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-   -   Uncontained engine failure at YSSY (https://www.pprune.org/rumours-news/595753-uncontained-engine-failure-yssy.html)

PEI_3721 15th Jun 2017 10:55

Oh the desire for humans to seek blame / responsibility.
Why not consider what might be learnt; does this event involve design, manufacture, maintenance, operation, etc. As yet not known. Are safety activities in progress?
My interest is in operations with intake flow distortion with acoustic panels. Does this aircraft / engine have restrictions on acceleration in crosswinds, speeds, or recommended handling. And I am not seeking to blame the human, just understanding, and particularly how close to any safety margin modern operations might be.

Airmotive 15th Jun 2017 14:00


Originally Posted by keith williams (Post 9802720)
Now Now. This is supposed to be fun!

If you cannot play nicely then don't play at all

Adjusted appropriately. :-)
The demanding for legal action turned a screw.

lomapaseo 15th Jun 2017 14:40


My interest is in operations with intake flow distortion with acoustic panels. Does this aircraft / engine have restrictions on acceleration in crosswinds, speeds, or recommended handling. And I am not seeking to blame the human, just understanding, and particularly how close to any safety margin modern operations might be
Doesn't appear to be anything more than an inflight shutdown at the lowest level of "unsafe operation" of a powerplant system.

Costly? yes

barit1 15th Jun 2017 18:29


Originally Posted by Turbine D (Post 9800698)
Except for the DC-10 over New Mexico where a CF6 fan blade was liberated and exited forward, walked up the fuselage, broke a window and the passenger was sucked out with his remains never to be found. . .

Well, not quite.

The original CF6 fan assembly was secured together by the spinner, which physically retained the blades in their dovetail slots.

In the above case (a colleague was an investigator on the case) the #3 engine fan case got into a standing wave vibration (like a rung church bell) that scrubbed the fan blade tips a couple times each revolution; this overcame the centrifugal force holding blades in the fan disc. Each time the blade tip scrubbed, aero load on each blade pushed the blade forward a fraction of a millimeter, breaking the spinner loose, and eventually each blade traveled completely free of the disc. #3 fan blades flying every which direction.

One traveled completely under the fuselage to strike the #1 engine accy gearbox. It's fuel pump disabled, that engine flamed out.

Another blade was swallowed by the #2 engine, which coughed and grumbled, but kept running.

Yet another blade hit the RH cabin window at row 10, which depressurized the cabin. The unlucky pax exited via the window.

The aircraft (N60NA, "Barbara") landed at nearby ABQ without further damage.

All of which has virtually nothing to do with the present A330/Trent case.

Vzlet 15th Jun 2017 18:51

N60NA
 
I can't decide if that's a lucky or unlucky plane:
8 months later

lomapaseo 16th Jun 2017 00:05

You left out the guy who fell to his death from the wheel well and the guy who killed himself in the loo all in N69NA as it transited through its owners,

I last saw it at the gate in Pan Am livery at JFK. I called it the devil ship.

I had the earliest Aurora (sp?) model with the identical decals as N69NA but the decal was missing a window on the right hand side ahead of the wing ... go figure

Oro-o 16th Jun 2017 06:17


Originally Posted by Turbine D (Post 9800698)
Except for the DC-10 over New Mexico where a CF6 fan blade was liberated and exited forward, walked up the fuselage, broke a window and the passenger was sucked out with his remains never to be found.

Also, there was at least one incident where the shaft to the fan on an RB211 engine sheared releasing the entire fan which spun out forward and away from the aircraft.

There were a few things here that surprised me, namely the forward ejection of blades, "walking" along the fuselage of said debris, and the lack of retrieval of the victim after all this time. So I looked into them. They are not as stated.

N60NA/National 27 lost a passenger on that flight. His seat, 17H (from the FAA report), based on both contemporary 2-class domestic DC-10 configuration AND photographs of the airframe after landing, show the broken window and his location is completely orthoganal to the fan blades. There are score marks a few feet forward of the window and six to eight feet below, but more logically explicable by deflection of additonal blade ejecta from the inboard wing, which shows significant damage. None of the physcial evidence I could find supports forward ejection of the blades or "walking" along the fuselage.

The remains were recovered two years later (Winter 1975/76) during construction of the VLA radioastronomy facility. They were not "never to be found."

What is really interesting is if the flight crews' unsanctioned flight tests at the time of the incendent contributed to it. The FAA report is an interesting read and surprisingly circumspect on that. Hopefully a DC-10 FE could shed light on that.

lomapaseo 16th Jun 2017 13:42


orthoganal
a very big word that doesn't apply to a rotating body at the instant of release.

After release there are many conditional elements to consider, namely whether the fan case is present and whether other adjacent blades are still present. All of this varied in the N60NA incident.

and don't ignore windage if the release has to exit through any kind of shielding that slows it down.

barit1 16th Jun 2017 17:34

My edits:


Originally Posted by barit1 (Post 9803124)
. . .
Another blade was swallowed by the #2 engine, which coughed and grumbled, but kept running.

As others have pointed out, the blades at high energy went orthogonal (or radially outward if you prefer). As such they would not intersect the #2 inlet; it must have been low-energy debris i.e. cowl pieces.

Besides, I'm sure that had the #2 fan had swallowed an extra blade, the result would be a dead-stick landing.


Yet another blade hit the RH cabin window at row 10, which depressurized the cabin. The unlucky pax exited via the window.

Row 17 per the report, not row 10.

megan 17th Jun 2017 02:27


It's fuel pump disabled, that engine flamed out
Another correction barit, the engine did not flame out. Its oil tank was punctured and continued to lose oil for the remainder of the flight, as did its hydraulic system, but the engine operated throughout. Additionally, the wiring for the fuel flow transmitter and generator were severed.

it must have been low-energy debris i.e. cowl pieces
A small piece of fan blade was found embedded in the forward section of the #2 engine inlet cowl, and two of the fan blades had leading edge damage. Boroscope inspection found three compressor blades had small nicks.

ThreeThreeMike 17th Jun 2017 07:32

Regarding N60NA, two of the three hydraulic systems were comprised and the reservoirs emptied when the wing leading edge was damaged.

While this was mentioned in the NTSB document, there was no significance at all attached to the implications. As we all know, it would take some years before another uncontained failure on a DC-10 resulted in the loss of all three.

parabellum 18th Jun 2017 02:16

Just a bit of add-on. Hull insurance does not include mechanical breakdown of the engine, there is specialist engine only cover available in the insurance market, the engine cowls are considered a part of the airframe. Hull insurance does, I think, cover FOD in an engine and in this case the engine cowl would, I think, be classified as FOD. Anyone in the current insurance market will know for sure. Any legal activity, possibly between underwriters, will take place behind the scenes and you are unlikely to ever hear of it.

ThreeThreeMike 18th Jun 2017 06:20

That's interesting. I didn't know there were underwriters for FOD damage.

lomapaseo 18th Jun 2017 15:26

Big operators self insure up to certain levels

Small operators farm out some maintenance and/or insure at lower levels.

Most crossover points have to do with source of damage as well.
Some FOD is argued as engine generated and versa-visa.

Inlet cowls have often been covered as above the self insurred level. for some operators.

Even the biggest operators often insure for reverser and/or pylon involvement in engine damage incidents.

the fine print rules and subjective judgments are sought

SeenItAll 19th Jun 2017 21:51

Not that it is directly relevant to this incident, but the NTSB report on the National Airlines DC-10 N60NA accident over New Mexico is incredibly frightening in terms of the malfeasance it suggests occurred by the airline's management, its maintenance staff, its flight crew and (somewhat) its cabin crew. I certainly hope that now 40+ years on, procedures and professionalism have improved substantially. That National Airlines is now dead does not seem saddening. See: https://www.ntsb.gov/investigations/...ts/AAR7502.pdf


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