A320 Status page Appr spd
Thread Starter
Joined: Jul 2009
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From: London
A320 Status page Appr spd
Heya guys,
Just wondering if someone could confirm with a reference whether the status page on the A320 is dynamic.
When is says Appr spd: VREF +25
Is this dependant on current aircraft config. With some failures (flaps + slats locked) as you configure this speed shown may change depending on the current config?
Just wondering if someone could confirm with a reference whether the status page on the A320 is dynamic.
When is says Appr spd: VREF +25
Is this dependant on current aircraft config. With some failures (flaps + slats locked) as you configure this speed shown may change depending on the current config?
Only half a speed-brake
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From: Commuting not home
The speeds on FMGS are static. The computer will pull Vls for CF Full or 3 dependant on pilot selection from a table of weights, and apply wind corrections as per algorithm. The machine does not know the status of the aircraft. The procedure for calculating Vapp for failure cases is purely manual based on QRH tables.
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From: CASEY STATION
VREF + 25 is independent of actual configuration anyway. VREF is relating to full only. The + 25 ( in this example ) is to make a speed allowance for configuration ( when different to full ) and/or to improve handling quality.
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From: Wanderlust
The machine does not know the status of the aircraft. The procedure for calculating Vapp for failure cases is purely manual based on QRH tables.
Only half a speed-brake
Joined: Apr 2003
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From: Commuting not home
By "the machine" in the part vilas quoted I ment FMS. Trying too hard to avoid the word "box" that I loathe. 
Sorry for any confusion caused.
Lantrin: No, it is not always correct. And the wording is slightly misleading too. But nitpicking aside, yes it may and should be used. (for single type failures when FWC correctly and in full reports what's gone wrong. Assuming one does not forget to properly work out a/thr and ice accretion additives)
Sorry for any confusion caused. Lantrin: No, it is not always correct. And the wording is slightly misleading too. But nitpicking aside, yes it may and should be used. (for single type failures when FWC correctly and in full reports what's gone wrong. Assuming one does not forget to properly work out a/thr and ice accretion additives)
Only half a speed-brake
Joined: Apr 2003
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From: Commuting not home
Eh, no, but not my point.
1) the STS shows delta V(failure). To calculate Vapp you need to take into account A/THR additive, wind correction and ice accretion. So into the QRH anyhow.
2) Real problems sometimes come in pairs, i.e. you dispatch with 1 pair of spoilers locked closed per MEL and then something ...
3) It is actually fine, but only if the malfunction plays by the rules.
It was more of a general comment aimed at the word ALWAYS. I remeber OEB for dual bleed fault and dispatching with 1 side inop - and the paper procedure was clearly not designed for such configuration. So, whenever the clever systems come to show me something, I always approach with caution and proceed further only once having verified the problem (for which a solution is being presented) is the exact one I actually have. As a computer kid, I refuse to take them at face value.
One of my early SIM instructors used to say: "the travesty normally begins as people correctly execute a wrong NNC". That was 737 with a printed set in QRH, but FWC does not shield us completely from the very same trap.
1) the STS shows delta V(failure). To calculate Vapp you need to take into account A/THR additive, wind correction and ice accretion. So into the QRH anyhow.
2) Real problems sometimes come in pairs, i.e. you dispatch with 1 pair of spoilers locked closed per MEL and then something ...
3) It is actually fine, but only if the malfunction plays by the rules.
It was more of a general comment aimed at the word ALWAYS. I remeber OEB for dual bleed fault and dispatching with 1 side inop - and the paper procedure was clearly not designed for such configuration. So, whenever the clever systems come to show me something, I always approach with caution and proceed further only once having verified the problem (for which a solution is being presented) is the exact one I actually have. As a computer kid, I refuse to take them at face value.
One of my early SIM instructors used to say: "the travesty normally begins as people correctly execute a wrong NNC". That was 737 with a printed set in QRH, but FWC does not shield us completely from the very same trap.
Thread Starter
Joined: Jul 2009
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From: London
Just to clarify, as I can see my question is a tad vague.
I have an Airbus PDP (Procedure data package which is an Airbus produced document) and it says for a slats fault or flaps locked (essentially where flaps or slats are locked in an unusual config for landing) then on he staus page it has an approach speed correction. I used +25 as an arbitrary figure.
It says the approach speed correction on the status page is dependent on current flap and slat position and is updated for landing?
I can't find that anywhere in the FCOM.
Cheers for the answers so far guys.
I have an Airbus PDP (Procedure data package which is an Airbus produced document) and it says for a slats fault or flaps locked (essentially where flaps or slats are locked in an unusual config for landing) then on he staus page it has an approach speed correction. I used +25 as an arbitrary figure.
It says the approach speed correction on the status page is dependent on current flap and slat position and is updated for landing?
I can't find that anywhere in the FCOM.
Cheers for the answers so far guys.
Joined: Jun 2007
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From: Wanderlust
PilotJames
True. The slat/flap can jam in different combinations and the STS page gives you the appropriate Vref addition to allow you to calculate Vapp. It is not the STS page but the VLS that you see is gets updated as you configure. As I wrote before VLS is real time speed. Its displayed value is always correct whether in normal or abnormal situation with one surface jammed.
It says the approach speed correction on the status page is dependent on current flap and slat position and is updated for landing?
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From: London
In the sim I had a g hyd loss + y overheat. It came up with vref + 25. (Which is worst case for slats only) As it was a stopping problem we agreed to turn on the y pump on base, and hopefully keep the pump for the brakes.
So we configured on downwind and got slats only as expected. (Flap 3)
We then turned on the y elec pump for the app. It worked for about a minute before it overheated again. In that time the flaps ran out.
On reviewing the status page the delta vref was now+ 10,(as we now had slats & flaps)
So if I understand your question yes the delta vref does update on the status page as things change, but no I can't give you a reference.
So we configured on downwind and got slats only as expected. (Flap 3)
We then turned on the y elec pump for the app. It worked for about a minute before it overheated again. In that time the flaps ran out.
On reviewing the status page the delta vref was now+ 10,(as we now had slats & flaps)
So if I understand your question yes the delta vref does update on the status page as things change, but no I can't give you a reference.
Joined: Jun 2007
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From: Wanderlust
PilotJames
STS page is part of ECAM so it is always dynamic with failures. Let's say you have slats jam the STS page gives you Vref+25. This is a speed additive to Vref to know Vapp. When you start configuring by taking flap it will still show Vref+25 but while selecting flaps if you get a flaps jam the STS page will take a note of it and give you different additive may be Vref+60 or alternately if you recover some slat as Pony stated it will may give you Vref+10.
It means dependant on current flap/slat jam position not on configuration. It will only change if the jammed slat/flap position changes.
STS page is part of ECAM so it is always dynamic with failures. Let's say you have slats jam the STS page gives you Vref+25. This is a speed additive to Vref to know Vapp. When you start configuring by taking flap it will still show Vref+25 but while selecting flaps if you get a flaps jam the STS page will take a note of it and give you different additive may be Vref+60 or alternately if you recover some slat as Pony stated it will may give you Vref+10.
It says the approach speed correction on the status page is dependent on current flap and slat position and is updated for landing?
Last edited by vilas; 6th November 2016 at 02:33.
