying a tape recorder, taking notes on what I could see and the impressions I had.

Indeed, since I have a computer program which can show me what the sky looks like at any time in any year, at whatever longitude or latitude, I even went so far as to find out if there had been a moon that night, and what position it occupied in the sky at various times. I did this not because I wanted to emulate Emile Zola’s realism, but because I like to have the scene I’m writing about in front of me while I narrate; it makes me more familiar with what’s happening and helps me get inside the characters.

After publishing the novel, I received a letter from a man who had evidently gone to the Bibliothéque Nationale to read all the newspapers from June 24, 1984. He had discovered that on the corner of the rue Réaumur (which I hadn’t actually named but which does cross the rue Saint-Martin at a certain point), after midnight, more or less at the time Casaubon passed by, there had been a fire—and a big fire at that, if the papers had talked about it. The reader asked me how Casaubon had managed not to see it.

It has a little hook on the back, so you can hang it off the edge of the pot, and it doesn't get your stove messy or your ladle contaminated with stovetop germs.

It has a pointy front that gets right into the bottom corner of the pot so you can scrape out the last bits of salsa or jam.

It's got pouring spouts on either side, so left or right handed people can easily use it.

If you fill it right to the top, it holds exactly enough to fill a half-pint jar with 1/4" head space, the correct amount of head space for most water bath recipes.

It's pretty! It's red and white! Look at this pretty red scoop with its pretty white handle!

The person or people who designed this object did so with deep knowledge and understanding of the process of canning food. They made it beautiful and functional. This and its matching funnel are probably literally the best $25 I've ever spent on any hobby.

But I'm really just overwhelmed about how much thought went into this simple object.

(previous post in this series)

My shop in Advanced Midbody - Carbon Wing (AMCW) at Large Aircraft Manufacturer (LAM) is at the very end of the composite fabrication building. Hundreds of people carefully lay up a hundred foot long slab of carbon fiber, cure it, paint it, and then we totally fuck it up with out of spec holes, scrapes, primer damage, etc. The people who write up our many defects are from the Quality Assurance (QA) department.

Every single screw and rivet on a LAM aircraft can be traced back to the mechanic who installed it. Back when even everything was done in pen and pencil, it was joked that the paper used to produce an aircraft outweighed the plane itself. Now that everything is computer-based, of course, the amount of paperwork is free to grow without limit.

(Haunting the factory is endless media coverage of an emergency exit door plug popping out of an Advanced Smallbody - Upengine (ASU) plane during a routine flight a few months ago. Unlike that airframe's notorious problems with MCAS, this was a straightforward paperwork screwup by a line worker: the bolts were supposed to be tightened, and they weren't.

As a result the higher ups have visited hideous tribulations on non-salaried workers. Endless webinars, structured trainings. Here at the Widebody plant we have received a steady flow of refugees from the Narrowbody factory, hair-raising tales of receiving one hundred percent supervision from the moment they clock in to the second they clock out from FAA inspectors who can recommend actual jail time for any lapse in judgement.)

A single hydraulic bracket Installation Plan (IP) is around four brackets. The team leads generally assign two bracket IPs per mechanic, since each bracket set is something like a foot apart, and while working on the plane is bad enough it's much worse to have another mechanic in your lap.

Let me list the order of operations:

One: Find where you're supposed to install these brackets. This is harder than you might think.

Firstly, it's a hundred foot long plank of carbon fiber composite, with longitudinal stringers bonded to it to add stiffness. The stringers are pilot drilled in the trim and drill center, a truly Brobdingnagian CNC mill that trims off the composite flash at the edges and locates and drills part holes for us. But there's a lot of holes, so you must carefully find your set.

A minor difficulty is that the engineering drawings are laid out with the leading edge pointing up, while the wing panels in our cells hang from the trailing edge. Not so bad, you just rotate the paper 180 when orienteering, then rotate it back up to read the printed labels.

A major difficulty is that the drawings are from the perspective from the outside of the panel. But we work on the inside of the wing (obviously, that's where all the parts are installed) so we also flip the drawings and squint through the back of the paper, to make things line up.

Large Aircraft Manufacturer has a market cap of US$110 billion, and we're walking around the wing jig with sheets of paper rotated 180 and flipped turnways trying to find where to put brackets.

Oh well, we're paid by the hour.

Two: Match drill the aluminum brackets to the carbon fiber composite stringer. I can devote an entire post to the subtleties of drilling carbon fiber, but I can already tell that this post is going to be a miserable slog, so I will merrily skip over this step.

Three: Vacuum up all the carbon dust and aluminum swarf created during this process. This step is not optional, as your team lead will remind you, his screaming mouth clouding your safety glasses with spittle at a distance of four inches. LAM is very serious about FOD. Every jet airliner is a wet wing design-- each interstitial space is filled with Jet A. There is no fuel bladder or liner-- the fuel washes right over plane structure and wing hardware. Any dirt we leave behind will merrily float into the fuel and be sucked right into the engines, where it can cause millions in damage. No place for metal shavings!

If you are nervous about flying, avoid considering that all the hydraulic lines and engine control cables dip into a lake of a kerosene on their way from the flight deck to the important machines they command. Especially do not consider that we're paid about as much per hour as a brand new McDonalds fry cook to install flight-critical aviation components.

Four: Neatly lay out your brackets on your cart, fight for a position at a Shared Production Workstation (SPW) (of which we have a total of four (4) for a crew of thirty (30) mechanics) and mark your IP for QA inspection as Ready To Apply Seal.

Four: Twiddle your thumbs. We have three QA people for thirty mechanics. This is not enough QA people, as I will make enormously clear in the following steps.

Five: Continue waiting. Remember, you must not do anything until a QA person shows up and checks the box. Skipping a QA step is a “process failure” and a disciplinary offense. From the outside, you can observe the numerous QA whistleblowers and say “golly, why would a mechanic ever cut a corner and ignore QA?” Well,

Six: QA shows up. Theoretically, they could choose to grab the mahrmax you prepared for them and gauge every single hole you've drilled. But since we're three hours into the shift and they're already twenty jobs behind, they just flick their flashlight across the panel and say “looks good" and then sprint away. Can't imagine why our planes keep falling out of the sky.

Seven: Apply the seal to the bracket. P/S 890 is a thick dark gray goop that adheres well to aluminum, carbon fiber, fabric, hair and skin. Once cured, it is completely immune to any chemical attack short of piranha solution, so if you get any on yourself you had better notice quick, otherwise it'll be with you as long as the layer of epidermis it's bonded to. LAM employees who work with fuel tank sealant very quickly get out of the habit of running their hands through their hair.

Eight: Now you wait again. Ha ha, you dumb asshole, you thought you were done with QA? No no, now you put up the job for QA inspection of how well you put the seal on the bracket. Twiddle your thumbs, but now with some urgency. The minute you took the bottle of seal out of the freezer, you started the clock on its "squeeze-out life." For this type of seal, on this job, it's 120 minutes. If QA doesn't get to you before that time expires, you remove your ticket, wipe off the seal, take another bottle out the freezer, and apply a fresh layer.

Nine: Optimistically, QA shows up and signs off on the seal. Well, the "squeeze out" timer started the minute you took the bottle out of the freezer. You've got 120 minutes, and you pulled it out 100 minutes ago. Quickly, you slap the brackets onto the stringer, air hammer the sleeve bolts into position, thread nuts onto the bolts, then torque them down. Shove through the crowd and mark your IP "ready to inspect squeeze out"

Ten: Let out a long breath and relax. All the time sensitive parts are over. The criteria here is "visible and continuous" squeeze out all along the perimeter of the bracket and the fasteners. It is hard to screw this up, just glop on a wild excess of seal before installing it. If you do fail squeezeout, though, the only remedy is to take everything off, throw away the single-use distorted thread locknuts, clean everything up and try again tomorrow.

Eleven: QA approved squeezeout? Break's over, now we're in a hurry again. By now there's probably only an hour or two left in the shift, and your job now is to clean off all that squeezeout. Here's where you curse your past self for glopping on too much seal. You want to get it off ASAP because it'll cure to a rock hard condition overnight and you'll go through hell chipping it off. You'll go through a hundred or so qtips soaked in MPK cleaning up the bracket and every surface of the panel within three feet.

Twelve: Put it up for final inspection. Put away all your tools. (The large communal toolboxes are lined with kaizen foam precisely cut out to hold each individual tool, which makes it obvious if any tool is missing. When you take a tool out, you stick a tool chit with your name and LAMID printed on it in its place. Lose a tool? Stick your head between your legs and kiss your ass goodbye, pal, because the default assumption is that a lost screwdriver is lurking in a hollow "hat" stringer, waiting to float out and damage some critical component years after the airplane is delivered.)

One tool you'll leave on your cart, however, is the pin protrusion gage. There is a minimum amount of thread that must poke outside of the permanent straight shank fastener's (Hi-Lok) nut, to indicate that the nut is fully engaged. That makes sense. But there's also a maximum protrusion. Why?

Well, it's an airplane. Ounces make pounds. An extra quarter inch of stickout across a thousand fasteners across a 30 year service life means tons of additional fuel burnt. So you can't use a fastener that's too long, because it adds weight.

On aluminum parts, it's hard to mess up. But any given composite part is laid up from many layers of carbon fiber tape. The engineers seemed to have assumed that dimensional variation would be normally distributed. But, unfortunately, we buy miles of carbon fiber at a time, and the size only very gradually changes between lots. When entire batches are several microns oversize, and you're laying up parts from fifty plies and an inch thick, you can have considerable variation of thickness on any given structural component. So you had better hope you had test fit all of your fasteners ahead of time, or else you'll be real sorry!

And, if you're really lucky, QA will show up five minutes before end of shift, pronounce everything within tolerance, then fuck off.