Edelweiss almost touches down again immediately after lift-off

[bstolle]

Does it matter?

Of course.

[ATLcrew]

roll stop = full left/right side stick deflection. Due to the sluggish FBW data processing and the low roll rate, you are hitting the stops surprisingly often during normal approaches in gusty conditions.

I may have hit full stop with the stick twice in 10+ years on the 'Bus. But that's just me.

[3WE]

What airplanes are you talking about?

Does it matter?

The airplane doesn’t matter. That being said there’s systems that go into different, gray, overlapping buckets:

1. That’s nasty and insidious and could really trick someone.
2. A potential trap but as long as you aren’t stupid…
3. What the phugoid are they thinking?
4. Oh shit, that SEEMS like a solid idea, but…

I had a buddy on a Value Jet DC-9 at Nashville when the guy pulled the cumulonimbus for the pressurization as they crossed the fence and caused the spoilers to pop.

The resulting landing was excellent and paperwork, including a final report, ensued.


When I read some of this Airbus stuff, it seems kind of weird. (Your aileron authority getting chopped in half…a system where you might learn to let go of the stick right after takeoff)

I don’t object to an nose-down trimmer either, but don’t tell the pilots, attach it to only one indicator, let it run away somewhat relentlessly, and have the system potentially bind up, so you have to dive more to un stick it??? WTP?

[3WE]

[Mildly paraphrased]

Airbus is 100% correct and subjected to unfair criticism.

Boeing really sucks but gets a pass.

https://youtu.be/PEy6968xO-I?si=6hS6juSTVCXPSSOb

[bstolle]

I may have hit full stop with the stick twice in 10+ years on the 'Bus. But that's just me.

That depends a lot on the area of operation and wx.
If you are flying a lot in mountain valleys, Föhn etc. you are likely to experience that more often I guess.

[ATLcrew]

That depends a lot on the area of operation and wx.
If you are flying a lot in mountain valleys, Föhn etc. you are likely to experience that more often I guess.

Don't know where Fohn is, I am a simple man. Operate regularly into places like Vegas, O'Hare, Newark, Reno, Phoenix, etc. Gusty enough?

[Evan]

Evan Sorry, but you know pretty well that this is complete nonsense.

I know pretty well that there is not a single real-world instance of an Airbus "violently pitching up without any way to counteract this. No ECAM messages, nothing". If I've missed something, enlighten me.

As I pointed out previously, there were uncommanded pitch incidents in 2008 on Qantas 72 and 71, both transient, neither particularly violent (.08g), likely due to cosmic interference or (unlikely) interference from a nearby naval communication station. In any event, the problem was caused by a vulnerability in the ADIRU data spike sampling algorithm, which was removed in a software update. Nothing has occurred since.

Nothing else, in reality, resembles your sim experience. Nothing in the design of the A320 explains it. So I must conclude that it was a sim anomaly.

Gabriel once experienced a near-fatal stall in the 747 sim just after take-off. It defied explanation until he learned that it was caused by a sim programming error.

[ATLcrew]

I know pretty well that there is not a single real-world instance of an Airbus "violently pitching up without any way to counteract this. No ECAM messages, nothing". If I've missed something, enlighten me.

I believe he is referring to the Lufthansa 321 that had overspeed protection activate due to bad ADR data. That was the incident that begot the "turn off 2 ADRs and throw the airplane into alternate law" bulletin. There were no ECAM messages in that event.

[3WE]

[…the general subject of moving the side stick to the stops…]

When watching folks land airliners in normal weather, I’m generally impressed with the frequency and extent of the control movement while the view out the windscreen (or from 24A) is seems much calmer.

This is for sticks and steering wheels both.

For really bumpy days, I can imagine sticks and yokes getting very close to the stops and getting totally there during the worst winds.

Yes, ‘imagine’ is a key word.

[3WE]

Gabriel once experienced a near-fatal stall in the 747 sim just after take-off. It defied explanation until he learned that it was caused by a sim programming error.

And he solved it using Tomahawk procedures. I told him 172 procedures would work also, but he told me that was dumb and that it must be done using type-specific procedures.

By the way, did you shove over much like the guys in our long-forgotten topic in the original post?

[Evan]

I believe he is referring to the Lufthansa 321 that had overspeed protection activate due to bad ADR data. That was the incident that begot the "turn off 2 ADRs and throw the airplane into alternate law" bulletin. There were no ECAM messages in that event.

LH1829, the one departing Bilbao? That certainly doesn't fit "violently pitching up without any way to counteract this." It pitched down, reaching -3.5deg, lost a few thousand feet over about two minutes (did not overspeed or exceed G-limits) and the pilots were able to arrest the descent and climb back to level flight with full aft sidestick. And it doesn't fit "fatal logic". The logic did not fail. The sensors were frozen (they were not faulty, just iced-up). And the plane did not kill them. They switched off ADR 1 and 2 and continued to their destination.

Did they ever figure out why the sensors froze up? I know the previous incident involved a ground maintenance genius aiming a pressure-washer directly at the AoA sensors.

[bstolle]

You are completely missing the point. I have no idea if that overspeed incident has been published, or if it happened at all.
Fact is that Airbus discovered this overspeed/pitch up as a potential fatal flaw and hence this malfunction has been added in the sim.
If this malfunction has never happened before, good luck with troubleshooting within a a few seconds and experimenting which button(s) to push.
That's one of the A320 problems. It loves to throw new, previously unknown problems at you.

[3WE]

That's one of the A320 problems. It loves to throw new, previously unknown problems at you.

Just to play Devils advocate are you prepared to say the 320+/- is worse than other aircraft?

737s where the rudder might reverse, or the trim starts cranking down…

DC-9s where the horizontal stabilizer cuts loose to enable inverted flight or the circuit breaker pops the spoilers, and rudder authority goes to hell during reverse thrust?

727s where 40 degrees of flaps can get you in trouble on the drag curve?

DC 10s who’s controls do crazy things depending on cargo latches, flying compressor blades, or engines that smack the upper wing surface.

L-1011s where you can insidiously disconnect the autopilot.

[bstolle]

Plural? MD-80 stabilizer, a single event more than 20 years ago caused by a maintenance error, the same goes for the DC-10 and the "engines that smack the upper wing surface".

A greatly reduced rudder authority happens on most planes with tail mounted engines and effective thrust reversers. Not a problem.
The same is valid for all planes with high lift and hence high drag flaps. Not a problem.

Not sure how these rare examples are connected to the frequent and wildly differing Airbus malfunctions, but I assume these 'Airbus' problems apply to most complex new aircraft.

[3WE]

I’m not sure I’ll agree that Airbus is “wild and frequent”, and that 40 degree flaps are not a problem, especially since engineers undid them on a range of x72x airplanes.

What bugs me more is what Airbus does to pilots- Evan starts spouting systems and modes and guy’s utter stuff like “But I’ve been pulling up the whole time, while neither him nor his partner can keep a mechanically sound plane in a fat, dumb and happy cruise.

Then again, we have pilots who can’t hand-land a 777 on a beautiful Sunday afternoon when low-time student pilots should be out shooting landings.

[Shoulder shrug emoji]