A320 - LGCIU 1 Elec Supply
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A320 - LGCIU 1 Elec Supply
Hi guys,
Bit of an odd one, but came up after a discussion with a skipper.
As we know, if you have a LGCIU 1 + 2 fault, you MIGHT still get some indications on the LG control panel of LGCIU1 is electrically supplied.
My question, is there anyway (without putting the gear down..) of telling if LGCIU1 is actually electrically supplied or not?
Looking forward to the abuse (and helpful answers)
Bit of an odd one, but came up after a discussion with a skipper.
As we know, if you have a LGCIU 1 + 2 fault, you MIGHT still get some indications on the LG control panel of LGCIU1 is electrically supplied.
My question, is there anyway (without putting the gear down..) of telling if LGCIU1 is actually electrically supplied or not?
Looking forward to the abuse (and helpful answers)
On the A330 there are 3 sets of downlock proximity sensors on each gear, LGCIU 1+2 and an independent system.
If LGCIU 1+2 fail you will still get the Landing Gear lights on the centre instrument panel from the independent sensors which operate via LGCIU 1 ( yes even if LGCIU 1 is broken and de-powered the independent still works )
I would think the 320 would be similar.
If LGCIU 1+2 fail you will still get the Landing Gear lights on the centre instrument panel from the independent sensors which operate via LGCIU 1 ( yes even if LGCIU 1 is broken and de-powered the independent still works )
I would think the 320 would be similar.
Last edited by nitpicker330; 9th Jul 2012 at 11:29.
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Independent sensor is such, it's a wired independent discreet signal from the prox sensor to the instrument panel through the box.
Single Ailse relies on LGCIU 1 for the panel indication. Hence this box is a no dispatch as per MEL.
A lights indication that is dispatchable with the same philosophy is a BSCU channel A inop, if that has crapped out you do not get the Autobrake indication lights, only the ECAM wheels page indication.
LGCIU 1 & 2 Fault i doubt any indication. Wheels page may have clue bar trying an extension. If both are dead I gather your QRH will be a Gravity Extension.
Single Ailse relies on LGCIU 1 for the panel indication. Hence this box is a no dispatch as per MEL.
A lights indication that is dispatchable with the same philosophy is a BSCU channel A inop, if that has crapped out you do not get the Autobrake indication lights, only the ECAM wheels page indication.
LGCIU 1 & 2 Fault i doubt any indication. Wheels page may have clue bar trying an extension. If both are dead I gather your QRH will be a Gravity Extension.
Last edited by Beeline; 9th Jul 2012 at 16:59.
Correct, the left triangle is LGCIU 1 the right triangle is LGCIU 2
Just did it in the Sim a month or so ago.
We had Both LGCIU's failed.
Gravity gear extn, then we got the centre panel 3 Green triangles ok.
Gear page showed nothing, as expected.
Just did it in the Sim a month or so ago.
We had Both LGCIU's failed.
Gravity gear extn, then we got the centre panel 3 Green triangles ok.
Gear page showed nothing, as expected.
Last edited by nitpicker330; 10th Jul 2012 at 06:01.
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Yup but in the 320 you'll only get the greens on the control panel if LGCIU1 is electrially supplied..
Hence my question if there is any way to tell prior to dumping the gear.
Thanks for input anyway
Hence my question if there is any way to tell prior to dumping the gear.
Thanks for input anyway
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A320 is different as it does not have independent sensors like the 330/340.
If LGCIU 1 is not electrically supplied it will NOT indicate any lights on the panel, it is the only LGCIU hardwired to that panel and is therefore a non dispatch. If the LGCIU developed a fault not related to its power supply the LGCIU 2 can still use the channel to illuminate the lights, but THROUGH LGCIU 1 being supplied by the DC ESS bus. Trip the CB no panel lights!
The only way of telling that your LGCIU 1 has died is by your ECAM L1/2 caution telling you as such and the amber xx where your triangle used to be on the ECAM wheels page.
LGCIU 1 and 2 fault means no indication or control/monitioring hence gravity extension.
If LGCIU 1 is not electrically supplied it will NOT indicate any lights on the panel, it is the only LGCIU hardwired to that panel and is therefore a non dispatch. If the LGCIU developed a fault not related to its power supply the LGCIU 2 can still use the channel to illuminate the lights, but THROUGH LGCIU 1 being supplied by the DC ESS bus. Trip the CB no panel lights!
The only way of telling that your LGCIU 1 has died is by your ECAM L1/2 caution telling you as such and the amber xx where your triangle used to be on the ECAM wheels page.
LGCIU 1 and 2 fault means no indication or control/monitioring hence gravity extension.
Last edited by Beeline; 10th Jul 2012 at 15:52.
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Agree, apart from Lgciu 1&2 fault giving no indication.
The checklists and FCOM point out that even if both have failed, you MAY still get an indication if LgCIU1 is elec supplied.
So you can have a dual LGCIU failure with gear indications (even of ecam says both have failed on wheel page) but my reckoning is the until you dump the gear you won't know if you have indications remaining so you're going to be preparing the cabin for an emergency landing anyway as otherwise they won't have much time.
Thoughts?
The checklists and FCOM point out that even if both have failed, you MAY still get an indication if LgCIU1 is elec supplied.
So you can have a dual LGCIU failure with gear indications (even of ecam says both have failed on wheel page) but my reckoning is the until you dump the gear you won't know if you have indications remaining so you're going to be preparing the cabin for an emergency landing anyway as otherwise they won't have much time.
Thoughts?
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xx instead of left and right triangles on your wheel page across the board and LGCIU 1+2 fault on the EWD will show a dual LGCIU failure.
if you have an LGCIU internal 1 fault but with LGCIU 2 still in operation, as long as LGCIU 1 has power LGCIU 2 can send the information through the box, hence indication as they cross-talk.
If LGCIU 1 has detonated in the rack what is probably more than likely than an internal card fault there is no chance of any indication as it is now not powered.
LGCIU 1 + 2 fault means you should not trust any information these boxes are giving you only the amber crosses saying they are dead hence why Airbus ask you to gravity extend.
You may have the downlock sensors available that might get through the wreckage of the boxes but as previously said they are more than likely smoking in the MEC.
if you have an LGCIU internal 1 fault but with LGCIU 2 still in operation, as long as LGCIU 1 has power LGCIU 2 can send the information through the box, hence indication as they cross-talk.
If LGCIU 1 has detonated in the rack what is probably more than likely than an internal card fault there is no chance of any indication as it is now not powered.
LGCIU 1 + 2 fault means you should not trust any information these boxes are giving you only the amber crosses saying they are dead hence why Airbus ask you to gravity extend.
You may have the downlock sensors available that might get through the wreckage of the boxes but as previously said they are more than likely smoking in the MEC.
Last edited by Beeline; 11th Jul 2012 at 18:01.
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Beeline,
Thanks for input but still disagree.
FCOm pro - Abn - LGCIU 1 & 2 fault..
Level 2 info.. "normal landing gear control and position indications are lost. LDG GEAR lights on LDG GEAR control panel remain available if LGCIU 1 is electrically supplies".
QRH 32.03 L/G Gravity Extension
Note 2: "in event of gravity extension caused by failure of both LGCius, landing gear position indications on ECAM are lost. LDG GEAR light on LDG GEAR control panel remain available if LGCIU1 electrically supplies"
Thanks for input but still disagree.
FCOm pro - Abn - LGCIU 1 & 2 fault..
Level 2 info.. "normal landing gear control and position indications are lost. LDG GEAR lights on LDG GEAR control panel remain available if LGCIU 1 is electrically supplies".
QRH 32.03 L/G Gravity Extension
Note 2: "in event of gravity extension caused by failure of both LGCius, landing gear position indications on ECAM are lost. LDG GEAR light on LDG GEAR control panel remain available if LGCIU1 electrically supplies"
In the sim LGCIU 1 + 2 = No indications on ECAM or Landing gear control panel that the gear is down. All you have is noise and pitch and power to decide if the gear has come down. This is because the sim assumes LGCIU 1 is totally dead if you have LGCIU fault.
Lots of people seem to go around and then complete the landing with unsafe gear QRH. This is totally pointless as if you have completed the gravity gear extension and the aircraft performance tells you the gear is extended and there is no asymmetric handling issues then you are good to land. You are also expecting not to see any gear indications. It would be prudent to brief this first before completing the approach and then trying to decide if the gear has gone down and then going around.
Lots of people seem to go around and then complete the landing with unsafe gear QRH. This is totally pointless as if you have completed the gravity gear extension and the aircraft performance tells you the gear is extended and there is no asymmetric handling issues then you are good to land. You are also expecting not to see any gear indications. It would be prudent to brief this first before completing the approach and then trying to decide if the gear has gone down and then going around.
Last edited by Pizza Express; 12th Jul 2012 at 08:21.
Wow that's brave of you.
Hoping the springs, gravity and wind lock the gear down.
Because the Gear Doors open and the drag and wind noise increase it DOES NOT CONFIRM THE GEAR ARE DOWN AND LOCKED.
Running the Emer LDG checklist and preparing the Cabin is the right thing to do. Anything less is negligent.
Hoping the springs, gravity and wind lock the gear down.
Because the Gear Doors open and the drag and wind noise increase it DOES NOT CONFIRM THE GEAR ARE DOWN AND LOCKED.
Running the Emer LDG checklist and preparing the Cabin is the right thing to do. Anything less is negligent.
Last edited by nitpicker330; 12th Jul 2012 at 10:33.
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Take it from someone who pulls them out of the rack. The message LGCIU 1+2 means two dead LGCIUs.
I am not ruling out a signal could not get through if the fault is an internal card failure but again more than likely it will be completely dead no indication, you can't get the lights if no power or if the downlock sensors can't get the message through.
Your FCOM will cover all the angles and scenarios, I am saying the practical reasoning of this fault.
Beeline out
I am not ruling out a signal could not get through if the fault is an internal card failure but again more than likely it will be completely dead no indication, you can't get the lights if no power or if the downlock sensors can't get the message through.
Your FCOM will cover all the angles and scenarios, I am saying the practical reasoning of this fault.
Beeline out
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Is that the case nitpicker... Please bear in mind that the company myself i_like_tea and pizza express work for expressly forbid flyby's.
Which items are you going to perform from the Landing with abnormal L/G QRH?
- Nose or Main Gear?
- if Main gear, one or both?
Will you reset the handcrank system which the abnormal l/g QRH tells you to do baring in mind that the gravity gear extend checklist says:
How will you determine if the gravity extend was a success Or failure? Using the belts and braces method of doing the abnormal l/g procedure might just get you into the position of an unlocked l/g.
Are you going to turn the antiskid nosewheelsteering OFF (our aircraft have NWS on yellow system so it remains functional after gravity extend) and go to alternate braking 1000psi max while loosing directional control capability?
Please consider that with LGCIU 1+2 Fault you will have NO reversers! In addition you will have no wing anti-ice which could lead to ice accretion which will increase your approach speed.
Which actions will you perform in the flare? Nose, 1 main gear, both main gear?
Bear in mind that they all tell you to shut engines at a different time, from in the flare to just before nose touchdown.
Do you want to create a stopping problem???
I don't know the answer... But nitpicking (no pun intended) items from checklists could leave you out in the cold... The system and checklists are not very well designed at all, A330 system seems much better.
I would prepare the cabin for an emergency landing though.
Which items are you going to perform from the Landing with abnormal L/G QRH?
- Nose or Main Gear?
- if Main gear, one or both?
Will you reset the handcrank system which the abnormal l/g QRH tells you to do baring in mind that the gravity gear extend checklist says:
Do not reset the free-fall system: This will avoid such undesirable effects as further loss of fluid, in the event of a leak, or possible landing gear unlocking, in the event of a gear selector valve jamming in the UP position.
Are you going to turn the antiskid nosewheelsteering OFF (our aircraft have NWS on yellow system so it remains functional after gravity extend) and go to alternate braking 1000psi max while loosing directional control capability?
Please consider that with LGCIU 1+2 Fault you will have NO reversers! In addition you will have no wing anti-ice which could lead to ice accretion which will increase your approach speed.
Which actions will you perform in the flare? Nose, 1 main gear, both main gear?
Bear in mind that they all tell you to shut engines at a different time, from in the flare to just before nose touchdown.
Do you want to create a stopping problem???
I don't know the answer... But nitpicking (no pun intended) items from checklists could leave you out in the cold... The system and checklists are not very well designed at all, A330 system seems much better.
I would prepare the cabin for an emergency landing though.
Last edited by 737Jock; 12th Jul 2012 at 11:17.
I was suggesting that to just land "guessing" the wheels where down without some sort of preperation was stupid and negligent.
Plan for the worst and hope for the best.
Oh and I said "Emergency Landing checklist"
Plan for the worst and hope for the best.
Oh and I said "Emergency Landing checklist"
Last edited by nitpicker330; 12th Jul 2012 at 11:52.
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Thanks Beeline, I appreciate the input and take heed for your knowledge!
Good to know that about the Sim, least in rules out the question!
Thanks all.
In the sim LGCIU 1 + 2 = No indications on ECAM or Landing gear control panel that the gear is down. All you have is noise and pitch and power to decide if the gear has come down. This is because the sim assumes LGCIU 1 is totally dead if you have LGCIU fault.
Thanks all.
