Hacker News Reader

Comment by amelius | Hacker News Reader

> some plane crashes occurred after pilots did not secure flaps on wings before takeoff. The FAA required Boeing to have several warning systems to make sure pilots won't attempt a takeoff before the wingtips are locked in the correct position.

And Boeing couldn't imagine that might be a good idea in the first place?

View on HN

Who says that Boeing didn't plan on having warnings? That warnings are required by the FAA in the new rules created doesn't mean Boing wanted to have none, it just says the FAA wants warnings.

It says several planes crashed because of this. I assume they are talking about the same type of planes, perhaps test-models.

There are no test models of the 777X flying yet. And the source material specifically says "flaps", which are not at all the same type of "foldable wingtip" that is being referred to. They refer to very specifically different things.

The planes they are referring to are any other passenger jet, such as Spanair 5022, that crashed due to improper flap deployment.

https://en.wikipedia.org/wiki/Spanair_Flight_5022

Probably a bad assumption given that this model is not flying yet.

The FAA's approach is that any kind of problem that has been seen already needs to be investigated. Planes crashed on some other model because flaps were not locked on takeoff? That type of error goes into a checklist of things to look at. Now everything that needs to be right for takeoff needs to be locked into place!

> Probably a bad assumption given that this model is not flying yet.

I imagine it has flown, just not commercially yet.

It hasn't. Aviation is a hugely popular spectator hobby. Any time a new plane (not even a new model, just a new plane like a 737) rolls out of the factory, it makes the news in these circles. When a new model of plane (like the 777X) rolls out of the factory for the first time, it makes international, front page news. Doubly so when it actually takes it's first test flight.

We're talking about massive passenger jets that are manufactured in the middle of a major metro area in a facility where they give public tours and is watched day and night by hobby and professional photographers alike. These aren't things that they go and "test fly" in secret, even if they wanted to (which they don't, because the 777X's first flight would be such a massive PR event that they would be insane to keep it secret).

You could easily look this stuff up rather than assuming.

To date, the number of 777X aircraft built is zero. Boeing currently hopes to complete the first one late this year or early next year, and is targeting "sometime Q1 2019" for test flights.

The planes crashed because their flap settings were incorrect. Not these winglets/wingtips. Just normal, everyday flaps. And the reference is poorly worded; these haven't flown yet, and the reference is referring to other jet airliners.

AFAIK, this is the first passenger plane with this feature.

Other planes with folding wings have been military, and they may have skipped the redundant locks and warning systems in favor of weight reduction.

There were civilian planes with folding wings, like the Fairchild FC-2 or the Avro Avian. The idea was to make it easier to move them by road or to store them, for instance in a small hangar in Northern Canada for the Fairchild, which was used as a bush plane.

Shouldn’t they automatically lock? In what scenario do you want wings down and unlocked?

I guess it's hard to awnsers have we landed and should we move the wingtips to locked positions? Airplanes afaik have no state machine that says taking off landing taxiing. They may be able to detect it by reading all different systems example landing gear extended altitute from ground radar over 4 feet landing wheel moving etc. But I assume it's too many variables?

It's not just about locking in-place. These warnings will almost certainly include warnings about them being up instead of down, for example.

Reply on news.ycombinator.com