Brussels Airlines - 6 incidents in 3 weeks (RJ1H flaps)
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after 6 years on the 146/RJ 100 / 85 flaps are very big and powerful and that`s why its got so many flap problems. You have flap computers that give low rate flaps at the drop of a hat with any problems, i think any driver knows the ground reset procedure off by heart! and other problems and the safety lanes kick in to lock flaps in position to prevent asymmetric flap as this will kill you!. The RJ had a better drive shaft than the 146 to stop it breaking if you made a flap reversal selection but still retained the same safety system, with flap fail you had hyd safety brakes activate. With any flap down reduced flap landing not a problem but flapless was very fast and expect to have brake overheat / fire. You needed a very long runway at high weights. Turb use to "re rack" the flap computers and cause problems. also incorrect selection, not being positive with what you wanted also created a flap fault. Faulty sensors on flaps or selection lever would generate failures also electrical spikes would give you a flap fault. Its one of those RJ things!. Just like the air system! lots of dings to keep you awake!. May find that the start of winter ops is causing problems, liberal use of De-ice in the wrong places often causes problems.
It depends how you use the brakes. I have never seen more than 650 degrees on a flapless. Landing distance required is usually around 2500 metres depending on weight.
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Thanks for that DHC.
I knew it couldnt have been such a "no problem" event. That sort of thinking is excatly why there are so many crashes in my part of the world!
Sure now with so many of these aircraft around, and for the length of time they have been in service, someone could have designed something to work these kinks out? Why hasn't a CAA around the world somewhere gone... "Now hang on a minute"
I knew it couldnt have been such a "no problem" event. That sort of thinking is excatly why there are so many crashes in my part of the world!
Sure now with so many of these aircraft around, and for the length of time they have been in service, someone could have designed something to work these kinks out? Why hasn't a CAA around the world somewhere gone... "Now hang on a minute"
I have a terrible confession to make. I only flew the BAe146 for 19 years so I quite obviously do not know what I am talking about. You might possibly end up with the flaps stuck up or at any other intermediate position but I have never ever heard of anyone having a flap asymmetry.
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Uh JW, I never said that you didn't know what you were talking about?
He didnt say that it happens all the time, just said that if it happens, it will kill you, as opposed to what someone else had said earlier.
My problem is with the "Its no problem" attitude. 99.9999% of the time, it isnt a problem. But you only need the .0001%. Just like winning the lottery.
In the cockpit, I'm not the type of person that will go "Oh my god, we are going to die." at every issue.
But I still believe that prevention is better than cure. And surely from an economic stand point, it is better to sort the issues than having to drag the plane into maintence to fix it?
He didnt say that it happens all the time, just said that if it happens, it will kill you, as opposed to what someone else had said earlier.
My problem is with the "Its no problem" attitude. 99.9999% of the time, it isnt a problem. But you only need the .0001%. Just like winning the lottery.
In the cockpit, I'm not the type of person that will go "Oh my god, we are going to die." at every issue.
But I still believe that prevention is better than cure. And surely from an economic stand point, it is better to sort the issues than having to drag the plane into maintence to fix it?
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With regards to flap asymmetry there has never been an incident on the 146 / RJ. The system works and that`s why the flap safety lanes are there. Just don`t turn the Hyd off!. The weak point is the the flap computer and sensors. The drive train was improved with the RJ.
As i stated flapless landing is an issue at high weights (146-300, RJ100) 40200KG is a lot of energy to loose and an approach speed of 190kts +. It never fails when your 36000KGS!
In terms of risk and safety, flapless is a practiced sim training item and well within the scope of an average crew on the worse day. A reduced flap landing is not going to be an issue. Flap 24 is a normal landing flap position and anything else is a bonus. (unless you are going somewhere short like LCY).
I`m sure Brussels airlines will find the problem and fix it. It was always the way that several aircraft in the fleet tended to develop the same kind of problems around the same time normally due to time in service and similar factors affecting the aircraft.
As i stated flapless landing is an issue at high weights (146-300, RJ100) 40200KG is a lot of energy to loose and an approach speed of 190kts +. It never fails when your 36000KGS!
In terms of risk and safety, flapless is a practiced sim training item and well within the scope of an average crew on the worse day. A reduced flap landing is not going to be an issue. Flap 24 is a normal landing flap position and anything else is a bonus. (unless you are going somewhere short like LCY).
I`m sure Brussels airlines will find the problem and fix it. It was always the way that several aircraft in the fleet tended to develop the same kind of problems around the same time normally due to time in service and similar factors affecting the aircraft.
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I think some here are jumping to conclusions over these reports. Although I agree that the statement "Flaps did not extend" might infer a flapless condition it can equally mean "...did not extend fully" which is an entirely different thing. Yet most of the reports in the first post merely reported "flap problems" so nothing at all is stating flapless. And let's not get too het-up over brakes that are designed to get hot getting hot either, isn't that what they're supposed to do.
I have a vague recollection (some might argue it's my normal state) of grease being implicated on the assymetry lockouts that occur so readily on the 146. Excessive grease or using the "wrong" kind formed up with ice to cause a restriction, and the assymetry protection is so over-sensitive it only has to be a little one, in the freedom of movement and Pop! Lockout. Changing to a differrent type of grease and/or being more sparing with it sorted the problem.
This is the time of year when the first real icing is experienced at flap extension levels and if the engineers have got in the habit of slapping the stuff on over the summer what do you suppose happens next? The engineering solution really might be as simple as an oily rag.
Whether or not that is correct in this particular instance something that simple can cause a spate of incidents resulting in press attention, wild speculation here and handbags at dawn...
It really is no big deal. Jeez, I fear some modern aviators are so insulated from reality by modern systems that they're in danger of becoming far too precious over non-events like non-standard flap settings or unfamiliar looking temps on the BTIs. Guys, there is a huge range of grey shades in between black and white, I know it isn't the modern way to recognise this, but they're still there, whether or not it is trendy to admit it.
The assymetry system is there to prevent hazardous conditions and it works very well indeed. The aircraft and their contents are being kept safe and pilots are merely using alternative procedures to do so. What's the beef?
Whatever happened to Airmanship and judgement?
I have a vague recollection (some might argue it's my normal state) of grease being implicated on the assymetry lockouts that occur so readily on the 146. Excessive grease or using the "wrong" kind formed up with ice to cause a restriction, and the assymetry protection is so over-sensitive it only has to be a little one, in the freedom of movement and Pop! Lockout. Changing to a differrent type of grease and/or being more sparing with it sorted the problem.
This is the time of year when the first real icing is experienced at flap extension levels and if the engineers have got in the habit of slapping the stuff on over the summer what do you suppose happens next? The engineering solution really might be as simple as an oily rag.
Whether or not that is correct in this particular instance something that simple can cause a spate of incidents resulting in press attention, wild speculation here and handbags at dawn...
It really is no big deal. Jeez, I fear some modern aviators are so insulated from reality by modern systems that they're in danger of becoming far too precious over non-events like non-standard flap settings or unfamiliar looking temps on the BTIs. Guys, there is a huge range of grey shades in between black and white, I know it isn't the modern way to recognise this, but they're still there, whether or not it is trendy to admit it.
The assymetry system is there to prevent hazardous conditions and it works very well indeed. The aircraft and their contents are being kept safe and pilots are merely using alternative procedures to do so. What's the beef?
Whatever happened to Airmanship and judgement?
Bring back the Dak!
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Am with JW411 (quite literally) all the way on this one. In the early days it was found that the clay, (a component of this and most greases), was to a degree hygroscopic, and in freezing conditions the grease "firmed-up" and stopped the flaps deploying. A change of spec, some experimentation as to how much and where, saw the problem solved.
As the usual lock-out occured immediately when deploying from flaps zero to any other setting, (so they never actually moved), we pilots also contributed to reducing the problem. As a lock-out is caused by a sensing of the degree of resistance to movement, we simply unloaded some of the aerodynamic load by selecting flap at a speed well below the book limit for the amount of flap being selected, (within minimum manoeuvring constraints of course).
It worked. Maybe present-day drivers might like to consider this rationale if the problem ever starts occurring in their fleets.
As the usual lock-out occured immediately when deploying from flaps zero to any other setting, (so they never actually moved), we pilots also contributed to reducing the problem. As a lock-out is caused by a sensing of the degree of resistance to movement, we simply unloaded some of the aerodynamic load by selecting flap at a speed well below the book limit for the amount of flap being selected, (within minimum manoeuvring constraints of course).
It worked. Maybe present-day drivers might like to consider this rationale if the problem ever starts occurring in their fleets.
Just to get things into perspective, I recall getting airborne one filthy winter night from Copenhagen. I was training a new F/O who had come from the Dornier 228 and he was the pilot flying. He had not done many sectors on the BAe146 but he was a tidy pilot.
The flaps stuck at 18 degrees after take-off. I think he expected me to take over but I asked him what he was going to do next? And so it was that we went through the flap fault/flap inop checklist and, surprise, surprise, were now faced with an 18 degree flap let down and landing in very ****ty conditions.
I basically told him "You got us into this mess so you can get us out of it".
You will be astonished to learn that he did a great job (I knew he would).
Two things come out of this:
a: The BAe146 with abnormal flap situations is not a difficult aircraft to handle.
b: My student's confidence level in the aircraft and in his own ability went up hugely that night.
Finally, and I mean finally, I would say to my friend in Botswana that if he is looking to rid aviation of a 0.0000000001 risk factor then he is on a complete loser. What he is trying to say is that if a B737 were to lose a wing on take-off, then the situation would not be recoverable but should be.
Get a life, that's the way the cookie crumbles.
P.S. The last time I went to Francistown was from Matsapa. WANELA were flying DC-3s and DC-4s. Shortly afterwards, someone filled one of the DC-4s with AVTUR (JET A1) instead of AVTAG (AVGAS). I think they were all killed.
So maybe, instead of making aeroplanes 100% safe, you should concentrate on the 50/50 situations like putting the correct fuel into your aeroplane in the first place?
The flaps stuck at 18 degrees after take-off. I think he expected me to take over but I asked him what he was going to do next? And so it was that we went through the flap fault/flap inop checklist and, surprise, surprise, were now faced with an 18 degree flap let down and landing in very ****ty conditions.
I basically told him "You got us into this mess so you can get us out of it".
You will be astonished to learn that he did a great job (I knew he would).
Two things come out of this:
a: The BAe146 with abnormal flap situations is not a difficult aircraft to handle.
b: My student's confidence level in the aircraft and in his own ability went up hugely that night.
Finally, and I mean finally, I would say to my friend in Botswana that if he is looking to rid aviation of a 0.0000000001 risk factor then he is on a complete loser. What he is trying to say is that if a B737 were to lose a wing on take-off, then the situation would not be recoverable but should be.
Get a life, that's the way the cookie crumbles.
P.S. The last time I went to Francistown was from Matsapa. WANELA were flying DC-3s and DC-4s. Shortly afterwards, someone filled one of the DC-4s with AVTUR (JET A1) instead of AVTAG (AVGAS). I think they were all killed.
So maybe, instead of making aeroplanes 100% safe, you should concentrate on the 50/50 situations like putting the correct fuel into your aeroplane in the first place?
Last edited by JW411; 25th Nov 2010 at 15:28.
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It seems to be something with the older guys, who I guess after flying for many years, have the god complex about them.
I have nothing but respect for the older guys that have had their licences for so long that the number on the card is 0000002. I do my best to learn as much as I can from them. Case in point with abukaboy just sharing some good advice.
But there is a point where you can stow the attitude.
The point I am trying to make is the fact that this is a KNOWN problem. I don't recall hearing about a 737 wing falling off. Do you?
It the problem is as simple as grease. Why can they not design a safegaurd against it? Is prevention better than cure?
Don't even get me started on africa. Prevention is definately better than cure here....
I have nothing but respect for the older guys that have had their licences for so long that the number on the card is 0000002. I do my best to learn as much as I can from them. Case in point with abukaboy just sharing some good advice.
But there is a point where you can stow the attitude.
The point I am trying to make is the fact that this is a KNOWN problem. I don't recall hearing about a 737 wing falling off. Do you?
It the problem is as simple as grease. Why can they not design a safegaurd against it? Is prevention better than cure?
Don't even get me started on africa. Prevention is definately better than cure here....
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lilflyboy262 wrote:
Performance 'A' defines the lowest Acceleration Height as being 400ft AGL.
For a number of reasons, most large jet operators (typically) nominate lowest Acceleration Heights of 800ft, or 1000ft, or 1500ft AGL.
Most jet aircraft types have flap/slat asymmetry detection & protection systems. In the event that, when commanding the flaps to move from one position to the next, where an asymmetry is encountered during that movement, the system should stop all movement at (or very close to) the position where the asymmetry was detected; thus leaving the aircraft in a predominantly neutral position (wrt any tendency to roll, due to unbalanced aerodynamics).
Now in the event that you 1) have an asymmetry and 2) the asymmetry detection system also fails, what will then happen is that part of the flaps/slats system will continue to move to the commanded position, whilst some other part remains in a stuck position. With unbalanced aerodynamic forces, there will certainly be some tendency for the aircraft to roll, but not so much that it can't be counteracted with either aileron or rudder.
The key here is that the flaps are normally moved in a progressive manner and that should allow plenty of opportunity to both detect & deal with any asymmetry that is not detected and locked out by a (failed) flap asymmetry detection system.
And it somewhat goes without saying that the flight crew need to be vigilant for potential malfunctions when making changes to an aircraft's configuration.
lilflyboy262, yes, with an asymmetry there will be some tendency to roll, but it is unlikely to be some sort of flick-roll and therein it is most unlikely that the aircraft will be "wanting to roll on to its back", (as you somewhat melodramatically put it! ). At its very worst you'd need both of the aforementioned failures, whilst continuing to command an ever increasing asymmetric condition via the flap lever, and then do nothing about it (which would be a pretty outrageous set of circumstances, imho ).
Scenario 2. Im unfamiliar with that aircraft, so do not know if there are failsafes with how the flaps deploy, or what settings they use on take-off. So the pilots are low to the ground just after take off, through 300ft, captian calls for flaps to be retracted. One goes up. One stays down. Next moment we have assymetric flaps and the plane is wanting to roll onto its back.
For a number of reasons, most large jet operators (typically) nominate lowest Acceleration Heights of 800ft, or 1000ft, or 1500ft AGL.
Most jet aircraft types have flap/slat asymmetry detection & protection systems. In the event that, when commanding the flaps to move from one position to the next, where an asymmetry is encountered during that movement, the system should stop all movement at (or very close to) the position where the asymmetry was detected; thus leaving the aircraft in a predominantly neutral position (wrt any tendency to roll, due to unbalanced aerodynamics).
Now in the event that you 1) have an asymmetry and 2) the asymmetry detection system also fails, what will then happen is that part of the flaps/slats system will continue to move to the commanded position, whilst some other part remains in a stuck position. With unbalanced aerodynamic forces, there will certainly be some tendency for the aircraft to roll, but not so much that it can't be counteracted with either aileron or rudder.
The key here is that the flaps are normally moved in a progressive manner and that should allow plenty of opportunity to both detect & deal with any asymmetry that is not detected and locked out by a (failed) flap asymmetry detection system.
And it somewhat goes without saying that the flight crew need to be vigilant for potential malfunctions when making changes to an aircraft's configuration.
lilflyboy262, yes, with an asymmetry there will be some tendency to roll, but it is unlikely to be some sort of flick-roll and therein it is most unlikely that the aircraft will be "wanting to roll on to its back", (as you somewhat melodramatically put it! ). At its very worst you'd need both of the aforementioned failures, whilst continuing to command an ever increasing asymmetric condition via the flap lever, and then do nothing about it (which would be a pretty outrageous set of circumstances, imho ).
Last edited by CrashDive; 26th Nov 2010 at 02:38. Reason: typo + clarification
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Thanks for that 
I have had assymetric before. I guess the fact that it had barn doors for flaps may have made a difference but it wanted to roll pretty quick. That was going from 40 degrees to 18.
Not something that I would want to experience in IMC thats for sure.
I have had assymetric before. I guess the fact that it had barn doors for flaps may have made a difference but it wanted to roll pretty quick. That was going from 40 degrees to 18.
Not something that I would want to experience in IMC thats for sure.
