Incident: Baltic BCS3 near Bordeaux on Feb 12th 2020, uncontained engine failure

The Aviation Herald		Last Update: Friday, Mar 14th 2025 18:29Z 31411 Articles available Events from Mar 23rd 1994 to Mar 13th 2025
www.avherald.com	Incidents and News in Aviation

List by:

Filter:

Incident: Baltic BCS3 near Bordeaux on Feb 12th 2020, uncontained engine failure

By Simon Hradecky, created Wednesday, Feb 12th 2020 17:34Z, last updated Wednesday, May 4th 2022 19:19Z

An Air Baltic Bombardier C-Series CS-300, registration YL-AAU performing flight BT-677 from Riga (Latvia) to Malaga,SP (Spain), was enroute at FL390 about 80nm south of Bordeaux (France) when the left hand engine (PW1500G) suffered an uncontained failure and was shut down. The crew diverted the aircraft to Bordeaux where the aircraft landed safely on runway 23 about 25 minutes after leaving FL390.

The airline reported the captain shut the left hand engine down and diverted to Bordeaux. A replacement aircraft is dispatched to take the passengers to Malaga.

A replacement CS-300 registration YL-AAV was dispatched to Bordeaux and resumed the flight. The aircraft is curently enroute at FL290 and is estimated to reach Malage with a delay of 8 hours.

The French BEA reported the left hand engine suffered a technical failure, the aircraft diverted to Bordeaux. The occurence was rated a serious incident and has been delegated to the US NTSB, who are already investigating three occurrences of the same type that Swiss had suffered in 2019, see Incident: Swiss BCS3 near Paris on Jul 25th 2019, engine shut down in flight, Incident: Swiss BCS3 near Geneva on Sep 16th 2019, uncontained engine failure and Incident: Swiss BCS3 near Paris on Oct 15th 2019, engine shut down in flight.

In all three cases of Swiss the affected engine had suffered the uncontained release of the stage 1 low pressure compressor rotor.

As result of the occurrences in 2019 the FAA had released Air Worthiness Directive 2019-19-11 and Transport Canada had released Emergency Airworthiness Directive (EAD) CF-2019-37, the latter limiting the N1 setting to 94% above FL290, which requires the autothrust to be disengaged in order to respect that limit.

According to Mode-S Data transmitted by the aircraft the aircraft had been enroute for about 4 hours and had done several climbing and descending changes in flight levels. Near Bordeaux the aircraft had been enroute at FL370 then climbed to FL390 and had been level at FL390 for about 2 minutes when the engine failure occurred.

On Mar 31st 2020 the FAA released another Airworthiness Directive AD-2020-07-02 arguing:

The FAA has received reports of four instances of IFSDs occurring on the affected model turbofan engines since 2019.

In response to the two IFSDs that occurred in July and September 2019, and in response to ongoing investigations of these IFSDs, the FAA issued AD 2019-19-11 (84 FR 50719, September 26, 2019), to perform inspections of the LPC R1 to prevent failures. The FAA subsequently superseded AD 2019-19-11, issuing AD 2019-21-11 (84 FR 57813, October 29, 2019) in response to another IFSD and to expand the population of affected engines that needed inspection of the LPC R1. Since the effective date of AD 2019-21-11, another IFSD occurred in February 2020. Analysis by the manufacturer determined that the LPC vane schedules were putting the engine in a condition to experience an acoustic resonance that damages the LPC R1, which then leads to LPC R1 failure. In response, the manufacturer updated the EEC FADEC software to improve vane scheduling to avoid acoustic resonance.

This condition, if not addressed, could result in uncontained release of the LPC R1, damage to the engine, and damage to the airplane. The FAA is issuing this AD to address the unsafe condition on these products.

On May 4th 2022 the NTSB released their final report concluding the probable causes of the incident were:

A No. 1 (left) engine low pressure compressor (LPC) stage 1 integrally bladed rotor (IBR) separation due to a high cycle fatigue crack (HCF) that originated at the runout of an airfoil leading edge root radius. The HCF crack developed because of a mechanically coupled LPC stage 3 and stage 1 IBR mode excitation and blade flutter response. The excitation was driven by an acoustic tone generated by turbulent airflow passing over the 2.5 bleed valve duct cavity while the engine was operating at high speeds in specific flight conditions. A primary contributor to the failure mode was an electronic engine control (EEC) software update that changed the LPC vane schedule and increased the likelihood of LPC stage 1 IBR blade flutter onset within the engine operating range.

The NTSB analysed:

The No. 1 engine low pressure compressor (LPC) stage 1 integrally bladed rotor (IBR) failure was caused by a stage 1 IBR high cycle fatigue crack that originated at the runout of an airfoil leading edge root radius. Multiple analytical methods, including two-dimensional (2D) computational fluid dynamics (CFD), acoustic testing, and instrumented flight testing identified a coupled LPC stage 3 and stage 1 IBR instability caused by an acoustic coincidence with the 2.5 bleed valve duct cavity. At high engine N1 speeds, the stage 3 IBR blade tips generate vortices/turbulent airflow and given the right conditions, the turbulent airflow can create an acoustic tone as it passes over the 2.5 bleed valve duct cavity, located immediately aft of the LPC stage 3 IBR (Figure 1). The acoustic tone drove a LPC stage 3 IBR blade 1st bending mode excitation that was then mechanically transferred through the LPC module and excited a LPC stage 1 IBR stiffwise bending mode that was present at the same approximate frequency. The resultant stresses on the LPC stage 1 IBR blades exceeded material limits and subsequently led to crack formation and eventual progression to overload failure.

Factors that contributed to the LPC stage 3 and stage 1 IBR acoustic coincidence and blade excitation within the engine operating range were: installation of electronic engine control (EEC) Software V2.11.7.2 and the low time rub in period on the LPC IBR blade tip clearances.

EEC Software V2.11.7.2 changed the LPC inlet guide vane schedule to rotate the IGV�s in the closed direction at specific high power engine conditions to improve engine stall/surge margin. The revised vane schedule inadvertently created conditions that were favorable for generation of the 2.5 bleed valve duct cavity acoustic tone and IBR mode excitation.

New engines have tighter clearances between the LPC IBR blade tips and the outer air seals. The reduced clearance created unsteady loading at the blade tip region and resulted in stronger acoustic coupling/flutter response. After a rub in period, the clearance increases, and the occurrence of flutter onset is reduced.

There were three PW1524G-3 and one PW1521G-3 LPC stage 1 IBR separation events between July 25, 2019 and February 12, 2020 that occurred on multiple operators. The incident detailed in this investigation was the fourth PW1500G series LPC stage 1 IBR failure. The engine parameters at the time of each of the events and the resulting engine damage were consistent. Additional information about the failure mode and investigation process are available in the investigation dockets for the first two incidents, NTSB investigation numbers ENG19IA029 and ENG19IA034.

The engine (Photo: Aerotelegraph):

Reader Comments: (the comments posted below do not reflect the view of The Aviation Herald but represent the view of the various posters)

A220-300
By free2go on Tuesday, Feb 18th 2020 16:50Z

So now is a question from ordinary passenger. How safe can I feel when on board A220-300 with this tricky engines?

Contained failure?
By Arcanus on Monday, Feb 17th 2020 02:59Z

Contained or not, what the picture is showing is a catastrophic structural damage, apparently at the intake of the engine compressor.
The correct definition of it is irrelevant.

Gerry
By Jetman on Sunday, Feb 16th 2020 19:53Z

Of course, casing ie, as I specified for the fan blade containment, is hopefully designed to contain fan blade liberation as Looking at the fan cowling structure, won't do that much...
I guess the parts you mention in low mode fracture probability are what is called LLP for which OEM have to demonstrate following test, analysis and in service data that the part referenced (ATA chapter 05) have a predictable design life to sustain or support all combination of load during operation...because if they fail they can not be contained and be a potential hazard to A/C safety... the best example is DC10 in Sioux city.

Jetman
By Gerry on Sunday, Feb 16th 2020 15:41Z

Jetman, just a minor tweak to your comments on containment. The various engine certification regs required the engine casings to be able to contain the release of a single compressor or turbin blade. (Engine casings rather than nacelle). For failure of elements of a shaft system (shaft or disc) it must be demonstrated that they are extremely remote. (Extremely remote is less than 1 chance in 10 million flying hours).

@Mech
By Jetman on Sunday, Feb 16th 2020 12:21Z

You are bringing an interesting point as per official definition an event is categorized as uncontained if the debris following blade rupture or non life limited categorized part are not contained by the nacelle..
However, OEM containment certification test for the fan , it must demonstrate if liberated, to be contained by the casing..bear in mind that only loose rotating blade must be contained, disk and spool can not and are therefore life limited by design, and looking at the fan cowl design....
Looking at the picture we see damage on OGV'S and fractured open
LPC casing, which means as OGV are static parts, something from inside was liberated in a circumferential motion , which IMHO make sense of a uncontained event but would be interesting to see fan cowl picture.

Free speech
By (anonymous) on Sunday, Feb 16th 2020 05:56Z

I have also had jetman pounce on me and didn't too much care for his demeanor and really the way he " engaged " me but where I come from we believe in the right to free speech so not sure where you hail from but if you don't like what he retorts with then you have to right not to " engage ". Just go do something else.

Ecumenico
By Jetman on Saturday, Feb 15th 2020 22:23Z

I am just correcting your comments, which is not persecution just education, ie....
'' It requires that the low pressure turbine shaft runs at much higher speed''
The advantage to increase turbine speed is to increase its power then to reduce the number of stages...
'' GTF is a great idea, a great innovative concept''
Yop , flying for the last 50 years but with development fiasco like superfan in the late 80's....
At least, your baloney comment brings answers to other readers, and seriously hard to believe that last 2 Ecu post are from same person....I am not the only one to let this site and this industry to be degraded by such foolishness.

@ Jetman
By Ecumenico on Saturday, Feb 15th 2020 20:15Z

Jetman Why do you keep trying to engage me in this fruitless discussion? I do not want to annoy the participants responding to your derogatory terms, I am tired of your constant persecution.
You do not not even take the time to analyze my words.

I never said that the concept of GFT is bad. It requires that the low pressure turbine shaft runs at much higher speed, being reduced via the central planetary gear box, before connecting to the fan, which will run more efficiently at a lower speed. You are saying the same, so we and 320 Captain are in accord. GTF is a great idea, a great innovative concept, but too many new factors were insufficiently calculated or the resistance of materials were incorrectly assumed.

The Engine Pressure Ratio, defines the efficiency of the engine with an unavoidable increase in the turbine temperature as the EPR increases. Don't tell me that you didn't know that.

Ecumenico con't
By jetman on Saturday, Feb 15th 2020 18:51Z

Last, combustor temp is not depending of the air dilution ratio but more of the HPC ratio and fuel added accordingly.
You are mistaking the dilution rate 12/1 with HPC which have simply double on new engine generation , above 40/1, to simply meet the fuel efficiency requirement..

I think you may definitely follow advise of captain 220...

Ecumenico again
By Jetman on Saturday, Feb 15th 2020 18:39Z

Wrong again on basic engineering concept......
''Optimum RPM leading to optimum speed''
Of course and captain 220 is fully right, fan is more efficient at lower speed and turbine at higher speed...
This is the advantage of this concept as the Fan and turbine not linked together and rotate then at their optimum speed.
'' The fast turning low pressure turbine shaft, is in my view, at the origin of the shaft bowing''
Bow rotor is not a question of speed but but thermal deformation during engine cool down due thermal cooling asymmetrie of the part and material.
It is not new, Concorde had a procedure for bow rotor, trent, GE90 and recent engine such as ie, Leap, which have Fadec protection during (longer) start for bow rotor detection (vibration)..

@ A220 Captain
By Ecumenico on Saturday, Feb 15th 2020 15:29Z

Your comment is vary vague and is repeating the advertising of the Pure Power GTF engine. Optimum RPM leading to optimum speed.

Take your time and investigate How the higher efficiency of an engine is directly related to the increase of the Engine Pressure Ratio, which invariable determines a higher turbine temperature.

Read again my comment about the not so robust design of the low pressure turbine shaft responsible for the structural failures and also about the poor lubrication responsible for the presence of metal chips in the oil filter. There is also a suspicion of abrupt aerodynamic forces at the entrance of the compressor leading to the uncontained recent failures.

You are so adamantly infatuated with yourself and evidently you are not an engineer, how do you dare to call me a moron?

It's not the engine's fault
By Sierrakiller on Saturday, Feb 15th 2020 09:24Z

Anybody here to see the obvious? It's not the engine's fault. It's the airspace. All engine failures of LX and BT appeared to happen in french Airspace. ;-)
And the other main topic of all this:
It is our lovely globalisation, why we know all about this.
In the older days there where also tons of aircraft/ engine failures all over the world. But nobody noticed about due to the fact that the world was not connected as it is nowadays.
Can you imagine that even in the 1940s they invented new materials and parts which failed?
So what?
Where mankind works, there will happen mistakes and failures.
That's human factor!
And all of the inventors are working hard on it to improve. (I hope! ;-) )
Nice days to all!

Uncontained?
By Mech... on Saturday, Feb 15th 2020 08:15Z

i find I curious but I might be misinformed...
in my view an engine non containment is where parts of the engine exit through the outer cowlings which are constructed in a way to keep any engine failure from damaging the fuselage or wing. Parts falling out the back end I think is not a uncontained failure (any HPT Failure ejects its blades out the back )
So if the Cowls are in tact... why are we calling it an uncontained failure???

Ecumenico is a complete moron
By A220 Captain on Saturday, Feb 15th 2020 06:56Z

Ecumenico, bypass ratio has no direct relationship to turbine temp or RPM or lubrication. Higher temps ARE directly related to higher fuel efficiency. The relatively high rpm of the low pressure turbine allows that part to spin at an optimum rpm, while the gearbox allows the fan to spin at its optimum speed.

The engine is a fabulous design, quiet, fuel efficient, and strikingly beautiful from the rear quarter. To the extent it inspires me to brush up on my OEI procedures...well, that just makes me a better pilot doesn�t it?

I�m sure P&W will get the issues ironed out soon.

In the meantime, I recommend you stay off any and all aircraft, as well as this website.

Have a nice life.

@ Bob Lackey
By Ecumenico on Friday, Feb 14th 2020 19:46Z

I agree with your analysis Bob. The fast turning low pressure turbine shaft, is in my view, at the origin of the shaft bowing, failure of blades, seals, vibrations and metal chips. Apparently not enough robustness of shaft, blades and poor lubrication.

The combustion chamber liners are exposed to much higher temperatures at an Engine Pressure Ratio of 12 to 1. Redesign, has not solved their failure. Material limit reached?

Whatever engine resulting form the multiple fixes, would carry a ballast of too many improvised patches, not included in the original design, that would degrade the expected performance.

Maybe a complete new design, incorporating those corrections and the new atmospheric conditions, will materialize the promised Pure Power of this innovative idea.

Robert
By Jetman on Friday, Feb 14th 2020 08:01Z

Engines have warranty for a period of time/hrs from new whichever comes first like your car, but also as negotiated when bought, cost maintenance in operation based on reliability that involve not only failure but also performance deterioration.
Nowadays and most probably in this case and not to go in detail, engines are now sold with per per hour utilisation program coverage, meaning you pay the manufacturer a fee per hour utilisation for total care....each manufacturer have their dedicated acronym for such program, look on the web.
More over and in this case, if the failure is traced to be manufacture issue, the cost for repair will be supported by the OEM with also, maintenance, operation disruption and lease spare engine coverage..

GTF
By Bob Lackey on Thursday, Feb 13th 2020 23:50Z

Pratt and Whitney has spent billions of dollars replacing GTF engines. Bowing which caused slow start times, failure of the number 3 bearing seal causing metal chip detection alarm, knife edge seal redesign causing vibration, new software drop that unexpectedly caused vibration, auxiliary gearbox causing vibration and combustion chamber liners wearing out too fast. The combustion chamber liner has been redesigned several times with disappointing results. Of particular concern are the aluminum titanium blades in the LPT proving to not be robust enough. They crack and break causing engine failure including parts falling with a failure in a Swiss A220.

Pratt is working overtime to replace all these engines with engines with redesigned and upgraded parts. The main gearbox which was the big worry initially is holding up very well.

Just wondering
By Roberts on Thursday, Feb 13th 2020 20:40Z

Who is covering cost of an engine replacement in such a high rate as this is pretty expensive? Is it Airline/ Manufacturer/Engine manufacturer/Somebody else?

@EASA AD
By SJS B2 on Thursday, Feb 13th 2020 13:36Z

The FAA AD 2019-19-11 have been supersede by FAA AD 2019-21-11. As for the EASA AD, they did issue an AD, US-2019-19-11 on 26-Sept 2019. They have also issued FAA AD 2019-21-11 under the EASA AD US-2019-21-11. The FAA AD is issued due to state of design for the engine, not state of design for the airframe.

Re: EASA AD
By RustyToad on Thursday, Feb 13th 2020 11:42Z

From the UK CAA website, typical for other national authorities:

"Aircraft on the UK Register are required to comply with applicable UK ADs, European Aviation Safety Agency (EASA) ADs and those issued by the National Authority of the State of Design."

Since Canada is the National Authority, the TC EAD would apply to all aircraft being operated.

The existance of the FAA AD makes sense as it was issued a month before the TC one.

EASA?
By (anonymous) on Thursday, Feb 13th 2020 11:32Z

still no AD from EASA? Interesting...

@dead links
By LF on Thursday, Feb 13th 2020 10:11Z

Fixed

@dead links
By LF on Thursday, Feb 13th 2020 10:10Z

The links don't seem to be properly formed. If you take the URL that you can see at the top of the browser and replace the value after "article=" with the code in the malformed link, it will work. It would probably be quicker to just search for "BCS3".

@ fsxdriver on Thursday, Feb 13th 2020 08:51Z
By Simon Hradecky on Thursday, Feb 13th 2020 09:53Z

Check again, please, I just fixed them.

dead links?
By fsxdriver on Thursday, Feb 13th 2020 08:51Z

The links to the swiss incidents don't work for me, they just 404, anyone else got the same problem?

@bt crew
By Alex Hertz on Thursday, Feb 13th 2020 08:20Z

The 300cycles is something dreamed up by swiss and PW. There is no evidance it is a magic cut off time point.

Knowing the cycles on this incident would be very interesting and if they have the same software or engine rating as swiss

By enginechanger on Thursday, Feb 13th 2020 08:10Z

Engine change does not mean that the engine has failed. 100 engine changes but not 100 engine failures.

Engine changes
By BT Crew on Thursday, Feb 13th 2020 06:59Z

Yes we�ve changed countless engines due to certain components wearing faster than they should, but since when is replacing it before if fails a failure (Other than for PW that obviously coldn�t deliver what they promise)??

This thing is related to engines with less than 300 cycles hence only the aircrafts with an effected engine is limited to FL290 atm

Junk
By Red baron on Thursday, Feb 13th 2020 06:48Z

This piece of junk makes the SSJ look good. Really.

By Alex Hertz on Thursday, Feb 13th 2020 05:34Z

1 more failure on unreliable engine, I remember comment from "experts"it is amazing brilliant tip top.

This aircraft type can not go to 2 days without being AOG. Air baltic used to have engineer on board first 10 flights and only operate Riga zurich on new aircraft, why? Because when Aog in zurich swiss airlines might help!

Swiss has changed close to 200 engines on c series with a small fleet, baltic over 100, is that reliable?

Only the most recent 30 comments are shown to reduce server load. Click here to show the remaining comments

The Aviation Herald Apps
Android and iOS

Support The Aviation Herald

Euro

US$

Interview:

The human factor named "Simon Hradecky" and the team of man and machine

Get the news right onto your desktop when they happen