Airbus: Flying an ILS not in the database
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john_smith
I have already answered how to fly airbus like an archaic aircraft. The questions asked do not give the impression that the pilot has gone through type rating because he would go through FCOM first before taking advice from the public.
I have already answered how to fly airbus like an archaic aircraft. The questions asked do not give the impression that the pilot has gone through type rating because he would go through FCOM first before taking advice from the public.
You never stop learning with the airbus.
The Fcom also states-
This pushbutton arms, disarms, engages, or disengages the approach modes:
LOC and G/S modes, if an ILS approach is selected in the active F-PLN.
APP NAV-FINAL modes, if a non precision approach is selected in the active F-PLN.
Dsc22_10-20-40
As to ground speed mini the fcom states
TWR HEADWIND COMPONENT
The TWR HEADWIND COMPONENT is the component of the MAG WIND projected on the runway axis (landing runway entered in the flight plan). It is used to compute VAPP and GS mini.
How does it compute it correctly if there is no runway in the F-PLN? I was taught that this is why we activate the secondary when circling.
The Fcom also states-
This pushbutton arms, disarms, engages, or disengages the approach modes:
LOC and G/S modes, if an ILS approach is selected in the active F-PLN.
APP NAV-FINAL modes, if a non precision approach is selected in the active F-PLN.
Dsc22_10-20-40
As to ground speed mini the fcom states
TWR HEADWIND COMPONENT
The TWR HEADWIND COMPONENT is the component of the MAG WIND projected on the runway axis (landing runway entered in the flight plan). It is used to compute VAPP and GS mini.
How does it compute it correctly if there is no runway in the F-PLN? I was taught that this is why we activate the secondary when circling.
Last edited by tubby linton; 18th Apr 2015 at 13:50.
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Agreed GS mini can be active anywhere provided there is RW in MCDU. About approach is selected means even if ILS frequency and course is tuned is considered selected.
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Hi Armann
I guess thread is again veering off from its path. I will simply try to answer your questions,
1 There is no FAC in A 330, but there is FE as part of FMGEC, which is akin to functions to FAC.
2. To understand what the LAND is, you should know how the airplane makes AUTOLAND in X wind up to its limit 20Kts.
Answer: Same as I do: "De-crab Technique, if you dare to make Automatic Landing in real x wind around 20K or in SIM, you will see that. Around flare height AP aligns the airplane crab heading with runway direction. You can easily see this through windshield and fell rudder pedal movement (feed back) under your foot. This is called "ALIGN" mode (check DSC). This is an AP mode but is transparent to pilot. What I mean, it engages like other FMA modes but does not display on FMA. To be able to that, AP needs to know runway direction, this is the runway direction in MCDU which is selected for landing. Theoretically this is the same with ILS front course in RAD NAV. Practically, what I had tried in SIM, MCDU runway direction vs. RAD NAV front course may be 2 or 3 degree different to get the LAND mode on FMA. Beyond that angular difference, LAND mode does not engage (see PRO_NOR_SRP), eventually A/P disengages. That is fail passive.
3. Regardless which mode you were before (I mean even you do not Activate App or do not sequence FPLN properly etc), as long as you extend flap out of zero, with TOGA selection , GA mode will engage. GA TRK and pitch up will engage. Obviously there will not be any NAV mode to engage (in the sample you give). If you above the PERF page THR RED ACC/ ACC altitude THR LVR CLB will flash immediately and OPN CLB will engage anyway (provided FCU altitude above airplane altitude)
Not: You may be aware, ILS course concept is completely different than VOR bearing concept. What I mean, if you are flying full raw data, setting correct course to anywhere for any type of airplane has no function other than situational awareness of pilot while he is trying to center the deviation bar. For example if front course of ILS is 360 but 345 is set on MCDU (or somewhere else on other type airplane), as long as airplane is on LOC line through approach, deviation bar still indicates centered. Again I remind this is correct only for raw data flight. However, If any Autoflight mode is engaged ( FD and/or AP) then this course may be important for computer internal calculations like intercepting angle, correction factor etc.
I guess thread is again veering off from its path. I will simply try to answer your questions,
1 There is no FAC in A 330, but there is FE as part of FMGEC, which is akin to functions to FAC.
2. To understand what the LAND is, you should know how the airplane makes AUTOLAND in X wind up to its limit 20Kts.
Answer: Same as I do: "De-crab Technique, if you dare to make Automatic Landing in real x wind around 20K or in SIM, you will see that. Around flare height AP aligns the airplane crab heading with runway direction. You can easily see this through windshield and fell rudder pedal movement (feed back) under your foot. This is called "ALIGN" mode (check DSC). This is an AP mode but is transparent to pilot. What I mean, it engages like other FMA modes but does not display on FMA. To be able to that, AP needs to know runway direction, this is the runway direction in MCDU which is selected for landing. Theoretically this is the same with ILS front course in RAD NAV. Practically, what I had tried in SIM, MCDU runway direction vs. RAD NAV front course may be 2 or 3 degree different to get the LAND mode on FMA. Beyond that angular difference, LAND mode does not engage (see PRO_NOR_SRP), eventually A/P disengages. That is fail passive.
3. Regardless which mode you were before (I mean even you do not Activate App or do not sequence FPLN properly etc), as long as you extend flap out of zero, with TOGA selection , GA mode will engage. GA TRK and pitch up will engage. Obviously there will not be any NAV mode to engage (in the sample you give). If you above the PERF page THR RED ACC/ ACC altitude THR LVR CLB will flash immediately and OPN CLB will engage anyway (provided FCU altitude above airplane altitude)
Not: You may be aware, ILS course concept is completely different than VOR bearing concept. What I mean, if you are flying full raw data, setting correct course to anywhere for any type of airplane has no function other than situational awareness of pilot while he is trying to center the deviation bar. For example if front course of ILS is 360 but 345 is set on MCDU (or somewhere else on other type airplane), as long as airplane is on LOC line through approach, deviation bar still indicates centered. Again I remind this is correct only for raw data flight. However, If any Autoflight mode is engaged ( FD and/or AP) then this course may be important for computer internal calculations like intercepting angle, correction factor etc.
Last edited by JABBARA; 18th Apr 2015 at 18:20. Reason: Editorial
No Fly Zone; I'm sorry, but yours was such a 
post, why are you so scared of Airbus?
Do you manually change gears in your car with a clutch and stick shift, or do you trust an auto gearbox to do all that and get it right for you 99% of the time?
Also in your car; Do you have a manual choke or do you trust this function to an engine management system? Do you ever use cruise control? Parking sensors?
At home; do you manually tune in your TV to the channel you want each time, and adjust the hue control, or does the computer in your TV do that for you?
etc....
post, why are you so scared of Airbus?Do you manually change gears in your car with a clutch and stick shift, or do you trust an auto gearbox to do all that and get it right for you 99% of the time?
Also in your car; Do you have a manual choke or do you trust this function to an engine management system? Do you ever use cruise control? Parking sensors?
At home; do you manually tune in your TV to the channel you want each time, and adjust the hue control, or does the computer in your TV do that for you?
etc....
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Pro-nor-srp-01-70 p 8/26 fcom ← b → 18 mar 15
APPROACH MODE ACTIVATION (LOC-G/S)
When cleared by ATC and when appropriate:
DEPRESS the APPR pushbutton to arm the APPR mode for the approach entered in the flight plan.
Note: If a NON PRECISION approach is selected in the active flight plan and if the flight crew manually tunes an ILS on the RAD NAV page, the MCDU and the PFD display "CHECK APPR SELECTION". This message is a reminder to the flight crew that, although an ILS is tuned on RAD NAV page, the available approach guidance modes are APP NAV-FINAL when the APPR pushbutton is pressed in on the FCU.
The FCU APPR pushbutton arms or engages LOC and G/S modes, if:
‐ An ILS approach is entered in the flight plan, or
‐ No approach, or only a runway, is entered in the flight plan, and an ILS is manually-tuned on the RAD NAV page, or
‐ Both RMPs are set to NAV, and an ILS is selected
CAUTION
If the pilot decides to fly the ILS approach without revising the arrival of the primary flight plan (a non ILS approach is in the F-PLN), LOC and G/S modes will not be available when he presses the APPR pushbutton. Consequently, he should:
• Manually TUNE in the ILS on the RAD NAV page: CHECK that the "CHECK APPR SELECTION" message comes up.
• Press the ILS pushbutton and select ROSE ILS on the EIS CONTROL panel.
• Use HDG, V/S or TRK, FPA modes to fly the ILS.
When cleared by ATC and when appropriate:
DEPRESS the APPR pushbutton to arm the APPR mode for the approach entered in the flight plan.
Note: If a NON PRECISION approach is selected in the active flight plan and if the flight crew manually tunes an ILS on the RAD NAV page, the MCDU and the PFD display "CHECK APPR SELECTION". This message is a reminder to the flight crew that, although an ILS is tuned on RAD NAV page, the available approach guidance modes are APP NAV-FINAL when the APPR pushbutton is pressed in on the FCU.
The FCU APPR pushbutton arms or engages LOC and G/S modes, if:
‐ An ILS approach is entered in the flight plan, or
‐ No approach, or only a runway, is entered in the flight plan, and an ILS is manually-tuned on the RAD NAV page, or
‐ Both RMPs are set to NAV, and an ILS is selected
CAUTION
If the pilot decides to fly the ILS approach without revising the arrival of the primary flight plan (a non ILS approach is in the F-PLN), LOC and G/S modes will not be available when he presses the APPR pushbutton. Consequently, he should:
• Manually TUNE in the ILS on the RAD NAV page: CHECK that the "CHECK APPR SELECTION" message comes up.
• Press the ILS pushbutton and select ROSE ILS on the EIS CONTROL panel.
• Use HDG, V/S or TRK, FPA modes to fly the ILS.
That is an interesting point Gryphon.if you fly a non precision approach and then divert to an ILS equipped airport that is not in the database the guidance will not work. I suppose you could just enter no approach or a runway to get it to work but what modes does it revert to below 400ft ra?
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Hi tubby linton,
We did this in the sim the other day.
With nothing in the flight plan and selected the ILS frequency & Course in the Rad Nav - all the normal modes were displayed (LAND, FLARE etc)
what modes does it revert to below 400ft ra?
With nothing in the flight plan and selected the ILS frequency & Course in the Rad Nav - all the normal modes were displayed (LAND, FLARE etc)
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I said so too. Not difficult to understand. MCDU plays no part in an ILS approach which is done by capturing LOC and GS. But if you select a NPA in MCDU then the system is programmed for it and ignores ILS tuning.
Last edited by vilas; 22nd Apr 2015 at 03:20.
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Golden Rivett;
At your trial, was the AP engaged?
When I tried in SIM, an ILS & RWY selected on MCDU, only I overwrite the front course around 5 degree different than original. Then the LAND mode did not display and A/P disconnected. I consider it consists with the image below except here it advises to disengage A/P , but when I tried, it automatically disengaged.
At your trial, was the AP engaged?
When I tried in SIM, an ILS & RWY selected on MCDU, only I overwrite the front course around 5 degree different than original. Then the LAND mode did not display and A/P disconnected. I consider it consists with the image below except here it advises to disengage A/P , but when I tried, it automatically disengaged.
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It says clearly in the diagram that if the selected course is wrong then LAND mode will not be displayed. So the FMS must be crosschecking pilot entered runway to compare front course inserted in RAD NAV. That's why in JABARRAs case the AP disconnected. Goldenrivett said he had NOTHING at all in the flight plan, that may be the difference, no runway to cross check for the FMS so it continued?
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Hi Airman,
The diagram posted in #31 suggests you fly a GA if there is no LAND mode displayed by 350 ft. If the ILS course is incorrect then you have to revert CAT II minimums and perform a manual Landing.
Airbus FCOM has the least amount of information of any aircraft I've flown.
The data is locked (ILS Frequency & QDM) at 700 Radio, so why wait until 350 ft to check it?
On a previous AC type which was approved for NO DH & 75m, the ILS Course was changed by rotating the Omni Bearing Selector (OBS). It was possible to change it accidentally (HDG knob near by), so the very last chance we had to ensure it was set correctly was by 350 ft - else we reverted CAT II minimums for Manual Landing. 350 ft was chosen because that's when the "Align" software calculated the heading change for the AutoLand touch down.
In post #29, we re-positioned the sim from the ground somewhere to finals ILS somewhere else. No Flight Plan, Tuned ILS Frequency & QDM on Rad Nav page, Armed the Approach and flew the ILS manually for a Crosswind Landing. All the normal Auto Land modes appeared. I'll try with the AP in next time - and I'm confident it will remain engaged and Auto Land.
if the selected course is wrong then LAND mode will not be displayed
Airbus FCOM has the least amount of information of any aircraft I've flown.
The data is locked (ILS Frequency & QDM) at 700 Radio, so why wait until 350 ft to check it?
On a previous AC type which was approved for NO DH & 75m, the ILS Course was changed by rotating the Omni Bearing Selector (OBS). It was possible to change it accidentally (HDG knob near by), so the very last chance we had to ensure it was set correctly was by 350 ft - else we reverted CAT II minimums for Manual Landing. 350 ft was chosen because that's when the "Align" software calculated the heading change for the AutoLand touch down.
In post #29, we re-positioned the sim from the ground somewhere to finals ILS somewhere else. No Flight Plan, Tuned ILS Frequency & QDM on Rad Nav page, Armed the Approach and flew the ILS manually for a Crosswind Landing. All the normal Auto Land modes appeared. I'll try with the AP in next time - and I'm confident it will remain engaged and Auto Land.
Last edited by Goldenrivett; 22nd Apr 2015 at 17:14. Reason: typos
Yep, that would be interesting, and would be the same I suppose, if you emergency tuned the ILS and course on the RCP?
Did you get ground speed mini - presumably not if you input no data?
Did you get ground speed mini - presumably not if you input no data?
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Hi Uplinker,
Not so much as you would notice. (as Nancy Sinatra sang)
I think GS mini needs to know the Runway QDM from the Flight Plan data.
See FCTM explanation.
"GROUND SPEED MINI FUNCTION PRINCIPLE
.... Wind is a key factor in the "ground speed mini function".
TWR WIND
It is the MAG WIND entered in the PERF APPR page. It is the average wind as provided by the ATIS or the tower. Gusts must not be inserted, they are included in the ground speed mini computation.
TWR HEADWIND COMPONENT
The TWR HEADWIND COMPONENT is the component of the MAG WIND projected on the runway axis (landing runway entered in the flight plan). It is used to compute VAPP and GSmini.
CURRENT HEADWIND COMPONENT
The actual wind measured by ADIRS is projected on the aircraft axis to define the CURRENT HEADWIND COMPONENT (instantaneous headwind).
The CURRENT HEADWIND COMPONENT is used to compute the variable speed target during final (IAS target)."
Did you get ground speed mini
I think GS mini needs to know the Runway QDM from the Flight Plan data.
See FCTM explanation.
"GROUND SPEED MINI FUNCTION PRINCIPLE
.... Wind is a key factor in the "ground speed mini function".
TWR WIND
It is the MAG WIND entered in the PERF APPR page. It is the average wind as provided by the ATIS or the tower. Gusts must not be inserted, they are included in the ground speed mini computation.
TWR HEADWIND COMPONENT
The TWR HEADWIND COMPONENT is the component of the MAG WIND projected on the runway axis (landing runway entered in the flight plan). It is used to compute VAPP and GSmini.
CURRENT HEADWIND COMPONENT
The actual wind measured by ADIRS is projected on the aircraft axis to define the CURRENT HEADWIND COMPONENT (instantaneous headwind).
The CURRENT HEADWIND COMPONENT is used to compute the variable speed target during final (IAS target)."
Well, the very last line that you quoted there, suggests that you would get GS mini, although it is calling it 'variable speed target'
Just something to bear in mind if I ever need to do this
Just something to bear in mind if I ever need to do this
I cannot see the need to fly GS mini if it is not being computed correctly. A selected speed with a wind correction would work equally as well and is used by thousands of Boeings every day.
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GS mini is a function of FMGS so it will need RW to calculate. If PERF page doesn't show RW and wind it will not work. Ground speed mini is a concept to keep constant energy and directional inertia. Airbus does it automatically but since we are discussing flying without any input in MCDU it should be understood that just like everything else it can be used purely manually. Use manual thrust and vary the airspeed target to keep constant ground speed threshold. That's what ATHR does.
Last edited by vilas; 26th Apr 2015 at 12:32.
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Hello all,
I´ve read most of the posts on this thread.
They are all technically correct.
It is an interesting question for a well argumented technical discussion.
The way I see it is that many are relying too much on automation and forget that automation is there to help you reduce your workload. And most of the time it works perfectly as long as you feed it with the correct information.
Don´t forget that the flight laws are the same for every aircraft regardless of its level of automation.
A/P basic modes are HDG/ALT. Those work well, are readily available and override whatever information you put in the box.
Remember revert to your basic fliying skills. If they are well cemented you should have no problem getting rid if automation and fly a modern jetliner like any other general aviation aircraft.
I´ve read most of the posts on this thread.
They are all technically correct.
It is an interesting question for a well argumented technical discussion.
The way I see it is that many are relying too much on automation and forget that automation is there to help you reduce your workload. And most of the time it works perfectly as long as you feed it with the correct information.
Don´t forget that the flight laws are the same for every aircraft regardless of its level of automation.
A/P basic modes are HDG/ALT. Those work well, are readily available and override whatever information you put in the box.
Remember revert to your basic fliying skills. If they are well cemented you should have no problem getting rid if automation and fly a modern jetliner like any other general aviation aircraft.
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Relevant extracts from FCOM
The FCU APPR pushbutton arms or engages LOC and G/S modes, if:
‐ An ILS approach is entered in the flight plan, or
‐ No approach, or only a runway, is entered in the flight plan, and an ILS is manually-tuned on the RAD NAV page, or
‐ Both RMPs are set to NAV, and an ILS is selected.
PRO- NOR - SRP - 01- 70 P5/12
CAUTION
If the pilot decides to fly the ILS approach without revising the arrival of the primary flight plan (a non ILS approach is in the F-PLN), LOC and G/S modes will not be available when he presses the APPR pushbutton.
Consequently, he should:
• Manually TUNE in the ILS on the RAD NAV page: CHECK that the "CHECK APPR SELECTION" message comes up.
• Press the ILS pushbutton and select ROSE ILS on the EIS CONTROL panel.
• Use HDG, V/S or TRK, FPA modes to fly the ILS
P 10/12 same section
So, when only runway and no approach is selected. Then manually tune ils, course, arm approach and go.
But if another approach is already in, then will have to fly hdg, vs/trk fpa.
This explains.
‐ An ILS approach is entered in the flight plan, or
‐ No approach, or only a runway, is entered in the flight plan, and an ILS is manually-tuned on the RAD NAV page, or
‐ Both RMPs are set to NAV, and an ILS is selected.
PRO- NOR - SRP - 01- 70 P5/12
CAUTION
If the pilot decides to fly the ILS approach without revising the arrival of the primary flight plan (a non ILS approach is in the F-PLN), LOC and G/S modes will not be available when he presses the APPR pushbutton.
Consequently, he should:
• Manually TUNE in the ILS on the RAD NAV page: CHECK that the "CHECK APPR SELECTION" message comes up.
• Press the ILS pushbutton and select ROSE ILS on the EIS CONTROL panel.
• Use HDG, V/S or TRK, FPA modes to fly the ILS
P 10/12 same section
So, when only runway and no approach is selected. Then manually tune ils, course, arm approach and go.
But if another approach is already in, then will have to fly hdg, vs/trk fpa.
This explains.
