Why FOQA catchs this?
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Why FOQA catchs this?
Hi gentlemans:
My company's FOQA has a detection item which is if you are at an altitude between 1000 feet and 100 feet during final approach with a pich angle >7 degrees ,Then is will be limit 1 detection ,if >9 it will be limit 2 detection.Since our pitch angle on a ILS is already 5 degrees(ERJ190).I really don"t know Why FOQA catchs this?
My company's FOQA has a detection item which is if you are at an altitude between 1000 feet and 100 feet during final approach with a pich angle >7 degrees ,Then is will be limit 1 detection ,if >9 it will be limit 2 detection.Since our pitch angle on a ILS is already 5 degrees(ERJ190).I really don"t know Why FOQA catchs this?
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+5 pitch attitude on final??? Any other 190 pilots confirm that?
Curious because I've typically seen 2.5-3 degrees nose up on various jets and the E190 doesn't appear to have TWICE the nose up attitude of other a/c on approach.
And a 2 degree increase in nose up attitude from normal is a significant change.
Curious because I've typically seen 2.5-3 degrees nose up on various jets and the E190 doesn't appear to have TWICE the nose up attitude of other a/c on approach.
And a 2 degree increase in nose up attitude from normal is a significant change.
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kuobin,
As FOQA becomes more widespread, naturally more pilots will be interested in the details. And I do not wish to diminish your commendable curiousity for anything technical in aviation.
However, the best way for a line pilot to approach FOQA is to simply know that it is there, and avoid making any decisions or developing any techniques based on your knowledge of FOQA events and alert thresholds.
To do so would be the equivalent of assessing your car driving skills by looking only in your rear vision mirror and examining where you have been, and noting the location and severity of dents when you park.
Far better to relate any FOQA event and threshold to FCOM recommended Procedures and Techniques for your type.
And ensure that your pilot representative body has adequate arrangements covering the use and confidentiality of QAR data.
Having said that, I should descend from my pulpit!
Remember that Power + Attitude = Performance.
In the range of 1000' to 100' on final approach, you should be stabilised in the approach configuration. You are not yet in the landing flare.
You say your type has a typical pitch attitude of 5 deg ANU (aircraft nose up) in landing config when on glideslope.
I am guessing that your Vapp is in the vicinity of 120kt-140kt. Giving a target descent rate of 600-700fpm to maintain a 3 degree path to the touchdown point.
At 120KIAS a pitch attitude change of 1 degree roughly equates to a 200'/min change in RoD or RoC.
Therefore a 2 degree ANU change would reduce your rate of descent by approximately 400fpm and a 4 degree ANU change would reduce your rate of descent by approximately 800fpm.
Assuming that 120KIAS is maintained by you or your autothrottles.
Therefore FOQA wants to know why you have selected a pitch attitude that would normally result in only a 200-300fpm descent (level 1) or level flight to +200fpm climb when the target is a 600-700fpm rate of descent.
The attitude is not one that would normally provide a stabilised approach.
Does that assist?
As FOQA becomes more widespread, naturally more pilots will be interested in the details. And I do not wish to diminish your commendable curiousity for anything technical in aviation.
However, the best way for a line pilot to approach FOQA is to simply know that it is there, and avoid making any decisions or developing any techniques based on your knowledge of FOQA events and alert thresholds.
To do so would be the equivalent of assessing your car driving skills by looking only in your rear vision mirror and examining where you have been, and noting the location and severity of dents when you park.
Far better to relate any FOQA event and threshold to FCOM recommended Procedures and Techniques for your type.
And ensure that your pilot representative body has adequate arrangements covering the use and confidentiality of QAR data.
Having said that, I should descend from my pulpit!
Remember that Power + Attitude = Performance.
In the range of 1000' to 100' on final approach, you should be stabilised in the approach configuration. You are not yet in the landing flare.
You say your type has a typical pitch attitude of 5 deg ANU (aircraft nose up) in landing config when on glideslope.
I am guessing that your Vapp is in the vicinity of 120kt-140kt. Giving a target descent rate of 600-700fpm to maintain a 3 degree path to the touchdown point.
At 120KIAS a pitch attitude change of 1 degree roughly equates to a 200'/min change in RoD or RoC.
Therefore a 2 degree ANU change would reduce your rate of descent by approximately 400fpm and a 4 degree ANU change would reduce your rate of descent by approximately 800fpm.
Assuming that 120KIAS is maintained by you or your autothrottles.
Therefore FOQA wants to know why you have selected a pitch attitude that would normally result in only a 200-300fpm descent (level 1) or level flight to +200fpm climb when the target is a 600-700fpm rate of descent.
The attitude is not one that would normally provide a stabilised approach.
Does that assist?
Last edited by ITCZ; 26th Nov 2008 at 08:27.
I must admit I was surprised at the deck angle on touchdown of the E190. Pretty high!
If the nose is already at 5° on final, only another 2° for a FOQA soft alert seems way too harsh to me. The nose could quite happily waffle +/- 3°-4° without causing any significant change to the flight path (and hence Rate of Descent) but in this case would cause the FOQA to go berserk.
ITCZ,
You may not advocate looking in the rearvision mirror, but the fact of the matter is the FOQA reports/trigger points have a direct effect on how crews fly the aeroplane. Why would one not try to avoid a FOQA event, knowing that it will be registered (albeit [perhaps] not attributed to me)? It is not natural to do something that you know is going to be registered.
These situations are helpful because they put pressure on the boffins who set the FOQA parameters to adjust them, like Pitch Attitude High on Rotation!
If the nose is already at 5° on final, only another 2° for a FOQA soft alert seems way too harsh to me. The nose could quite happily waffle +/- 3°-4° without causing any significant change to the flight path (and hence Rate of Descent) but in this case would cause the FOQA to go berserk.
ITCZ,
You may not advocate looking in the rearvision mirror, but the fact of the matter is the FOQA reports/trigger points have a direct effect on how crews fly the aeroplane. Why would one not try to avoid a FOQA event, knowing that it will be registered (albeit [perhaps] not attributed to me)? It is not natural to do something that you know is going to be registered.
These situations are helpful because they put pressure on the boffins who set the FOQA parameters to adjust them, like Pitch Attitude High on Rotation!
Moderator
but the fact of the matter is the FOQA reports/trigger points have a direct effect on how crews fly the aeroplane
(a) although an expected human trait, it is an indictment of the operator's approach to the subject ?
(b) in the same vein as flying a check flight like one flies the line, and vice versa, some of the FOQA value is lost if it ceases to be a transparent looksee facility
(c) much depends on mutual trust between operator and crew. Surely the principal aim is to effect incremental improvements in SOP ?
(d) procedural handling of cowboy pilot actions detected by FOQA needs to be done in a manner which doesn't destroy the underlying relationship between the operator and the more disciplined crews who represent the very great majority.
(a) although an expected human trait, it is an indictment of the operator's approach to the subject ?
(b) in the same vein as flying a check flight like one flies the line, and vice versa, some of the FOQA value is lost if it ceases to be a transparent looksee facility
(c) much depends on mutual trust between operator and crew. Surely the principal aim is to effect incremental improvements in SOP ?
(d) procedural handling of cowboy pilot actions detected by FOQA needs to be done in a manner which doesn't destroy the underlying relationship between the operator and the more disciplined crews who represent the very great majority.
