String of commercial airliner mishaps continues...

No sensationalism there.
 
AdRev profit-motivated "original sin" aside, SWA pax have died in the past as a result of engine containment failures. Beyond an honest blade inspection program (as opposed to a regulatory captured one), the cowling components are the critical part of avoiding the former carnage in the first place.

It's fair to suggest the ability to contain is not the sole responsibility of the design, aka the OEM. When panels come flying off like that video shows, that's also on the operator who maintains it (or more pointedly these days, subcontracts to maintain). And it does put into question the presumed ability of the sub-assemblies to do what they're supposed to do, had an engine stage cata-failed before the panels showed themselves to be ill-maintained/handled, as shown by the video.

I think that deserves scrutiny. Not everything is "p&ssy pedestrians and aviation illiterate journos is why we can't have nice things". baby/bathwater type of thing.


/ :devil:adv
 
AdRev profit-motivated "original sin" aside, SWA pax have died in the past as a result of engine containment failures. Beyond an honest blade inspection program (as opposed to a regulatory captured one), the cowling components are the critical part of avoiding the former carnage in the first place.

It's fair to suggest the ability to contain is not the sole responsibility of the design, aka the OEM. When panels come flying off like that video shows, that's also on the operator who maintains it (or more pointedly these days, subcontracts to maintain). And it does put into question the presumed ability of the sub-assemblies to do what they're supposed to do, had an engine stage cata-failed before the panels showed themselves to be ill-maintained/handled, as shown by the video.

I think that deserves scrutiny. Not everything is "p&ssy pedestrians and aviation illiterate journos is why we can't have nice things". baby/bathwater type of thing.


/ :devil:adv
Fair points.
 
Flight crew initially thought problem was an inboard slat separation because both engines were running OK so I don’t think it was a FBO event that triggered the engine cowl separation.
 
AdRev profit-motivated "original sin" aside, SWA pax have died in the past as a result of engine containment failures. Beyond an honest blade inspection program (as opposed to a regulatory captured one), the cowling components are the critical part of avoiding the former carnage in the first place.

It's fair to suggest the ability to contain is not the sole responsibility of the design, aka the OEM. When panels come flying off like that video shows, that's also on the operator who maintains it (or more pointedly these days, subcontracts to maintain). And it does put into question the presumed ability of the sub-assemblies to do what they're supposed to do, had an engine stage cata-failed before the panels showed themselves to be ill-maintained/handled, as shown by the video.

I think that deserves scrutiny. Not everything is "p&ssy pedestrians and aviation illiterate journos is why we can't have nice things". baby/bathwater type of thing.


/ :devil:adv

While true, the article blew right past all the substance, opting for sensationalism. Upton Sinclair it wasn’t.
 
While true, the article blew right past all the substance, opting for sensationalism. Upton Sinclair it wasn’t.
It’s the NY Post. What the heck did you expect? It’s a tabloid rag not worth the paper it’s printed on or the electrons it’s distributed with.
 
SWA pax have died in the past as a result of engine containment failures. Beyond an honest blade inspection program (as opposed to a regulatory captured one), the cowling components are the critical part of avoiding the former carnage in the first place.
No, they're not.

The containment structure surrounds the core of the engine, under all those pipes and wires that were exposed. The parts that separated are just the streamline the outside of the engine nacelle. These are not structural components. Their job is to reduce aerodynamic drag.

Looks like the latches failed and they opened in flight.
 
No, they're not.

The containment structure surrounds the core of the engine, under all those pipes and wires that were exposed. The parts that separated are just the streamline the outside of the engine nacelle. These are not structural components. Their job is to reduce aerodynamic drag.

Looks like the latches failed and they opened in flight.
I can confirm this. The fan case is wrapped in a Kevlar type material and the High Pressure Case and Turbine exhaust cases are all thick and designed to be the containment structure for those modules. The Nacelle does little to nothing for containment.
 
That sheet metal ripped apart like pieces of paper.
Not an engineer, but doesn't seem so benign to me- granted, not a lot of mass- but gotta be a significant amount of energy impacting the horizontal or vertical stabilizer at 150 knots were that to happen...
 
The frequency of events may be pointing in the direction of industrial espionage. Bad actors generating trouble for major airlines within the maintenance system. Bribes and blackmail of front line maintenance. With a dash od DEI for good measure.
 
That sheet metal ripped apart like pieces of paper.
Not an engineer, but doesn't seem so benign to me- granted, not a lot of mass- but gotta be a significant amount of energy impacting the horizontal or vertical stabilizer at 150 knots were that to happen...
A 737 is rarely airborne at less than 150kts. Unless it came off right at rotation, the airspeed was likely significantly higher.

I wouldn't expect the nacelle parts to impact the tail. Airflow is going down, not up, at the point. Even if it did, some dents aren't going to cause any serious problems.

While not common, this has happened many times in the past on all sorts of different airplanes. It's usually a failed, or forgotten, latch.
 
No, they're not.

The containment structure surrounds the core of the engine, under all those pipes and wires that were exposed. The parts that separated are just the streamline the outside of the engine nacelle. These are not structural components. Their job is to reduce aerodynamic drag.

Looks like the latches failed and they opened in flight.
I stand corrected on the outer fairing panels being part of the containment mechanism.

I wouldn't expect the nacelle parts to impact the tail. Airflow is going down, not up, at the point. Even if it did, some dents aren't going to cause any serious problems.
that's exactly what happened to SW 1380.

Which circles back to the macro point I was trying to make: I don't believe these types of incidents ought be treated as lacking cause for scrutiny on the part of the operator. It was impact by a chunk of failed fan cowling and latching mechanisms after blade separation (which was technically contained mind you), the actual mechanical culprit to the cabin window strike and failure, causing the swa fatality. Those latch mechanisms are constantly exercised and perturbed by the airline and its subcontractors, not the OEM.
 
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The frequency of events may be pointing in the direction of industrial espionage. Bad actors generating trouble for major airlines within the maintenance system. Bribes and blackmail of front line maintenance. With a dash od DEI for good measure.
Slow your roll there partner
 
Losing cowling parts have been more of an Airbus 320 series thing the last 10 years or so. It's the one item I go down on one knee for to have a closer look. British Airways even had them open on both sides on a 319 resulting in a loss of hydraulic system and fire when the cowlings started flapping around. Don't know what happened here, on the Airbus it's usually the latches not beeing closed properly after IDG top ups.
 
AdRev profit-motivated "original sin" aside, SWA pax have died in the past as a result of engine containment failures. Beyond an honest blade inspection program (as opposed to a regulatory captured one), the cowling components are the critical part of avoiding the former carnage in the first place.

It's fair to suggest the ability to contain is not the sole responsibility of the design, aka the OEM. When panels come flying off like that video shows, that's also on the operator who maintains it (or more pointedly these days, subcontracts to maintain). And it does put into question the presumed ability of the sub-assemblies to do what they're supposed to do, had an engine stage cata-failed before the panels showed themselves to be ill-maintained/handled, as shown by the video.

I think that deserves scrutiny. Not everything is "p&ssy pedestrians and aviation illiterate journos is why we can't have nice things". baby/bathwater type of thing.


/ :devil:adv
Not to mention that not all engine failures can be contained, and in the case of the woman partially sucked out of the window, that was a contained failure; the offending blade got kicked forward.
Documenting this stuff is my day job ('til the EOM when I retire), and most failures are contained, but there is a lot of energy involved. Most of the responsibility goes to us, the engine manufacturers.
 
One of my very first engineering jobs back in the mid 60’s was to review FAA Yellow Sheets that were brief summaries of incidents of failures on civilian operational flights. I was looking for incidents involving similar engines used by the USAF.

The frequency and severity of incidents weren’t that much different if not worse than today IIRC. And there wasn’t any social media back in the dark ages. I did personally watch a piece of a trailing edge flap depart a BAC-111 while on an Allegheny flight to DCA. Never showed up on any news I saw or read.

Viz a vis containment, engine certification requirements for both civilian and military are basically the same. Fan, Compressor and Turbine blades must not penetrate the engine cases. If they bounce out the front or rear, that’s just bad juju. If a disk fails, it will NOT be contained.
 
The frequency and severity of incidents weren’t that much different if not worse than today IIRC. And there wasn’t any social media back in the dark ages.
Agreed. Service difficulty, TFOA/PDA, and BASH reports and ASRS *have* been around for a while and are very useful but they don't get the spotlight or "Crisis Now!" buzz mass media consumers seem to demand these days. While not everything gets reported they are far more comprehensive (and useful) than e.g. the New York Post.

Nauga,
a reluctant contributor
 
As was pointed out several times, the cowling is just reinforced sheet metal, and to be safe and effective it mush be properly restrained.

Now, judging by what I have found many times on light-aircraft cowlings, the latches and hinges get worn, but the mechanics just keep using them instead of warning the owner that stuff needs fixing. Sometimes the owner will say, "It works, it ain't broke, don't fix it," and I can see airline mechanics and maintenance planners doing the same thing, maybe even being pushed to keep worn stuff going by the bean-counters who actually run the company. It's a false economy, since a failure in flight results in much damage, possibly even an accident, and you scare the daylights out of the passengers. They then pick another airline. Or they don't fly anymore.

It's time to put the engineers back in charge. Sure, it will raise the cost of airline flying, but it has become too cheap anyway. Better more expensive than not available at all eventually.
 
Sometimes the owner will say, "It works, it ain't broke, don't fix it," and I can see airline mechanics and maintenance planners doing the same thing, maybe even being pushed to keep worn stuff going by the bean-counters who actually run the company.
That is not how it works at airlines. The manufacture has established specification for wear and when those specs are exceeded a repair is made. Items that are wearing are tracked and inspected on a schedule to ensure that they remain within the specification.
 
That is not how it works at airlines. The manufacture has established specification for wear and when those specs are exceeded a repair is made. Items that are wearing are tracked and inspected on a schedule to ensure that they remain within the specification.
Of course. That's why the bolts that are supposed to retain that emergency door plug on the 737s were all there, right?

I know all about wear specifications, and I know how those specs are routinely ignored. Why else do we see magneto and alternator and vacuum-pump failures in GA, even in commercial GA? Because the manufacturers' wear specs and periodic inspection recommendations are being completely ignored.

Remember the Alaska Airlines crash in 2000? Where the stabilizer jackscrew had been improperly lubricated and inspected? Sure, the airlines are always in conformity.

Not.
 
Of course. That's why the bolts that are supposed to retain that emergency door plug on the 737s were all there, right?[/quiote]
The bolts were left out because someone made a mistake then the procedures did not generate the need for a QC check when the plug was "opened", like it does when the plug is "removed". That was a systemic problem in the established procedures. The system is supposed to be tolerant of mistakes. In this specific case, it wasn't and that allowed the mistake to go uncaught.

If the specifications are wrong then a problem can get through. That doesn't mean that it's up to the initiative or judgement of the individual mechanics as you said. It is a defined process.

Chances are, the latches weren't properly closed after the last time they were opened. That is the usual result from these types of incidents.
 
The bolts were left out because someone made a mistake then the procedures did not generate the need for a QC check when the plug was "opened", like it does when the plug is "removed". That was a systemic problem in the established procedures. The system is supposed to be tolerant of mistakes. In this specific case, it wasn't and that allowed the mistake to go uncaught.

If the specifications are wrong then a problem can get through. That doesn't mean that it's up to the initiative or judgement of the individual mechanics as you said. It is a defined process.

Chances are, the latches weren't properly closed after the last time they were opened. That is the usual result from these types of incidents.


The cowling in question is a “Fan Cowl” they are quite floppy and flexible when open. They have rods to hold them open for MX. If its windy they are often lowered to the closed position when not activly worked, as they are susceptible to damage when open in gusty conditions.

When that happens it appears that they are latched and secure when they are not.

My lunch money says a mechanic forgot to latch them after lowering.
 
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