A 320 - automatic rollout function after autoland
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A 320 - automatic rollout function after autoland
Hello all
Kindly help me with this
Where is it mentioned in A320 FCOM or SOP that:
CAT 3 SINGLE (fail passive) automatic landings are landings without automatic roll out function
and
CAT 3 DUAL automatic landings are with automatic rollout function
If no such mention is given in FCOM or other documents then how do I determine my crosswind limitation for automatic landing since they are different for automatic landing with automatic rollout and without automatic roll out
How do i know if I will have automatic rollout or no automatic roll out , since I need to determine my crosswind limitation
Thank you for your help in advance
Regards
Kindly help me with this
Where is it mentioned in A320 FCOM or SOP that:
CAT 3 SINGLE (fail passive) automatic landings are landings without automatic roll out function
and
CAT 3 DUAL automatic landings are with automatic rollout function
If no such mention is given in FCOM or other documents then how do I determine my crosswind limitation for automatic landing since they are different for automatic landing with automatic rollout and without automatic roll out
How do i know if I will have automatic rollout or no automatic roll out , since I need to determine my crosswind limitation
Thank you for your help in advance
Regards
Joined: Mar 2023
Posts: 25
Likes: 8
From: Madrid
Hello all
Kindly help me with this
Where is it mentioned in A320 FCOM or SOP that:
CAT 3 SINGLE (fail passive) automatic landings are landings without automatic roll out function
and
CAT 3 DUAL automatic landings are with automatic rollout function
If no such mention is given in FCOM or other documents then how do I determine my crosswind limitation for automatic landing since they are different for automatic landing with automatic rollout and without automatic roll out
How do i know if I will have automatic rollout or no automatic roll out , since I need to determine my crosswind limitation
Thank you for your help in advance
Regards
Kindly help me with this
Where is it mentioned in A320 FCOM or SOP that:
CAT 3 SINGLE (fail passive) automatic landings are landings without automatic roll out function
and
CAT 3 DUAL automatic landings are with automatic rollout function
If no such mention is given in FCOM or other documents then how do I determine my crosswind limitation for automatic landing since they are different for automatic landing with automatic rollout and without automatic roll out
How do i know if I will have automatic rollout or no automatic roll out , since I need to determine my crosswind limitation
Thank you for your help in advance
Regards
From a legal perspective, if you need to have Automatic Rollout to have certain minima (75m vs 175m or No DH vs 50RA) then the system capability displayed when you arm approach is CAT3DUAL(and of course taking those non monitored systems into acount), and the crosswind needs to be within the 15kts limit. What happens when you have CAT3DUAL displayed but crosswind is 16-20kts? Then you would have to apply the minima applicable to an Automatic Landing without Automatic Rollout, which will probably be higher, and disconnect the autopilot once you’ve touched down(I cannot be certain about it as my operator has a 15kt crosswind limit for manual rollout so I haven’t been explained how to get advantage of those extra 5kts of crosswind, but there are AC where the limitation for automatic rollout is more than 15kts and this logic is applied on the inverse, so it makes sense).
From the autopilot capabilities point of view, let’s say you only have one AP operative and thus are limited to CAT3Single. If the crosswind is 15kts or bellow, there will be no damage to keep the AP on after landing, it will not disconnect on its own and should be able to handle it happily. But, once again, if the crosswind is above the 15kt threshold, the AP is certified capable of decrabing the AC but not of keeping it on the runway, and you should take over once you’re on the ground. Same logic applies to CAT2 system capability, the AP should handle happily a 15kt crosswind on rollout, but not a 20kt one.
Thread Starter
Joined: Mar 2018
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I would separate two aspects, the legal and the Autopilot’s certified capabilities. For this I am assuming the runway is clear and with a CAT III installation.
From a legal perspective, if you need to have Automatic Rollout to have certain minima (75m vs 175m or No DH vs 50RA) then the system capability displayed when you arm approach is CAT3DUAL(and of course taking those non monitored systems into acount), and the crosswind needs to be within the 15kts limit. What happens when you have CAT3DUAL displayed but crosswind is 16-20kts? Then you would have to apply the minima applicable to an Automatic Landing without Automatic Rollout, which will probably be higher, and disconnect the autopilot once you’ve touched down(I cannot be certain about it as my operator has a 15kt crosswind limit for manual rollout so I haven’t been explained how to get advantage of those extra 5kts of crosswind, but there are AC where the limitation for automatic rollout is more than 15kts and this logic is applied on the inverse, so it makes sense).
From the autopilot capabilities point of view, let’s say you only have one AP operative and thus are limited to CAT3Single. If the crosswind is 15kts or bellow, there will be no damage to keep the AP on after landing, it will not disconnect on its own and should be able to handle it happily. But, once again, if the crosswind is above the 15kt threshold, the AP is certified capable of decrabing the AC but not of keeping it on the runway, and you should take over once you’re on the ground. Same logic applies to CAT2 system capability, the AP should handle happily a 15kt crosswind on rollout, but not a 20kt one.
From a legal perspective, if you need to have Automatic Rollout to have certain minima (75m vs 175m or No DH vs 50RA) then the system capability displayed when you arm approach is CAT3DUAL(and of course taking those non monitored systems into acount), and the crosswind needs to be within the 15kts limit. What happens when you have CAT3DUAL displayed but crosswind is 16-20kts? Then you would have to apply the minima applicable to an Automatic Landing without Automatic Rollout, which will probably be higher, and disconnect the autopilot once you’ve touched down(I cannot be certain about it as my operator has a 15kt crosswind limit for manual rollout so I haven’t been explained how to get advantage of those extra 5kts of crosswind, but there are AC where the limitation for automatic rollout is more than 15kts and this logic is applied on the inverse, so it makes sense).
From the autopilot capabilities point of view, let’s say you only have one AP operative and thus are limited to CAT3Single. If the crosswind is 15kts or bellow, there will be no damage to keep the AP on after landing, it will not disconnect on its own and should be able to handle it happily. But, once again, if the crosswind is above the 15kt threshold, the AP is certified capable of decrabing the AC but not of keeping it on the runway, and you should take over once you’re on the ground. Same logic applies to CAT2 system capability, the AP should handle happily a 15kt crosswind on rollout, but not a 20kt one.
Thank you for your reply
I wanted to know where in FCOM is it given that CAT 3 single is without rollout and CAT 3 DUAL is with roll out
Joined: Mar 2023
Posts: 25
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From: Madrid
It is not given anywhere I think, because the automatic rollout is available in CAT2, CAT3SINGLE and CAT3DUAL unless there is some other failure. It used to be the case in our OM-A that for automatic rollout we used to require a CAT III fail operational status, and that is why I got confused, but it is no longer there. So the answer to which minima apply to you will depend on your operator, not on anything written on the FCOM.
Thread Starter
Joined: Mar 2018
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It is not given anywhere I think, because the automatic rollout is available in CAT2, CAT3SINGLE and CAT3DUAL unless there is some other failure. It used to be the case in our OM-A that for automatic rollout we used to require a CAT III fail operational status, and that is why I got confused, but it is no longer there. So the answer to which minima apply to you will depend on your operator, not on anything written on the FCOM.
Thank you for your reply once again
I understand from what you are saying that CAT 3 dual and CAT 3 single and CAT 2 is capable of doing automatic rollout , and I take crosswind limitations for AUTOLAND with rollout function
But my question is how do I know of a failure which affects my rollout capability , How do I know there is a failure which makes my autoland "WITHOUT ROLLOUT"
As far as a I know status page does not mention such a downgrade such as "NO ROLLOUT"
How will I know a failure affects my rollout to SO THAT I use crosswind limitation for AUTOLAND WITHOUT ROLL OUT
Thank you for taking time to respond , appreciate your help
Joined: Aug 2023
Posts: 70
Likes: 27
From: London
Check your QRH, under required equipment for CAT2/3.
There is a note near the bottom regarding automatic rollout where 1 of all of the following is required for automatic rollout: BSCU channel, anti-skid, and NWS. Without any one of them autoroll out is not available/to be used, but you can still do CAT 3 single and CAT 2, however your vis minima changes slightly; specifically CAT 3 single your midpoint minimum visibility changes from 75m to 125m.
It is worth noting that the maximum crosswind component with auto rollout is based around using maximum thrust reverse on the most adverse engine during an engine failure scenario. The aircraft in reality is likely very capable during normal low visibility ops able to handle substantially more than the maximum crosswind limitation with auto rollout; therefore it could be argued that it may be pragmatic and reduces workload to keep auto rollout engaged above the maximum wind limitation and monitor it, and then takeover as required. Check FCOM LIM-AFS Automatic Landing for a note that essentially infers this… “provided the wind does not exceed the maximum wind conditions for automatic rollout”.
There is a note near the bottom regarding automatic rollout where 1 of all of the following is required for automatic rollout: BSCU channel, anti-skid, and NWS. Without any one of them autoroll out is not available/to be used, but you can still do CAT 3 single and CAT 2, however your vis minima changes slightly; specifically CAT 3 single your midpoint minimum visibility changes from 75m to 125m.
It is worth noting that the maximum crosswind component with auto rollout is based around using maximum thrust reverse on the most adverse engine during an engine failure scenario. The aircraft in reality is likely very capable during normal low visibility ops able to handle substantially more than the maximum crosswind limitation with auto rollout; therefore it could be argued that it may be pragmatic and reduces workload to keep auto rollout engaged above the maximum wind limitation and monitor it, and then takeover as required. Check FCOM LIM-AFS Automatic Landing for a note that essentially infers this… “provided the wind does not exceed the maximum wind conditions for automatic rollout”.
