Transport Canada knew of jet engine limit
By Fred Vallance-Jones
The Hamilton Spectator
(Jan 10, 2007)
Transport Canada knew about an engine problem that could cripple Bombardier regional jets 13 years before it contributed to the 2004 fatal crash of an RJ in Missouri.
Transport Canada discovered the potentially catastrophic condition when testing the plane for certification in 1991. But outside the tight circle of Bombardier, engine manufacturer General Electric and Transport Canada, the aviation community that operated the regional jets was left unaware. The GE engines are installed on about 1,000 Bombardier regional jets, the plane type Air Canada Jazz flies between Hamilton and Montreal. Details of just how long the manufacturer and Canada's aviation regulator knew of the problem came yesterday as the U.S. National Transportation Safety Board released its report on the tragedy.
It blamed the pilots for the 2004 Pinnacle Airlines crash. They were on a ferry flight without passengers when they flew their plane to its maximum certified altitude of 41,000 feet. They lost speed and the plane started to fall from the sky. Both engines flamed out.
The pilots blundered more as they tried to recover, including flying the powerless plane too slowly. That led to core lock and doomed them.
"Simply adhering to standard operating procedures and correctly implementing emergency procedures would have gone a long way to averting this tragic accident," said safety board chairman Mark Rosenker.
Core lock is essentially a jam after a jet engine stops and cools suddenly.
GE doesn't accept that core lock occurred and said it can happen with any jet engine pushed beyond its limits. The company said flight manuals contained instructions to restart engines.
The safety board says while the manuals contained the procedures, including a "target" speed of at least 240 knots, pilots weren't told why they should fly that fast or that engines could lock up.
Officials for Bombardier and Ottawa could not be reached for comment.
http://www.hamiltonspectator.com/NASApp ... 4656511815
Another Transport Canada Debacle
Moderators: sky's the limit, sepia, Sulako, lilfssister, North Shore, I WAS Birddog
Pilots' behavior, actions cited in Pinnacle CRJ crash
Wednesday January 10, 2007
The Oct. 14, 2004, crash of a Pinnacle Airlines CRJ200 during a repositioning flight was owing to "unprofessional behavior, deviation from standard operating procedures and poor airmanship" on the part of the cockpit crew, "which resulted in an inflight emergency from which they were unable to recover," the US National Transportation Safety Board stated in a report issued yesterday.
Both pilots were killed when the aircraft, which was en route from Little Rock to Minneapolis-St. Paul, crashed about 3 mi. short of the Jefferson City airport, where they were attempting a deadstick landing. There were no passengers onboard and no injuries on the ground.
During the flight the pilots took the aircraft to its maximum operating altitude of 41,000 ft. for "personal and not operational issues," NTSB said. As a result of the maneuver, both engines shut down after what the Board described as a "pilot-induced aerodynamic stall. . .and their improper reaction to the resulting inflight emergency exacerbated the situation to the point they were unable to recover the airplane." Contributing to the accident was the engine core lock condition, "which prevented at least one engine from being restarted."
NTSB recommended that the aviation industry ensure training manuals contain information on high-altitude operations of RJs and that pilots receive adequate training to demonstrate their ability to identify and execute recovery from high-altitude engine stalls.
GE, which manufactured the CF34 engines powering the aircraft, said, "Tragically, the pilots. . .put the engines into a hazardous condition for which they are not designed or tested." It added, "core lock is a known industry phenomenon and can occur with any engine if operated outside of recommended flight procedures."
by Sandra Arnoult
Wednesday January 10, 2007
The Oct. 14, 2004, crash of a Pinnacle Airlines CRJ200 during a repositioning flight was owing to "unprofessional behavior, deviation from standard operating procedures and poor airmanship" on the part of the cockpit crew, "which resulted in an inflight emergency from which they were unable to recover," the US National Transportation Safety Board stated in a report issued yesterday.
Both pilots were killed when the aircraft, which was en route from Little Rock to Minneapolis-St. Paul, crashed about 3 mi. short of the Jefferson City airport, where they were attempting a deadstick landing. There were no passengers onboard and no injuries on the ground.
During the flight the pilots took the aircraft to its maximum operating altitude of 41,000 ft. for "personal and not operational issues," NTSB said. As a result of the maneuver, both engines shut down after what the Board described as a "pilot-induced aerodynamic stall. . .and their improper reaction to the resulting inflight emergency exacerbated the situation to the point they were unable to recover the airplane." Contributing to the accident was the engine core lock condition, "which prevented at least one engine from being restarted."
NTSB recommended that the aviation industry ensure training manuals contain information on high-altitude operations of RJs and that pilots receive adequate training to demonstrate their ability to identify and execute recovery from high-altitude engine stalls.
GE, which manufactured the CF34 engines powering the aircraft, said, "Tragically, the pilots. . .put the engines into a hazardous condition for which they are not designed or tested." It added, "core lock is a known industry phenomenon and can occur with any engine if operated outside of recommended flight procedures."
by Sandra Arnoult
EXECUTIVE SUMMARY
On October 14, 2004, about 2215:06 central daylight time, Pinnacle Airlines flight 3701 (doing business as Northwest Airlink), a Bombardier CL-600-2B19, N8396A, crashed into a residential area about 2.5 miles south of Jefferson City Memorial Airport, Jefferson City, Missouri. The airplane was on a repositioning flight from Little Rock National Airport, Little Rock, Arkansas, to Minneapolis-St. Paul International Airport, Minneapolis, Minnesota. During the flight, both engines flamed out after a pilot-induced aerodynamic stall and were unable to be restarted. The captain and the first officer were killed, and the airplane was destroyed. No one on the ground was injured. The flight was operating under the provisions of 14 Code of Federal Regulations Part 91 on an instrument flight rules flight plan. Visual meteorological conditions prevailed at the time of the accident.
The safety issues discussed in this report focus on flight crew training in the areas of high altitude climbs, stall recognition and recovery, and double engine failures; flight crew professionalism; and the quality of some parameters recorded by flight data recorders on regional jet airplanes. Safety recommendations concerning these issues are addressed to the Federal Aviation Administration.
NTSB Synopsis - Public Meeting of January 9, 2007
On October 14, 2004, about 2215:06 central daylight time, Pinnacle Airlines flight 3701 (doing business as Northwest Airlink), a Bombardier CL-600-2B19, N8396A, crashed into a residential area about 2.5 miles south of Jefferson City Memorial Airport, Jefferson City, Missouri. The airplane was on a repositioning flight from Little Rock National Airport, Little Rock, Arkansas, to Minneapolis-St. Paul International Airport, Minneapolis, Minnesota. During the flight, both engines flamed out after a pilot-induced aerodynamic stall and were unable to be restarted. The captain and the first officer were killed, and the airplane was destroyed. No one on the ground was injured. The flight was operating under the provisions of 14 Code of Federal Regulations Part 91 on an instrument flight rules flight plan. Visual meteorological conditions prevailed at the time of the accident.
The safety issues discussed in this report focus on flight crew training in the areas of high altitude climbs, stall recognition and recovery, and double engine failures; flight crew professionalism; and the quality of some parameters recorded by flight data recorders on regional jet airplanes. Safety recommendations concerning these issues are addressed to the Federal Aviation Administration.
NTSB Synopsis - Public Meeting of January 9, 2007
Here are links that have information from Bombardier and GE.What is a “core lock” event?
The engine core hardware heats up during high power operation. There is radial and axial growth in the turbine static and rotating parts. Because the static parts have a lower mass and more direct exposure to flowpath air, the thermal time constant for growth of the stator hardware is faster than that of the rotating parts (rotors and inter-stage seal (ISS)) and initially the stator grows away from the rotor. Over the course of a Takeoff and Climb to cruise altitude, the rotating and static hardware reach an equilibrium condition and the labyrinth seals wear a track in the stationary seal. Under normal engine operating conditions, there is sufficient clearance between the core rotor and the stator such that the core rotor is free to turn. When the engine is shutdown at altitude, the core begins to cool and the stator, including the static ISS, contracts at a faster rate than the adjacent rotating parts in both the radial and axial direction because of its faster thermal time constant. The relative rate of cooling of the stator and rotor results in an alignment of the rotating seal knife-edges aft of the normal operating groove in the static seal. If the clearances are tight enough and the relative cooling rates are right, contact can occur between the static and rotating seal elements. The resulting stiction can temporarily prevent the rotor from turning when only the force of ram air is applied to the core. Air turbine starter (ATS) torque has been shown adequate to overcome this stiction.
NTSB Exhibit - GE
NTSB Exhibit - Bombardier
Its only due to the bullet-proof GE engines that they didn't blow up while these doofi were trying to get up to 410. Mishandling this aircraft so badly that both engines flamed out, and someone is trying to blame the manufacturers? These aircraft were in service for nearly a decade before the first catastrophic occurred.
Heat them up 'til they're red hot then blow the flame out?
Give me a break.
With all due respect, Widow, blaming TC for anything to do with this sad event is unreasonable.
Heat them up 'til they're red hot then blow the flame out?
Give me a break.
With all due respect, Widow, blaming TC for anything to do with this sad event is unreasonable.
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
I should have used a different thread title certainly, however my point is that Transport Canada knew about the condition when certifying in 1991, and that "The safety board says while the manuals contained the procedures, including a "target" speed of at least 240 knots, pilots weren't told why they should fly that fast or that engines could lock up."xsbank wrote: With all due respect, Widow, blaming TC for anything to do with this sad event is unreasonable.
and
"NTSB recommended that the aviation industry ensure training manuals contain information on high-altitude operations of RJs and that pilots receive adequate training to demonstrate their ability to identify and execute recovery from high-altitude engine stalls."
Did you read the NTSB synopsis as to probable cause? "Contributing to this accident was 1) the engine core lock condition, which prevented at least one engine from being restarted, and 2) the airplane flight manuals that did not communicate to pilots the importance of maintaining a minimum airspeed to keep the engine cores rotating."
I don't know, is this core-lock thing something that doesn't matter until it kills someone 100%?
This is not my "specialty", I just don't think it sounds good that there is a problem, and the pilots are not told it exists - only that they shouldn't do what might cause it. Most of us are more apt to follow the rules if we understand why they exist.
Former Advocate for Floatplane Safety
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Vickers vanguard
- Rank 7
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- Location: YUL
CD wrote:Here are links that have information from Bombardier and GE.What is a “core lock” event?
The engine core hardware heats up during high power operation. There is radial and axial growth in the turbine static and rotating parts. Because the static parts have a lower mass and more direct exposure to flowpath air, the thermal time constant for growth of the stator hardware is faster than that of the rotating parts (rotors and inter-stage seal (ISS)) and initially the stator grows away from the rotor. Over the course of a Takeoff and Climb to cruise altitude, the rotating and static hardware reach an equilibrium condition and the labyrinth seals wear a track in the stationary seal. Under normal engine operating conditions, there is sufficient clearance between the core rotor and the stator such that the core rotor is free to turn. When the engine is shutdown at altitude, the core begins to cool and the stator, including the static ISS, contracts at a faster rate than the adjacent rotating parts in both the radial and axial direction because of its faster thermal time constant. The relative rate of cooling of the stator and rotor results in an alignment of the rotating seal knife-edges aft of the normal operating groove in the static seal. If the clearances are tight enough and the relative cooling rates are right, contact can occur between the static and rotating seal elements. The resulting stiction can temporarily prevent the rotor from turning when only the force of ram air is applied to the core. Air turbine starter (ATS) torque has been shown adequate to overcome this stiction.
NTSB Exhibit - GE
NTSB Exhibit - Bombardier
Thanks CD for the links you provided
Core lock, in this case, resulted from a double-engine flame-out which resulted from execrable aircraft handling from the two who were flying it. Classical accident chain.
My understanding is that during a double-flameout scenario at altitude, you stuff the nose down in order to get re-light speed, something all RJ and 604 pilots are trained for in the sim. Problem is, it never happens - this is the first real one.
My understanding is that during a double-flameout scenario at altitude, you stuff the nose down in order to get re-light speed, something all RJ and 604 pilots are trained for in the sim. Problem is, it never happens - this is the first real one.
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
Widow:
I think you are a little off base on this one. The cockpit voice recording is used by Delta for training. I wont go into all the sordid details, but suffice it to say these two pilots did just about everything wrong, from switching seats at the beginning, zoom climbing, and, of course, flying a wrong climb profile. Then, after the failure, switching seats back, not declaring an emergency, improper restart procedures...I could go on.
You may not like TC but if there ever was a case of pilot error this is a classic example.
Slagging TC on this one damages your credibility (in my opinion) on your other mission.
Contact Delta or the FAA and see if you can get a copy of the cockpit recording. Listen to it, and then see if you can find a way to blame TC for any of what happened. here.
I am not a particular fan of TC and have had my days with them, but this is not one of those cases. dumb , stupid, inexperienced pilots, who got off their leash.
You see it all the time in Canada when pilots get cut loose on ferry flights.
They seem to lose all sense of professionalism. Their is a king air in the mountains around Vancouver....and a few northern flights where B1900's were zoom climbed and banked over hard in the circuit because there were no passangers on board.
I think you are a little off base on this one. The cockpit voice recording is used by Delta for training. I wont go into all the sordid details, but suffice it to say these two pilots did just about everything wrong, from switching seats at the beginning, zoom climbing, and, of course, flying a wrong climb profile. Then, after the failure, switching seats back, not declaring an emergency, improper restart procedures...I could go on.
You may not like TC but if there ever was a case of pilot error this is a classic example.
Slagging TC on this one damages your credibility (in my opinion) on your other mission.
Contact Delta or the FAA and see if you can get a copy of the cockpit recording. Listen to it, and then see if you can find a way to blame TC for any of what happened. here.
I am not a particular fan of TC and have had my days with them, but this is not one of those cases. dumb , stupid, inexperienced pilots, who got off their leash.
You see it all the time in Canada when pilots get cut loose on ferry flights.
They seem to lose all sense of professionalism. Their is a king air in the mountains around Vancouver....and a few northern flights where B1900's were zoom climbed and banked over hard in the circuit because there were no passangers on board.
Like I said before, I should certainly have used a different thread title, but I didn't say anything when I posted the article. CD, good man that he is, made sure we all had as much information as possible before anyone did say anything.trey kule wrote: Slagging TC on this one damages your credibility (in my opinion) on your other mission.
But I still don't understand. If the problem existed at certification, why wasn't it rectified prior to?
I didn't "blame" the accident on the core-lock phenomena, the NTSB found it to be a contributing factor and raised concerns about the dissemination of knowledge regarding the problem.
I don't think I "slagged" TC either (except perhaps with the poor choice of title, which did get everyone reading). I'm just trying to understand how things work, and if that damages my credibility, then so be it.
Former Advocate for Floatplane Safety
Re: Another Transport Canada Debacle
Widow wrote:I don't think I "slagged" TC either (except perhaps with the poor choice of title, which did get everyone reading). I'm just trying to understand how things work, and if that damages my credibility, then so be it.
Widow wrote:Transport Canada knew of jet engine limit
By Fred Vallance-Jones
The Hamilton Spectator
(Jan 10, 2007)
Transport Canada knew about an engine problem that could cripple Bombardier regional jets 13 years before it contributed to the 2004 fatal crash of an RJ in Missouri.
Transport Canada discovered the potentially catastrophic condition when testing the plane for certification in 1991. But outside the tight circle of Bombardier, engine manufacturer General Electric and Transport Canada, the aviation community that operated the regional jets was left unaware. The GE engines are installed on about 1,000 Bombardier regional jets, the plane type Air Canada Jazz flies between Hamilton and Montreal. Details of just how long the manufacturer and Canada's aviation regulator knew of the problem came yesterday as the U.S. National Transportation Safety Board released its report on the tragedy.
I guess you're right. It wasn't you who slagged TC, it was Mr. Fred Vallance-Jones.
I agree with trey kule on this one. You have lost some credibility. Especially if you are arguing semantics regarding the fact that you just posted the article rather than writing it.
Posting the article coupled with the thread title contributes to the perception that you believe TC was responsible for the crash.
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Jimmy Mack
- Rank 2
- Posts: 69
- Joined: Tue Sep 05, 2006 6:49 pm
Widow wrote:"The safety board says while the manuals contained the procedures, including a "target" speed of at least 240 knots, pilots weren't told why they should fly that fast or that engines could lock up."
I think most pilots agree that procedures are there for a reason; knowing the ins and outs of why you must do something in a certain situation is more knowledge than most can be burdened with. There was a procedure for this event, it ovbiously was not followed, with the un-surprising result.Widow wrote:This is not my "specialty", I just don't think it sounds good that there is a problem, and the pilots are not told it exists - only that they shouldn't do what might cause it. Most of us are more apt to follow the rules if we understand why they exist.
JM
I think the limitation here is certification - the aircraft was tested as per the 'normal' testing regime (whatever that includes) and the aircraft passed. A very good comparison would be that AA Airbus that lost its vertical fin at New York - the aircraft was not certified for full and complete rudder travel, full deflection from side to side; that was how the rudder was operated and the tail fell off. Now that is a whole different bag of snakes that I don't wish to stir up...
I believe that aircraft are certified to perform as advertised if they are operated within the limitations set forth in the aircraft Ops. Manual.
Now I know that all aircraft that come out of the B. factory are flown by production test pilots to ensure compliance and that nothing was missed in the factory. During this flight the aircraft is flown into a full aerodynamic stall (never done in operations) and both the engines are shut down and re-lit, a total electrical failure is simulated - you get the picture.
I believe that aircraft are certified to perform as advertised if they are operated within the limitations set forth in the aircraft Ops. Manual.
Now I know that all aircraft that come out of the B. factory are flown by production test pilots to ensure compliance and that nothing was missed in the factory. During this flight the aircraft is flown into a full aerodynamic stall (never done in operations) and both the engines are shut down and re-lit, a total electrical failure is simulated - you get the picture.
"What's it doing now?"
"Fly low and slow and throttle back in the turns."
"Fly low and slow and throttle back in the turns."
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Cat Driver
- Top Poster
- Posts: 18921
- Joined: Sun Feb 15, 2004 8:31 pm
For a non aviation trained outsider she is a lot more knowlegable than a lot of the so called professionals here.
Give her some slack, at least she is trying to rectify problems in aviation.
Give her some slack, at least she is trying to rectify problems in aviation.
The hardest thing about flying is knowing when to say no
After over a half a century of flying no one ever died because of my decision not to fly.
After over a half a century of flying no one ever died because of my decision not to fly.
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the_professor
- Rank (9)
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As an aside, does Jazz ever fly their RJ's higher than FL390? If they do, I've never seen it.
Of course, maybe none of their routing legs are long enough to permit the 600-700nm climb that would be required to get to that altitude, during which they try to hit every other aircraft in the sky with their 500ft/min climb... If every aircraft climbed as poorly as the RJ, airspace capacity in this country would be cut by 50%. I guess those pilots found that out the hard way. It is not meant to be a high-flyer.
Of course, maybe none of their routing legs are long enough to permit the 600-700nm climb that would be required to get to that altitude, during which they try to hit every other aircraft in the sky with their 500ft/min climb... If every aircraft climbed as poorly as the RJ, airspace capacity in this country would be cut by 50%. I guess those pilots found that out the hard way. It is not meant to be a high-flyer.
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Commonwealth
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The process of aircraft design is a complicated affair. Designers often have to compromise in one area to increase safety and efficiency in another. I do not doubt the manufacturer knew about the risk of core lock, but that risk was mitigated by the implementation of procedures.
As far as training goes, these pilots may have benefited from more knowledge about their aircrafts’ systems. After reading the CVR transcripts though, I doubt any amount of training would have helped these fellows.
As far as training goes, these pilots may have benefited from more knowledge about their aircrafts’ systems. After reading the CVR transcripts though, I doubt any amount of training would have helped these fellows.
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the_professor
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Not sure I would anymore. Just look at all the recent threads trying to place blame on ATC for accidents that clearly have nothing to do with us.cpl_atc wrote: One engine out -- ok, bad day, but shit happens... However, if you tell me that *both* your engines are out, I'm probably going to suggest pointing you at an airport RIGHT NOW.
I figure if we keep going down this road, (in no small part to frivolous lawsuits) my reaction to protect myself would be, "ABC check you are declaring an emergency, you're on your own."
I have seen numerous postings on this board from irate pilots when it is stated that an accident has occurred because of pilot error, but the posters seem to have no problem placing blame on the controllers and even TC when there is no evidence to support their theories.
