Air India Airbus 319 Suspected Triple Hydraulic Failure
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THS (trimmable horizontal stabilizer) through trim wheel,and rudder mechanical backup are available in case of All hydraulic failure
but hopefully you are NOT in a LH seat of an airbus...
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Landing with 3 hydraulic systems failure was incorporated in our recurrent training program in my company after the DHL Baghdad incident. Since we were/are flying in sensitive areas (Irak, Kabul, Sudan, Yemen), the probability of being hit by a missile is greater than if you fly let's say in northern Canada. I and my colleagues have landed numerous times on A320, B767 and E190 (in the simulator of course) with the 3 hydraulic systems failure. After a little bit of practice, any pilot with a minimum of coordination can land on the pavement. So CaptProp, if one day you fly with a current or ex Gulfair pilot in the flight deck and we encounter this failure, while you kiss your arse goodbye, we'll be trying to land the airplane on the numbers.
Did you try doing this in any sort of low-ish visibility? With any cross winds/gusty winds? From cruise down to landing? Prolonged flight in IMC? Actually flying an approach of some kind?
Or was it just from 10 nm final lined up with the "pavement" and CAVOK, in flight freeze and "Ok guys, are you ready? Then I'll un-freeze you and off you go lads!" ??
I would give the average crew 1 in 1000 to make it. On a good day.
Not referring to Yo767 here, but there are a lot of people around here, some even claiming to fly / know the airbus, making the most ridiculous comments about the airbus and its systems.
To clarify some things....
- Flight controls are Electrically-controlled and Hydraulically-activated.
- If you lose ALL electricity "MAN PITCH TRIM ONLY" will be displayed on the PFD and manual pitch trim (Mechanical control) of the THS is possible through the pitch trim wheel. This is called "Mechanical Backup" and has nothing to do with HYD systems.
- The Stabilizer is activated by Green or Yellow HYD pressure. If you have no HYD pressure at all, you will have no control of the THS. Referring to mechanical control of the THS there is a note in the FCOM stating "This function is inoperative, when the green or yellow hydraulic system is not pressurized"
- Rudder pedals gives the pilot MECHANICAL control of the rudder but the rudder is HYDRAULICALLY actuated via three independent hydraulic servojacks. In other words, if you have no HYD pressure you can not actuate the rudder.
CaptainProp has it right on the money. I did my original training on the A320 with an Airbus test pilot some 20 years ago and he always made the point that without hydraulics you are screwed because the flight controls will not move. Although we did carry out approaches to land in the simulator there in mechanical back-up, thats with hydraulics but no Flight Control Computers, and it was doable, they emphasised that mechanical back-up was there to give time to recover at least one FCC. There are way to many armchair pilots on here!
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Tried this in the Sim a few years back. Managed to 'drain' all three systems to instigate the failure AFTER putting the gear down at about 15,000 feet.
As has been correctly stated before ALL flight controls are lost and the only means of flying the beastie is by thrust and aysemetric thrust.
A good brief (probably not going to happen if, God forbid, it ever happened for real!) and teamwork got us on the ground. It did take a few attempts mind you, something that real life wouldn't give you but, after a few tries it got progressivly easier to put it down on the airfield.
Not a problem though as, according to Toulouse, it can't ever, never, never, ever happen!
As has been correctly stated before ALL flight controls are lost and the only means of flying the beastie is by thrust and aysemetric thrust.
A good brief (probably not going to happen if, God forbid, it ever happened for real!) and teamwork got us on the ground. It did take a few attempts mind you, something that real life wouldn't give you but, after a few tries it got progressivly easier to put it down on the airfield.
Not a problem though as, according to Toulouse, it can't ever, never, never, ever happen!
One should be very wary of trying odd things in the simulator, such as no hydraulics flying. What the simulator does may have no resemblance to what the aircraft will do because no flight data was collected during the flight testing in order to programme the simulator correctly. The same applies to recoveries from unusual attitudes. Some trainers seem to think that they can place the aircraft in all sorts of weird positions and that the simulator will react like to aircraft. Not true, again because no data was gather during testing for these extreme situations and the simulator may not reflect what the aircraft will do. So be careful and don't be succored into thinking that if you can handle these things in the Simulator you will be OK in the aircraft. It just might bite you!
No, they can be mechanically controlled, however they are hydraulically actuated. Have a look at the control schematic in the QRH, you can see the mechanical control connects to the hydraulic actuators.
This mechanical control is in place for the failure of the flight control computers. Electric control provided by the PRIM/SEC/FAC to the actuators, the mechanical control backs them up, it is designed to give enough control to get a computer reset and back online, it is not really designed for approach and landing as it is often misunderstood. It is not for a triple hydraulic system failure.
All in FCOM 1.
The A380 can be controlled wih the loss of the aircraft hydraulic system, as they have different actuators that have their own internal backup hydraulic system or electric motor to move the control surface.
This mechanical control is in place for the failure of the flight control computers. Electric control provided by the PRIM/SEC/FAC to the actuators, the mechanical control backs them up, it is designed to give enough control to get a computer reset and back online, it is not really designed for approach and landing as it is often misunderstood. It is not for a triple hydraulic system failure.
All in FCOM 1.
The A380 can be controlled wih the loss of the aircraft hydraulic system, as they have different actuators that have their own internal backup hydraulic system or electric motor to move the control surface.
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As has been correctly stated before ALL flight controls are lost and the only means of flying the beastie is by thrust and aysemetric thrust.
Ummmmm, well, something is deeply wrong here as every single trainer I have flown with has given me the perception that IT IS possible to control the aircraft with pitch trim and rudders in the event of a TRIPLE HYD failure.
Last edited by Superpilot; 14th Jul 2012 at 15:42.
Ummmmm, well, something is deeply wrong here as every single trainer I have flown with has given me the perception that IT IS possible to control the aircraft with pitch trim and rudders in the event of a TRIPLE HYD failure.
Last edited by Superpilot; 14th Jul 2012 at 15:42.
Heaven help us if you are actually flying the thing on the line somewhere and believe this!
What other gaping holes exist in your knowledge?
Just think about this logically.
No hydraulics =
Last edited by MACH082; 14th Jul 2012 at 08:04.
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The quality of airbus trainers could be another interesting thread. When I was doing my TRI in Germany, we were 5 captains. I was the only one who knew, that 3ple hydraulic means mechanical back up.
In our last QRH Airbus in its infinitive wisdom even took away the pitch and power setting for 3 degree glide path. The QRH tells you also to first level the wings in case of a stall and than recover from the stall.
I still think airbus is a superior airplane that produces inferior pilots. Boeing is the other way around. By the way I am an airbus guy, wishing to be a Boeing guy. Cannot deal with the training stupidity anymore. I see many guys in the sim with over 6000 hrs on airbus and they cannot fly basic pitch and power in this easy to fly airplane. When I train Boeing guys, it is not a problem after few minutes of getting used to the plane.
I am not sure if to blame the plane or airbus philosophy of training for this mess, but I suspect the second. How else you could have 3 pilots sitting in a stalled airplane for 3 minutes falling from over 30000 feet and not having a clue what is going on?
In our last QRH Airbus in its infinitive wisdom even took away the pitch and power setting for 3 degree glide path. The QRH tells you also to first level the wings in case of a stall and than recover from the stall.
I still think airbus is a superior airplane that produces inferior pilots. Boeing is the other way around. By the way I am an airbus guy, wishing to be a Boeing guy. Cannot deal with the training stupidity anymore. I see many guys in the sim with over 6000 hrs on airbus and they cannot fly basic pitch and power in this easy to fly airplane. When I train Boeing guys, it is not a problem after few minutes of getting used to the plane.
I am not sure if to blame the plane or airbus philosophy of training for this mess, but I suspect the second. How else you could have 3 pilots sitting in a stalled airplane for 3 minutes falling from over 30000 feet and not having a clue what is going on?
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you are absolutely right. Many people misunderstand mechanical back up. It is not a back up for hydraulics but electrics. since this is FBW everythig is signalled electrically and you need something that moves without electrics for short time atleast.
Last edited by vilas; 14th Jul 2012 at 09:09.
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The end result would probably be the same.
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@ PBY
Was that a typo, or just me being too thick ( has happened before!
) to understand what you wrote?
From my previous post
Hydraulic failure(-s) has nothing to do with mechanical backup, electrical failure does.
He/she would know what was NOT an option anymore. Is it all of a sudden acceptable to have pilots NOT knowing the systems of the aircraft they fly? What else does he/she not know? What else are these "instructors" telling crew they can or can't do with this aircraft?
I've seen a very experienced airbus crew opening the X FEED valve when getting a fuel imbalance advisory 15 min after having an engine failure with damage. Pumped fuel over board and ran out of fuel on short final. 30+ years of airbus experience between the crew.
Another crew were getting a low on fuel with dual HYD failures and briefed that "Weather is not great so we will give it one go. If we can't get down we'll continue to our alternate" Checked fuel on FMS and were "happy" with their plan. Go around followed some minutes later by "Jeeesus, we are burning a lot of fuel....." Flying to their alternate with gear down and flaps jammed was not something they had calculated with... This was a very inexperienced crew though so hopefully it was a good learning experience for them.
I am a relatively speaking inexperienced simulator instructor so I am sure there are people out there who have seen many more of these mistakes, mistakes that should not really happen if you know your aircraft systems well.
I also have to add that most of my instructors over the years have been very good and personally I have no complaints. Some stories here makes you wonder though.....
....I was the only one who knew, that 3ple hydraulic means mechanical back up.
) to understand what you wrote? From my previous post
- Flight controls are Electrically-controlled and Hydraulically-activated.
- If you lose ALL electricity "MAN PITCH TRIM ONLY" will be displayed on the PFD and manual pitch trim (Mechanical control) of the THS is possible through the pitch trim wheel. This is called "Mechanical Backup" and has nothing to do with HYD systems.
- If you lose ALL electricity "MAN PITCH TRIM ONLY" will be displayed on the PFD and manual pitch trim (Mechanical control) of the THS is possible through the pitch trim wheel. This is called "Mechanical Backup" and has nothing to do with HYD systems.
Why? What would change if he believe it or not in case of triple hydraulic failure?
I've seen a very experienced airbus crew opening the X FEED valve when getting a fuel imbalance advisory 15 min after having an engine failure with damage. Pumped fuel over board and ran out of fuel on short final. 30+ years of airbus experience between the crew.
Another crew were getting a low on fuel with dual HYD failures and briefed that "Weather is not great so we will give it one go. If we can't get down we'll continue to our alternate" Checked fuel on FMS and were "happy" with their plan. Go around followed some minutes later by "Jeeesus, we are burning a lot of fuel....." Flying to their alternate with gear down and flaps jammed was not something they had calculated with... This was a very inexperienced crew though so hopefully it was a good learning experience for them.
I am a relatively speaking inexperienced simulator instructor so I am sure there are people out there who have seen many more of these mistakes, mistakes that should not really happen if you know your aircraft systems well.
I also have to add that most of my instructors over the years have been very good and personally I have no complaints. Some stories here makes you wonder though.....
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I'm deeply shocked. Reading all these conflicting views it seems that at least some current A320/A330 pilots wouldn't be well equipped to handle a serious FCS issue. I hope someone from CAA/FAA reads this thread and takes some action. Meanwhile lets all cross our fingers and toes next time we fly as pax or FC.
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When I was doing my TRI in Germany, we were 5 captains. I was the only one who knew, that 3ple hydraulic means mechanical back up.
The flight controls are electrically or mechanically controlled as follows :
Pitch axis
Elevator = Electrical
Stabilizer = Electrical for normal or alternate control. Mechanical for manual trim
control
Roll axis
Ailerons = Electrical
Spoilers = Electrical
Yaw axis
Rudder = Mechanical, however control for yaw damping, turn coordination and trim
is electrical.
Speed brakes
Speed brakes = Electrical
Note: All surfaces are hydraulically actuated.
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FCOM DSC 27-10-20:
FCOM 27-20-20:
FCOM 27-10-10:
But still ALWAYS hydraulically activated.
Thrust is the only method.
Mechanical control of the THS is available from the pitch trim wheel at any time, if either the green or yellow hydraulic system is functioning. Mechanical control from the pitch trim wheel has priority over electrical control.
Mechanical backup enables the pilot to control the aircraft during a temporary complete loss of electrical power. He does this in pitch by manually applying trim to the THS. The PFDs display “MAN PITCH TRIM ONLY” in red.
Flight control surfaces are all : ‐ Electrically-controlled, and ‐ Hydraulically-activated. The stabilizer and rudder can also be mechanically-controlled.
Thrust is the only method.
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Soon we should have everbody convinced that the FCOM/QRH is not wrong, what we are saying is no windup, and then we can move on to next system. Perhaps we should apply for TRTO approval for on-line airbus tech courses?! 
Last edited by CaptainProp; 14th Jul 2012 at 15:35.
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He/she would know what was NOT an option anymore. Is it all of a sudden acceptable to have pilots NOT knowing the systems of the aircraft they fly? What else does he/she not know? What else are these "instructors" telling crew they can or can't do with this aircraft?
1. loss of 3 hyd., knows he is screwed, gives up and dies.
2. loss of 3 hyd., doesn't know he's screwed, tries to do something, finds out he can't, gives up and dies.
No, it is not acceptable not knowing the systems(is not sudden, is quite a while that training moved from know all to know what is needed.) but him not knowing the above does not mean he has other holes in his knowledge, as knowing the above does not mean one might not lack somewhere else.
I like to believe I know everything about my aircraft, but I know I do not and I keep learning.
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Mechanical Back-up is a simple concept for a fully trained A320 crew. Those who say there is mechanical back-up in the event of total hydraulic failure might be trainees trying to understand their hydraulic studies.
Might as well get it wrong on pprune rather than in sim check.
Might as well get it wrong on pprune rather than in sim check.
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Captain Prop is correct if you check the Airbus FCOM.
If you lose all electical control of the flight control system then the THS and rudder still have mechanical control .But lose all 3 hydraulic systems and all actuation of every flight control surface is lost.Only engine control would be available to control pitch and yawing but that's assuming they still have electrical control available as the thrust levers have no mechanical connection to the engines.
If you lose all electical control of the flight control system then the THS and rudder still have mechanical control .But lose all 3 hydraulic systems and all actuation of every flight control surface is lost.Only engine control would be available to control pitch and yawing but that's assuming they still have electrical control available as the thrust levers have no mechanical connection to the engines.
