The rules are based on certain models of assessing chances of malfunctions like shorts.

Boeing is claiming that the service time of their wiring setup is sufficient evidence to justify an exception to applying the harsher model.

It is not an incredulous claim, and not a trivial dilemma.

One of planes that prompted this regulation was their own Boeing 747-100 (TWA 800). They should adapt to the new wiring requirement when the regulation went in effect in 2009.

The repair or modification of wiring harnesses is often a risky repair.

I'm not an aerospace expert, but I know that even major automakers usually won't allow their dealers to do repairs to wiring harnesses because it poses too much risk.

Most mechanics are really bad at wiring. I watch them "fix" wires on those TV hotrod shoes, and cringe. (I used to do professional electronic assembly work, and at least I know how to solder properly.)

A popular topic on online car forums is electrical gremlins, almost always from crummy electrical repairs.

Sometimes I see a car where the lights on the rear of the car are wired incorrectly, and I can't understand how this could possibly happen. For example, backup lights (white/clear) are wired the same as the brake lights. The car didn't come out of the factory like that, so at some point someone must have "fixed" it and the result is that some lights come on at the wrong time. I'm amazed someone can look at that and say "yup, my work here is done"

JFYI, those are not necessarily wired incorrectly, car wirings are "queer" a single ground connection (negative/black to frame/body) that has oxidized or however does not make good contact and anything can happen to lights, and tail lights particularly also often suffer from dispersions/bridges in the connectorts due to the effects of humidity/mist[1].

[1] some makes/models are particularly subject to this (FIAT do you hear me?) , and it is very common to need to spray some WD-40 or similar once a year or so on contacts/connectors of tail lights/turn lights.

Could have been an issue with a replacement part. One time I got a replacement headlight that was internally wired backwards from the factory. (High and low beams swapped)

> The repair or modification of wiring harnesses is often a risky repair.

If the repair doesn't make the planes safe according to the regulations they should have been built for, then the planes need to be scrapped.

Safety is achieved by managing risk. Regulations are a derivative description thereof.

If the repair makes the plane meet the letter of the regulations but introduces risks that the regulations didn't consider, you've done a good job at meeting regulations but a bad job at managing actual risk.

The wiring, as it is, is considered unsafe and violates regulation. Boeing is trying to push the false dichotomy between leaving the planes as they are and "fixing" them introducing more risks.

In fact, there is another possibility: that the planes were never airworthy and should have never be flown in the first place and, if they can't be made airworthy, then they should be scrapped.

I am not qualified to judge the relative magnitudes of risk between the cable spacing issue and the rewiring issue. However, it is clear that they each pose some sort of risk.

Although, to play devil's advocate with Boeing's point: if you are to say that those planes are not airworthy because of their cable spacing, then no 737 is airworthy, as the regulation is new.

I think the dilemma is "but money". I agree, the situation is ridiculous.

It's not just money; there is always risk in any hardware rework. If the rework is not done correctly and a plane crashes, even if on a test flight, then your "safety fix" has made the world a worse place.

In this particular case the fact that it is aviation standards for wire separation at issue, when those are typically stupefyingly conservative, means that "doing nothing" may well be the safest course. But I am NOT an expert in this area, so don't trust me!

One way to help make the decision is to try and get money out of the equation. If the two options are "pay for the rework" or "pay a fine equal to the cost of the rework", then any company that opts for the fine might actually believe in that approach.

> there is always risk in any hardware rework

I get your point, but isn't it ultimately about money anyway? If they can wire a plane correctly when they're building it, they surely can rewire a plane later - they might have to remove more stuff, worst case scenario reverting the plane to the same state it would be for an original rewire, and I suppose the reason they don't want to do that is money.

I can't understand the decision to "ship" with a potentially catastrophic failure that would cost many lives otherwise. I don't think this should be a dilemma. IMHO the two sensible options from a regulator point of view seem to be "make the plane safe to fly, and if that's expensive, tough luck" and "don't fly the plane".

It seems to me they could disassemble every Max, re-certify every part as stringently as they would certify a brand new part, throw away any part that was out of spec, then build "new" Maxes from those re-certified parts. (Except doing this would cost huge amounts of money.)

It's not enough to disassemble every Max. This wiring is the same on every single 737, of any model, that is in service. That's a much, much, much bigger effort, plus you'd be tearing apart airplanes that have been in service for decades with no incidents.

They did wire it correctly just the definition of correctly has changed over the last half century since the wiring harness was designed. It wasn't broke so they weren't gonna fix it because fixing things that aren't broke comes with cost and risk that you will break them when trying to fix them.

I think this is over-simplifying the situation. Yes, change the wiring for new builds to meet the regulations but It could well be that retrofitting the existing 800 or so 737's as mentioned in the article could increase the risk over-all.

But I would not trust Boeing to make that calculation and even the FAA's reputation has been dented (which is why I think they are being hard-arses about it) but it could be retrofitting is not the right choice.

I would probably be happier if the FAA and the ESA decided independently whether to allow it.

If money were no object, there would be no aviation industry.

Similarly, if safety trumped all else, there would be no aviation industry.

It sounds like the dilemma might be that facts support not pushing for a repair, but if they go with that they’ll be butchered by the media and the masses.