AIRBUS Dual RA fault & Flight control laws
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You have to make your decision before you start your approach. You are not allowed to start a Cat II or III without RAs. Some airlines provide you with complete lists of things you need for approach. RAs are two of them.
Dani
Dani
Ut Sementem Feeceris
From FCTM:
At take-off, normal law becomes active when the MLG is no longer
compressed and pitch attitude becomes greater than 8°
On approach, flare law becomes active when the L/G is selected down and
provided AP is disconnected. At this point, “USE MAN PITCH TRIM” is
displayed on the PFD.
A4
At take-off, normal law becomes active when the MLG is no longer
compressed and pitch attitude becomes greater than 8°
On approach, flare law becomes active when the L/G is selected down and
provided AP is disconnected. At this point, “USE MAN PITCH TRIM” is
displayed on the PFD.
A4
Beau_Peep
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On A320.....
upon L/G selection during app, Directl law activates and at this point the ECAM (STS) will ask for flaps 3 & spd & ldg dist increment....
After takeoff with RA 1+2 fault, Direct law is active until L/G is selected up.
If I remember correctly, A330/A340 behave the same way..
upon L/G selection during app, Directl law activates and at this point the ECAM (STS) will ask for flaps 3 & spd & ldg dist increment....
After takeoff with RA 1+2 fault, Direct law is active until L/G is selected up.
If I remember correctly, A330/A340 behave the same way..
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May be only the EGPWS alerting system is inoperative
Only half a speed-brake
Whether inside the A320 the GPWS and EGPWS are in fact two separate systems, or - as the acronym would suggest - the enhanced functions are built atop the core GPWS is not known. There are no technical reasons why RA failure should affect EGPWS. I am not saying they don't on the aeroplane, that's down to internal logic.
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Hello guys!
At the moment, I am in my type rating program on A320. That is why, i want to ask about DUAL RA FAILURE (RA 1+2 FAULT).
The question is, should I fly as the same LOC G/S out, using FPA ? (on the final stage)
At the moment, I am in my type rating program on A320. That is why, i want to ask about DUAL RA FAILURE (RA 1+2 FAULT).
The question is, should I fly as the same LOC G/S out, using FPA ? (on the final stage)
Only half a speed-brake
Yes, LOC+FPA. The A/P should not be left engaged too long (it is written), however. Then FD=off.
Good luck with your training, enjoy the aeroplane!
Good luck with your training, enjoy the aeroplane!
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A330 and 320 differ in redundancies. As someone said A330 is not a big A320. In A320 Approach mode cannot be armed as it requires inputs from RA. An easier way to fly ILS is treat initially as an NPA. With AP on and TRK/FPA, arm LOC. After LOC capture configure to Flap 2. Then put the gear down AP off, FDs off, set RW track and then on fly raw data ILS.
I have often wondered how the Flight Guidance would perform for an Rnav approach with a double RA failure. I know that it is not good with an ILS as it uses the RA to tune the sensitivity of the LOC as you get closer to the ground, but I wonder if the same logic is used for an RNAV (GPS)?
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I have often wondered how the Flight Guidance would perform for an Rnav approach with a double RA failure. I know that it is not good with an ILS as it uses the RA to tune the sensitivity of the LOC as you get closer to the ground, but I wonder if the same logic is used for an RNAV (GPS)?
Only half a speed-brake
Would there even be a need for any such logic? The LOC is getting more narrow closer to the runway (and ground), hence the FD-AP (do not remember which one) gains need to be adjusted to avoid over-controlling. I think this may not apply to the internal guidance at all.
Two more thoughts:
while the sequence described by vilas is perfectly fine, I reckon the type rating course will demonstrate LOC+FPA for this excercise.
Secondly, is there an agreement on how close is too close, so that the AP needs to come off? I always guessed 1500 ft-ish.
Two more thoughts:
while the sequence described by vilas is perfectly fine, I reckon the type rating course will demonstrate LOC+FPA for this excercise.
Secondly, is there an agreement on how close is too close, so that the AP needs to come off? I always guessed 1500 ft-ish.
Last edited by FlightDetent; 15th Feb 2019 at 12:29.
Thinking about it you would need to have a flight director to fly an rnav-gps as there is no raw data.I would still be interested to see how the guidance reacts with a double RA failure.
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Interestingly, some of our airplanes require F3 for landing in this case. For others, landing config isn't specified. Does anyone have any reason why this is so?
Last edited by Check Airman; 15th Feb 2019 at 00:17.
Only half a speed-brake
Wow, I always thought DCT law was F3 by design requirement. And dual RA is that due to no flare mode, A330/340 included. Slap me if I deserve it, could it be a typo in the manuals?
With regards to F3 then gear-down: I remeber that as well in the past. Later, with a wider undestanding on what were the appropriate instructing philosophies, the company mantra changed - no tricks outside the book were recommended, only smart application of it. Hence for dual RA, unlike in G+Y HYD where the summary advises the swap, standard sequence would be used. But we would deccelerate to F speed before dropping the wheels, goal achieved. Vapp(f3) to F speed difference is insignificant.
With regards to F3 then gear-down: I remeber that as well in the past. Later, with a wider undestanding on what were the appropriate instructing philosophies, the company mantra changed - no tricks outside the book were recommended, only smart application of it. Hence for dual RA, unlike in G+Y HYD where the summary advises the swap, standard sequence would be used. But we would deccelerate to F speed before dropping the wheels, goal achieved. Vapp(f3) to F speed difference is insignificant.
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The A320 has been landing CONF 3 in direct law for the past 31 years, not sure this is different today, unless the latest MSNs have a new F/CTL software. I have always highly discouraged configuring to CONF 3 then L/G DOWN in a DUAL RA, as the EMER CANC for a legitimate non spurious warning is against the Airbus philosophy.
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I have always highly discouraged configuring to CONF 3 then L/G DOWN in a DUAL RA,
There is a perfectly serviceable trim wheel available - which for some reason Airbus pilots are reluctant to use.
Boeing pilots must be laughing their sox off.
Only half a speed-brake
sweet memories of Toulouse. "Merci(*), what on Earth stops you from landing gear up after cancelling it?!"Further study of the FCOM ABN L/G for that warning shows there's logic specifically designed to ensure with DUAL RA the bells go off with L/G UP and F3.
For landing F3: MSN 7000+ both CEO and NEO in our library have that for the landing.
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* I am sure with the first syllable "mer", the following one not too much.
Last edited by FlightDetent; 15th Feb 2019 at 15:30. Reason: grammar