Air Canada A319 hits turbulence

[ve3id]

Breaking news from CBC News:
_______________________________________________


Emergency crews are rushing to the Calgary airport in response to
reports that an Air Canadaflight from Cranbook, B.C.,has landed with
several seriously injured people on board.


Anybody know anything about this? CBC don;t normally use exaggerated headlines.

[AngrySquirrel]

Emergency landing

Calgary Herald

Published: Thursday, January 10, 2008
Emergency crews are on the scene at Calgary Airport after an Air Canada plane travelling from Victoria to Toronto was hit by turbulence and passengers were injured this morning.
Nine ambulances are lined up on the departures level, ready to take patients to hospital.
Duty inspector Richard Hinse said between six and eight people were seriously injured while other passengers sustained minor injuries.
"It went up and then sideways," said one passenger, who said a friend of hers was hurt. "She flew up to the ceiling and right down."

Traffic at the airport is being diverted.
An Air Canada Airbus A319 headed from Victoria to Toronto made the unscheduled stop in Calgary at about 8:30 a.m. MT.
More details to follow.

[SpeedbirdXK8]

According to recent CBC report the pax suffered injury whilst the aircraft encountered turbulence...

[Chap6168]

Latest CBC report:-

http://www.cbc.ca/canada/calgary/story/2008/01/10/injuries-landing.html

[robbreid]

Air Canada confirms emergency landing at Calgary

Thu 10 Jan 2008, 16:30 GMT

[- (javascript:sizeDown();)] Text (javascript:resetCurrentsize();) [+ (javascript:sizeUp();)]

TORONTO (Reuters) - Air Canada confirmed on Thursday that flight AC190, travelling to Toronto from Victoria, British Columbia, made an emergency landing at the Calgary, Alberta, airport because of unspecified passenger injuries.
The airline, owned by ACE Aviation Holdings Inc, said the Airbus A319 passenger list shows the plane was carrying 83 passengers and five crew members, but it said those numbers were based on the preliminary list and were subject to confirmation.
It also said the exact number of passengers taken to hospital was not available.

[Check Airman]

I'm hoping that the seatbelt signs were on when these people got injured. Nothing annoys me more than seeing folks walking around with the sign on. I'm convinced they think that pilots turn on the signs just because the chime sounds nice.

[BlueTui]

Annoys the hell out of me when they get up too.

http://news.bbc.co.uk/1/hi/7181801.stm

[robbreid]

http://flightaware.com/live/flight/ACA190/history/20080110/1425Z/CYYJ/CYYZ

[ab33t]

Yup my thoughts exactly hope those seat belt signs were on.

[jimbo canuck]

There was a press briefing at Calgary airport about an hour ago. Six people transported to hospital, at least one described as condition "yellow" meaning stable but potentially life threatening. No information given on the incident itself or how the injuries were caused.
Jimbo

[perkin]

Why all this talk of seat belt signs when no-one has posted the prevailing weather conditions yet? Could it not have been CAT? In which case, I feel sorry for the pax & crew wandering about at the time, pure bad luck & hope the injuries arent too severe...

[Granite Monolith]

http://www.flightplanning.navcanada.ca/cgi-bin/CreePage.pl?Langue=anglais&NoSession=NS_Inconnu&Page=forecast-observation&TypeDoc=html

http://www.flightplanning.navcanada.ca/Latest/anglais/produits/uprair/turb-haut-niv/Latest-hltcan.png

[FrequentSLF]

SLF here...
I am usually not posting on this threads for professionals, but frankly I do not deem this post appropriate, as well as at least another one that follows it.
Yes we are SLF, but we are not idiots and I believe that you should give more respect to the passengers that are obeying to the sign belts when are on.
May I remind you that without SLFs you will just one of the cargo pilots that are flying a number of cargo aircrafts around the world?
Are you absolutely confident that anytime you switch on the seat belt sign there is danger? or even worse...how many times the you did not switch it on time? This thread should be addressing other issues than the SLF being fasten. Where was the cabin crew? Did they enforce the seat bealt sign? We can go on forever...
Regards

[innuendo]

Part of Air Canada's onboard announcements include a reminder that seatbelts should be fastened at all times when the passenger is in their seat.

[Honeytruck]

Frequent SLF, I do take your point. And in my many years as cabin crew, I found that most passengers were conscientious and intelligent about fastening belts and staying seated when the signs came on. But there were also far too many who made a point of ignoring them. As crew, we came in for a lot of abuse if we tried to enforce the signs. The situation was possibly not helped by the hare-trigger reaction of some flight crews, to switch on the signs at the slightest hint of a bump. It's the old Cry Wolf phenomenon.. "But you're walking around!" was a common protest (Protest.. As if by asking them to strap in we were in some way trying to put one over on them..!) I somtimes had to bite my tongue not to snap back, "Ah yes, but we're insured!" It was especially galling with the citizens of a certain famously litigious country, whom we knew would be the first to rush bleating to a lawyer if they were injured; we sometimes wondered if that was the whole point.

[Mad (Flt) Scientist]

@Frequent SLF

Are you absolutely confident that anytime you switch on the seat belt sign there is danger

Frankly, from a safety point of view, it's hardly relevant if there's no danger yet the crew switch on the signs; it just means the signs are on more often than the absolute minimum amount of time. Unless the "false warnings" become so prevalent as to cause a "chicken little" effect, what matters is that warnings be given when needed as much as is possible. A few false alarms are the price you pay for being warned when necessary.

[perkin]

Well, looking at that map it seems there was been mod to sev CAT forecast...even so, I don't really see the benefit of ridiculing those who have been injured until the whole story is known. Postulate on what caused this event by all means, but to make the implication this was entirely the fault of the injured pax is just plain stupid!

[FrequentSLF]

@MLS
I do agree with your comments. False alarms are part of the "game". I do not agree on the comments that wants to put the blame on the SLF. IMHO it is outrageous a comment such as
"I'm hoping that the seatbelt signs were on when these people got injured. Nothing annoys me more than seeing folks walking around with the sign on. I'm convinced they think that pilots turn on the signs just because the chime sounds nice."
I do fully agree with the basic principle of the statement (i.e. seat bealts sign on...fasten the seat bealt and be quite on your seat).
I do question the sarcasm (i.e. sounds of chime) and the use/abuse of the sign by some airlines. Really what I could not agree is the tone of the statement...
Anyway, let me aks you a simple question...why the cabin crew most of the times is walking around when the seat belt sign is on? Would be simplier that all cabin crew sits down, this will not give excuses for the SLF to walk around too? Anyway my point is not to the need of respecting an instruction (fasten seat belt), I disagree on the way it was expressed.
Regards

[White Knight]

Look at the chart - moderate to severe CAT is nowhere near Alberta!! (Assuming this is the correct sigwx chart)

And yes - too many do have a hair-trigger reaction to a few little bumps!!! And Innuendo - FYI, most airlines these days have the same announcement. Certainly mandatory for us here in the sandpit..

[FrequentSLF]

Well, looking at that map it seems there was been mod to sev CAT forecast...even so, I don't really see the benefit of ridiculing those who have been injured until the whole story is known. Postulate on what caused this event by all means, but to make the implication this was entirely the fault of the injured pax is just plain stupid!

I wish my English knowledge could have expressed the above in my earlier posts.

[Eboy]

On certain airlines, at least in the UNITED States, the seat belt sign is treated as an advisory, not an order. Passengers will get up while the light is on, the crew will advise them that the light is on and they could be injured, and then they are free to use the lavatory or access the over head bins. If you want passengers seated while the seat belt sign is on, insist that they stay seated.

[DingerX]

Yeah, but in the UNITED states, we can get good info on Channel 9, and words like "severe" or "extreme" tend to propagate through the cabin pretty fast. Sorry, couldn't resist ;)

[Rollingthunder]

Eleven pax were taken to hospital. One has been released. Status on the others has been downgraded in seriousness. News stations still don't have their act together with the CBC reporting the incident took place just after take-off from Victoria. If that is correct the diversion would have been to Vancouver not continuing another hour and a bit to Calgary.

[reptile]

May I remind you that without SLFs you will just one of the cargo pilots that are flying a number of cargo aircrafts around the world?

Flying cargo does have it's advantages. And may I remind you: Without us, you would be a passenger on a bus. :E

[BullerBoy]

Whether the seat belt sign is off or on...........

Havign experienced CAT over the Pacific and seen my partner heading for the ceiling (quick reflexes prevented a head smack) I always have my seat belt buckled when I'm sitting in my seat. I may have it reallly loose to accomodate the beer-storage facility and to give me room to squirm around, but it isnt uncomfortable at all and it will sure as heck stop me from hitting the overhead bins.

Just my own little preventative measure.

[Dysonsphere]

Funny thing is as a PPL I find impossible to fly on an airliner without keeping my seat belt fastened

[Ron Waksman]

I am a former private pilot and the news director at Global TV News in Toronto. The pilots of the AC airbus 319 that made an emergency landing in Calgary say they landed the plane manually after the "incident", whether turbulence or what? Can anyone in this forum suggest what might have caused them to manually land the plane; autopilot failure due to turbulence? I'm speculating.

Please let me know.

Ron

[ve3id]

This is getting more into my area now:

An Air Canada flight which rolled suddenly from side to side then plunged in the air may have suffered technical problems, according to passengers interviewed after the plane was diverted to Calgary.

The pilot of Flight 190, heading from Victoria to Toronto, came over the intercom to say there had been a computer failure and that they were flying the plane manually, Richard Kool, a passenger from Victoria, said in an email to CBC News.



I am following this with renewed interest since I am presently teaching a course in computer engineering on preventing such failures!

[WannaBeBiggles]

I think what most SLF fail to realise is that air is clear, seeing turbulence is not like spotting a pothole in the road

Air crew have a job to do, they still move around the cabin because they need to, and they need to make sure that pax have heeded the sign. Exactly the same reason why crew of seagoing vessles are still moving around the deck to make sure everything is tied down in rough weather when most pax are looking green and clutching their sick bags!

[Ron Waksman]

Can any of you professional airline pilots/engineers elaborate on in-flight computer failure? Possible causes? Does the 319 have any common computer problems? I remember airbus jets having autopilot override issues in the very early days, but since resolved.

r

[sevenstrokeroll]

Frequent SLF...if there were no passengers, I would be flying cargo and GETTING PAID ALMOST TWICE AS MUCH. Fedex and UPS pilots are getting more than pilots at major US passenger carriers.

its because the passengers won't pay full freight (excuse the pun)...but enough of that.

ALWAYS keep your seatbelt fastened...try to time your bladder to avoid using the airborne toilet...if possible. and if you get up , finish your business and get back to your seat and seat belt. I know of one CAT occurence in which the seat belt sign WAS ILLUMINATED and a passenger went to the LAV...hit his head, broke his neck and is now a quad.

so be careful!
PS

we must also consider the remote possibility that wake turbulence may have caused the rolling moment.

BUT the computer situation is worth a good long look...hope there is more posting about this aspect...and a manual landing...did they have to use rudder and trim only? Or,was it just a non autopilot landing?

[ve3id]

From a computer engineering point of view, safety-critical systems are usually double or triple-redundancy. I believe in the airbus there are three control systems, each with a different type of processor and different software, although they are following the same algorithm. (My references are at work, or I would give a citation). The three different systems preclude the possibility of a virus or silicon mask fault from causing a failure in all three systems.

The actual algorithm is tested to the nth degree, and its implementation checked by the contractors for the three computers and airbus.

However, there is always the possibility that one or two systems may fail in a way that makes it look like the third system has failed,when in fact it is the only one working. This is called a Byzantine failure, after the difficulty associated with figuring out which of the Byzantine Generals is loyal and will attack an enemy. It is the computer engineer's worst nightmare, and a good reason to have two well-qualified and experienced pilots at the front of the bus!

[interpreter]

I have flown the Vancouver/Calgary route as a passenger on commercial aircraft (I'm a private pilot) dozens of times and have always felt that it was the worst area for CAT anywhere. You pass over the mountains in a clear blue sky and then sit on a roller-coaster almost all the way into Calgary.

[sevenstrokeroll]

mountain wave has been noted 700 miles downstream of mountains...we shall see..

[oldpax]

I fly frequently also and always keep my seat belt loosely fastened. I would like to say to SLF that in my experience a lot of pax do not realise the danger of wandering about the cabin,some cannot even open the toilet door ,some dont even hear the message "please put your seat in the upright position"!! I have seen pax walking to the toilet while almost touching down so not all pax are frequent flyers ,most think they are on a large Bus!!!

[CityofFlight]

:confused:
I fly frequently enough and do as many of you mention. Keep my seat belt on, loosely for this exact reason. But I have to question this "wandering around the cabin" statements....there's no place to wander! There's barely enough room for the beverage cart in the aisles, God help anyone if they have to wait to get back to their seat if the cart is blocking it by several rows. Since coach isn't allowed to use a vacant 1st class lav, we must stand in line quite often. I have often waited and waited to find an open time, then could wait no more.

From my experiences, this could easily be the factor that would cause a passenger to hit their head. And like another post mentioned, air is clear, the turbulence often hits first, THEN the pilot makes an annoucement.(unless there's been mention of such from another a/c passing through)

In appreciating the value of our roles in flight, please consider the factors that make many SLF's feel like more and more like freight and less like customers. :)

I feel better now....you may "go about the cabin..." ;)

[Check Airman]

I was not trying to imply that all pax are idiots. I think it's quite the opposite. However, there will always be the few bad apples who insist on ignoring the sign,and for such people, I have little pity if something bad happens.

The comment about the ding wasn't meant to be sarcastic, but I honestly wonder if they think it would be on if the pilots didn't think it necessary. Why on earth will the seatbelt sign be on?:ugh:

[CityofFlight]

Here's what I found on-line with some PAX comments. AP press is still reporting turbulence even though PAX mentions computer failure. :confused:


Air Canada flight AC190, carrying 88 people, was en route from Victoria, British Columbia, to Toronto and was diverted to Calgary for the emergency landing, officials said.

"It landed safely at 8:30 a.m. with a request for medical units to meet the aircraft to injuries on board the aircraft," he said.

Ambulances surrounded the jet and paramedics and tended to the injured.

Stuart Brideaux of Calgary Emergency Medical Services said 10 people were taken to a hospital, including six who are in stable condition. Four others suffered minor injuries, he said.

Earlier, Brideaux said nine had minor injuries. He said he may have misspoke earlier and that the 10 injured have been confirmed by the hospital, ambulance service and airline.

Air Canada said the preliminary passenger list indicates the Airbus A319 was carrying 83 passengers and five crew members.

"All of a sudden there were three big drops," passenger Andrew Evans said. "One major drop and then two more that went `Oomph! Oomph!' And the plane rolled a bit after that.

"I was in the very, very front seat of the plane and was watching dishes fly through the air," Evans said. "There was a crash. The cart tipped over and there was a lot of squealing.

"It was over and done with in 10 or 15 seconds," said Evans, who was on his way to Washington, D.C.

Passenger Jayne Harvey said the plane dropped sharply, then rolled left and right as the pilots fought to bring it under control.

The pilots came on the intercom "and said they were flying manually and that the computer had been knocked out," she said.

"I thought that that was it for me," said the Ontario nurse, who added she was "incredibly scared" as the plane bucked and rolled.

One female passenger who was not identified told media at the airport that when the plane hit the turbulence, her friend "flew up and hit the ceiling and went back down."


Copyright 2007 The Associated Press.

[fesmokie]

Ive been in the freighter's on and off for over 20 years and have driven through lots of stuff. Mountain wave's, clear air turb and so on. Only a few times was it severe enough ( in the freighter ) that we took action and asked for an altitude change. Once on the L-1011 it scared the crap out of us because we lost several thousand feet over the mountains and it was a wild ride. While flying Pax we always asked for an altitude change at the first sign of bumps cause we had to. My point is..that most of the time it really isn't that bad to the experienced crew however, a passenger can get quite rattled over it and even more so when 50 or 100 pax are all rattled and screaming at the same time, then the turbulance is at it's worse. Also it dosen't take much to launch an unrestrained and unsuspecting human into space ( or the overhead bins ) so that's why we all should wear our seatbelt's all of the time !!! :ugh:

Please don't flame me if you think I,m making lite of this particular incident cause I,m not.:= Just making a point.:}

[sweker]

"and said they were flying manually and that the computer had been knocked out,"

Much more familiar with the NG than A319, but is it likely that the 'severe' turbulence caused the AutoPilot to disconnect, requiring manual intervention from the PF?

If so, the Cap't could have easily come on the PA in a semi joking tone, saying something like "that was a big one, it even knocked off the autopilot". PAX translation equals "computer had been knocked out". While re-directing to Calgary, passengers have time to discuss what just happened.....and thus story twists alittle...."and said they were flying manually and that the computer had been knocked out,"

Just a thought....

[Longtimer]

Computer failure in this case = systems switched off (automatic) as designed. Crew flying manual to keep ahead of the problem. Final result = professional crew handled the situation and landed at the next available airport just in case there were serious injuries. The only big deal is what the press is making of it!!!!!

And of course those injured are now released from hospital as they only had "soft tissue" injuries (bruises). And if they had kept their seat belts on they too would not have suffered any injury. Among those treated were two crew members who did not enjoy the luxury of keeping their seat belts on while providing cabin service.

[ehwatezedoing]

This below is a better reading than any forum discussion or "news reports"

Extract from the CADORS (Civil Aviation Daily Occurrence Reporting System)

http://www.tc.gc.ca/aviation/applications/cadors/splash.htm
-"Enter"
-"National report"
-"Reporting date: 2008/01/10" -->"Search"
-Scroll down to Record #14
(I tried a direct link but it didn't worked)


Cadors Number: 2008C0093 Reporting Region: Prairie & Northern
---
Narrative: ACA 190, an A319 with 88 people on board, was en route from Victoria to Toronto when the crew advised ATC of an aircraft upset that resulted in the aircraft doing a roll. The flight was in the vicinity of ONSET intersection (Washington state) about 65 NM southwest of Cranbrook when the crew informed Seattle Center that they were having difficulty controlling the aircraft. It is not known at this point if there was a flight management system problem or whether this event was related to turbulence. Vancouver ACC accepted control of the aircraft at 1450z. The crew declared an emergency, requested diversion to Calgary International Airport and requested medical assistance upon arrival. ACA 190 landed about 30 minutes later at 1529z and stopped on Runway 34 for visual inspection of the aircraft by airport emergency response personnel. The crew then taxied off the runway at 1533z. It was reported that there are some passengers with serious injuries. Medical assistance was on standby upon arrival. TSB Edmonton has sent two investigators to YYC.

[Flash2001]

Latest from CBC is that all injured pax released from hospital. Pax interviews suggest that the aircraft rolled about 60 deg left and then pulled negative g. Possibly there was additional rolling. Duration of event about 15 sec. Very unclear as to whether CAT or electronic problems initiated the event.

I'll be interested in the report.

After an excellent landing you can use the airplane again!

[India Four Two]

Look at the chart - moderate to severe CAT is nowhere near Alberta!! (Assuming this is the correct sigwx chart) Having grown up in England and spent many years in Calgary, it always amuses me how little knowledge people in Europe have of the sheer size of Canada.

Saying that CAT over Ontario and Quebec affected this flight, is like saying CAT over Beirut affected a London to Paris flight.

For the benefit of the geographically challenged :), I have annotated the turbulence map that GM posted. I see from ehwhatezedoing's post, that the flight was 65nm SW of Cranbrook, just south of the border in Washinton, when the incident occurred. This is just about the beginning of the higher mountains, which extend all the way to the Alberta-BC border, so if it was a CAT event, this is a likely area. This forecast was issued 8 hours after the event, but I couldn't find the previous forecast.

http://i30.photobucket.com/albums/c309/india42/Turbulence-1.jpg

Just east of the BC border, the mountains stop abruptly, like this:

http://i30.photobucket.com/albums/c309/india42/cowleycamp.jpg

The Livingstone Range in the picture routinely generates lee waves up to at least 40,000' and you often have wave activity further west, which will be less organized than the front range waves and therefore probably more turbulent.

Note: It is not a coincidence that there are gliders in the picture (Cowley Airport).

The current data (14 hours later) shows strong westerly winds aloft and gusty surface winds from the west at Lethbridge, plus bars of cloud on the satellite images downwind of the Rockies all through Alberta and Montana, all of which point to wave activity. Can anyone find the METARs and Winds Aloft for Lethbridge and Cranbrook for 10 Jan 1200 - 1600Z?

And I've just noticed, what a suitable name for the intersection where the event occurred - ONSET.

[cwatters]

On the last long haul flight I took there were frequently at least 9 people queuing for the toilets (not the same toilet, I mean in total). Perhaps manufacturers should consider increasing the number or provide a safe means of queuing? Will be interesting to read the report on who was injured, where etc. I allways fasten belt while seated.

[RFFS]

As a frequent flyer and industry insider, i am constantly amazed by the actions of some pax, from the moment the arrive at the terminal its as if the rules apply to every one but themselve's.

If it was not so B***dy dangerous it would be amusing!

Safety brief followed by CC taking to there seats and belting up = pax standing and rummageing in the overhead bin, whilst in selective hearing mode ie only recieving orders from the wife/hubby/partner.

Capt... we will shortly be starting our decent into....... followed by seat belt signs = que for the toilets.

My particular favorite was pax, yes more than one, standing up and retrieving duty free ect whilst still decelerating after touchdown.

The total disregard for there own personell safety yet alone anyone elses beggers belief.
I am not saying that was the case mentioned in this thread, but sometimes you wonder what goes throught the heads when travelling by aircraft.

[FlyingWay]

for this situation , landed at the next available airport just in case there were serious injuries, and the crew did that nice

[Grazzhopper]

An autopilot failure which would produce erratic roll as reported by passengers on this flight is extremely unlikely. It is more likely that the autopilot disengaged as a result of extreme attitude changes caused by turbulence. The autopilot on this type of aircraft will automatically disengage when the bank angle exceeds 45 degrees or the pitch attitude exceeds 25 degrees nose up or 13 degrees nose down.

[rasobey]

@Eboy:

Great, so those passengers using overhead bins with seatbelt signs on and CAT, what happens when something fall out and injures someone who is actually taking heed of the Captain's recommendations?!

[A37575]

I fly frequently also and always keep my seat belt loosely fastened

I suggest the term "loosely" fastened was coined by cabin crew when making the initial welcoming PA in order to play down the fact that turbulence can hurt you if you are not properly strapped in. They want to avoid scaring passengers with warnings of the inherent danger of flight. Severe turbulence against a loosely fastened seat belt can damage your internal organs due to the rebound effect not present with a firmly tightened seat belt.

Re "sudden" encounters with turbulence. if it happens in cloud it is sometimes caused by incorrect use of the airborne weather radar. The aircraft flies into the top of a storm cell unseen on radar simply because the crew were paying insufficient attention to the tilt or gain setting on their radar. I have observed crews reading a newspaper on the flight deck while at night in IMC and no one evaluating storm cells in the distance until a huge jolt throws unsuspecting occupants in the cabin off their feet. The captain expressed surprise at the sudden appearance of a storm by saying where did that bastard come from when blind Freddy ccould have seen the tilt control was way to high to pick up nearby storm tops. I always first suspect crew incompetency when someone gets hurt by "unexpected" turbulence.

[Check Airman]

A3757,

I believe the term they use is "comfortably fastened".:)

That seems like a pretty sensible thing to do. It's not as obstructive as a car seatbelt. Once you have it fastened, you pretty much forget it's there IMO.

[sleeper]

RON "Can anyone in this forum suggest what might have caused them to manually land the plane; autopilot failure due to turbulence?"

While this may have been an autopilot failure, it may interest you to know that 9 out ot 10 landings are done manually all the time.

[Lost in Saigon]

I think it is more like 99 out of 100 landings are flown manually.

[sleeper]

check!

Agreed, it was just a figure of speach. Nowadays people seem to think that everything is done on automatics and on automatics only.

For the uninformed:
As far as I know there is no commercial aircraft for which an automatic take off is even possible.

[alph2z]

India Four Two

The predicted turbulence for around the time it happened was for moderate turbulence with some severe nearby.

You can see the stored chart at:

http://www.airdisaster.com/forums/showpost.php?p=534003&postcount=12

.

[Thunderbird4]

from the http://www.avcanada.caforum....

Hey Guys,

I was on AC 190 yesterday. I just wanted to say that from my point of view the crew did a awesome job. Two of the Three flight attendants were injured and continued to assist the passengers and prepare the cabin for landing. The Pilots kept us informed as to what happened and what we were doing. All I know is that we were in smooth air in cruise when the plane rolled abruptly to the left followed by a roll reversal to the right. There were then about 3 more roll reversal that were getting small in intensity. It seemed to me that after the first roll upset the crew was getting the Plane back under control. The first roll reversal was a very rapid movement. It was nothing that I have ever experienced before. It was a very violent disruption. As you can imagine anything that was not strapped down was airborne. I was lucky that my neither I nor my family was hurt. After the crew had the Plane back under control the Captain
made a PA and said that then had had a computer malfunction and that the problem had been isolated and that they were manually flying the Plane. The rest of the flight was smooth with a nice landing in YYC. I just wanted to say thank you to the crew for getting us on the ground safely.

Sean Atkinson
B757 FO

[407 Driver]

Reports say that the A-319 arrived in CYYC under "Direct Law".

The Internet give this definition of Direct Law....

DIRECT LAW
Direct law is the lowest level of computer flight control and occurs with certain multiple failures.
Pilot control inputs are transmitted unmodified to the control surfaces, providing a direct relationship between sidestick and control surface.
Control sensitivity depends on airspeed and NO autotrimming is available.
An amber message USE MAN PITCH TRIM appears on the PFD.
If the flight controls degrade to Alternate Law, Direct Law automatically becomes active when the landing gear is extended if no autopilots are engaged. If an autopilot is engaged, the airplane will remain in Alternate Law until the autopilot is disconnected.
There are no protections provided in Direct Law, however overspeed and stall aural warnings are provided.
The PFD airspeed scale remains the same as in Alternate Law.

In my humble opinion...it seems as if there is more information pointing to a massive comuter glitch over any turbulence issue? Why are the other 100's of trans canadian flight not also reporting some degree of turbulence??

Comments??

[Backward Blade]

407 Driver...! I gotta go and peruse an international forum not even including helicopters to find you and your ever welcomed opinions.! Nice "seeing" you again (aka Zazu) . Back on topic though...Good job on the crew regardless of the circumstances. Hope all works out well with the Pax that were injured. Anyone who has done any amount of flying, whether pilot or Pax,will have realized that sometimes your bodily functions do not time properly with the present functions of the machine involved!!! Have patience. Given the present Times I'm sure someone will be found to blame...as always.

Fly safe all
BWB

[fc101]

Could it be that because of the turbulence (let us assume it was turbulence at this point in time) that the aircraft switched from normal law (I guess) to
abnormal law (abnormal alternate law) which more or less means manual flying.

As for the captain announcing to the pax about "computer failure" - is this an easy way of explaing Airbus control logic to pax?

E145 driver moving to A32x...

[eagle21]

Hi everyone, my opinion is that a computer failure with this results is highly unlikely but not impossible.

Has anyone consider reading FCOM I 1.27.30 Page 7 ABNORMAL ATTITUDE LAWS?

Not many A32O pilots know in wich configuration they will end up after recovering from this abnormal attitude, this is:

In Pitch: Alternate law without protections with autotrim
In Roll: Ful authority direct law with yaw alternate law

There is no reversion to direct law when the gear is extended



During the abnormal attitude itself the laws are slightly different to the mentioned above.

I am not saying this is what happened but is certainly a scenario not many people are familiar with.

[sevenstrokeroll]

407

thanks for the first meaningful post in a long time on this thread.
while it may be a few days before we know the sequence of events, we now know what is meant by "landing manually"

In our sim training, direct law is initiated and the box is flown that way for awhile...some pilots prefer it to regular ops.


One does wonder if the plane is flying again...or if stress during recovery exceeded any limits?

while I know the A300 is not the A320, I am reminded of an american flight with an upset...pilots didn't advance power on leveloff and stalled.

[DBate]

sweker
Much more familiar with the NG than A319, but is it likely that the 'severe' turbulence caused the AutoPilot to disconnect, requiring manual intervention from the PF? and

407 Driver
In my humble opinion...it seems as if there is more information pointing to a massive comuter glitch over any turbulence issue?

Encountering severe turbulence on an 319 might cause the autopilot to disengage and the aircraft to revert to the so called 'Abnormal Attitude Law' (this is by design, althought turbulence must be really extreme for this to happen).

The Abnormal Attitude Law is 'direct control' with G-load protection. When control is regained, the aircraft reverts to 'alternate law', i.e.
Roll is 'direct'
Yaw is 'alternate'
Pitch is 'alternate'and stays in this condition until landing. And as far as I remember, autopilot is n/a, and a manual landing is mandatory when in Alternate Law.

Maybe this was the reason, why the crew was flying manually.
So, if this happenend, than there was no computer failure - the system worked as designed. But let's just wait for the report to be published in a couple of weeks.

Regards,
DBate
P.S. It's been a while since I flew an aircraft from the A320 family, so any current pilot who cares to correct me - go ahead.

eagle21 beat me by a couple of minutes with his post ;)

[simtronix]

Hello, this link below gives a few more details. I just placed a section of the article for quick viewing. I like the "This is not CSI" comment

http://www.cbc.ca/canada/story/2008/01/11/flight-calgary.html

"This is not CSI," Transportation Safety Board spokesman John Cottreau told the Canadian Press. "It's not just bing, bang, boom. There's an awful lot that goes on.

"We deal in facts. We don't deal in speculation. Sure, we can hypothesize, but those need to be scientifically examined and either proven or discounted."

The board has confirmed what many passengers have already said — that Air Canada Flight 190 not only lost altitude but also pitched violently from right to left before dropping 900 feet.

"The aircraft rolled to the right to about 35 degrees of bank and rolled to the left about 50 degrees of bank and effectively the auto pilot was disconnected," said Nick Stoss of the Transportation Safety Board.

[Norman Stanley Fletcher]

I may be repeating some of the excellent descriptions given by other Airbus pilots but for non-Airbus pilots it may be helpful to have a 'Noddy's guide' to Airbus fly-by-wire control laws. There are 4 recognised states of Airbus flight control capability depending on computer and hydraulic serviceability. They are known as Normal Law, Alternate Law, Direct Law and Mechanical Back-up.

'Normal Law' is the standard flight control mode that pilots see every working day. Most pilots will go their whole professional career and never see any other mode except in the simulator. It requires that most flight control computers are operating normally and all hydraulic systems are functioning correctly. That is the mode for which the Airbus has become famous, whereby such features as limited g-loading, a maximum bank angle of 67° and the inability to stall are provided. Alternate Law is a degraded mode that still provides certain protections but will allow the aircraft to stall and to overbank, for example.

There is a further sub-mode somehwere between Normal Law and Alternate Law known as 'Abnormal Attitude Law' which caters for a scenario where the aircraft is thrown into a flight regime way outside the situations normally catered for in Normal Law. I have no idea if that is what happened in this case, but to give you a feel for what the pilots may have experienced, these are the paramaters that would have to occur for Abnormal Attitude Law to be invoked:

Pitch attitude > 50° nose up or 30° nose down
Bank angle > 125°
Angle of attack > 30° or < - 10° (- 15° for A319 and A321)
Speed > 440 knots or < 60 knots
Mach > 0.91 or < 0.1

The system applies an abnormal-attitude law in pitch and roll if the aircraft exceeds any of these limits in flight. The law in pitch is the alternate law with no protection except load-factor protection and without auto trim. In roll it is a full-authority direct law with a yaw mechanical.When the aircraft has recovered from its abnormal attitude, the flight control laws in effect are :

in pitch : alternate law without protection with autotrim.
in roll : full authority direct law with yaw alternate law.
There is no reversion to direct law when the pilot extends the landing gear.

I hope that may be helpful to non-Airbus pilots, but in no way suggests that is what occured in this case. It nonetheless gives you a feel for the severity of the situation required to enter this scenario.

[jettrail]

@ India Four Two

METAR for Lethbridge:

http://english.wunderground.com/history/airport/CYQL/2008/1/10/DailyHistory.html?req_city=Lethbridge&req_state=AB&req_statename=Alberta

METAR for Cranbrook:

http://english.wunderground.com/history/airport/CYXC/2008/1/10/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

Unfortunately no winds aloft history found.

Regards

[old,not bold]

If I may intrude, for a moment...

What a clear piece of writing; many thanks. Illuminating.

But isn't >125 degrees bank rather more than a "severe" situation, as in "more than halfway to inverted"? I would have guessed that a severely abnormal situation might start at 60 degrees bank or even less, in a commercial jet.

Or am I muddling my degrees?

[IcePack]

Please do not jump up and shout at me. I AM NOT SAYING THIS COULD HAVE HAPPENED IN THIS CASE.

When my company first got their A320's we had similar incident. The cause was put down to the F/O sitting cross legged and his Knee pressing on to the side stick. If I remember correctly they thought either the pressure gradually increased untill the autopilot let go or that he moved and knocked the side stick hard over. Neither pilot could remember this happening but the FDR showed the side stick movement.
Again if I remember rightly the a/c went 60 deg one way then 60 the other as the other pilot grabbed his side stick to correct. Then a bit of dual stick input (it sums the inputs) untill things settled down. Luckily no one was hurt.

Anyway as a matter of interest. & be careful crossing your legs, especially with one ankle on the oposite knee in an Airbus. :eek:

[RevMan2]

Lufthansa requires passengers to wear seatbelts AT ALL TIMES when they're seated.

Cockpit also notifies SLF of any KNOWN expected turbulence, but it certainly makes sense to me.

Is there any reason NOT to comply with Jimmy Saville's "Clunk Click Every Trip" exhortation?

[BRUpax]

Lufthansa requires passengers to wear seatbelts AT ALL TIMES when they're seated

Many other airlines encourage this too.

However, the emphasis is "when seated". Not everyone might be seated at a given moment for a variety of valid reasons. This may have been the case here. We don't know, we weren't there.

I keep my seat belt fasten at all times when seated. I often reflect how that's not going to save me if we happen to hit unexpected turbulence as I make my way to the lavatory. Sod's Law!

[kevin broadbent]

I flew from ORD to CVG with AA and on approach not once were we told to 'belt up'

[sevenstrokeroll]

on the seat back in front of you on every US airliner is a small sign indicating that whenever you are seated you should fasten your seat belt.

[LEXAN]

One possible scenario could be the malfunction of both ELAC ( elevators an ailerons computer). In that case, the ailerons are lost and the autopilots as well.

[rex cramer]

what would happen if "someone" switched the elacs off then on in flight???????????????

[LEXAN]

To my knowledge, it is recommended not to reset the ELAC in flight if a not commanded roll action occurs during the flight.

[skidoo_driver]

Been a while since I flew any "bus", but isn't pitch alternate and roll direct the same regime as is blended in when the aircraft enters "FLARE" mode? In this regime, it's pretty much just a regular, old-fashioned airplane.

I remember one morning climbing out of YYZ over west Pennsylvania out of 380 on the way to 390 in an A330...literally smooth as glass from surface to about 383...not a cloud in the sky...and then all $%^& broke loose. CAT was so severe that we couldn't even read the FCU/Instruments. A/P kicked off and A/T was disengaged in record speed with consensus rapidly achieved that a rather more expeditious return than normal to 350 would be a sound course of action.

Moral of the story: keep your seatbelts fastened! :bored:

[Lemurian]

From Norman Stanley Fletcher and some others :
..."to give you a feel for what the pilots may have experienced, these are the paramaters that would have to occur for Abnormal Attitude Law to be invoked:

Pitch attitude > 50° nose up or 30° nose down
Bank angle > 125°
Angle of attack > 30° or < - 10° (- 15° for A319 and A321)
Speed > 440 knots or < 60 knots
Mach > 0.91 or < 0.1..."
All the above is correct as are all the posts dealing with flight control reversions.
They, IMHO, are hardly applicable in this case as :

They were on autopilot
A passenger was quoted as reporting that the captain came on the PA and said that " the A/P had been knocked-out and they were flying manually".
This points to an A/P disconnect.
The conditions are a lot smaller than those for a reversion :
-High speed protection is active (Vmo bust)
-Alpha protection is active (AoA greater than Alpha prot +1° )
-Pitch attitude over 25° nose up or 13° nose down
-Bank angle in excess of 45°

As everybody was talking about 50 to 60° bank angles and some porpoising, one at least of these reported values could have triggered an A/P disengagement.
Please note that in this case, they could have re-connected the A/P when calm conditions were resumed. The reason why they - apparently - did not could be explained by caution and - maybe - confusion as to the causes of the upset.

[sevenstrokeroll]

it seems that the crew changed altitudes looking for smoother air prior to the "upset". if that is the case, why was anyone standing? including the fa's? I would have told the fa's to delay service if turbulence was possible.

and if the crew did look for smoother air, it should have been obvious that this was a turbulence induced event. now, has the plane been put back into service or was it overstressed?

[Web-Footed Flyer]

Latest news from CBC french network is the upset would be caused by a close encounter with waqke turbulence from an american stealth aircraft.....?????:rolleyes: :rolleyes:

[ACL1011]

Here is the Anglo version:
http://www.cbc.ca/canada/calgary/story/2008/01/16/flight-cause.html

An Air Canada Airbus on its way from Victoria to Toronto dropped suddenly in midair likely because of the wake from a passing plane, according to a Calgary newspaper report.

The Calgary Sun quotes Real Levasseur, the chief investigator of the Transportation Safety Board, as saying there was a "high probability that an external force may have caused the incident."

Flight AC190 was diverted to Calgary on its way from Victoria to Toronto.
(CBC) The Airbus A319 had been flying for about 30 minutes on Jan. 10 when it suddenly rolled and dropped about 300 metres. Passengers said the pilots reported a computer failure onboard at the time.

Flight AC190 was diverted to Calgary, where 10 passengers and crew members were taken to hospital with mainly soft-tissue injuries. All were discharged several hours later.

The aircraft's roll of 46 degrees was described by an Air Canada pilot as an unusual occurrence. "The pitch caused by a regular turn generally ranges around 30 degrees," Serge Beaulieu, spokesman for the Air Canada Pilots Association, told the Sun. He also confirmed wake turbulence was a possible cause.

The incident happened at the edge of U.S. airspace near the B.C. Kootenay Mountains. The TSB has asked its U.S. counterpart to provide navigational recordings from the area.

Levasseur refused to speculate on the mystery aircraft, or to discuss the possibility it could have been a B-2 stealth bomber, according to the Sun report.

U.S. Air Force officials told the newspaper Tuesday that stealth bombers always leave a radar signature when they are not flying over a war zone.

This reminds me of a story a from friend of mine who was AC cabin crew. Disclaimer: (1) I am SLF; and (2) She told me this over 10 years ago, so I don't remember all the details.

She was flying out of Vancouver on a B767 and was in the cockpit when the two pilots suddenly looked concerned. Turns out, a US stealth jet was flying below them. I know she told me how many feet separated them, but I can't remember now. However, it was close enough that the two pilots were not impressed.

slinks back to steerage

[robbreid]

http://www.canada.com/victoriatimescolonist/news/story.html?id=077573c6-a8f8-4a0c-8cbf-ea1817111f0a&k=38168

Just posting the story...

[TechnoFreak]

If, as some posters are suggesting, this incident was caused by a computer failure, this would imply that the “violent” roll reversals were caused by movement of the control surfaces. Although it is not possible to know how violent these reversals were, anecdotal evidence suggests that they were well above that which is possible to induce via the control surfaces. This would support the hypothesis that this incident was initiated by some sort of turbulence related upset.

[dfish]

CBC News this evening is reporting that investigators are now looking into the possibility that wake turbulence was to blame.

Dave F.

[MidgetBoy]

I heard from a friend that a UA aircraft's turbulence caused it.

[dfish]

CBC mentioned a UA flight was close by..........

Dave F.

[Green Guard]

FrequentSLF (post 13)

"Are you absolutely confident that anytime you switch on the seat belt sign there is danger? or even worse...how many times that you did not switch it on time? This thread should be addressing other issues then the SLF being fastened. Where was the cabin crew? Did they enforce the seat belt sign? We can go on forever...
Regards


CBC mentioned a UA flight was close by..........

Dave F.

Too much bullsh1t, whenever this kind of turbulence happens. it is some kind of "clear air turbulence" or anything else but the crew error.
The 9o % chance is that the radar was u/s or the crew did not have radar in proper setting or did not even know how to use it properly.

[ex-beagle]

Green Guard,

That's a stupid comment you made about the crew not having the radar on. An even stupider comment is that you insinuate that they may not even know how to use it.

The aircraft hit clear air turbulence at 36,500 feet during daylight hours. The CAT may have been caused by a meterological event or by the wake turbulence from a passing aircraft.

Radar is used to detect thunderstorms. I would hazard a guess that there are very few thunderstorms in Canada in January. As I type this, the temperature outside my house is a balmy -12 degrees C. Not a lot of thunderstorms develop in these temperatures. I was flying over the Rockies the same day that Air Canada had it's jet upset. There wasn't any reason to have the weather radar on.

You show your ignorance by insinuating that this crew should have had their weather radar on or that they may not have even known how to use it.

Sir, you owe this crew an apology.

Ex-beagle

[Green Guard]

I hope and pray that you are right and I that I was wrong !
The time must tell the truth.

[barit1]

Air Canada A319 hits turbulence

Did the turbulence suffer any damage? :eek:

[MidgetBoy]

Well if you read the article, it said the turbulence went to one of the hospitals and suffered some soft tissue problems. :}

[CONF iture]

TSB Report (http://www.tsb.gc.ca/eng/rapports-reports/aviation/2008/a08w0007/a08w0007.asp)

[69rooster]

During the 18-second duration of the event, heading varied from 065ºM to 086ºM. The captain reacted to the rolls with a total of nine sidestick roll inputs, accompanied by coordinated rudder pedal deflections. Five sidestick inputs were to full travel of 20º. Seven successive rudder pedal inputs were made, with six cyclic reversals from left to right. Rudder deflection followed pedal inputs with maximum deflection of 6º left and 7º right.



Rudder input?

[mary meagher]

India Four Two shows a splendid grasp of Canadian geography, illustrated by his photograph of the Livingstone Range as seen from Cowley Airport. The glider pilots in the photo will be well acquainted with the properties of mountain lee wave which can smoothly elevate the glider to over 36,000 feet - or nearly rip your wings off in the rotor that lurks in the curlover! All of which can be exacerbated by jet streams flowing in contrary directions in a boundary layer. Although wave is often marked by lenticular clouds, if the air is dry they do not alway appear.

I believe this phenomenon does not necessarily show on radar. which should warn of the even more exciting conditions to be found in a cu nimbus..

[BarbiesBoyfriend]

69 Rooster

Thats weird. Most folk, including me, the very LAST thing you'd do is slam the controls about if in CAT.

Baffling. That action on the controls could cause an upset without any input from weather.

[J.O.]

This wasn't your run of the mill CAT encounter. This was an entry into the wake of a B747 which caused a significant roll when the aircraft was otherwise flying in smooth air. The startle factor in such an event is significant and the urge to make a correction would be difficult to ignore.

[fox niner]

IMHO rudder inputs are only necessary in the following cases:
1. Engine failures/fires/etc
2. crosswind takeoff's and landings
3. taxiing on a long, straight taxi track and thereby freeing your hand from the tiller to empty your coffee cup.

[atakacs]

In the Airbus A318/A319/A320/A321 series, it may be possible for a pilot to apply rudder control inputs that result in aerodynamically generated structural loads in excess of certification design limits and approaching ultimate loads.

Hmm... I was under the impression that the whole Airbus design philosophy was precisely to protect pilots against themselves. This is a serious breach IMHO.

[mostlylurking]

If I may make a comment on this issue:
As a frequent long distance traveller I have come to believe that the issue of the seat belt sign could be handled better by crew.
It would help if the crew could give some notice of imminent turbulence when possible.
It is quite annoying to make a dash back to your seat only to find that it is 10 min or more before the first bump. People get used to this delay and factor this into their decision to sit down and belt up.

It sometimes seems to me that the crew forget to turn the sign off.
I have often experienced that the sign goes on, followed by a slight bump and then an absolutely smooth ride for an hour or more with the light still on.
My worst experience was an AF flight across Africa with the light on for close to 3 hours and no turbulence worth mentioning.
To me it is inexplicable, especially when you are sitting there with your legs and eyes crossed.
If there is a good reason for the long duration, it would be helpful for the crew to say so, estimate how long they expect the light to be on and keep us updated – is it so difficult?
As it is I comply, but I’m quite sceptical of the necessity for it being on so long.

I have no idea how the crew predict CAT, other that from weather predictions or seeing bad weather below, so these comments are made in ignorance. Maybe someone can educate me?

[jurassicjockey]

Reminds me of a day dodging CB through Florida going north. Lots of red on the screen, and lots of deviating. Had the FA's secure the cabin and take their seats. Went around stuff for close to an hour with nary a bump. Some pax complained about the lack of service. Should have gone through a cell just to give them their money's worth.


Mostlylurking: Predicting bumps is not a science.