PW1500G engine failure A220 swiss

[Alistair_Heaton]

Swiss-Airbus A220 engine shows "unknown fault pattern"

Following the emergency landing of a Swiss aircraft in Graz and the death of a crew member, the investigation into the incident is in full swing. Initial analyses indicate a "previously unknown fault pattern" on an engine, Swiss wrote in an internal memo.

www.bluewin.ch

To note I pilot this type for a different airline.

I have zero inside knowledge.

There have been fume issues with engine seals but they seem to have systems to deal with that.

This is different due to previously unknown fault pattern.

 

[TugboatEng]

I'm curious to know if the fire suppression system was deployed on the failed engine. Google says the airplane has a Halon 1301 system. I don't imagine that's true as Halon 1301 production has long been banned. Meanwhile Halon 1301 alternatives have a higher tendency to decompose into hydrogen fluoride when heated. If smoke from the engine failure entered the cabin then it may be possible for the suppression agent to enter as well.

I ask this as it seems like a plausible case to cause death to one person while injuring few and leaving the rest unharmed. Of course this assume the death wasn't a stress related medical emergency.

 

[verymadmac]

That is a pretty nasty incident. I see the flightcrew were part of the five crew hospitalized, at Fl400 is one of the flight crew required to be wearing a mask?


Mild tangent, year ago I is testing a modification on a metroliner cabin air system where we blocked up all the cabin vents to force all the cabin heat to the cockpit when operating as a freighter* (there was no cockpit cabin split and no space for such a system). The first time we tested it, it really did smoke out the cockpit which makes me wonder if some of these events is caused material (oil etc) accumulating in the lines without issue until there is an event causing an elevation in bleed air temperature.

* They would fill the cabin with fish bins that would get sufficiently hot to smoke if they ran the cabin/cockpit heat system.

 

[Alistair_Heaton]

Not under EASA rules, I certainly never have. Its max ceiling is FL410.

I suspect your wonder is correct.

This aircraft is under 6 years old.

 

[Cool_Controls]

HFC-125 appears to be the replacment for halon 1301, its decomposition products are still pretty nasty (hydrogen fluoride). Those halon systems tend to hang around until they are discharged.

 

[Alistair_Heaton]

tug double checked for you.

Its definitely Halon engine fire suppression and also cargo holds, apu and cockpit portable fire extinguishers in the A220

They don't produce Halon anymore, but there isn't a shortage of it.

 

[TugboatEng]

I can't believe that aircraft have Halon 1301 on them considering how many more aircraft are in the sky versus 10 or 20 years ago. We have FM-200 on our tugboats built after 2005. I see that there are a few Halon 1301 alternatives. Halon 1301 is never used for new construction.

 

[Cool_Controls]

Fm200 is being phased out as well.

 

[Alistair_Heaton]

Seems the investigation has been expanded into the use and design of portable breathing equipment and how it's used.

No updates about the failure in the engine although there doesn't seem to be any worry it's a design issue.

 

[MintJulep]

One of the hospitalized crew has died.

Swiss flight attendant dies a week after plane's emergency landing due to smoke on board

A flight attendant aboard a Swiss passenger plane that made an emergency landing in Austria due to smoke in the cabin has died.

apnews.com

 

[Alistair_Heaton]

I have documentation on two types of PBE approved for the type.

Puritan Bennett KO2 powered rebreather type. You pull the straps forward which releases water into the potassium superoxide.

Essex PBE which is a pair of O2 cylinders which you snap apart putting it on to release the gas.

I don't know which type was used in the incident aircraft.

O2 chemical generators are regarded as dangerous goods for transport purposes when not fitted to an aircraft.

 

[TugboatEng]

Doing some reading about HFC-227ea or FM-200. The data sheets say that it's stable to 175C. I see that bleed air from turbine engines is up to 250C. I don't think that alone is going to cause decomposition but, the data sheets warn that certain reactive metals can act as a catalyst for decomposition, specifically aluminum or magnesium if powdered. I don't think there is much aluminum inside of these engines to get ground up during a failure but titanium is also a reactive metal and I assume there is a lot of it in the fan and compressor stages. I can't find any specific reference for compatibility with titanium.