LIDO cat3 minima
Thread Starter
Joined: Nov 2007
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From: malta
LIDO cat3 minima
Soon I will be flying on an aircraft which has cat3 capabilities, fail operational. As this company is using lido manuals/charts I am "pre studying", but don't have the possibility yet to ask questions. And the lido legend isn't the most readable thing I've ever seen... If the aircraft is fully functional, we are trained appropriately, not additions to minima, etc, what would be the cat3 minima for this approach? 
My thoughts are either, even though we can do a no DH - 75m approach, according the lido legends, the mentioned 50-200r are the lowest minima for this approach, so my minima too. Or are these the minima we must observe if, for some reason (tech?), we can't do a DH<50ft-75r (fail operational) approach? So if fail operational we can do no DH-75, otherwise 50-200. But what's the "company" line? According lido, company regs and minima must be observed. Are they only valid when those are somehow higher than the (in this case) 50-200r?
My thoughts are either, even though we can do a no DH - 75m approach, according the lido legends, the mentioned 50-200r are the lowest minima for this approach, so my minima too. Or are these the minima we must observe if, for some reason (tech?), we can't do a DH<50ft-75r (fail operational) approach? So if fail operational we can do no DH-75, otherwise 50-200. But what's the "company" line? According lido, company regs and minima must be observed. Are they only valid when those are somehow higher than the (in this case) 50-200r?
Joined: Aug 2009
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From: GPS L INVALID
The point is that when it comes to LVO its all about what your company has been approved for, you won't find the values written in the LIDO Legend, but instead in your company documentation (and the certificates by the relevant aviation authority).
Joined: Feb 2001
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From: The Winchester
the_stranger
Agree with previous:
The cat3 minima will be whatever the company has decided, and will be on the “company” page for that approach.
Problem you have with your pre-studying is it sounds as if you don’t yet have access to that bit of the documentation, it should all become a bit more clear when you do.
The cat3 minima will be whatever the company has decided, and will be on the “company” page for that approach.
Problem you have with your pre-studying is it sounds as if you don’t yet have access to that bit of the documentation, it should all become a bit more clear when you do.
Joined: Mar 2012
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From: Having a margarita on the beach
Soon I will be flying on an aircraft which has cat3 capabilities, fail operational. As this company is using lido manuals/charts I am "pre studying", but don't have the possibility yet to ask questions. And the lido legend isn't the most readable thing I've ever seen... If the aircraft is fully functional, we are trained appropriately, not additions to minima, etc, what would be the cat3 minima for this approach?
My thoughts are either, even though we can do a no DH - 75m approach, according the lido legends, the mentioned 50-200r are the lowest minima for this approach, so my minima too. Or are these the minima we must observe if, for some reason (tech?), we can't do a DH<50ft-75r (fail operational) approach? So if fail operational we can do no DH-75, otherwise 50-200. But what's the "company" line? According lido, company regs and minima must be observed. Are they only valid when those are somehow higher than the (in this case) 50-200r?
My thoughts are either, even though we can do a no DH - 75m approach, according the lido legends, the mentioned 50-200r are the lowest minima for this approach, so my minima too. Or are these the minima we must observe if, for some reason (tech?), we can't do a DH<50ft-75r (fail operational) approach? So if fail operational we can do no DH-75, otherwise 50-200. But what's the "company" line? According lido, company regs and minima must be observed. Are they only valid when those are somehow higher than the (in this case) 50-200r?
Joined: Aug 2007
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From: uk
What does your CCI 01 page say for the runway as that is your absolute minima for that particular runway.
Thread Starter
Joined: Nov 2007
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From: malta
Apparently, the MDH isn't valid, as we can we do a no DH approach. So why is it mentioned?
Is it when I am downgraded to fail.passive and have to increase my DH to 50, than the mentioned value (50-200r) becomes valid?
Joined: May 2001
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From: London,England
Apparently, the MDH isn't valid, as we can we do a no DH approach. So why is it mentioned?
Company specific authorisation is required from the state authority governing the airport to fly a CAT3 approach and those approved figures will be published on the CCI page which is company specific.
They may be higher than the minima on the top line of box but they won't, or shouldn't be, lower.
For instance the LIDO chart for Warsaw 33 shows 0-175R in the minima box so in theory the airport will allow a NO DH approach at not less that 175m but our company CCI page shows 200m and 50ft (CAT3A) so that is what we are authorised to fly and we can't go lower than that. T
The figures may have come from the authority or perhaps the company have decided that they don't want operate lower at that airport but whatever the reason those figures are the minimum you can operate to.
Last edited by Max Angle; 8th February 2025 at 12:29.
Thread Starter
Joined: Nov 2007
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From: malta
You can't do a NO DH approach, the figures on the top line are the lowest state or system installation minima.
Company specific authorisation is required from the state authority governing the airport to fly a CAT3 approach and those approved figures will be published on the CCI page which is company specific.
They may be higher than the minima on the top line of box but they won't, or shouldn't be, lower.
For instance the LIDO chart for Warsaw 33 shows 0-175R in the minima box so in theory the airport will allow a NO DH approach at not less that 175m but our company CCI page shows 200m and 50ft (CAT3A) so that is what we are authorised to fly and we can't go lower than that. T
The figures may have come from the authority or perhaps the company have decided that they don't want operate lower at that airport but whatever the reason those figures are the minimum you can operate to.
Company specific authorisation is required from the state authority governing the airport to fly a CAT3 approach and those approved figures will be published on the CCI page which is company specific.
They may be higher than the minima on the top line of box but they won't, or shouldn't be, lower.
For instance the LIDO chart for Warsaw 33 shows 0-175R in the minima box so in theory the airport will allow a NO DH approach at not less that 175m but our company CCI page shows 200m and 50ft (CAT3A) so that is what we are authorised to fly and we can't go lower than that. T
The figures may have come from the authority or perhaps the company have decided that they don't want operate lower at that airport but whatever the reason those figures are the minimum you can operate to.
And if we become fail.passive (in that case, we normally have minima of 50-175), we still have the same minima (50-200r) at this specific approach?
Joined: May 2001
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From: London,England
It really isn't that hard, you are over thinking it, forget the minima page on the plate, for CAT3 operations you fly to whatever your company specific CCI page says.
Fail operational (CAT3 DUAL in Airbus speak) and fail passive (CAT3 SINGLE or CAT2) aren't associated with any specific minima, they are the operational landing capability based on the technical state of the aircraft.
If you have CAT3 DUAL on the FMA you can operate down to whatever CAT3B minima are included on the CCI page, if you have CAT3 SINGLE you can only go down to CAT3A minima and if CAT2 down to the CAT2 minima on the approach plate.
BUT be aware that some failures that downgrade landing capability are not sensed by the aircraft (Windshield heat, standby horizon etc.) so with a failure you must check the required equipment table to check you still have the required landing capability.
Fail operational (CAT3 DUAL in Airbus speak) and fail passive (CAT3 SINGLE or CAT2) aren't associated with any specific minima, they are the operational landing capability based on the technical state of the aircraft.
If you have CAT3 DUAL on the FMA you can operate down to whatever CAT3B minima are included on the CCI page, if you have CAT3 SINGLE you can only go down to CAT3A minima and if CAT2 down to the CAT2 minima on the approach plate.
BUT be aware that some failures that downgrade landing capability are not sensed by the aircraft (Windshield heat, standby horizon etc.) so with a failure you must check the required equipment table to check you still have the required landing capability.
Only half a speed-brake
Joined: Apr 2003
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From: Commuting not home
You may not need a company page at all. Our case was easy: We operated C3-operational under EASA to the NoDH-75 standard.
So we asked LIDO to print the minima boxes in all our manuals to EASA specs, which we had in our OM-A, and that was it. (you can even ask Jeppesen to do this for you; it is so pricey nobody does). The AOM where lower, applicable for our 737-4/500 and A321 for France were kept in OM-B / Type Operating Limitations - near where the demonstrated cross-wind was converted to company hard limits.
I understand why some airlines or NAAs might want to have those in OM-C but let's not confuse the OP by saying that as a given.
Only half a speed-brake
Joined: Apr 2003
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From: Commuting not home
To OP: what you are seeing is MOST LIKELY just LIDO showing you the lowest minima authorized for the approach (is that Belgium?). If your company minima is less, you need to observe the more conservative value you already suggested.
If it is still a thing, be careful for France, where NoDH-75 was not authorized thus 0-75 was printed meaning "must have a DH". For our 321 the AFM would require C3-OP + DH to be around 21'.
If it is still a thing, be careful for France, where NoDH-75 was not authorized thus 0-75 was printed meaning "must have a DH". For our 321 the AFM would require C3-OP + DH to be around 21'.
Thread Starter
Joined: Nov 2007
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From: malta
I'm still utterly confused.
I asked and this company does not know CCI pages. It does have company minima, which states, fail operational you can do from NO DH tot 99 feet, with a minimum rvr of 75 (dh<50) and 175 (50<dh<99).
This particular approach is the 08r at LROP and the only thing I want to know, if I do fly there with my shiny Airbus, what minima do I put in the box?
And what visibility do I need to continue the approach/use for planning?
I'm both reading our company limits (So no DH and 75m as well as the mentioned limits 50-200.)
I asked and this company does not know CCI pages. It does have company minima, which states, fail operational you can do from NO DH tot 99 feet, with a minimum rvr of 75 (dh<50) and 175 (50<dh<99).
This particular approach is the 08r at LROP and the only thing I want to know, if I do fly there with my shiny Airbus, what minima do I put in the box?
And what visibility do I need to continue the approach/use for planning?
I'm both reading our company limits (So no DH and 75m as well as the mentioned limits 50-200.)
Joined: May 2001
Posts: 1,424
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From: London,England
if I do fly there with my shiny Airbus, what minima do I put in the box?
Perhaps it would be more useful to ask your employer, they must an approval so the figures will be somewhere.
Who is the operator? If the figures aren't available for a particular runway they may not have approval to operate CAT3 on to it so I would be cautious.
Thread Starter
Joined: Nov 2007
Posts: 225
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From: malta
Whatever the company tells you to, you won't get it from LIDO unless the company has used the CCI page (Company and Crew Information) or had them printed on the main plate which it seems they haven't.
Perhaps it would be more useful to ask your employer, they must an approval so the figures will be somewhere.
Who is the operator? If the figures aren't available for a particular runway they may not have approval to operate CAT3 on to it so I would be cautious.
Perhaps it would be more useful to ask your employer, they must an approval so the figures will be somewhere.
Who is the operator? If the figures aren't available for a particular runway they may not have approval to operate CAT3 on to it so I would be cautious.
Of course I will ask later, but really would like to get to grips with it, if possible.
So assuming there indeed are CCI pages, can they show values below what is mentioned on the minima box. So below 50-200r in this case?
If not, question answered I guess. I use the ones in the CCI.
If they can show lower values and I if do use those lower values, what does the minima box tell me then? Assume the CCI shows 20-75r, what do I do with the mentioned 75-200r?
Reading the lido legends, it seems to come down to this part:
Which seems to suggest that for this specific LROP approach, there is no cat 3-75R published, there is only a cat 3-175r available, which is also slightly raised to 200r.
So even in my fail-operational Airbus I still need to use at least the minima (50-200r) shown in the box as there is no "better" (cat3-75r), unless the company limits (either in CCI or else) are even higher.
(I'm not naming the airline yet, as I'm slightly paranoid about giving too much personal info away, but it's a western Europe legacy.)
Joined: Mar 2012
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From: Having a margarita on the beach
Thanks all for trying to explain it, it might help me get closer to understanding.
Of course I will ask later, but really would like to get to grips with it, if possible.
So assuming there indeed are CCI pages, can they show values below what is mentioned on the minima box. So below 50-200r in this case?
If not, question answered I guess. I use the ones in the CCI.
If they can show lower values and I if do use those lower values, what does the minima box tell me then? Assume the CCI shows 20-75r, what do I do with the mentioned 75-200r?
Reading the lido legends, it seems to come down to this part:
Which seems to suggest that for this specific LROP approach, there is no cat 3-75R published, there is only a cat 3-175r available, which is also slightly raised to 200r.
So even in my fail-operational Airbus I still need to use at least the minima (50-200r) shown in the box as there is no "better" (cat3-75r), unless the company limits (either in CCI or else) are even higher.
(I'm not naming the airline yet, as I'm slightly paranoid about giving too much personal info away, but it's a western Europe legacy.)
Of course I will ask later, but really would like to get to grips with it, if possible.
So assuming there indeed are CCI pages, can they show values below what is mentioned on the minima box. So below 50-200r in this case?
If not, question answered I guess. I use the ones in the CCI.
If they can show lower values and I if do use those lower values, what does the minima box tell me then? Assume the CCI shows 20-75r, what do I do with the mentioned 75-200r?
Reading the lido legends, it seems to come down to this part:
Which seems to suggest that for this specific LROP approach, there is no cat 3-75R published, there is only a cat 3-175r available, which is also slightly raised to 200r.
So even in my fail-operational Airbus I still need to use at least the minima (50-200r) shown in the box as there is no "better" (cat3-75r), unless the company limits (either in CCI or else) are even higher.
(I'm not naming the airline yet, as I'm slightly paranoid about giving too much personal info away, but it's a western Europe legacy.)
OM-A 8.4
OM-C Airfield briefings or other LVO related chapters
LVO Manual (if it’s a legacy there will be something like this)
Eidolon
Joined: May 2001
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From: Some hole
My thoughts are either, even though we can do a no DH - 75m approach, according the lido legends, the mentioned 50-200r are the lowest minima for this approach, so my minima too. Or are these the minima we must observe if, for some reason (tech?), we can't do a DH<50ft-75r (fail operational) approach? So if fail operational we can do no DH-75, otherwise 50-200. But what's the "company" line? According lido, company regs and minima must be observed. Are they only valid when those are somehow higher than the (in this case) 50-200r?
Just because the aircraft is NO DH capable still need
- Airport qualified
- Airline approval
- Crew qualified
Thread Starter
Joined: Nov 2007
Posts: 225
Likes: 15
From: malta
But apart from that, it still doesn't answer the question. What does the weather line(lido term, in this case 50-200r) tell me, what do i use it for and what is the link with the second line (company)?
If I am fully trained for no DH approaches and the aircraft is fail-oper., the one thing left is the airport. Does the 50-200r tell me that runway is designed as such that the lowest minima for that runway/approach is 50-200r? And therefore also my minima (assuming there is no airline higher limit)?
If not, what does it tell me?
(The company has no CCI pages, only company minima which go as low as no-dh/75m).
