Delta A330-300 Lands Short in Amsterdam
Even if runway 22 was the only designated landing runway at that time, I think ATC would likely accommodate a request for a circling to runway 24 if needed. It is not uncommon to see freight carriers using the Sierra apron and KLM Cityhopper aircraft that park on apron Alpha use that procedure.
If memory serves me well I have landed a 777 on that runway (an empty one going into maintenance). It's not a big deal. However those same vague memories also makes me believe, that the general "feeling" the runway gave many pilots was not the most relaxed one because of the lack of shoulders and the "shorter than usual" distance.
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Can I ask a "threat and error management" question
Why are heavies being obliged to use runway 22 at an airport where five longer runways are available.
Seems to be an unnecessary threat.
Would EHAM have permitted rejection of that runway.as I heard a BA 787 do at New Orleans the other day ( reject 20 in favour of 11).
Why are heavies being obliged to use runway 22 at an airport where five longer runways are available.
Seems to be an unnecessary threat.
Would EHAM have permitted rejection of that runway.as I heard a BA 787 do at New Orleans the other day ( reject 20 in favour of 11).
That gives you 4 runways to land on, 22/27/18C/18R (24,18L are not used for approach or landing, with 24 sometimes available for a break-off from 22/27)
The 18C was closed due maintenance and the 18R was deemed to have too much Xwind.
Leaves 22 and 27, but at the time, SPL had an outbound peak, requiring 2 runways to start from.
As 22 is a terrible runway to depart from (logistic wise for aircraft not based on the east part of SPL), 27 was used besides 24.
As 22 is a perfectly fine runway, there was and is no reason to change that. However, if a pilot requires the 27, ATC will give it but with (substantial) delay. The same, or worse for an eventual break-off to 24. Those "extra" landings would screw up the departure flow quite a lot.
Again, it might be the shortest runway and maybe short compared to what most are used to, but by no means a runway which is special, dangerous or to be avoided. Especially an a330, which stops on a dime, should have no more issues than a embraer or b737 (which probably requires more runway).
If this short runway is regularly used for landing I am surprised it hasn't been extended to properly accommodate wide-bodies. There is room to extend past the 04 threshold to the RET taxiway that serves 18L. They wouldn't even have to move the 04 threshold, just keep it as displaced similar to the area ahead of 18L. This would give it a similar length to 22L at JFK which has been used for decades for wide-body arrivals without incident (SAS (1984) not withstanding!)
That is why aircraft cross the threshold at 50', does not explain how they lost 100' in less than 400' (horizontally, ie 14 degree path) if they were on slope.
On a Boeing, if the autothrottle is used for the landing, there is no need for wind corrections on top of the standard 5kts (all Boeings afaik). If autothrottle is/will be switched off for landing, command speed is increased with a wind correction up to 20kts. Main wind corrections can be bled off over the runway, but gust corrections on the speed should be kept in. With the autothrottle, the system reacts aggressive if speed would drop below command speed, especially if you hit Vref, which is why the standard 5kts is sufficient.
What are the rules for the commanded speed with or without autothrust on an Airbus?
On a Boeing, if the autothrottle is used for the landing, there is no need for wind corrections on top of the standard 5kts (all Boeings afaik). If autothrottle is/will be switched off for landing, command speed is increased with a wind correction up to 20kts. Main wind corrections can be bled off over the runway, but gust corrections on the speed should be kept in. With the autothrottle, the system reacts aggressive if speed would drop below command speed, especially if you hit Vref, which is why the standard 5kts is sufficient.
On a Boeing, if the autothrottle is used for the landing, there is no need for wind corrections on top of the standard 5kts (all Boeings afaik). If autothrottle is/will be switched off for landing, command speed is increased with a wind correction up to 20kts. Main wind corrections can be bled off over the runway, but gust corrections on the speed should be kept in. With the autothrottle, the system reacts aggressive if speed would drop below command speed, especially if you hit Vref, which is why the standard 5kts is sufficient.
On top of this, G/S Minimum functions as well to provide a buffer if the instantaneous headwind component as computed by the IRs is greater than the tower provided headwind component, the aircraft will add the difference in headwind to the approach speed in anticipation of it being lost as the aircraft descends to the runway. In this case for example, with a VAPP of VREF+9, with the headwind on the ground of 28kts being expected, if at 500' there was a 38knot headwind, the "Fly Speed" would be VREF+19, if at 300' the headwind component was 33kts, the fly speed would be VREF+14, and so on, with the objective being that as the wind dies off the closer you get to the runway, the negative sheer is counteracted by the target speed reducing, and that you cross the threshold at the calculated VAPP (VREF+9 in this case).
All that being said, despite the extra margin being provided by G/S Mini and the VAPP increments in strong headwinds, I've always found the Auto-Thrust, both on the A330 and A320 to let you down at the worst possible moment. It can often get itself out of sync with the gusts and the speed and result in an automatic form of PIO with the thrust and can be quite slow to add power, even when the speed sinks down to or below the VLS (VREF).
Personally I've always found manual thrust the best option on both the A320 and A330 when landing in blustery conditions, it allows better anticipation of speed drops and gains and allows for local knowledge to be applied, as is often known about different airports, such as passing a certain hangar or passing by a certain ditch. It allows you to maintain current thrust setting in areas where you know a gain in airspeed will be short lived and soon die off (whereas auto-thrust would reduce thrust and then whack it back on as the speed bleeds off) or in the case of Schipol, manual thrust allows you to anticipate the drop in speed you often get in the last 40-80 feet as you descend below the tree line.
A320 Auto-Thrust performs reasonably well 90% of the time but the A330 auto-thrust in particular can often let you down for whatever reason, be it the larger engines and inertia, or just a different software gain/adjustment for counteracting airspeed reductions.
While I don't care to overly speculate, it would not surprise me that in the final report the use of auto-thrust, perhaps no additional increment being put on the VAPP due to concerns of the shorter than normal runway, the possibility of the aircraft getting low to begin with due to pilot mental perception of the shorter runway or just blustery conditions may all be listed as contributary factors.
Just worth mentioning as well though from experience, despite the shorter runway length, given the prevailing conditions, headwind, sea level, cool temperatures etc, even with a wet runway, Airbus landing performance figures from rough experience would still give you about a ~60% margin and I'd expect the calculated LDR would be in the region of 1,200m-1,300m, leaving a 700m-800m margin on the landing rollout on the 2,000m runway, and that being with proper technique (crossing threshold at 50', touchdown within touchdown zone etc.), so by no means overly limiting or close to the minimum 15% margin required.
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If this short runway is regularly used for landing I am surprised it hasn't been extended to properly accommodate wide-bodies. There is room to extend past the 04 threshold to the RET taxiway that serves 18L. They wouldn't even have to move the 04 threshold, just keep it as displaced similar to the area ahead of 18L. This would give it a similar length to 22L at JFK which has been used for decades for wide-body arrivals without incident (SAS (1984) not withstanding!)
Most widebodies can land with 50% of the runway remaining and for those who can't or won't, 27 is available (with delay).
22 has been used of a decade at least without any incident except this one. I know a little (with emphasis on little) challenge is scary nowadays, but every pilot worth his salary should be able to land on a runway his performance figures indicate to be adequate.
Originally Posted by Pattern is full
Add 1m to that eyepoint-tread height to account for strut extension and eagleclaw-tilted bogie position, to estimate the pilot's eyes will be 8m (26.4 ft) above the trailing main gear wheel tread.
Originally Posted by Brace Brace
I do would like to add these ideas are related to the 747 (maybe A380 as well?). Not "heavies". Even on a 777 you use same procedures as on a 737. There is no reason to go higher.
https://www.airbus.com/sites/g/files...ation-v5.0.pdf
Gives a A330-300 eye to wheel height of over 10m.
By my calculations, on that runway, with an assumed PAPI angle of 3° located at just under 287m (giving a MEHt of 49ft), the wheels will cross the fence at 12ft and touchdown, with no flare, at less than 50m in. And that is on 2W2R. That is why they install "big jet" PAPIs with a MEHt of around 65ft.
Anybody thinking a 777 is the same as a 737 is this scenario is, IMO, mistaken.
Originally Posted by EI_DVM
with proper technique (crossing threshold at 50', touchdown within touchdown zone etc.
The 330 may have great brakes; it's where the PAPI leaves you which is the problem.
By my calculations, on that runway, with an assumed PAPI angle of 3° located at just under 287m (giving a MEHt of 49ft), the wheels will cross the fence at 12ft and touchdown, with no flare, at less than 50m in. And that is on 2W2R. That is why they install "big jet" PAPIs with a MEHt of around 65ft.
Anybody thinking a 777 is the same as a 737 is this scenario is, IMO, mistaken.
Made more difficult when the PAPI "encourages" your mains to be only 12ft over the piano keys.
The 330 may have great brakes; it's where the PAPI leaves you which is the problem.
Anybody thinking a 777 is the same as a 737 is this scenario is, IMO, mistaken.
Made more difficult when the PAPI "encourages" your mains to be only 12ft over the piano keys.
The 330 may have great brakes; it's where the PAPI leaves you which is the problem.
By my calculations, on that runway, with an assumed PAPI angle of 3° located at just under 287m (giving a MEHt of 49ft), the wheels will cross the fence at 12ft and touchdown, with no flare, at less than 50m in. And that is on 2W2R. That is why they install "big jet" PAPIs with a MEHt of around 65ft.
https://eaip.lvnl.nl/2023-01-12-AIRA...dex-en-GB.html
Originally Posted by SWH
Per the AIP (EHAM AD 2.14 APPROACH AND RUNWAY LIGHTING), the MEHT for RW22 PAPI is 62ft.
It also looks like the GS ground antenna is around 255m. From those Airbus figures, that would put the GS antenna over the threshold at 44ft, wheel height around 17ft.
Looking at the 747 video, they were 4 whites at the minimum and pretty much on GS. Given the glideslope would well below the PAPI if it was at 62ft, you expect to see at least one red.
A 2-bar VASI is not to be used (because yes, with a 3° path the main gear will touchdown near the end of the runway), a 3-bar VASI gives 3.25° and this is the "long-body" configuration you keep confusing with the PAPI system. It's a VASI specification, not a PAPI.
The PAPI's are perfectly safe to be used by any 777 "2 reds, 2 whites", whatever the body length, because the touchdown point is not the same as for a glideslope. They will guide an aircraft further along down the runway. This basic parameter is the one where you guys are doing pretty hard "guesswork" it seems (correct me if I'm wrong though). That doesn't mean there are variations to account for, but that is indeed, the pilot's job. The first "P" in PAPI is precision, and it will tell you when you are too low.
Last edited by BraceBrace; 21st Jan 2023 at 08:51.
Several inter-related aspects in recent posts.
Runway length per se relates to the landing distance required, which is referenced to "15m (50 ft) above the landing surface", taken to be the nominal 'threshold'. AMC CS 25-1592
Certification accepts (appears to assume) that there will be some variation in TCH re 'use of procedures' and the nebulous 'pilots of average skill'; as indicated by the distribution of wheel touchdown positions.
PAPI is an angular guidance system indicating the required flight path angle.
An approach flown with constant 3Red or 3White will have an angular offset, but still guiding to the same position on the runaway. The TCH for approaches with one light deviation will have different TCH, but not significant wrt to the range of crossing altitudes in normal operations i.e. normal flight path variations (beware combinations of extremes - lower designed TCH, low approach + wind-shear).
An non-standard approach 3W becoming 4W, flown parallel to the approach path (pseudo long body) requires judgement of the longitudinal distance relative to PAPI as to where the change in indications occur (2W - 3W - 4W).
Without real-time computation the height displacement from the PAPI flight path is unknown - a judgement, which if excessive can result in a touchdown further down the runway, invalidating landing distance calculations (risk of overrun). A mis judged deliberate offset vs normal variability.
Increasing the distance between PAPI and the threshold (higher TCH):
If the PAPI was repositioned SW on the existing runway 22 then the TCH would be higher. This would not reduce landing distance available (same threshold); but the hazard of the lip between runway / grass still remains - possibility of wheel brake damage as discussed.
Retaining the current PAPI location but extending the runway by moving the threshold of 22 NE would again increase TCH, and ironically increase the LDA - new threshold, but again the hazard remains.
However, retaining the existing threshold and adding hardstanding to the NE should reduce the hazard - less likely to occur, compare with 27 wheel marks, but this may not reduce the perception of 'safety risk' from an early touchdown 27 vs 22 - already discussed.
Thus if 'it' can happen, 'it' will happen, and if 'it' happens on 22, then the higher safety risk from the hazard.
This is an issue for operational awareness, but not within pilots capability to reduce the risk; that's the 'hard' task for the airport - remove / reduce the hazard.
Bloggs #50
swh, thanks for the info; don't forget that with the correct TCH eye ht for the flt deck, the wheels are behind and lower, and lower still when they cross the threshold.
BraceBrace " The PAPI's are perfectly safe to be used by any 777 "2 reds, 2 whites", whatever the body length, " This is debatable; requires the equivalent data for 777 as in #50, and context re PAPI - threshold distance i.e. rwy 22 and grass.
Runway length per se relates to the landing distance required, which is referenced to "15m (50 ft) above the landing surface", taken to be the nominal 'threshold'. AMC CS 25-1592
Certification accepts (appears to assume) that there will be some variation in TCH re 'use of procedures' and the nebulous 'pilots of average skill'; as indicated by the distribution of wheel touchdown positions.
PAPI is an angular guidance system indicating the required flight path angle.
An approach flown with constant 3Red or 3White will have an angular offset, but still guiding to the same position on the runaway. The TCH for approaches with one light deviation will have different TCH, but not significant wrt to the range of crossing altitudes in normal operations i.e. normal flight path variations (beware combinations of extremes - lower designed TCH, low approach + wind-shear).
An non-standard approach 3W becoming 4W, flown parallel to the approach path (pseudo long body) requires judgement of the longitudinal distance relative to PAPI as to where the change in indications occur (2W - 3W - 4W).
Without real-time computation the height displacement from the PAPI flight path is unknown - a judgement, which if excessive can result in a touchdown further down the runway, invalidating landing distance calculations (risk of overrun). A mis judged deliberate offset vs normal variability.
Increasing the distance between PAPI and the threshold (higher TCH):
If the PAPI was repositioned SW on the existing runway 22 then the TCH would be higher. This would not reduce landing distance available (same threshold); but the hazard of the lip between runway / grass still remains - possibility of wheel brake damage as discussed.
Retaining the current PAPI location but extending the runway by moving the threshold of 22 NE would again increase TCH, and ironically increase the LDA - new threshold, but again the hazard remains.
However, retaining the existing threshold and adding hardstanding to the NE should reduce the hazard - less likely to occur, compare with 27 wheel marks, but this may not reduce the perception of 'safety risk' from an early touchdown 27 vs 22 - already discussed.
Thus if 'it' can happen, 'it' will happen, and if 'it' happens on 22, then the higher safety risk from the hazard.
This is an issue for operational awareness, but not within pilots capability to reduce the risk; that's the 'hard' task for the airport - remove / reduce the hazard.
Bloggs #50
swh, thanks for the info; don't forget that with the correct TCH eye ht for the flt deck, the wheels are behind and lower, and lower still when they cross the threshold.
BraceBrace " The PAPI's are perfectly safe to be used by any 777 "2 reds, 2 whites", whatever the body length, " This is debatable; requires the equivalent data for 777 as in #50, and context re PAPI - threshold distance i.e. rwy 22 and grass.
"When the airplane is on a normal 3° glide path, the pilot sees two white lights on the left and two red lights on the right. The PAPI may be safely used in relation to threshold crossing height, but may result in landing further down the runway. The PAPI is normally aligned to intersect the runway 1,000 to 1,500 feet beyond the threshold."
If you want more info, the numbers are in the FCTM.
The "blocks" are 1300-1500ft from the threshold and work perfectly as aiming points from a visual approach. If you want to feel safe, you might use the "farther" edge, but you risk long landings, especially on a glider like the 777. I very very vaguely recall an approach where the approach plates indicate wide bodies have to consider "3 whites" on the PAPI's. But I suspect this is because people have been calculating the numbers on the ground and have found variations to the standard setup requiring the note.
If you want to argue, I suggest you contact the Boeing engineers. But I'm pretty sure they've already done the calculations you have been doing here.
From Boeing:
737-800 Eye height above wheel path: 17.1ft, giving a wheels over the threshold on 22 of 31ft, touchdown at 177m (no flare).
777-300 Eye height above wheel path: 33.5ft, giving a wheels over the threshold on 22 of 15ft, touchdown at 81m in (no flare). On the ILS, you're a little better off, with a wheel crossing height of 27ft and a no-flare touchdown point of 155m.
Theoretically, but in this case, the PAPI and the ILS are within 20m of each other, so they don't. One would happily fly down the 2W2R PAPI thinking "she'll be right' when in fact, if you go just a tad low for whatever reason, you're going to be very very close to scraping the keys.
737-800 Eye height above wheel path: 17.1ft, giving a wheels over the threshold on 22 of 31ft, touchdown at 177m (no flare).
777-300 Eye height above wheel path: 33.5ft, giving a wheels over the threshold on 22 of 15ft, touchdown at 81m in (no flare). On the ILS, you're a little better off, with a wheel crossing height of 27ft and a no-flare touchdown point of 155m.
Originally Posted by BraceBrace
The PAPI may be safely used in relation to threshold crossing height, but may result in landing further down the runway.
Originally Posted by BraceBrace
The PAPI is normally aligned to intersect the runway 1,000 to 1,500 feet beyond the threshold."
Quotes above come from Boeing. Pretty sure it's reliable.
Why care how close they are to eachother? Calibration and vertical positioning change everything. You might as well put a PAPI on a building next to the threshold, it will work fine if calibrated correctly. The PAPI provides a 62ft clearance according to the AIP, +/- 30ft to the wheels according to your document, giving a good 30ft clearance. I don't see the issue with the PAPI.
If you're low, you're low. You're not supposed to think you're fine. If you are "on" the PAPI, you will be fine. From the minima I have never heard anybody say you should "ride" the PAPI's to the ground. It's a visual maneuver with aiming point in the touchdown zone.
Theoretically, but in this case, the PAPI and the ILS are within 20m of each other, so they don't. One would happily fly down the 2W2R PAPI thinking "she'll be right' when in fact, if you go just a tad low for whatever reason, you're going to be very very close to scraping the keys.
If you're low, you're low. You're not supposed to think you're fine. If you are "on" the PAPI, you will be fine. From the minima I have never heard anybody say you should "ride" the PAPI's to the ground. It's a visual maneuver with aiming point in the touchdown zone.
Last edited by BraceBrace; 21st Jan 2023 at 17:47.
All that being said, despite the extra margin being provided by G/S Mini and the VAPP increments in strong headwinds, I've always found the Auto-Thrust, both on the A330 and A320 to let you down at the worst possible moment. It can often get itself out of sync with the gusts and the speed and result in an automatic form of PIO......
Personally I've always found manual thrust the best option on both the A320 and A330 when landing in blustery conditions, it allows better anticipation of speed drops and gains and allows for local knowledge to be applied, as is often known about different airports, such as passing a certain hangar or passing by a certain ditch. It allows you to maintain current thrust setting in areas where you know a gain in airspeed will be short lived and soon die off (whereas auto-thrust would reduce thrust and then whack it back on as the speed bleeds off) or in the case of Schipol, manual thrust allows you to anticipate the drop in speed you often get in the last 40-80 feet as you descend below the tree line.
Personally I've always found manual thrust the best option on both the A320 and A330 when landing in blustery conditions, it allows better anticipation of speed drops and gains and allows for local knowledge to be applied, as is often known about different airports, such as passing a certain hangar or passing by a certain ditch. It allows you to maintain current thrust setting in areas where you know a gain in airspeed will be short lived and soon die off (whereas auto-thrust would reduce thrust and then whack it back on as the speed bleeds off) or in the case of Schipol, manual thrust allows you to anticipate the drop in speed you often get in the last 40-80 feet as you descend below the tree line.
A320 Auto-Thrust performs reasonably well 90% of the time but the A330 auto-thrust in particular can often let you down for whatever reason, be it the larger engines and inertia, or just a different software gain/adjustment for counteracting airspeed reductions.
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