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UPS Cargo Jet Crashes Near Birmingham Shuttlesworth International Airport
He's talking about core-lock, a previously little-known phenomena that can occur when a couple of out-of-work rodeo clowns get a job flying turbofan airplanes without seeming to know the first thing about them.
Core-lock in for engines. I want to know about the statement you made,
"737 episodes where supercooling caused the tail surface to do the opposite of the pilot input".
"737 episodes where supercooling caused the tail surface to do the opposite of the pilot input".
Ummmm the original poster (not Bobby)....he's talking about 737 rudder reversals...let's not be collectively dense here.
As to EXACTLY what happens, Gabriel will have to explain, but I was thinking hot, dirty hydraulic oil helped (not cool oil) (and I could be wrong too).
...all I know is that the rudder actuator had some sort of booster control which under some very exacting circumstances- it worked "in reverse" of what was intended and indeed a huge segment of engineers did not figure this out.
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
...and it was laced with several bad pilot actions.
But, yeah, engine core lock was a contributing factor.
Bad pilot actions:
-Probably screwing around a lot on the climb out in an unprofessional matter (for the record, I actually think a climb contest is cool and OK, but you win it by flying precisely and professionally- not jacking around with zoom climbs).
-Getting to 410 in a bad energy state (behind the power curve, slow speed, high AOA).
-Sitting there while the plane (autopilot) spent a LONG time stalling itself.
-Allowing it to become a full stall (which often causes flameouts in rear-engine planes).
-Doing lots of wrong restart procedures (core lock was involved in the restart problems- following the instruction manual probably would have helped a lot).
-Not declaring the problem or asking for help (there may have been an OK airport within gliding distance- although, in their defense, weather was challenging and there may not have been a good alternative).
Les règles de l'aviation de base découragent de longues périodes de dur tirer vers le haut.
Core-lock in for engines. I want to know about the statement you made,
"737 episodes where supercooling caused the tail surface to do the opposite of the pilot input".
This is just pure rubbish!
Well, first of all, I didn't make that statement.
Secondly, he posted a link to Pinnacle 3701, a crash that involved core-lock. (I think he did that for my benefit re: Gabriel's reference).
I think Economy Class is referring to the ETEB finding during the 737 rudder PCU testing that ice accumulation can lead to rudder malfunction (though I know nothing in that finding about supercooled water). That's not pure rubbish, but hopefully it is no longer true.
Secondly, he posted a link to Pinnacle 3701, a crash that involved core-lock. (I think he did that for my benefit re: Gabriel's reference).
I think Economy Class is referring to the ETEB finding during the 737 rudder PCU testing that ice accumulation can lead to rudder malfunction (though I know nothing in that finding about supercooled water). That's not pure rubbish, but hopefully it is no longer true.
Probably easy to go back and find it. An experienced pilot tried to use approved techniques to get out of a dive not knowing he was making it worse. It took some time to establish a mechanical malfunction that caused the dives.
As for core lock, the explanation shows that you can't depart much at all from an exact protocol and hope to recover. You can try to minimize it by calling them "rodeo clowns", but they had licenses to be in the cockpit. We are all armchair critics until we complete the same certification. And flying has always involved above average discretion, from all that I know. I can make a lot more mistakes on the highway and survive. The parts of my car can be exceptionally crappy and the vehicle still driveable. There's no question mistakes were involved. But I maintain that mistakes in a cockpit are far more costly than in the driver's seat of other transportation technologies. Its like a "gotcha assembly" waiting for humans to act human.
Probably easy to go back and find it. An experienced pilot tried to use approved techniques to get out of a dive not knowing he was making it worse. It took some time to establish a mechanical malfunction that caused the dives.
As for core lock, the explanation shows that you can't depart much at all from an exact protocol and hope to recover. You can try to minimize it by calling them "rodeo clowns", but they had licenses to be in the cockpit. We are all armchair critics until we complete the same certification. And flying has always involved above average discretion, from all that I know. I can make a lot more mistakes on the highway and survive. The parts of my car can be exceptionally crappy and the vehicle still driveable. There's no question mistakes were involved. But I maintain that mistakes in a cockpit are far more costly than in the driver's seat of other transportation technologies. Its like a "gotcha assembly" waiting for humans to act human.
They had licenses to be in the cockpit and a job to do, namely to ferry the aircraft back to home base, not play CRJ Top Gun because there were no passengers in the back. The whole flight reeks of this juvenile and completely unprofessional attitude, that ended up getting them killed. Core lock was a consequence of their initial transgressions, not what led to their demise and the loss of the aircraft. They didn't even correctly perform the restart procedure.
As for core lock, the explanation shows that you can't depart much at all from an exact protocol and hope to recover. You can try to minimize it by calling them "rodeo clowns", but they had licenses to be in the cockpit.
But they didn't have the training to be in that cockpit, and that is the only thing that is going to prevent this kind of thing from happening. If they were properly trained, they wouldn't have got into a stall in the first place (they made so many mistakes here it is almost slapstick comedy if it wasn't so tragic and terrifying to think about), and if they were part of a good safety culture, there would never have been a "four one oh club".
Core lock wasn't well understood then, but it should be now. In the event of an in flight engine relight pilots are now supposed to be aware of the importance of N2 levels. But how many are still not trained for this because their management feels it is beyond their need-to-know?
The NTSB plans to fly another UPS A300 on the approach to Birmingham in the next few weeks to observe the company’s procedures for using the Runway 18 localizer approach, says Sumwalt.
It sounds to me like they were willfully trying to save an unstable non-precision approach below 1000'. I'm guessing all UPS pilots know this as a violation.
For interests sake here's a bit of guidance from IOSA.
Regarding rates of descent at low level, IOSA states:
FLT 3.11.50 The Operator shall have guidance that requires flight crews, when operating an aircraft at low heights AGL, to restrict rates of descent for the purposes of reducing terrain closure rate and increasing recognition/response time in the event of an unintentional conflict with terrain.........The description of GPWS sink rate mode does not address the specifications of this provision.
My operator uses: The following values for the rate of descent below FL200 shall not normally be exceeded:
• 5000 fpm down to an altitude of 5000 ft above the terrain.
• 3000 fpm down to an altitude of 3000 ft above the terrain.
• 2000 fpm down to an altitude of 1000 ft above the terrain.
• 1000 fpm below 1000 ft above the terrain.
For use of constant descent IOSA states:
FLT 3.11.66 The Operator shall have a policy and procedures that require and ensure the proper use of a stabilized constant descent profile during the final segment of a non-ILS (including nonprecision) approach. Guidance
Constant descent profiles during the final segment of an approach might be accomplished by various means to include:
Vertical Navigation (V-NAV);
Flight Path Angle (FPA);
Constant Path Angle (CPA);
Constant Angle Non-Precision Approaches (CANPA);
Other methods that provide a stabilized constant path angle for the final segment of a non-ILS approach
My operator states: NON-ILS APPROACH – CONTINUOUS DESCENT
A continuous descent approach is a manoeuvre, commencing at the nominal descent point and ending at touchdown, with appropriate rates of descent similar to those used when following a three degree approach path.
It is Company Policy that a stabilised continuous descent approach be flown on the final approach segment.
When flying a continuous descent approach, a missed approach shall be initiated on reaching the MDA +50 ft or MAP, which ever occurs first, if the required visual criteria are not met.
Note: A missed approach turn should not be commenced until the MAP is reached (or as
specified on the approach chart).
As far as I'm aware UPS are a subscriber to the IATA Operational Safety Audit.
This discussion raises a question for me. With the ever-present possibility of a plane aborting and going around, does air traffic control factor that in when it clears a plane to land? It needs air space for the plane to do its go around, so it can't let other flights be in the way.
This discussion raises a question for me. With the ever-present possibility of a plane aborting and going around, does air traffic control factor that in when it clears a plane to land? It needs air space for the plane to do its go around, so it can't let other flights be in the way.
Of course. Did you see the dotted line that shows the missed approach procedure in the approach plates? That part of the air is left available for a go-around every time an airplane is approaching.
Not that there have never been conflicts because of a go-around that was badly handled by the pilot or ATC, though.
--- 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 ---
Of course. Did you see the dotted line that shows the missed approach procedure in the approach plates? That part of the air is left available for a go-around every time an airplane is approaching.
Not that there have never been conflicts because of a go-around that was badly handled by the pilot or ATC, though.
Of course. Did you see the dotted line that shows the missed approach procedure in the approach plates? That part of the air is left available for a go-around every time an airplane is approaching.
Not that there have never been conflicts because of a go-around that was badly handled by the pilot or ATC, though.
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