Dual fmc failure
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if you don't have an FMC to generate an FMC position from the IRSs and the GPS then you cannot be RNP-10.
Yes you can be RNP-10. In the following cases:
6.2 hours after placing IRU in navigation mode (pure inertial), or
5.9 hours after the last automatic DME/DME position update, or
5.7 hours after the last automatic VOR/DME position update.
The FMS continuosly monitors input from the available naviagtion sensors (radios, IRUs, and GNS) to compute a position and actual navigation performance "ANP" value in units of nautical miles. The FMS RNP function is used as a integrrity monitor for airplane position.
If the plane is certificated to fly in RNP-10 airspace then, you can fly without GPS for a flight time not to exceed:
6.2 hrs.
5.9 hrs.
5.7 hrs.
Yes you can be RNP-10. In the following cases:
6.2 hours after placing IRU in navigation mode (pure inertial), or
5.9 hours after the last automatic DME/DME position update, or
5.7 hours after the last automatic VOR/DME position update.
The FMS continuosly monitors input from the available naviagtion sensors (radios, IRUs, and GNS) to compute a position and actual navigation performance "ANP" value in units of nautical miles. The FMS RNP function is used as a integrrity monitor for airplane position.
If the plane is certificated to fly in RNP-10 airspace then, you can fly without GPS for a flight time not to exceed:
6.2 hrs.
5.9 hrs.
5.7 hrs.
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Well, on the bus, you will lose A/P, FD and A/THR. So nope, youīre not RVSM.
Itīs not a mayday, but a few unable RVSM and RNAV are mandatory. Just fly it manually, use stand by nav, and fly the acft as a conventional one, while trying to recover at least one FMGS doing resets. And of course, ask for vectors if you are under radar control.
Itīs actually good on long flights to practice a little bit with the VORīs, knowing what radial are you in, how will you get in a holding from X radial, how will you intercept that other radial outbound...It really helps.
Nice to have been a FI before the bus
Itīs not a mayday, but a few unable RVSM and RNAV are mandatory. Just fly it manually, use stand by nav, and fly the acft as a conventional one, while trying to recover at least one FMGS doing resets. And of course, ask for vectors if you are under radar control.
Itīs actually good on long flights to practice a little bit with the VORīs, knowing what radial are you in, how will you get in a holding from X radial, how will you intercept that other radial outbound...It really helps.
Nice to have been a FI before the bus
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How can you navigate with reference to IRS if you don't have an FMS?
You need not only position accuracy but also flight technical error accuracy. Unless your avionics can bypass the FMC and display deviation from IRS(INS) DTRK you cannot fly RNP-10 without an FMS.
You need not only position accuracy but also flight technical error accuracy. Unless your avionics can bypass the FMC and display deviation from IRS(INS) DTRK you cannot fly RNP-10 without an FMS.
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The CDU replaces the FMC for reference and uses Alternate navigation. It is more cumbersome but we still have navigation capability. Sort of like in the old INS days without a database where any waypoints are entered by lat/long. Other restrictions apply as well but we can continue to navigate.
Last edited by JammedStab; 1st Jul 2016 at 01:53.
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Of course aircraft type is crucial here.
For info on B757/767/787/777/747 you still have full CAT3B autoland capability with total FMC failure !
RVSM is not affected by this either.
MNPS and oceanic ops are not approved without at least 1 FMC so would need your head examining to carry on and enter that airspace like this. Of course if already in then crack on as best you can.
BRNAV in europe which is RNP5 so thats gone with the FMC's.
The 787 has 3 FMC's.....so job done
For info on B757/767/787/777/747 you still have full CAT3B autoland capability with total FMC failure !
RVSM is not affected by this either.
MNPS and oceanic ops are not approved without at least 1 FMC so would need your head examining to carry on and enter that airspace like this. Of course if already in then crack on as best you can.
BRNAV in europe which is RNP5 so thats gone with the FMC's.
The 787 has 3 FMC's.....so job done
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HPbleed
Can`t you use the VOR(s) "wassup doc?" If you are in RVSM can`t you request a non-RVSM and maybe get/need a re-release or am I talking out of my NDB - which you can also use if there are any left. It means you are now driving but you can stay in Selected mode and autopilot and well, easy life, you have just got to get on with the nav without any delay. You have your charts. Just do some work for a change.
>>>@pantload - you`re silly.
and, and, if you are truuuuuly lazy you can ask for vectors (if they can see you) and get them the ATC boys to do some work for a change. Seriously, though in reality everybody will be lending a hand, some will offer, others will have to be delegated, all in all the outcome will be brill - just trying to figure out the ILS bit - do we have an ILS? If not can we use VOR + DME - if no DME then find somebody who can a/. Navigate well and b/. can count.
Raw VOR with no dme in IMC would be interesting, kind of a bad weather circuit using a VOR - that`ll give aerodrome atc a run for their money - but hey there`s approach control, Approach Radar, life `aint so bad. the thing is you see - to go somewhere nice where they have such ATC facilities, like SRA and PAR with gorgeous bright runway lighting a nice set of ALSF-2 should be suffice and yummy vectors. Or, if you are too proud for vectors then QTE`s and QDM`s - being too proud for vectors though, is a bit like being too proud to accept Kate Upton`s invitation to dinner. Is it far to the sea? Are there mountains around? How about some high ground - this`d be interesting in MEX, but, but you can also use the AWR map mode . . thing . .mode, but if the FMGS is out then do we have AWR, must do . . except it, the awr display, lives on the screen and the screens may be out or the awr has its own dedicated screen. hmmm. You have to sort something out quick though you are travelling at 4.46 m/s which is shifting PDQ. A320. Ah, no a/p. . .well, thats no hardship in a bus which holds everything anyway.
@OCAMPO no, just close your eyes, delete the lot and it will all go away - not happening am afraid you actually have to deal with it - which means putting the chat up lines to the FA on hold and doing some real work, I know, I know, its a hard life sometimes . . . but best to be cuddly wuddly with the hostie at the end of the day and at the end of a long G&T rather than cuddling a freezing cold mountain now isn't it? so, the IRS, or INS in English, will still be working, giving nice things like, position and ground speed and wind.
While we are all here - they should spring this one on us in the sim, much more often, if necessary - it would make for a round-up to the day. Especially at the end of a successful session. After all, the proverbial always seems to hit the fan just when you are about to finish off your Mini Cheddars:/
but you can stay in Selected mode and autopilot and well, easy life, you have just got to get on with the nav without any delay. You have your charts. Just do some work for a change.>>>@pantload - you`re silly.
and, and, if you are truuuuuly lazy you can ask for vectors (if they can see you) and get them the ATC boys to do some work for a change. Seriously, though in reality everybody will be lending a hand, some will offer, others will have to be delegated, all in all the outcome will be brill - just trying to figure out the ILS bit - do we have an ILS? If not can we use VOR + DME - if no DME then find somebody who can a/. Navigate well and b/. can count.
Raw VOR with no dme in IMC would be interesting, kind of a bad weather circuit using a VOR - that`ll give aerodrome atc a run for their money - but hey there`s approach control, Approach Radar, life `aint so bad. the thing is you see - to go somewhere nice where they have such ATC facilities, like SRA and PAR with gorgeous bright runway lighting a nice set of ALSF-2 should be suffice and yummy vectors. Or, if you are too proud for vectors then QTE`s and QDM`s - being too proud for vectors though, is a bit like being too proud to accept Kate Upton`s invitation to dinner. Is it far to the sea? Are there mountains around? How about some high ground - this`d be interesting in MEX, but, but you can also use the AWR map mode . . thing . .mode, but if the FMGS is out then do we have AWR, must do . . except it, the awr display, lives on the screen and the screens may be out or the awr has its own dedicated screen. hmmm. You have to sort something out quick though you are travelling at 4.46 m/s which is shifting PDQ. A320. Ah, no a/p. . .well, thats no hardship in a bus which holds everything anyway.
@OCAMPO no, just close your eyes, delete the lot and it will all go away - not happening am afraid you actually have to deal with it - which means putting the chat up lines to the FA on hold and doing some real work, I know, I know, its a hard life sometimes . . . but best to be cuddly wuddly with the hostie at the end of the day and at the end of a long G&T rather than cuddling a freezing cold mountain now isn't it? so, the IRS, or INS in English, will still be working, giving nice things like, position and ground speed and wind.
While we are all here - they should spring this one on us in the sim, much more often, if necessary - it would make for a round-up to the day. Especially at the end of a successful session. After all, the proverbial always seems to hit the fan just when you are about to finish off your Mini Cheddars:/
Last edited by Natstrackalpha; 5th Nov 2015 at 12:33. Reason: Can`t type.
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Well, I guess if I had a simultaneous failure of two FMS' (assuming there were only two), and considering each FMS is usually (always?) powered by separate electrical buses, I'd want to know what else doesn't work. This would almost be an impossibility without other failures somewhere.
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Well, I guess if I had a simultaneous failure of two FMS' (assuming there were only two), and considering each FMS is usually (always?) powered by separate electrical buses, I'd want to know what else doesn't work. This would almost be an impossibility without other failures somewhere.
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Of course aircraft type is crucial here.
For info on B757/767/787/777/747 you still have full CAT3B autoland capability with total FMC failure !
RVSM is not affected by this either.
MNPS and oceanic ops are not approved without at least 1 FMC so would need your head examining to carry on and enter that airspace like this. Of course if already in then crack on as best you can.
BRNAV in europe which is RNP5 so thats gone with the FMC's.
The 787 has 3 FMC's.....so job done
For info on B757/767/787/777/747 you still have full CAT3B autoland capability with total FMC failure !
RVSM is not affected by this either.
MNPS and oceanic ops are not approved without at least 1 FMC so would need your head examining to carry on and enter that airspace like this. Of course if already in then crack on as best you can.
BRNAV in europe which is RNP5 so thats gone with the FMC's.
The 787 has 3 FMC's.....so job done
"N662US, a Boeing 747-400 aircraft operated by Delta Airlines as flight DAL167, had departed Seattle-Tacoma Intl, WA, (KSEA) en route to Tokyo/New Tokyo Intl, Japan (RJAA). Approximately 60 nautical miles south southwest of Tofino, BC the flight crew declared an emergency due to a dual Flight Management System (FMS) navigation equipment failure. The aircraft circled south of Vancouver Island for approximately one hour to dump fuel in order to be within its maximum landing weight limitation. The aircraft returned to KSEA and landed without further incident.
The operator’s maintenance determined that the FMS was faulty. The number 1 FMS was replaced and tested, and the aircraft was returned to service the following day."
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For info on B757/767/787/777/747 you still have full CAT3B autoland capability with total FMC failure !
In the 744 there will be no autothrottle, so no Cat 3 capability for most operators. In any case, it is not "full" Cat 3 capability.
As for DAL167, while it is POSSIBLE to continue from SEA-NRT with a dual FMS falure, I would not consider it smart. Pilot workload would be increased significantly, including a HUGE workload increase in the terminal area at the end of a long flight. With so little tolerance for deviation from the norm these days, returning to SEA was a good move.
Also, while it might not be a true "emergency" situation that had high risk to life & limb, declaring an emergency is often the only way to get priority handling so fuel dump and return can be accomplished.
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Not quite...
In the 744 there will be no autothrottle, so no Cat 3 capability for most operators. In any case, it is not "full" Cat 3 capability.
As for DAL167, while it is POSSIBLE to continue from SEA-NRT with a dual FMS falure, I would not consider it smart. Pilot workload would be increased significantly, including a HUGE workload increase in the terminal area at the end of a long flight. With so little tolerance for deviation from the norm these days, returning to SEA was a good move.
Also, while it might not be a true "emergency" situation that had high risk to life & limb, declaring an emergency is often the only way to get priority handling so fuel dump and return can be accomplished.
In the 744 there will be no autothrottle, so no Cat 3 capability for most operators. In any case, it is not "full" Cat 3 capability.
As for DAL167, while it is POSSIBLE to continue from SEA-NRT with a dual FMS falure, I would not consider it smart. Pilot workload would be increased significantly, including a HUGE workload increase in the terminal area at the end of a long flight. With so little tolerance for deviation from the norm these days, returning to SEA was a good move.
Also, while it might not be a true "emergency" situation that had high risk to life & limb, declaring an emergency is often the only way to get priority handling so fuel dump and return can be accomplished.
No A/T is no 3B, 3A is fine and it's still easier than flying the classic but less rewarding.
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Not quite...
In the 744 there will be no autothrottle, so no Cat 3 capability for most operators. In any case, it is not "full" Cat 3 capability.
As for DAL167, while it is POSSIBLE to continue from SEA-NRT with a dual FMS falure, I would not consider it smart. Pilot workload would be increased significantly, including a HUGE workload increase in the terminal area at the end of a long flight. With so little tolerance for deviation from the norm these days, returning to SEA was a good move.
Also, while it might not be a true "emergency" situation that had high risk to life & limb, declaring an emergency is often the only way to get priority handling so fuel dump and return can be accomplished.
In the 744 there will be no autothrottle, so no Cat 3 capability for most operators. In any case, it is not "full" Cat 3 capability.
As for DAL167, while it is POSSIBLE to continue from SEA-NRT with a dual FMS falure, I would not consider it smart. Pilot workload would be increased significantly, including a HUGE workload increase in the terminal area at the end of a long flight. With so little tolerance for deviation from the norm these days, returning to SEA was a good move.
Also, while it might not be a true "emergency" situation that had high risk to life & limb, declaring an emergency is often the only way to get priority handling so fuel dump and return can be accomplished.
But, it appears that oceanic airspace may not be allowed due to entry requirements of 1 FMC. (Please provide a link to show this). Would it make sense to consider a re-route further north onto a Russian Route in order to continue and perhaps refuel in Sapporo?
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No A/T is no 3B, 3A is fine and it's still easier than flying the classic but less rewarding.
But, it appears that oceanic airspace may not be allowed due to entry requirements of 1 FMC. (Please provide a link to show this). Would it make sense to consider a re-route further north onto a Russian Route in order to continue and perhaps refuel in Sapporo?
Per our FCOM, an FMC is required for CPDLC/ADS-C operations and/or for entry into Class II Navigation airspace.
How long does it take to get overflight approval and an entry window for a Russian route?
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For Airbus pilots
Dual FMGS failure need not be all of this. FMGS has two parts the FM part and the FG part. Try to engage the Auto pilot and ATHR if the FG is still available it will engage. If both have failed then try manual reset, if it doesn't work then if equipped with BACK UP NAV select that you have flight plan and some limited functions.
Dual FMGS failure need not be all of this. FMGS has two parts the FM part and the FG part. Try to engage the Auto pilot and ATHR if the FG is still available it will engage. If both have failed then try manual reset, if it doesn't work then if equipped with BACK UP NAV select that you have flight plan and some limited functions.