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Originally posted by Evan
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But this guys are calling go around (not windshear), flaps 15, positive climb, gear up....
--- Judge what is said by the merits of what is said, not by the credentials of who said it. ---
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Those are predictive windshear alerts, so I suppose the actual escape procedure is not needed unless they actually experience windshear effects. Trouble is, once you've entered a downburst (the first sign I think it the outburst, sudden headwind), it can be too late. I wonder what the policy is at, say, Atlas, Evergreen or Delta....Originally posted by Gabriel View PostComment
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0:57 - I think that one is reactive (boo-deet winshear, windshear, windshear) and flown as a go around
2:11 - This one I think is predictive (go around, windshear ahead), not sure if it was flown as go around or widshear escape
2:40 - again boo-deet winshear, windshear, windshear. I think reactive. Flown as a go around crossing all the t's and dotting all the i's (Go around, toga set, flaps 15, positive climb, gear up)
--- 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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That seems like habit built around a weak safety culture to me. I understand that most windshear is not downburst and that these alerts should give some advance notice but downburst is not something to roll the dice on, and it can occur in close proximity to storm cells, in clear air, not just within them. After a windshear warning, I think retracting flaps is a risky idea until you have reached a safe altitude. Can you see the operators on these videos?Comment
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Thanks for joining the discussion, Gabe and Bobby.
Addressing several comments without quoting.
Gabe: While I agree they should have pulled up more, I disagree that calling “go around” caused the pilots to absolutely refuse to pull up more, and void all common sense. Go around = essentially full power, nose up for really good climb. Wind shear = full power, nose up for MAXIMUM MAXIMUM climb, & try not to stall the thing. They knew they were in a windshear and my opinion remains that they simply fell short on executing extremely critical, seat of the pants, airmanship to fly extremely slow, close to the ground, right next to stick shaker speeds…they weren’t saying, “Geemanitly, we’re going in, but I’m in the middle of the regular go-around procedure, so I can’t pull up more, that deviates from procedure”.
I saw your comment about flaps and gear- I will leave that to you engineers and procedure writers if the payoff in reduced drag compensates for a momentary loss of lift with flap retraction.
I want to fault both you and Evan for dismissing the implications of what it means to be pulling up very aggressively to stick-shaker speeds during already slow speeds, significant turbulence and speed-LOSS conditions. Remember, you are the champion of lateral-control wing-drops, and “it’s better to crash under control”.
The YouTube: On the three shear incidents did any of the pilots do anything but a gentle pull up? Did the stick shaker ever kick in? Even they guy in the nasty soup, there’s minimal yoke movement even though there’s concern in their voices. Dare I suggest that these guys aren’t doing MAXIMUM MAXIMUM performance maneuvering, because they didn’t perceive that these were jumbo splatter level downbursts?
Bobby: You commented on my big question- I’m sure these dudes had “the training” and I don’t have a GOOD answer why they fell short. I don’t default to saying, “Because the stupid pilots didn’t follow the procedure”, like Evan. Is it really that this was a bad ass shear/downburst…is it a super brief period of gentleness on the pull up, or a larger botched opportunity to squeeze more performance out of the thin margins?
Some additional comments:
A long time ago (in a forum some distance away), V-Nav commented on the “Delta191 simulator exercise”. He had a some of interesting comments:
1. You sort of pick up ahead of time that it’s THE exercise.
2. You exit the downburst at ~100 ft AGL, and screaming airspeed when you finally lose the tailwind.
3. It’s a very intense, white knuckle, sweat-inducing exercise.
4. I assume he did these in an MD-80 simulator.
My conclusion: If you know it’s coming and perform perfectly, you barely…barely avoid did dieding.
One more relevant comment (I remember, probably from a place called AD.com and maybe V-Nav again), there was a period where a number of crews damaged “manual” engines by overpowering them on mundane, non-threatening wind shears. FADEC sort of fixed that, but I wonder if this crew wasn’t aware of that concern, given the type and timeframe on this crash?Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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You have the procedure down. Not being in the cockpit, never really know what happened. Gabe, procedure is never ever ever change configuration. (Before gear retracts, doors open! Adds a bunch of unwanted drag.)Originally posted by 3WE View PostComment
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You are talking windshear, right? Becuase go aound I always see (in the YouTube videos) "positive climb, gear up".Originally posted by BoeingBobby View Post
--- 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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Certainly you don't stall, so we stop that topic of conversation. You respect the stickshaker. But gaining or at least preserving altitude is your primary focus here, at the expense of airspeed right down to stall warning if need be.Originally posted by 3WE View Post
In the Airbus (in Normal Law) the procedure is to pull full aft stick, let the alpha protect decide from there.
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No we don’t stop that topic of conversation. (The dot is a period).Originally posted by Evan View Post
That topic is extremely relevant to going slow and pulling up hard in severe turbulence.
Going slow and pulling up is a procedure to stall. Any number of wrong gusts (including the highly likely tailwind) can have you stalled and dropping a wing.
And what the phugoid is the procedure if you get too slow or the stick shaker activates.
If you are getting close to 120 knots and your speed is dropping I’m not faulting a brief shove over or a comment to do so. If you stall you aren’t gaining any precious altitude and if you expect to pull up steeply from a 2000 FPM descent, I’m not faulting a few extra knots.
Your easy chair isn’t going anywhere if your MSFS plane screws in…their chair is going 120 knots and they are almost out of airspeed, altitude and ideas.
Bobby’s joke above: Snide grin achieved.Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.Comment
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Too much AoA. You back off until it ceases and then inch it up again until it triggers, repeat as necessary. If need be.Originally posted by 3WE View Post
One mantra I came across for surviving microburst is 'Don't think. Don't sink". Except, of course, be aware of the situation you're in.
Did I mention that this is not an ideal situation to find yourself in and the better pilots don't go near it?
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Select quotes:
I was describing what happened, and asking questions about how things are supposed to happen. I am not pontificating for pilots to execute a maximum performance windshear escape maneuver at the first hint of a windshear (unless that's what the SOP calls for in which case let's follow the SOP or change the SOP to the one that we want to follow).Originally posted by 3WE View Post
A go around is not essentially full power and nose up for a really good climb. Most go arounds are reduced-thrust go around where the target climb rate is 1000 to 2000 fpm only. And in a go around you immediately call for flaps retraction (to a takoffish position) after adding power (actually the call is "go around, flaps 15", as an example) and for gear up after positive climb. And you target for an initial 15 deg pitch and then fine tune for a specific target airspeed.
Because of that, it is undertandable that, since they were climbing VERY well but the speed was low (especially after retracting the flaps to 15), they wanted to pitch down a bit to gain airspeed. They had an airspeed target.
It is more similar to a take-off with derated thrust than to a windshear escape maneuver, which involves max power, no config changes, an aggressive pitch increase to 20 degrees but honoring the stickshaker (which you expect to trigger), and no vertical speed or airspeed target. It's "climb up as much as you can even if you need to trade some airspeed". You would not lower the nose unless you get a stickshaker or until you are out of the mess. It is more similar to a CFIT escape maneuver than to a go around.
With that in mind, and precisely for the reasons you mentioned, and taking into account that in the vast majority of the approaches abandoned due to windshear such an extreme aggressive reaction is not needed, I understand that pilots fly it as a go-around, unless more aggressive action is needed. I do wonder if that is what the procedure say or if it is a liberty that the pilots take. If the procedure say that it is ok to fly a go around in response to a windshear warning (especially a reactive one), I wonder what is the criteria to trigger the winshear escape maneuver. Because as we saw, flying a windshear escape as a go around may be ok 99.99% of the times but will kill you the other 0.01% if you wait until you lost 30 kts of airspeed and encontered a -2000 fpm downdraft to switch to max power and a more aggressive pull up.
In the videos we see the 2 pilots that get what I think is a reactive windshear warning execute a normal go-around. No aggressive escape is performed, or needed. And you don't want to scare the shit out of all the pax for nothing, or to fly a too-close-to-the-edge-of-the-envelope-possibly-involving-stickshakers maneuver for nothing.
That is why I ASKED a couple of posts ago: "So what is the trigger to execute a windshear escape maneuver?"
In hindsight, the pilots of this accident should have flown a windshear escape maneuver instead of a go-around. But how they wee supposed to know?
--- 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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I would also like to know this. I see it as a dangerous 'liberty', although I would use the word 'complacency'. Downburst happens quite suddenly and can be invisible until that moment. It can be 'wet' or 'dry'. After getting a WINDSHEAR alert, if there is a downburst in your immediate path you are going to fly into it, regardless of whether the warning was predictive or reactive. At that point, I think you will really want that high-lift configuration out and not the gear bay doors. Hopefully, the pilots flying these as go-arounds are intensely focused for the first sign of downburst with one hand on the thrust levers.Originally posted by Gabriel View Post
The procedure I would want would at least require no configuration and maximum thrust until the threat has passed. Pitch could remain in the 15deg range until things get hairy.
The final report concluded that, had they maintained the go-around pitch and applied the commanded full power (unusual for a go-around, I realize) they would have escaped the microburst. It didn't specify with or without grass stains.In hindsight, the pilots of this accident should have flown a windshear escape maneuver instead of a go-around. But how they wee supposed to know?
It was the 'push it down' command and the go-around power setting that doomed them. The pitch command was the captain's error. The lower power setting was the F/O's error.Comment
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