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Comment by genoapol | Hacker News Reader

Without MCAS wouldn't the plane be unbalanced due to engine placement issues and excess weight?

From my understanding, the MCAS system was built to offset these problematic default states that come with using an old body not compatible with the upgrades made. I also heard the weight of these new engines caused wings to develop stress cracks.

Not sure how it could be considered safe without a better designed MCAS system and addressing the other issues.

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You seem to be conflating ideas. jaywalk said it best with:

> It simply handles differently than pre-MAX 737s in certain scenarios

It handles differently than previous 737s due to airframe changes (namely engine position). MCAS was meant to "correct" this for the purpose of skipping re-certification. The airframe isn't fundamentally flawed, the process of certifying it this round was flawed. Which caused Boeing engineers to implement a flawed MCAS system.

I believe this to be a myth. MCAS is not "just" so that it feels like the old 737. Without MCAS, it would not be certifiable.

See for example here:

https://aviation.stackexchange.com/questions/73132/did-boein...

That statement is incorrect. It would be perfectly certifiable with additional pilot training. The killer feature was the theory that MCAS would allow airlines to get away without additional training. Practice proved to be quite different, as is so often the case.

Do you have an authoritative reference for that, stating unambiguously that the plane without MCAS would fulfil all the regulatory requirements for manoeuvring stability in terms of stick force curve slope, for example during a wind-up turn?

(I agree, FWIW, that the plane would by flyable, easily in nearly all flight regimes, and carefully in some flight regimes, without MCAS. But that is not the issue at hand.)

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