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Now now, play nicely gentlemen !! It's that or this.....
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If it 'ain't broken........ Don't try to mend it !
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If you ever figure out Boeing's reason for the SEEMING lack of logic with respect to 2 autopilots needed for go-around but only one for a Category I ILS, let me know.Originally posted by Gabriel View Post
I'm sure you agree that there COULD be a valid reason, but, until then, I'm with you: "Wow, that seems illogical, and I still like my fundamentals to be evident in the procedures as opposed to obscured."Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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Just like a manually-flown go-around, I am pulling up aggressively and aggressively challenging Evan...Originally posted by brianw999 View Post
However, I will stop SHORT of causing a stall or pushing Brian over the edge (with a small safety buffer).
In fact, now I will release the back pressure (and trim) and enjoy my 500 feet of altitude and good airspeed and attitude and settle back to a normal fat & happy climb attitude and let this issue go.
Gabriel will have to ask Boeing as to "why".
Are you giving me a hidden message that I can post with only one auto-poster turned on, but need two auto-posters to argue? Trust me, I prefer to manually post.
Good day
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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Originally posted by Evan View PostAnother hint: Your intuition isn't of much help here. It's an engineering issue.Originally posted by 3WEComment
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Brian, I'm trying to make a point here that IS relevent to the thread. This plague of pilot intuition having supremacy over manufacturer's stated procedures continues to result in fatal accidents. Often the reasons for FCOM requirements and limitations have complex rationale that is not readily apparent to airmen. Sometimes it involves systems, sometimes human factors, often the grey area that lies between them. Sometimes it is simply economics and limited capabilities. But the essential thing is that pilots revere the procedures even if they don't understand the 'why' (although I do prefer that they understand the 'why'). That is how we stop these kinds of accidents.Originally posted by brianw999 View PostComment
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Originally posted by Evan View PostOk, give up?Originally posted by 3WE
The B737NG—from the factory**—has only a two-axis autopilot. There is no rudder channel. In a high crosswing landing, autoland can't decrab before touching down. That means undue stress on the landing gear and Boeing seems to allow this up to 20kts of drift in their engineering, above which I suspect the possibility of immediate or latent gear damage exists. Also, in high crosswind, you must immediately disconnect the AP after touchdown to avoid a further nose-down command and a tendency for the windward wing to lift. Will every pilot remember to do this? No.
Now, as an intuitive pilot, this reasoning has very likely has not occured to you and you might correctly assess that the autoflight is capable of handling crosswind above 20kts in flight. You might autoland in a 30kt crosswind and damage the main gear and that gear might collapse on a subsequent landing. I post this to illustrate the difference between pilot intuition and engineering concerns. There are a lot of such examples and we can't expect pilots to know the 'whys' for everything. We want pilots to mainly focus their knowledge on universal aerodynamics, flying skills and procedures. I would prefer that all pilots had a systems deep knowledge but this is never going to happen. But as long as procedures are respected, it doesn't present a significant problem. When intuition begins to trump procedure... that's when the metal gets bent.
Suffice to say, if Boeing places a limitation on something, they had a very good reason. And redundancy and margin-for-error are VERY good reasons.
**Some NG operators have upgraded to a 3-axis autopilot, Rockwell Collins offers such an upgrade. I don't know if the latest factory NG's have also upgraded and I would expect this from the 737MAX. It might remain a 2-axis system to remain price-competitive however.Comment
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What is also relevant, is that at the end of a 14 hour day of HARD flying with your biological clock screwed up, the supremacy of the human mind over complicated, non-intuitive procedures might come up a bit short...Originally posted by Evan View Post
PF: Tonight, for the first time ever, I forgot to turn on the second autopilot when starting the ILS.
PNF (he's tired too): The gusty winds and 15 kt-crosswind component have this approach pretty messed up.
PF: Yeah, let's call it off and go-around, there, I punched the easy-button...
PNF: Yawn, what is that procedure I was reading on JP, that Evan has memorized from days surfing the internet at 0 kts and 0 AGL and plenty of beauty rest...
You always want to denigrate the pilots for deliberately, boldly, wantonly and consciously dismissing your exalted procedures.Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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White WordsOriginally posted by Evan in post #186
Originally posted by 3WE in post #179Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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Indeed.Originally posted by Evan View Post
Perhaps a so-called 20-step crosscheck procedure would be effective?Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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Nevertheless, I would not rely on a 16-year-old version of any manual, especially FCOM. Just free advice.Originally posted by Evan View PostComment
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So, for all you know, the Rostov airplane might very well have had the 3-axis system, correct?Originally posted by Evan View PostComment
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For all we know, the Rostov airplane might have been dispatched with a single functioning autopilot. It looks like the investigation is not going to be forthcoming, although I think it's fair to assume they know what happened by now.Originally posted by ATLcrew View PostComment
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All seems perfectly normal until the underlined part.On Apr 5th 2016 Russia's Ministry of Transport reported that on first approach to runway 22 the aircraft went around, the crew reported a wind shear on final approach, climbed to FL050 then FL080 and entered a hold to wait for improvement of weather. The crew subsequently requested and was cleared to FL150 in the hold. When air traffic control provided information that the visibility was 5000 meters, cloud ceiling at 630 meters/2000 feet, winds from 230 degrees at 13m/s gusting 18m/s (25 knots gusting 35 knots), no wind shear, the crew requested another approach clearance. On final approach at about 220 meters/720 feet the crew went around again and climbed, at 900 meters/3000 feet the stabilizer moved nose down causing the aircraft to stop climbing at about 1000 meters/3330 feet and entering a descent. The aircraft impacted ground about 120 meters from the runway threshold. Preliminary examination results of flight data and cockpit voice recorder do not reveal any evidence of a technical malfunction of engines or aircraft systems or any evidence of an explosion. The investigation is focussing on how the pitch control system works and crew actions during the go around. The captain (ATPL, 5,965 hours total, 2,597 hours on type) was certified for CATIIIa approaches.
So say they they wanted to level off at 3000ft, they applied nose-down trim to level off and ___________________.
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
--- Defend what you say with arguments, not by imposing your credentials ---Comment
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Still seems to me a high probability that somatogravic illusion was behind this.Originally posted by Gabriel View PostComment
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