Four whites on PAPI: Go around?
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From: ...
And what if the papi's are at 2.5 degrees? For instance LIBR rwy 31. Normal approach path is 3 degrees, so if you follow that normal path the PAPI will indicate high.
Last edited by 737Jock; 27th March 2013 at 11:06.
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From: England
I did once, as per SOP. Got a call from the FSO the next day wondering why we went around as he couldn't see anything wrong!
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From: Tring, UK
What height AAL is the visual reference acquired?
What is the groundspeed?
What kind of aircraft?
If you're high enough, an increase in RoD to capture the appropriate profile might be possible, followed by a reduction rather than keeping it the same all the way to the ground.
If the GS is 120kts, at 1,000fpm you're not far off a 5deg GS - not what most would call stable, unless it's an approach into LCY. At 160kts, it's just over 3.5degs, on the edge of one red three whites territory.
A turboprop with rapid response to power demands and plenty of drag when the power is taken off is very different to a slippery jet with high-bypass engines. Also, the potential is there for a) a heavy landing, due to the high RoD and low power/lack of response or b) landing deep due overcompensating and flaring too high.
Either way, you're adding risk at a critical stage of flight. As a 'heavy' driver, if I had already passed the point at which stable approached criteria were assessed and maintained, in IMC, then became visual with four whites, I would go-around.
What is the groundspeed?
What kind of aircraft?
If you're high enough, an increase in RoD to capture the appropriate profile might be possible, followed by a reduction rather than keeping it the same all the way to the ground.
If the GS is 120kts, at 1,000fpm you're not far off a 5deg GS - not what most would call stable, unless it's an approach into LCY. At 160kts, it's just over 3.5degs, on the edge of one red three whites territory.
A turboprop with rapid response to power demands and plenty of drag when the power is taken off is very different to a slippery jet with high-bypass engines. Also, the potential is there for a) a heavy landing, due to the high RoD and low power/lack of response or b) landing deep due overcompensating and flaring too high.
Either way, you're adding risk at a critical stage of flight. As a 'heavy' driver, if I had already passed the point at which stable approached criteria were assessed and maintained, in IMC, then became visual with four whites, I would go-around.
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From: last time I looked I was still here.
How much fuel you got? In these days of minimum fuel departure, arriving with RESV +100 is not uncommon. Long RWY, Mk.1 eyeball and ROD<1000fpm, safer to land than join the queue and start screaming "fuel!"
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From: Birmingha,
Surely one of two things has happened here. 1 - you never got the aircraft established on the published vertical profile, in which case it the approach has not gone to plan and I would be very much go around minded. 2 - assuming PAPIs and instrument profile are the same angle then it sounds like a QNH blunder error. In this case go around check the QNH and start again.
In both cases if the cloud break is early enough then maybe it could be rescued but the aim must surely be to stabilise on the correct profile and not fly 4 whites all the way down. I don't see how anyone could consider that a stabilised approach.
In both cases if the cloud break is early enough then maybe it could be rescued but the aim must surely be to stabilise on the correct profile and not fly 4 whites all the way down. I don't see how anyone could consider that a stabilised approach.
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From: Seattle
I disagree with the assertions of a non-stabilized approach. Once more, we do not have enough information to make that judgement.
For example, on a visual approach at a steady 1000 fpm descent, this could be a perfectly "stable" and acceptable approach. If the runway is long enough, a safe landing could be made. Even if on an ILS, if the "4 white" PAPI equated to less than a half-dot deviation above the G/S, the approach could be considered stable, and a safe landing could be made after continuing at the 1000 fpm descent rate. As noted by a few above, there are airports where a 1000 fpm descent on short final is routine.
Still, I would not question anyone if he decided to go around in the situation. As for Lord Spandex Masher's FSO, he needs a different job if he is questioning a pilot's decision to go around ANY time!
For example, on a visual approach at a steady 1000 fpm descent, this could be a perfectly "stable" and acceptable approach. If the runway is long enough, a safe landing could be made. Even if on an ILS, if the "4 white" PAPI equated to less than a half-dot deviation above the G/S, the approach could be considered stable, and a safe landing could be made after continuing at the 1000 fpm descent rate. As noted by a few above, there are airports where a 1000 fpm descent on short final is routine.
Still, I would not question anyone if he decided to go around in the situation. As for Lord Spandex Masher's FSO, he needs a different job if he is questioning a pilot's decision to go around ANY time!
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From: South, near the end of the world.
According to my previous company SOP, as long as a touch down can be assure in the touch down zone the approach and landing can be continued.
And also depends in what altitude you are talking about.
According to Airbus FCOM 3. Procedures a 1 DOT deviation at 50 ft AGL is equivalent to 7 ft path deviation...
And also depends in what altitude you are talking about.
According to Airbus FCOM 3. Procedures a 1 DOT deviation at 50 ft AGL is equivalent to 7 ft path deviation...
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From: UK
Unfortunately this is where we are now - no experience and therefore the need for our cadet pilots to have a totally black and white SOP in order to function - a complete, all encompassing, concrete SOP ...... that takes into consideration the 4+ million variations to the scenario.
If this continues the SOP book is going to get pretty thick.
If this continues the SOP book is going to get pretty thick.
Last edited by Good Business Sense; 27th March 2013 at 21:12.
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From: England
Just goes to show what you can get away with as far as FDM goes
Originally Posted by ast83
1 - you never got the aircraft established on the published vertical profile, in which case it the approach has not gone to plan and I would be very much go around minded.
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From: Birmingha,
Yes I accept that from a legal point of view, calling visual is a way out of that situation. However, think of any subsequent inquiry, should this approach not end well. You would be accused tunnel vision or push on itis. With or without SOPs we have to draw somewhere. I believe it prudent to draw that line well within the limitations of what I, or the aircraft can do. On occasion you may find it neccessary to operate to those limit, and possibly through no fault of your own (eg on board emergency).
To be fair, everyone is posting based on their own interpretation of just how out of shape this approach is. There is plenty of information left to the imagination here. But if 1000' fpm will just maintain 4 whites all the way down, then touchdown is at best going to be at the far end of the touchdown zone. Sounds ugly to me.
A colleague of mine told me his previous company was once very proud of the low number of go arounds they had. Once they implemented OFDM and saw why that was they weren't quite so proud.
To be fair, everyone is posting based on their own interpretation of just how out of shape this approach is. There is plenty of information left to the imagination here. But if 1000' fpm will just maintain 4 whites all the way down, then touchdown is at best going to be at the far end of the touchdown zone. Sounds ugly to me.
A colleague of mine told me his previous company was once very proud of the low number of go arounds they had. Once they implemented OFDM and saw why that was they weren't quite so proud.
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From: The Wood
1. The PAPI angle may be different to the approach angle I.e. 3.5 degree approach with 3 degree PAPI. Once you've gone around for one of these on an NPA with cloud close to minimums it hits home.
2. Your ops manual should stipulate stability criteria. On the A320 in easy we are considered unstable below 500 if VS is greater than 1000 FPM on a 3 degree +/- 150 FPM per half degree change in glide path. So if on a 3 degree you need more than 1000 FPM below 500 for anything other than transient stability then you need to go around.
3. The PAPI is calibrated for different aircraft - An A320 being Cat C. In NCE on runway 04L the PAPI are calibrated for CAT D aircraft. The amount of times I see my colleague religiously stick to 2 reds 2 whites when it isn't necessarily appropriate I've lost count on.
4. Below 200' the only thing that matters is the aim point. Completely ignore the glide slope and the PAPI. In my opinion your colleague calling 'glideslope' or '3/4 whites' inside the last 200' will be why there inexperienced colleague does a hard landing.
2. Your ops manual should stipulate stability criteria. On the A320 in easy we are considered unstable below 500 if VS is greater than 1000 FPM on a 3 degree +/- 150 FPM per half degree change in glide path. So if on a 3 degree you need more than 1000 FPM below 500 for anything other than transient stability then you need to go around.
3. The PAPI is calibrated for different aircraft - An A320 being Cat C. In NCE on runway 04L the PAPI are calibrated for CAT D aircraft. The amount of times I see my colleague religiously stick to 2 reds 2 whites when it isn't necessarily appropriate I've lost count on.
4. Below 200' the only thing that matters is the aim point. Completely ignore the glide slope and the PAPI. In my opinion your colleague calling 'glideslope' or '3/4 whites' inside the last 200' will be why there inexperienced colleague does a hard landing.
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From: last time I looked I was still here.
One of the biggest problems I see here is current CRM training and F/O's (PM) 'advocating their position'. So here you are <500', stable with <1000fpm and going to impact within an acceptable area of the rwy, considering its length, winds, BA etc. However, you have a shiny newbie as PM: they're screaming their heads off to "Go Around" because they see 4W. They've been trained, even brain washed, into forcing the issue. You've come off an NPA, you are at reserve fuel, there's nothing unsafe about continuing using your years of experience ands sound judgement: it's a bit late in the day to be having a discussion about it, but it could end up nasty, especially if the PM decides to tell tales even if the OFDM doesn't. Is this really increasing safety? It is sad that the few hot heads in LHS have caused the many to be tarred with the same brush.
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From: fl
R5, I agree. The airlines have simplified things so anybody can do SOPs without screwing up. I left right before this happened but 10 years ago we knew what was safe and what wasn't. Now if you violate SOP's you get busted so decide if you want to go around and land min fuel or get busted doing what we did for decades. My retirement flight they wouldn't clear me for the approach because they were saturated so I did the illegal high dive to intercept the glide slope that can't be done now. If I had gone around as required now I would have conflicted with departing aircraft on a runway 90 degrees to us but would have had no choice.
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From: England
Wow, what was your FO doing?
You say you did an illegal high dive (what are they then Tom Daley?) on an approach that you weren't cleared for in, obviously, busy airspace because ATC was saturated and you were the most important and you think that's good?
By the way, as you appear to be out of date, you do not get "busted" for violating SOPs.
You say you did an illegal high dive (what are they then Tom Daley?) on an approach that you weren't cleared for in, obviously, busy airspace because ATC was saturated and you were the most important and you think that's good?
By the way, as you appear to be out of date, you do not get "busted" for violating SOPs.
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From: Between a rock and a hard place
You say you did an illegal high dive (what are they then Tom Daley?) on an approach that you weren't cleared for in, obviously, busy airspace because ATC was saturated and you were the most important and you think that's good?
How about: late approach clearance, now above G/S, having to do a little "dirty" dive to save the approach. Still well within common sense.
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From: England
How about -
Sounds to me like he wasn't cleared for an approach so just did it anyway, illegally.
That I can live with but is it illegal? No, didn't think so.
Of course, I wouldn't have to try and interpret things if people were clear what they meant in the first place.
they wouldn't clear me for the approach because they were saturated so I did the illegal high dive
late approach clearance, now above G/S, having to do a little "dirty" dive to save the approach. Still well within common sense.
Of course, I wouldn't have to try and interpret things if people were clear what they meant in the first place.
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From: Queensland
Depends on the aircraft type. I have seen a caribou on a 10 degree final to opposite end threshhold with a landing roll within those threshold markings.
With a swept wing jet airliner, with all other safety boxes ticked, I would consider continuing if stabilised aproach with target still within the touchdown zone, provided ROD not excessive.
PAPI is not God and I have seen military airfield PAPI installed for earlier touchdown zone. In my airliner, this PAPI target was all white.
I believe that fog can cause all white lights at lower angles. Greater caution might be needed during these conditions where PAPI might otherwise be considered useful.
A simple question but such a variety of responses.
With a swept wing jet airliner, with all other safety boxes ticked, I would consider continuing if stabilised aproach with target still within the touchdown zone, provided ROD not excessive.
PAPI is not God and I have seen military airfield PAPI installed for earlier touchdown zone. In my airliner, this PAPI target was all white.
I believe that fog can cause all white lights at lower angles. Greater caution might be needed during these conditions where PAPI might otherwise be considered useful.
A simple question but such a variety of responses.