737 Engine comes of wing in Cape Town

[James130]

Just heard on the radio that a Nationwide 737-200 lost an engine after take-off. Apparently the bucket deployed and shortly after that the engine dislodged from the wing and hit into the runway. The aircraft got away ok and is currently circling to burn off fuel and plan the return landing.....

[F4F]

Mmmhhhh
Having the reverser bucket(s) open on an engine during the take-off and then loosing the whole engine must be a nice piece of rodeo :eek:

Well done guys, all my sincere wishes for a successful outcome :ok::ok::ok:


live 2 fly 2 live

[Upgrade Please]

On-line news here - but fairly inconclusive as to what's going on
http://www.news24.com/News24/South_Africa/News/0,,2-7-1442_2216890,00.html

Surely it can't have been too bad if the runway was only closed for 10 minutes?!? Or could this be a bit of 'seat of the pants' press management?

More to come methinks...let's hope everyone gets on the deck safely

[Wodrick]

link here http://www.news24.com/News24/South_Africa/News/0,,2-7-1442_2216890,00.html

Safe return, no injuries, well done all

[antic81]

Not sure whether they lost the whole engine or just part of it, as eye whitness accounts are sometimes not all that accurate, glad to hear it turned out well though!

I heard that it can be almost unrecoverable for a 200 to have an engines reverse buckets become unlocked just after take off?( I cant imagine it would be a good thing on any twin)
I imagine the guys must've had their hands and feet full!

Well done to the crew!

[BOAC]

It is difficult - I recall it was a Sim exercise on the 200 in DanAir and the climb rate was not a lot:)

[Sallyann1234]

"They took off and left the engine behind," he said.
:E:E:E

[IGh]

Judging from earlier cases, readers should be skeptical about any ThReverser interaction before this latest ENGINE SEPARATION. See history of B737-200 cases.

Cone pins were used on B737-100s and -200s, and B727s (fuse pins employed on B747, B767, B757, and B737-300/400/500s).

NTSB sought hardware changes. A safety cable system had previously been used to hold engine after failure of primary structure -- then secondary support structure designed and installed (which also fractured in the DAL case).

[See also B707 and B747 cases where #3 Eng separates and then spears the #4 Eng.]

= = = // = = =

Delta B737-200 7Jan92 DFW. Engine separation on takeoff. After T/O at 200' breakaway safety bolts called "Cone Pins" sheared for right engine. Engine bounced on grass on right side of runway.
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001211X13985&key=1
... FTW92IA055 ....
... DELTA AIR LINES ...
... Tuesday, January 07, 1992 in DFW ...
... BOEING 737-232 ... N322DL ...

THE RIGHT ENGINE SEPARATED ... CLIMBING THROUGH 200 FEET AFTER TAKEOFF. ... UNEVENTFUL LANDING ...

ENGINE SEPARATION WAS THE RESULT OF THE FAILURE OF THE AFT CONE BOLT AND THE ENGINE SECONDARY SUPPORT ASSEMBLY. THE AFT CONE BOLT FAILED AS RESULT OF A PREEXISTING FATIGUE CRACK, WHILE THE ENGINE SECONDARY SUPPORT ASSEMBLY FAILED AS RESULT OF THE DYNAMIC LOADS THAT EXCEEDED THE DESIGNED CAPACITY OF THE MOUNTING BOLTS.

THE TWO FORWARD CONE BOLTS FAILED IN OVERLOAD AS THE ENGINE SWUNG FORWARD DURING THE SEPARATION SEQUENCE.

METALLURGICAL TESTING REVEALED THAT THE FATIGUE OF THE AFT CONE BOLT WAS A RESULT OF LUBRICANT INADVERTENTLY INTRODUCED INTO THE CONICAL SURFACE OF THE CONE BOLT.

...Board determines the probable cause ...
THE FAILURE OF THE AFT CONE BOLT AS RESULT OF PREEXISTING FATIGUE CRACKING DUE TO IMPROPER MAINTENANCE, AND THE FAILURE OF THE SECONDARY SUPPORT STRUCTURE AS A RESULT OF LOADS THAT EXCEEDED THE CAPACITY OF THE ATTACHING HARDWARE AND THE CRUSHABLE HONEYCOMB CORE.

= = = // = = =

Piedmont Airlines B737-200, 20Jan89, right engine separated from aircraft after T/O at Chicago. Newly designed secondary support structure had not yet been installed.
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001213X27558&key=1
... CHI89MA046 ....
... PIEDMONT AIRLINES
... Friday, January 20, 1989 in CHICAGO, IL ...
... BOEING 737-201 ... N242US ...

AN IN-FLIGHT TEARAWAY OF THE RIGHT ENGINE (FROM THE RIGHT WING) OCCURRED AS THE AIRPLANE LIFTED OFF FROM THE RUNWAY. ... CONTINUED THE TAKEOFF ... RETURNED ...

AN EXAM OF ITS WING & SEPARATED ENGINE REVEALED THE AFT CONE (ENG MOUNTING) BOLT HAD FAILED FROM FATIGUE, THEN THE TWO FORWARD CONE BOLTS FAILED FROM DUCTILE OVERSTRESS.

A RAISED MECHANICAL DEFORMATIVE WAS FOUND ON THE CONICAL SURFACE OF THE AFT BOLT. THE DEFORMITY WAS INDICATIVE OF DAMAGE PRODUCED PRIOR TO OR DURING ASSEMBLY OF THE CONE BOLT IN THE ISOLATION MOUNT. A MATCHING CAVITY WAS NOTED ON THE ISOLATION MOUNT. THERE WAS EVIDENCE THAT THE MECHANICAL IRREGULARITY RESULTED IN A NONUNIFORM FIT WHICH ALLOWED THE TORQUED FITTING TO LOOSEN DURING CYCLIC LOADING.

AD 88-01-07 REQUIRED THAT ULTRASONIC INSPECTION OF THE CONE BOLTS BE PERFORMED AT INTERVALS NOT TO EXCEED 600 CYCLES. AN ULTRASONIC INSPECTION OF THE BOLTS HAD BEEN ACCOMPLISHED ABOUT 330 CYCLES BEFORE THE ENGINE SEPARATED.

... Board determines the probable cause ...
PREVIOUS DAMAGE TO THE AFT CONE (ENGINE MOUNTING) BOLT, WHICH RESULTED IN MISMATCHED SURFACES BETWEEN THE BOLT AND ISOLATION MOUNT, LOSS OF TORQUE DURING CYCLIC LOADING OF THE MOUNTING BOLT, AND SUBSEQUENT FATIGUE FAILURE OF THE BOLT.

= = = // = = =

US Air B737-200 PHL 5Dec87 #2 engine separated shortly after takeoff. Cracks caused by metal fatigue in one of three bolts; after rear bolt failed the two forward bolts and support cable failed in overload. http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001213X32769&key=1
... NYC88FA050 ....
... USAIR
... Saturday, December 05, 1987 ... DEPTFORD, NJ ...
... BOEING 737-2B7 ... N319AU ...

DRG TKOF, AS USAIR FLT 224 WAS CLBG THRU 4000', THE ACFT YAWED/ROLLED RGT. SIMULTANEOUSLY, THE CREW NOTICED THE #2 THROTTLE SLAM/LOCK TO THE IDLE PSN & A CONTINUOUS AIRFRAME BUFFET BEGAN.

SOON THEREAFTER, THE #2 ENG SEPD FM THE ACFT & THE BUFFET STOPPED.

THE ENG IMPACTED IN AN OPEN FLD, 6 MI FM THE ARPT.

JUST BFR IT SEPD, A PAX SAW THE AFT END OF THE #2 ENG MOMENTARILY DROOP ABOUT 30 DEG.

AFTER ENG SEPN, THE 'B' HYD SYS LOST PRES & THE TE FLAPS WOULD ONLY EXTD 10 DEG.

THE ACFT WAS LNDD SAFELY AFTER AN EMERG GEAR EXTN & DIFFERENTIAL BRAKING WAS USED FOR STEERING.

AN EXAM REVEALED THE AFT MOUNT CONE BOLT FOR THE #2 ENG HAD FAILED FM FATIGUE THRU THE THREAD RELIEF UNDERCUT RADIUS. FATIGUE CRACKS HAD INITIATED ON DIAMETRICALLY OPPOSITE SIDES OF THE RADIUS. SUBSEQUENTLY, THE FWD MOUNT CONE BOLTS & SECONDARY SUPPORT CABLE FAILED FROM OVERLOAD.

... Board determines the probable cause ...
ENGINE INSTALLATION, MOUNTING BOLT ..FATIGUE

= = = // = = =

"Southwest 223" / 3Jan86 B737-2H4, after T/O from Love Field (Dallas), Rt Engine rear mount Cone Bolt sheared, mount failed and restraining cable broke; leaving the engine attached by only the two fwd mount bolts; returned safely. [AWST 124:31 Ja 13'86, photo.]

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20010110X00187&key=1
... FTW86MA030
... SOUTHWEST ...
... January 03, 1986 in DALLAS, TX
... BOEING 737-2H4 ... N86SW ...

THIS INCIDENT OCCURRED WHEN THE NO. 2 ENGINE EXPERIENCED AN AFT ENGINE MOUNT CONE BOLT FAILURE AND THE SUBSEQUENT FAILURE OF THE SECONDARY SUPPORT LINK (STAINLESS STEEL CABLE).

THE FAILURE OF BOTH AFT ENGINE SUPPORT ASSEMBLIES DURING THE TAKEOFF ROLL ALLOWED THE AFT SECTION OF THE ENG TO HANG DOWN TO WITHIN 4' [sic, transcription err] OF THE GROUND. AS A RESULT, THE NO.2 THRUST REVERSER ACTUATOR ASSEMBLY DRUG THE RUNWAY ON ROTATION.
... RETURNED ... LANDED...

METALLURGICAL EXAMINATION OF THE CONE BOLT REVEALED THAT IT FAILED AS A RESULT OF FATIGUE, MOST PROBABLY DUE TO IMPROPER INSTALLATION OF THE BOLT, SPECIFICALLY, THAT IT WAS UNDER TORQUED WHEN THE OPERATOR RE-INSTALLED THE ENG.

THE SAFETY CABLE FAILED AS A RESULT OF OVERSTRESS, PROBABLY INDUCED WHEN THE ACFT ENCOUNTERED A ROUGH STRETCH OF RUNWAY DURING THE TAKEOFF ROLL.

... Board determines the probable cause ...
ENGINE INSTALLATION, SUSPENSION MOUNTS .. FAILURE, PARTIAL
... FATIGUE ... SEPARATION ... OVERLOAD ... UNDERTORQUED
MAINTENANCE, INSTALLATION .. IMPROPER ...

Contributing Factors ... RUNWAY / LANDING AREA CONDITION ... ROUGH /UNEVEN

[757_Driver]

This is 3rd hand heresay, so treat it as such, but my mother is in cape town waiting for a nationwide flight back to Jo'burg. She has just texted me. Apparently some from her tour group were on the affected flight.
My mums words are that aircraft landed back after approx 1 hour. Passengers are all in counseling at the moment, airport is closed. I texted back to ask what the problem was, her reply was "Serious, Engine fell off!".

Sounds like top marks to the crew for bringing it back in one piece. Well done guys (or gals) :D:D

[antic81]

The thread is also running in the Africa forum, no pictures up there yet, would be very interested to see some pictures of the aircraft in question.

[cwatters]

http://www.iol.co.za/index.php?set_id=1&click_id=139&art_id=nw20071107194353660C626321

Extract:

"I heard this huge bang, and he said, that's our engine that's just fallen off. I couldn't believe it. He had to repeat it to me," she said.

"The plane started to shake a bit, but what was amazing was the staff and passengers: everybody was so calm. There was no hysteria, no nothing, it was amazing.

"The guy next to me seemed to know something about planes. He said, don't worry: the plane will go with one engine. So I thought, that's okay."

She said that while the plane was making a wide turn and dumping fuel, the cabin crew took the passengers through the emergency procedures, getting them to take off their shoes and practice bending down.

"They didn't know what to expect. It could have been a hard landing. It could have been anything," she said.

"It's quite scary: flying around quite a lot, you don't listen to the emergency procedures. Suddenly you realise, I need to know what to do.

"But when we landed it was a soft landing, like you would think there was nothing wrong with the plane."

She said that when the plane had come to a stop surrounded by fire engines, the pilot walked into the cabin, and all the passengers cheered.

But she admitted she herself had been "very panicky" during the landing.

"I don't think I've ever been so scared in my life, ever," she said.

At 7pm, having declined counselling, she was waiting for a British Airways flight to Johannesburg.

"We'll see how that goes. I hope they've got a drink, because I need one now," she said.

[Avman]

At 7pm, having declined counselling, she was waiting for a British Airways flight to Johannesburg.

"We'll see how that goes. I hope they've got a drink, because I need one now," she said.

That's my kind of gal. Stiff upper lip, "carry on chaps". Good for her :D

[Feline]

Have listened to three eyewitness reports - all passengers - two of whom actually watched the engine fall off. No-one said anything about the thrust bucket deploying - and I rather think they would have noticed (and commented) if it had.

One broadcast comment was that most of the Nationwide pilots are very experienced ex-SAA pilots - and can't help but think that helped matters.
Also -- they didn't use the emergency slides for evacuation - waited about five minutes then disembarked down steps.

Interesting (referring to IGh above) that it's always the Right engine that falls off - anyone care to comment on that?

Sounds like the crew did what they had to - well done to them!:D:D:D

[antic81]

Avman,

Thats because she is from Jo-Burg, have you ever driven on the airport road?:}

I think it makes more sense that the engine separated rather than the buckets becoming unlocked, although we shall see.
IGh that made for some interesting reading, thanks.
I'm not sure what the state of maintenance is like at Nationwide?

[tristar 500]

Regardless of the discussion about cone bolts etc, just think of the inertia of a JT8 at T/O power!! The gyroscopic effect would send it miles until it ran down!! :=

Tristar 500

[radioexcel]

:uhoh:Watching something like this happening is seeing but not believing...even after 30+ years in the job, it still rattles you.

I must applaud the crew:D:D:D:D They kept the plane flying under these trying and difficult conditions with drizzle rain and a cloud base of 900ft running IMC just after the incident while trying to keep the A/C flying. No time to dump fuel as it was spilling on its own. They made it back by the grace of God. It had to land...that is why the runway was cleared of rubble in such a short time(not 10 mins but 20 mins)

Engine, cowling and other parts still lying next to the runway.

Once again....brilliant flying by the pilots:ok::ok::ok::ok:
RE

[KeithO]

Whatever the cause, well done to the crew

[BRL]

http://www.news24.com/Images/Photos/2007110800493707_plane220.jpg

[javelin]

Yep, that fell off by the looks of things :ok:

[lomapaseo]

Regardless of the discussion about cone bolts etc, just think of the inertia of a JT8 at T/O power!! The gyroscopic effect would send it miles until it ran down!!

Well we do have lots of experience good and bad with this sort of thing, some of which IGH has already posted.

Engines which toss their cookies before breaking off have already lost much of their inertia by the time that they fall away so no big gyro there (Kalita B747).

Engines which are perfectly good and fall away (fatigue of pylon mounts) have enough fuel left in their guts to last about 5 secs. The smaller engines (on the B737) simply fall away even at takeoff/early climb power having been found pretty much on the runway heading within walking distance from the point of departure.

The larger fan engines like the JT3D on the B707 act just like the JT9D on the B747 (El AL, CI) and being released due to pylon mount fatigue lift up and snap to the right into the outboard engine due to gyro loading effects within the first 5 sec.

[777Contrail]

This wasn't a "normal" separation where the securing bolts shear. This looks like the entire pylon came out!

How are these aircraft maintained/inspected?

[Ern DSM]

So now that this has happened I hope people are going realize that this old 737 should be taken out of service, I mean really now, look at all the other airlines, they using newer models now. Besides when I lived in Jhb whenever a really noisy plane took off and I looked outside it mostly always was the 737.

[nugpot]

Besides when I lived in Jhb whenever a really noisy plane took off and I looked outside it mostly always the 737.

Or a 727, or a DC9, or an IL-76, etc. When in Africa............

[QCM]

If the engine had to fail,and if of course there is no dramatic wing or tail structural damage,if the balance can be maintained,it's better to leave a couple of unecessary tons of dead metal on the ground,you'll be lighter for the initial climb.:}
Then is it usefull to spend precious time burning extra fuel,considering the dire emergency and the unfortunate "loss of weight"??:rolleyes:

[757_Driver]

This wasn't a "normal" separation where the securing bolts shear. This looks like the entire pylon came out!

The 732 doesn't have a pylon as such does it? just the engine slung on the wing.

Then is it usefull to spend precious time burning extra fuel,considering the dire emergency and the unfortunate "loss of weight"??

I don't know the 737 systems, but I would imagine such a separation would probably also cause significant hydraulic, fuel and electrical system damage, much more so than a failed engine.
I wouldn't be surprised if that little lot didn't take a long time to work through all the checklists.
As long as the aircraft is flying, there is no fire, fuel isn't peeing out at a huge rate, and everything is stabalised - i.e no further hydraulic or electrical degradation after the initial damage, then where is the urgency to get back on the ground?
Better to make sure you've run through everything, maybe also 'fly' it around a bit in a few configs and speeds to check everything else on that wing is still where it should be.
ISTR that where a separation has lead to a total loss (DC10, 747 Amsterdam) it was mainly due to some high lift devices being damaged, or retracting due to the hydraulic loss and when the speed came back the aircraft bascally dropped below the new VMCA. Why rush back and risk that scenario just because you were too hurried to work all the QRH items?

[nugpot]

Then is it usefull to spend precious time burning extra fuel,considering the dire emergency and the unfortunate "loss of weight"??
Apparently, they lost hydraulics with the separation and were also losing fuel the whole time. The gear stayed down due to the loss of hydraulics.
There is also an account from someone listening in to the radio transmissions between the tower and the a/c.

[Hurkemmer]

Sounds like a good engine out drill, continued the climb out, circled and burned fuel off, acsa (airport chaps) cleared the crumbs and put her down in one piece. Star performance ek se....

[antic81]

Ern DSM:

The problem is if they were to ground all the 737-200 Adv out there, it would leave the low cost companies with a desperate shortage of machines to operate!
They are mostly old SAA airframes I believe, cheep to purchase but I would imagine rather expensive to operate, and the older they get, the more expensive they will get, I feel that sooner or later these low cost airlines will have to have a rethink, although I think Nationwide is in the process of upgrading to the 300?
There are also a few others using the 200, BA/Comair, Kalula etc.

[Ern DSM]

Now that you mention it I do remember seeing Kulula and BA comair using 1 or 2 of them aswell. I still think they all can do without them! Thats why SAA got rid of them, because they are old junk. Well I just hope something like this doesn't happen again because you never know what else could go wrong once an engine falls off during take-off or in mid flight.

[BRE]

quote "She said that while the plane was making a wide turn and dumping fuel, the cabin crew took the passengers through the emergency procedures, getting them to take off their shoes and practice bending down."

Why the shoes off unless they were expecting to waterland?

And does the 732 really have fuel dump devices?

[757_Driver]

shoes off in case they need to use the slides. Try jumping out of the door of an aircraft after someone has punctured the slide with their high heels.:ooh:

And does the 732 really have fuel dump devices?
nope. However this one did after the pylon fell off leaving the pipe open!:}

[Avman]

Why the shoes off unless they were expecting to waterland?

Nothing to do with a "waterland". It's essentially required to ensure that the heel of a shoe (especially a lady's high heel variety) doesn't tear up the slide should it need to be used.
However, I'm not entirely convinced that it's a good idea to escape from a wrecked (if applicable) aeroplane shoeless!

Edit: 757 driver's fingers were quicker than mine.

[Roan Delport]

Hi, where can I find some more pics off this disaster. Well done to the Captain thou. :D

[777Contrail]

SAA got rid of their B737-200's not because they were "old junk", but because the taxpayer payed for new -800's.

And they still have some operating as freighters.

The problem is maintainance. the older the machine the higher the cost to maintain it. SAA technical maintains all the BA & Kulula Boeings, but Vernon can do it cheaper himself, and it shows...............

[777Contrail]

Ruan, it wasn't a disaster.

Could have been........but stayed an incident.

[talent]

Avman asked "Why the shoes off unless they were expecting to waterland?"

So they wouldn't puncture the inflatable escape chutes I would imagine!

Better to keep your shoes on in the water because it slows down the loss of body heat but then you really should have them off before getting in the liferaft.

[talent]

Igh,
An engine detached from an Aer Lingus 737-200 about 20 years ago when it struck birds on take-off from Dublin. If I recall correct the forward fuse-pin/s or cone/s (can't recall which) failed leaving the engine slopping about held by just the cable and the rear pin or cone which didn't help as the aircraft was hard to control. Still, they landed safely.

[QCM]

757 FLYER...[As long as the aircraft is flying, there is no fire, fuel isn't peeing out at a huge rate, and everything is stabalised - i.e no further hydraulic or electrical degradation after the initial damage, then where is the urgency to get back on the ground?
Better to make sure you've run through everything, maybe also 'fly' it around a bit in a few configs and speeds to check everything else on that wing is still where it should be.]
and why not trying some touch and go?:=:E
How long this old lady will fly,can you be sure?
To land,to be sure "everything" has been done,you need: a runway,long enough,but you took off from there...gear and flaps,if possible...emergency assistance from airport...as much as possible a cabin ready for emergency ,but if you loose a wing...
This is my humble opinion,in these circumstances ,K.I.S.S. (Keep It Simple Stupid):ok:

[lomapaseo]

The pics posted elsewhere on this website (too bad we can't have just one thread) appear to show the inlet cowl separated and mostly round. This doesn't correlate with the other mount cone-bolt failure pictures.

I really don't understand the hydraulic failure condition being talked about. The loss of one engine should be reasonably accomodated in both fuel loss and hydraulic loss. Is there something else going on here?

Can somebody post a link to some better pictures?

[nugpot]

Nationwide Airlines
Press Statement
08 November 2007 – 14h30
Nationwide Airlines Salutes Pilots and Crew
Nationwide Airlines Chief Executive Officer Vernon Bricknell today complimented his entire staff and in particular the Captain and crew of Flight CE 723 for their heroic efforts in helping to maintain the company’s outstanding safety record.
Flight CE 723 was discontinued following an incident yesterday soon after take off from Cape Town International Airport.
Bricknell says this is the first major incident that the airline has experienced since taking to the skies 12 years ago.
Bricknell says he is relieved that the incident, which took place yesterday at Cape Town International Airport, did not result in injury to passengers or people on the ground.
“Upon take off of Boeing 737 Flight CE 723 yesterday at Cape Town International, the captain heard a loud noise immediately followed by a yaw of the aircraft. The captain, after confirmation of information from flight deck instrumentation that one of the engines had failed, immediately applied emergency procedures, an emergency was declared and the aircraft returned to make an emergency landing in Cape Town,” says Bricknell.
Nationwide Airlines has since determined that during the take off roll an object which is yet to be defined was ingested into the engine causing engine failure. The subsequent forces experienced by the engine supporting structure caused this to fail and for the number two engine to detach from the wing. The engine-to-wing supporting structure is designed to release the engine when extreme forces are applied to prevent any structural damage to the wing that may impair the aircraft’s ability to fly.
He reiterated the fact that the Boeing 737 aircraft is by far one of the safest aircraft in service today. “The Boeing 737 is aviation’s most successful story,” says Bricknell
According to Bricknell, there are approximately 5 000 Boeing 737 in service around the world, with one Boeing 737 taking off every 9 seconds, every day.
He says Nationwide Airlines is working with the proper authorities to establish the nature of the unidentified object and will keep the public informed as more information becomes available.
Furthermore Bricknell says Nationwide Airlines has met and surpassed local and international safety best practice standards. The airline is accredited by IOSA, the Operational Safety Audit of the International Airline Transport Association (IATA).
He says the airline industry is the most regulated sector in the world in terms of safety, training and aircraft maintenance.
‘In no other profession are skilled individuals such as pilots required to undergo testing and to demonstrate their proficiency on such a regular basis. Training encompasses a wide variety of subjects and scenarios that hopefully flight crew members will never be called upon to exercise in the operational environment. Yesterday this training paid off – the skills of the crew were called upon and procedures were carried out in a text-book fashion,” says Bricknell.
Nationwide Airlines is a privately owned airline company which flies to local, regional and international destinations.
Ends.
ACSA refused to let photographers get anywhere near the aircraft, so the pics available are not that great.

[Avman]

talent,

Avman asked nothing of the sort. I think you're getting a little confused. Pay attention at the back now!

[talent]

Avman,
My apologies - I had scrolled back looking for the original "waterlanding" post, saw your quotation from it, put two and two together and got you.
Sorry.

[lomapaseo]

I'm still trying to make sense out of this.
I picked up this link in the other thread running on this site but of course I don't have a login in order to view the referenced pictures
Some excellent close-up photos of the wing, engine mounts and the engine on AvCom ( http://avcom.co.za/phpBB2/viewtopic....=asc&start=180 )
As mentined a few posts above, EI did have a pretty massive fan failure due to birds a few years back and pretty much had only one link left on the front mount plus the cone bolt in the back holding up the engine. So in the case of massive fan damage it's the front mount links that go first. That also might explain the detached inlet cowl.
I seem to recall also that SA had a similar nasty fan failure due to birds on one of their B737-200 about the same time as the EI incident. Of course a few million hours between failures isn't a rash is it :)
Any pictures of the fan show up yet?

[lomapaseo]

nugpot


Many thanks.

Not much collateral damage arround the engine position to support a failure from the fan. Still can't resolve the front vs aft mount chicken vs. egg.

I'll wait and see what turns up tomorrow. If nothing more I suspect that's the last time we'll hear of it.

[vinayak]

hats off to the guys who flew it to safety.

[fendant]

I am admiring the flying skills of the pilots, excellent job!

On the other hand this incident strongly confirms the Airbus design philosophy for all the engine mounts. Failure proof principle is strictly applied by using sleeve/bolt design. Each of the two components can take all the design loads with the safety factors.

I don't know how Boeing convinced the FAA at that time to agree that an engine might never fall off and talk them into accepting a simple bolt connection for the 737. I do not know wether this is also true for the 777 and 747.

Frank

[JG1]

"In no other profession are skilled individuals such as pilots required to undergo testing and to demonstrate their proficiency on such a regular basis. Training encompasses a wide variety of subjects and scenarios that hopefully flight crew members will never be called upon to exercise in the operational environment. Yesterday this training paid off – the skills of the crew were called upon and procedures were carried out in a text-book fashion,” says Bricknell."


Pity you don't pay them more, Vern. 737 F/O's on less than $2k a month..tut tut

[birdlady]

You know its amazing how comments differ from forum to forum :E:E:ok::ok:

[PAXboy]

fendant I am not an aeronautical engineer but the method of securing the engine of the 737-100 + -200 changed when the -300 arrived with pylon mounted engines and all subsequent models.

There was a change by all designers to place the nacelle ahead of the wing on a pylon, rather than close coupled under it. So I think that comparison of this now obsolete design with that of any later aircraft of any manufacturer is not correct.

[NinerVictor]

Quoting from nugpot's post of the Nationwide Airlines press statement:

The engine-to-wing supporting structure is designed to release the engine when extreme forces are applied to prevent any structural damage to the wing that may impair the aircraft’s ability to fly.

Is this a standard design across Boeing types?

[757_Driver]

I think that's standard on most aircraft. If you get some damage that results in extreme vibration, its better to loose the engine than loose the wing!

[411A]

Is this a standard design across Boeing types?

Ever since the earliest design of the B707....DC-8, too.

[Nathan Parker]

Are there cases where an engine has detached solely due to an engine failure?

[lomapaseo]

Are there cases where an engine has detached solely due to an engine failure?
Yes Kalita B747, etc. etc.
The regulations do not permit a design which intentionally releases a mount under engine induced loading. However s**t happens and when it does, thankfully the aircraft designers are permitted to select a design criteria for the wing which is a tad stronger than the one they use for the engine mount. Meanwhile if an engne does happen to separate for any reason, then a continued airworthiness action under the regs (fix it) is appropriate to bring the design back into compliance (all previous events were addressed by this means).

I finally got to download some much better photos of this event showing the fan and the front mount etc.
Looks like the crap released to the news about ingestion is wrong along with the stuff about mounts being designed to fail etc.
The engine doesn't look like it fell from any significant height and it looks different in my eyes from the previous 3 events. I guess no amount of additional photos off the internet is going to satisfy me until I see a technical report. :)

[Nathan Parker]

Yes Kalita B747, etc. etc.

Thank you, I've been reading those threads.

The regulations do not permit a design which intentionally releases a mount under engine induced loading.

That's what I've been wondering. I've found FAA Part 25 regulations which say that the engine mounts must withstand sudden engine stoppages. Any other place that contains references to this?

thankfully the aircraft designers are permitted to select a design criteria for the wing which is a tad stronger than the one they use for the engine mount.

I can't find any specific Part 25 regs concerning this. Any pointers appreciated.

Meanwhile if an engne does happen to separate for any reason, then a continued airworthiness action under the regs (fix it) is appropriate to bring the design back into compliance (all previous events were addressed by this means).

And what is the fix supposed to be? Stronger mounts? If so, this suggests that the mounts weren't really serving their intended purpose, but broke away via a "loophole". Do you think it was a good thing that the Kalita engine broke away?

[IGh]

Question from NP, two slots above:

"Are there cases where an engine has detached solely due to an engine failure?"


NTSB reported on blue ice incidents in 1991. Tell-tale signature is the long blue-streak from the Fwd Lav.

-- National B727 / 30Apr74 near El Paso, RHS Engine separated at CRZ.

-- AA / 16Apr85 B727 the RHS-engine separated over Las Cruces, N.M.

-- NW / 4Jan90 over Madison, Fla., lost its RIGHT engine due to "blue-ice" from a toilet leak.

Planes landed safety after their engines fell to the ground.

The FAA, after the 1985 incident, required inspection and testing of lines and valves used to empty toilets in 727s and in January 1989 required checks of 737 lavatory systems. A "blue ice" incident occurred 12Feb90 when an Eastern Airlines Boeing 727 was forced to shut down one engine on a flight from Atlanta, Ga., to Sarasota, Fla.

The LHS engine of MD8 aircraft have ingested blue-ice from its FwdLav at CRZ, ??? but engines stay with the DAC-aircraft (??found no separation??).

[Nathan Parker]

NTSB reported on blue ice incidents in 1991. Tell-tale signature is the long blue-streak from the Fwd Lav.

Thank you sir. Is it generally agreed that the engines falling off preserved the structural integrity of these airplanes?

[IGh]

"... Is it generally agreed that the engines falling off preserved the structural integrity of these airplanes?"

The best summary of the varying design concepts is found in the early 1990's -- some of the reporting may be available on the "web". The _Seattle Times_ had some excellent reviews of the competing design concepts -- Boeing's vs Airbus'.

Engine -Pylon Fuse Pins (break points) WERE relative to earlier Boeing design concepts. Airbus used an alternative concept. Recall the post accident research in the wake of “El Al 1862” B747-200F / 4Oct92 (#3 Eng gyroscopic- separation and then speared #4 Eng). This B747 failure sequence had happened earlier aboard China Air B747F / 29Dec91; same sequence suffered by two B707s on 31Mar92, & 25Apr92.

After the engine separations of the early ‘90’s, there was much study of the two contrasting concepts. Here’s the _Seattle Times_, Jan 9 ’93, pg A9, headline

“AIRBUS AVOIDED USE OF ILL-FATED FUSE PINS / ENGINES DESIGNED TO STAY ATTACHED TO JETS’ WINGS DURING EMERGENCIES”, quote from the story by Achohido:

= = = \/ = = = EXCERPT = = = \/ = = =

“Airbus Industrie … does not use breakaway safety bolts, called fuse pins, to mount jet engines to the wings … Instead, when Airbus engineers began designing jetliners for the first time in the early 1970’s, they ruled out fuse pins in favor of permanently attaching the engines and its supporting structure, called a strut, to the wing.

“’We have no fuse pins,’ said a high-ranking Airbus engineer. ‘In other words, we have designed it so that … will stay attached to the wings in all circumstances.’

“That difference points up a potential hazard posed by fuse pins used on jetliners built by The Boeing Company.

“Designed to snap and release an engine … fuse pins used on more than 930 Boeing 747 jumbo jets … susceptible to corrosion and cracking … used on more than 480 757 twinjets can develop fatigue cracks….

“’… rules require the fuel tanks … and wing to remain intact to avoid the risk of fire,’ said the Airbus engineer. ‘The Boeing and Douglas approach is that, in the event of a survivable belly landing, the engine would come off the wing, hopefully cleanly. Our approach is that the engine would stay on the wing and slide along, again leaving the fuel tanks intact and providing a degree of protection for the fuselage.’

“… FAA spokesman, said the divergent Boeing-Airbus philosophies both meet the existing safety rules….

“… In the late 1970’s, Boeing considered and then ruled out using the Airbus design …”

= = = /\ = = =END excerpt = = = /\ = = =

_Seattle Times_ offered very good illustrated descriptions of the Cone Bolts and Fuse Pin failures (B707, B747, B737 cases): see last week of Dec'92 of the _Seattle Times_, and then during Jan'93 [eg, 9Jan93, pg A9 excerpt above].

_Air Line Pilot_, Aug'93, pg 38: Jan Steenblik did a good story on modifications to the B747 Engine Struts. [similar stories in press of 18Jun'93].

_AW&ST_, 1Nov'93, pg 39-40, "Boeing ... is completing the design of a 747 strut modification that relies on reinforced pylon-to-wing attachment to preclude engine separation in flight. This abandons the clean separation design faulted in Wolleswinkel's [AAIB-Holland] preliminary report...."

Hmmm -- well, after the B737-200 case, maybe the "clean separation design" is still applicable to some Boeing Airliners?

Maybe some hardworking reporter will provide us a review of newer designs of Engine Mounts for B777 and 787.

[lomapaseo]

Quote:
Originally Posted by lomapaseo
Yes Kalita B747, etc. etc.
Thank you, I've been reading those threads.
Quote:
The regulations do not permit a design which intentionally releases a mount under engine induced loading.
[quote]
That's what I've been wondering. I've found FAA Part 25 regulations which say that the engine mounts must withstand sudden engine stoppages. Any other place that contains references to this?
Only in part 33 which say that specific levels of failure (blade loss test, large bird test) must not result in distress to the engine side of the mounts (of course for other far worse failure conditions you just might get some distress, although quite rare) see again Kalita, blue ice events, etc.
Quote:
thankfully the aircraft designers are permitted to select a design criteria for the wing which is a tad stronger than the one they use for the engine mount.
I can't find any specific Part 25 regs concerning this. Any pointers appreciated.
I believe that it is under wing gust load section etc. requiring that the critical wing structure meet 150% of the worst loads described under the part 33 engine blade loss test. So it's relatively easy to set some minor part like the pylon tmount etc. to break before the wing etc. etc. Lots more could be said but in the interests of brevity I follow the KISS principal
Quote:
Meanwhile if an engne does happen to separate for any reason, then a continued airworthiness action under the regs (fix it) is appropriate to bring the design back into compliance (all previous events were addressed by this means).

And what is the fix supposed to be? Stronger mounts? If so, this suggests that the mounts weren't really serving their intended purpose, but broke away via a "loophole". Do you think it was a good thing that the Kalita engine broke away?
Under continued airworthiness any fix can be employed that address the consequences or the cause of a failure condition, either general or specific. If the product does not comply with a specfic regulation under part 33 or part 25 then it's a good idea to at least have a closing action available for that item. In the meantime even restricting the environment it operates within or adding onerous maintainence requirements could be a temporary (for years) solution.
The Kalita event photos seem to show the rear mount was pretty much intact but the engine itself missing. That leaves it doubtful that the mount was overloaded but instead the engine broke away from the mount for other reasons. I believe that the corrective action addressing this did not include the mounts
And finally the suggestion that an interim corrective action for the Nationwide failure should be a grounding of the local fleets based on a loss in confidence of their airworthiness is quite surprising on its surface. the specific failure being discussed is still under investigation and in itself is a benign failure condition to the aircraft and its operation by virtue of both design analysis under the FARs as well as the historical outcomes within a quite extensive millions and millions of hours data bank.
On the other hand if there is strong reason to suspect that a sub population of conditions exist in a very small fleet than the issue is more operator related than design related.

one might suspect that I am still smiting over the localized action of the Danish authorities about the Q400 ) but lets not go there :)

[nugpot]

And finally the suggestion that an interim corrective action for the Nationwide failure should be a grounding of the local fleets based on a loss in confidence of their airworthiness is quite surprising on its surface.
Do you know that that is exactly what they have done.
Read Emergency AD from SA-CAA

[fly nice]

I am told the JT8D weighs 4 tonnes with cowlings and accessory gearbox, etc. That, along with the drag of a seized engine, make it a useful though unintentional jettison. Notwithstanding, it remains undisirable.
Any clever boys and girls got some ideas on the pro's of a 4 tonne instant jettison with gear stuck down (A hyd lost) vs a retracted gear, engine seizure scenario?
This aircraft is (thankfully not WAS) ex LH with smaller -15A engines. Sea level. Max pax with approx 10 tonnes fuel. Looks rainy (cool day), so assume max TO thrust. Bear in mind that with the engine (seized) remaining on scenario, the drag of the gear is still a factor in initial climbout until retracted.

Calling all mathematicians and aeronautical engineers:8

Impressive flying display, in anyones eyes, well done:D.

[fly nice]

The assumption for now seems to be that a seizure could have accounted for the separation...:ouch:

[lomapaseo]

The assumption for now seems to be that the transverse gyroscopic forces of a catastrophic seizure could have accounted for the separation...

I beg your pardon:confused:

I've never heard of such a force description in all my school years.

[wileydog3]

I drove the -200 for a number of years and it was routine to have a reverser open on the 6th month checks. It took a lot of rudder until you got the engine shut down, a bit more so than just an engine failure, of course.

A few things added to the drill. 1) if you had your hands in the wrong place when the reverser opened, you got a good shot as the throttle slammed to idle. Not fun. 2) the event was usually introduced shortly after getting airborne and V2 engine problems require much better footwork on the rudder than a simple V1 failure. 3) after shutting down the engine it was pretty much just another single engine approach except slightly higher power settings due to the drag.

At 'my house' a friend of mine had an engine separate coming out of PHL just after takeoff. No problem. Again, just another single engine approach.

The little -200 would trim up very nicely for such an approach and the only problem was not trying to hold the airplane off for a smooth touchdown as with flaps 15, it would float forever.

FWIW, the 727 also tossed a few engines. The bolts holding the engine on the pylon are not that thick and are designed to fail with a 'catastrophic seizure' as some others have noted. Better to have the engine leave the airplane than have the gyroscopic forces tear up fuselage or wing (in the 737s case).

[alexmcfire]

Depends where the B727 engine lands, central engine isn´t too pleasant if it fall on another engine.

[Nathan Parker]

The best summary of the varying design concepts is found in the early 1990's -- some of the reporting may be available on the "web". The _Seattle Times_ had some excellent reviews of the competing design concepts -- Boeing's vs Airbus'.

Thanks, I'll look for it.

[Nathan Parker]

Only in part 33 which say that specific levels of failure.....

Thanks, I'll look these up.

[TwinJock]

Flight CE 723 was discontinued following an incident yesterday soon after take off from Cape Town International Airport.

What a joke - the flight was discontinued - a nice way of saying that their was no way that the crew could continue to Johannesburg, even though I wanted them to!!!


Bricknell says this is the first major incident that the airline has experienced since taking to the skies 12 years ago.

I seem to remember a BAC 111 losing an engine from JNB to GRJ, and the crew electing to continue to GRJ on one engine!!! No press to give Vernie a hard time then and he got away with it!! A picture of a missing toilet servicing cap does not make for good reading - not enough blood and guts, oops, sorry, just blood!!:ok:

He (Vernon) says the airline industry is the most regulated sector in the world in terms of safety, training and aircraft maintenance.

Yea, maybe in the rest of the world, but definitely not in SA and the rest of Africa!!

[rickety]

I'd be interested in the opinions of the professionals here about an article from Independent Online in SA. It seems well written without the normal sensationalisms that are often (rightly) castigated here.

http://www.int.iol.co.za/index.php?set_id=1&click_id=13&art_id=vn20071110093801406C807260

[Blues&twos]

This bit is great:

But that's not what happened, according to the source who examined the damaged wing on Thursday.

"I'm not a structural engineer, but I examined the damaged wing up close and it was very clear that one of the pylon's struts - about the thickness of your arm - had sheared clean through, as if cleft with an axe," said the source.

"It appears as if once the strut had sheared, it tore the right-hand side bolt clean out of the wing, then the whole engine detached itself.

"The strut that sheared was the one closest to the fuselage.

"I don't know if there was a latent crack there or something (else) that had not been picked up during inspection."


Right.:ugh:

[lomapaseo]

I'd be interested in the opinions of the professionals here about an article from Independent Online in SA. It seems well written without the normal sensationalisms that are often (rightly) castigated here.

http://www.int.iol.co.za/index.php?s...3801406C807260

Well the attached article adds nothing but amateur postulations

From the clear pictures I have seen of the engine fan there is no significant damage.

Engineers do not know what loads will break the mount, they only know that at a prescribed load level it won't break (there is a difference)

I'm not a fan of concentrating on the obvious damage to a dual mount link and ascribing it as primary with a wave of the typewriter as fatigue. It is entirely possible it is secondary to the other side as primary.

So what did happen on the other side??

Yes the design is relatively failsafe as it protects the wing box while allowing the engine to fall away resulting in less thrust, less drag and a redundant hydraulic system left to fly the aircraft

[Nathan Parker]

Here's a link to an article that IGh mentioned:


http://archives.seattletimes.nwsource.com/cgi-bin/texis.cgi/web/vortex/display?slug=1679083&date=19930109

[lomapaseo]

http://archives.seattletimes.nwsource.com/cgi-bin/texis.cgi/web/vortex/display?slug=1679083&date=19930109

"We have no fuse pins," said a high-ranking Airbus engineer. "In other words, we have designed it so that (the engine and strut) will stay attached to the wings in all circumstances."
A very misleading article
Airbus only knows what has happened so far not that they can stay attached in all circumstances including in the air due to any engine failure.
How well did they survive in Quito A340? How well did they stay attached on The A300 in AA587?
How well will they survive with about 5 fan blades missing?
The FAA spokesman said it correctly both Boeing and Airbus mounts are "safe enough" else they wouldn't both be flying today.
It's best not to claim "not me" in the midst of public agony about the other guy.
I'll admit that the degree of redundant load paths could be different, but in the case of the B747 experience, cited in the article, indeterminate multiple load paths are not desireable or easy to fix when you can't simply figure out what will break it in the first place.
So what makes all this public discussion to get Byron Acohido and his typewriter energized? Does he really have an end point? Does he feel that the recent B737 was another disaster in the making like his rudder teatise?

[FinalVectors]

More pics of the aircraft and engine.
It's a Norwegian forum...so just scroll down to find the pics.

http://www.flightsim.no/ubbthreads/ubbthreads.php?ubb=showflat&Number=373169#Post373169

[antic81]

According to the African forum the SACAA have issued an AD grounding all 737-200's in South Africa, pending examination.I believe that NW operate 12 of them.
That's going to hurt.

[fendant]

Sr. Lomapaseo,

I do not think that the article is misleading at all. There are just 2 different design concepts for taking care of the longitudinal and transversal loads during normal operation:

Boeing accepts that an engine might leave the wing with no redundancy if an attachment bolt fails. They claim that they designed it in a way that it does not damage the fuel tanks inside the wing during separation. The pictures on the Norwegian website show that the concept worked. The flip side is that they rely on competent maintenance teams to check in short intervals regularly the bolts and replace them with (costly) genuine OEM parts, if they detect any flaws.

Airbus on the other hand makes it under all circumstances a permanent attachment by designing redundancy in.

Both concepts are approved by the authorities on both sides of the pond, so there is not a good and a bad one, also proven by millions of incident free flights.

Your hint at the Iberia Quito incident is misleading indeed. It prooves that the Airbus concept can withstand also design loads outside of the operating enveloppe. Please note that both engines are still on wing, although at some strange unpreferred angles.

Comparing both design concepts I personally do not want to leave especially Quito in a 777 dumping one engine on the runway.

Frank

[SOON2B]

Would an entry of "right engine missing" be appropriate for maintenance in this case or something more elaborate like "suspect bolts and nuts not adhering to aircraft skin anymore"?:rolleyes:

[lomapaseo]

Sr. Lomapaseo,
I do not think that the article is misleading at all. There are just 2 different design concepts for taking care of the longitudinal and transversal loads during normal operation:
Boeing accepts that an engine might leave the wing with no redundancy if an attachment bolt fails. They claim that they designed it in a way that it does not damage the fuel tanks inside the wing during separation. The pictures on the Norwegian website show that the concept worked. The flip side is that they rely on competent maintenance teams to check in short intervals regularly the bolts and replace them with (costly) genuine OEM parts, if they detect any flaws.
Airbus on the other hand makes it under all circumstances a permanent attachment by designing redundancy in.
Both concepts are approved by the authorities on both sides of the pond, so there is not a good and a bad one, also proven by millions of incident free flights.
Your hint at the Iberia Quito incident is misleading indeed. It prooves that the Airbus concept can withstand also design loads outside of the operating enveloppe. Please note that both engines are still on wing, although at some strange unpreferred angles.
Comparing both design concepts I personally do not want to leave especially Quito in a 777 dumping one engine on the runway.
Frank
Well we probably have more where we agree than a difference. I'm not sure that I have any reason to change my statements, even though I agree with much of which you have said.
My major point had to do with this side of the discussion
Airbus on the other hand makes it under all circumstances a permanent attachment by designing redundancy in.
Either design, Boeing or Airbus will lose its permancy in an abnormal situation not specified in the regs. We agree that both meet the regs. Nobody so far has demonstrated that their design tollerance can meet something over and above the regulation. Claims are just that only unvalidated claims based on assumptions.
And I am not a supporter of redundancy in an engine mount when you break a wing box and still have retained the engine in an abnormality.

[Taneat]

Well the Engineers hate Pilots making the diagnosis so you'd have to just give the symptoms:
"Moderate right yaw observed shortly after takeoff. On subsequent walkaround, F/O noted more headroom than usual whilst checking right wing underside"

Great effort guys.

[ironbutt57]

aft cone bolt old news happened before

[MD11Engineer]

It is easy to damage to cone bolts during installation if the engine change team is not carefull. During my apprenticeship many years ago I had to take part in an engine change of a 737-200. The problem was that there were 5 engineers, who each thought that they were in charge and gave conflicting orders to pull the engine hoists. The result was that a front cone bolt was not aligned properly into it's hole in the vibration damper and got exposed to strong side forces it was not designed to hold (at the undercut below the threaded portion) when the hoists were pulled. After the incident was discovered one stupid engineer just wanted to push it into the right position and continue with the installation. Fortunately the others were brighter and insisted on removing the cone bolts and getting them and the vibration dampers NDT'd. the result was that the affected cone bolt had a hairline crack at it's weakest point.
It is quite possible that other airlines might just swipe an incident like this under the table, leading eventually to an engine seperation in flight.

BTW, on a 737-200, on physically loosing #2 engine you are loosing "A" system hydraulic fluid, #2 generator, R/H pneumatics and fuel from the torn fuel line.
Doing the normal fire drill (throttles to idle, start lever to off, pull fire handle) will close the fuel spar valve and the R/H "A" system hydraulics supply fire shut off valve in the #2 engine driven pump supply line. If done fast enough, the loss of hydraulic fluid will be limited and "A" system will still receive pressure from #1 engine driven pump (It is a long time ago, but IIRC there are some check valves in the "A" system hydraulics module, which would prevent further loss of fluid from the torn pressure line and also the #2 EDP case drain line has IIRC a check valve, I would have to look it up in my old course notes.
"B" system on the 737 jurassic is driven by the EMPD's and would continue to be operational.

[yachtno1]

I think those "check valves" are called hydraulic fuses ...:)

[Feline]

From the Johannesburg Star Newspaper this morning:

"The Civil Aviation Authority grounded all Nationwide aircraft on Thursday night.

Nationwide spokesperson Charmaine Thomé said on Friday morning that the CAA had withdrawn the airline's Aviation Maintenance Organisation licence.

"We've suspended our normal operations because they've suspended our licence," said Thomé.

"Currently we are as confused as you are.

"The reason for it - we have no idea."

She said the licence was suspended on Thursday night and the first flight affected was Friday morning's 6.50am departure from Johannesburg to Cape Town.

Thomé said Nationwide CEO Vernon Bricknell was meeting with the CAA and she could not comment further.

The CAA was not immediately available for comment and, in a written statement, referred only to "a decision of public importance regarding the non-compliance of an airline operating in South Africa".

The CAA is the oversight authority for the aviation industry and deals with aviation safety and security.

By early Friday morning, all Nationwide flights listed on the Airports Company SA website for the day were either listed as cancelled or indefinitely delayed. At least 26 Nationwide flights due to leave from Johannesburg, Cape Town and Durban were affected.