TACA aircraft crashed in Honduras
Bernd, thank you for the clarification. Indeed responsibility for clarification appears to be in the first instance with Airbus, and perhaps second, with the regulators; - my poor choice of words in not leaving these options open. Re ‘qualified’ – in the sense of not being explained in sufficient detail or in context – bounded or limited.
IMHO a manufacturer’s recommendation provides guidance and is not a limit, but I recognise that many interpretations (including some regulators) mandate recommendations.
I still don’t follow the description of the ‘immediate’ activation of brakes with MAX, nor de-rotation (what about low torque with antiskid on a low friction runway?), but this not for discussion here.
The Airbus advice ‘to use MED braking’ (MAX not recommended) could be interpreted in a way which might reduce the safety margin during landing. Consider the following:-
Landing distance is based on the unfactored distance plus a safety margin.
The unfactored distance is a theoretical minimum, using maximum braking etc, etc.
The safety margin … “accounts for the normal operational variability that can be expected in day to day service such that the chances of a landing overrun are remote.” ( UK AIC 14/2006)
Some of the safety margin may be used in ‘normal braking’ … “Passenger comfort and brake wear considerations generally induce a reluctance to utilise the aeroplane's full braking potential. This is acceptable where other factors affecting stopping performance are favourable, for example when the braking action is good, and when the landing distance available is clearly not limiting. However, reduced braking will result in the erosion of the factors built into the scheduled landing distances and is not appropriate where the margin has been eroded for other reasons. ”
The second quote covers the key issues of limiting distance and eroded safety margin, e.g. tailwind limited distance / poor braking action.
If auto brake MED is equated to ‘reduced braking’, then the Airbus recommendation appears to lack any advice about other situations such as operating with limiting landing distances. In this instance a clear instruction to use manual brake in unfavourable conditions might be appropriate to alert crews to evaluate the need to change procedures. Perhaps this is documented elsewhere, or considered to be knowledge within ‘airmanship’ – an assumption (mine, the manufacturer, the industry?).
IMHO the AIC text provides a clear rationale of when not to use ‘reduced braking’, i.e. when not to use auto brake settings other than MAX. If pilots, do not interpret the Airbus advice in this way (nothing says that they should), then the continued use of MED auto brake in unfavourable conditions might reduce the overall margin of safety during landing, and furthermore mask or delay the identification of a deteriorating condition as discussed previously.
This view identifies with the operating differences between Airbus and Boeing (or other auto-brake aircraft), where MAX can or cannot be used ‘routinely’ (a consideration in decision making).
Perhaps the origins of this problem are beyond the immediate FCOM documentation, and come from training or guidance in SOPs; either of these can lead to bias in decision making or an inappropriate mind set based on the habits of normal operations.
A solution, in addition to clarifying procedures, might be to consider how to transfer knowledge, particularly the ‘know how’ which forms experience as related by – NVpilot (#381), FlexibleResponse (#392)
Such are the problems of explanatory materials, recommendations, assumptions, and the choice of words.
IMHO a manufacturer’s recommendation provides guidance and is not a limit, but I recognise that many interpretations (including some regulators) mandate recommendations.
I still don’t follow the description of the ‘immediate’ activation of brakes with MAX, nor de-rotation (what about low torque with antiskid on a low friction runway?), but this not for discussion here.
The Airbus advice ‘to use MED braking’ (MAX not recommended) could be interpreted in a way which might reduce the safety margin during landing. Consider the following:-
Landing distance is based on the unfactored distance plus a safety margin.
The unfactored distance is a theoretical minimum, using maximum braking etc, etc.
The safety margin … “accounts for the normal operational variability that can be expected in day to day service such that the chances of a landing overrun are remote.” ( UK AIC 14/2006)
Some of the safety margin may be used in ‘normal braking’ … “Passenger comfort and brake wear considerations generally induce a reluctance to utilise the aeroplane's full braking potential. This is acceptable where other factors affecting stopping performance are favourable, for example when the braking action is good, and when the landing distance available is clearly not limiting. However, reduced braking will result in the erosion of the factors built into the scheduled landing distances and is not appropriate where the margin has been eroded for other reasons. ”
The second quote covers the key issues of limiting distance and eroded safety margin, e.g. tailwind limited distance / poor braking action.
If auto brake MED is equated to ‘reduced braking’, then the Airbus recommendation appears to lack any advice about other situations such as operating with limiting landing distances. In this instance a clear instruction to use manual brake in unfavourable conditions might be appropriate to alert crews to evaluate the need to change procedures. Perhaps this is documented elsewhere, or considered to be knowledge within ‘airmanship’ – an assumption (mine, the manufacturer, the industry?).
IMHO the AIC text provides a clear rationale of when not to use ‘reduced braking’, i.e. when not to use auto brake settings other than MAX. If pilots, do not interpret the Airbus advice in this way (nothing says that they should), then the continued use of MED auto brake in unfavourable conditions might reduce the overall margin of safety during landing, and furthermore mask or delay the identification of a deteriorating condition as discussed previously.
This view identifies with the operating differences between Airbus and Boeing (or other auto-brake aircraft), where MAX can or cannot be used ‘routinely’ (a consideration in decision making).
Perhaps the origins of this problem are beyond the immediate FCOM documentation, and come from training or guidance in SOPs; either of these can lead to bias in decision making or an inappropriate mind set based on the habits of normal operations.
A solution, in addition to clarifying procedures, might be to consider how to transfer knowledge, particularly the ‘know how’ which forms experience as related by – NVpilot (#381), FlexibleResponse (#392)
Such are the problems of explanatory materials, recommendations, assumptions, and the choice of words.
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Dream Land:
Thank you! I was beginning to wonder if I really was missing some vital information certain others seemed to have. 
I would have thought that closing the thrust levers when landing is a no brainer, I can assure you that no one is bringing up the 15 degree TLA in training and there is no real need to know this, also it's not a factor in any of the landing incidents.
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HEAD OF HONDURAN CIVIL AVIATION CHARGED FOR ILLEGAL LICENCES
Honduras’ Attorney General ordered on Tuesday 12, 2008 to apprehend Guillermo Seamman, director-general of the National Civil Aviation Authority (DGAC), who has been charged of issuing 38 illegal licenses to pilots and mechanics from Venezuela y Peru. “Seamman is accused of abusing power and thus an apprehension warrant has been issued”, said Public Ministry spokesman Melvin Duarte. After several months of investigation, the Attorney General’s Office on Organized Crime “determined that Seamann endorsed licenses to pilots, aviation mechanics, air hostesses and flight attendants”, he added. Those benefited, including 38 Venezuelans and one Peruvian, obtained their documents “without having to come to Honduras of having to pass the corresponding tests. They did it through local lawyers… and that is illegal. Seamman, who was appointed by President Manuel Zelaya in 2006 to lead DGAC for 4 years, denied the charges and told Radio Cadena Voces that “everything was done correctly”, although he did not deny signing the licenses. The International Civil Aviation Organization (ICAO) certified Toncontín as an international airport, but it could take time to endorse DGAC following the accusation.
Honduras’ Attorney General ordered on Tuesday 12, 2008 to apprehend Guillermo Seamman, director-general of the National Civil Aviation Authority (DGAC), who has been charged of issuing 38 illegal licenses to pilots and mechanics from Venezuela y Peru. “Seamman is accused of abusing power and thus an apprehension warrant has been issued”, said Public Ministry spokesman Melvin Duarte. After several months of investigation, the Attorney General’s Office on Organized Crime “determined that Seamann endorsed licenses to pilots, aviation mechanics, air hostesses and flight attendants”, he added. Those benefited, including 38 Venezuelans and one Peruvian, obtained their documents “without having to come to Honduras of having to pass the corresponding tests. They did it through local lawyers… and that is illegal. Seamman, who was appointed by President Manuel Zelaya in 2006 to lead DGAC for 4 years, denied the charges and told Radio Cadena Voces that “everything was done correctly”, although he did not deny signing the licenses. The International Civil Aviation Organization (ICAO) certified Toncontín as an international airport, but it could take time to endorse DGAC following the accusation.
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From the news, I can see that pilot licenses in Honduras were obtained by mail order direct from the local CAA, and most probably against their own regulations. I have a couple questions, just to start:
Who were the ones that obtained such a benefit?
Does that include TACA personnel?
I know many other questions will come to light, that includes all of the government aviation related offices.
Who were the ones that obtained such a benefit?
Does that include TACA personnel?
I know many other questions will come to light, that includes all of the government aviation related offices.
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Honduras has their own way of dealing with legalities. I am happy to see that the US carriers are now flying into TGU and safely landing every day as before. It is a good thing that TGU is open to jets again. Hopefully the jets flying into TGU will abide by the rules this time. No more landing downhill on a wet runway with a 10 knot tailwind like TACA did.
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"On Feb 22nd 2017 The Aviation Herald was able to obtain a copy of the final report, which carries no date of when it was published. El Salvador's Civil Aviation Authority (AAC) website to date still only offers the preliminary report, the final report was never released onto the website. The Aviation Herald is unable to publish the final report due to personal remarks present on the scan of the paper report.
The final report concludes the causes of the accident were:
The investiation determined that the probable cause of this accident was the decision to land on a runway without proper assessment of the operational conditions, weather, aircraft's landing weight and runway conditions and disregarding the operator procedure, while missing essential information on the runway conditions.
Contributory Causes:
- the landing was long, probably due to the tailwind and high energy of the aircraft with a ground speed around 160 knots.
- the operating crew did not recalculate the maximum landing weight permissable and the actual landing distance prior to commencing the approach.
- the non-precision approach with a subsequent circle to a visual landing was conducted in poor weather conditions, which resulted in high cockpit workloads.
- the manufacturer provided procedure does not provide guidance on applicable actions for a touchdown beyond the recommended touchdown zone.
- contributing to the severity of the accident was the lack of a stopway and a cliff at the end of runway 02.
- contributing to the reduced braking efficiency was the lack of pavement grooving, which resulted in inadequate runway drainage.
The AAC reported the captain (40, ATPL, 11,899 hours total, 8,514 hours on type) was pilot flying, he had completed 52 landing at Tegucigalpa's Toncontin Airport before the accident flight. The first officer (26, ATPL, 1,607 hours total, 250 hours on type) was pilot monitoring and had completed 5 landings at Toncontin prior to the accident flight.
Due to winds reported from 200 degrees at 6 knots the aircraft performed an approach to runway 20, a VOR/DME approach to runway 02 circling runway 20, however, when about to begin the circling for runway 20 the captain decided he couldn't perform the circling due to low visibility and went around. The aircraft climbed to 8000 feet and joined a hold over the Tegucigalpa VOR. The captain decided that despite the tailwind (recommended limit for Toncontin at 5 knots) they would land on runway 02, if the wind was 5 knots or less, as landing on runway 20 was not possible due to a low clouds obscuring the hills around the aerodrome.
The crew contacted dispatch asking whether they should divert to San Pedro Sula in case of another go around.
The aircraft positioned for another VOR/DME approach to runway 02, upon being handed off to tower requested to circle to land on runway 02. Tower queried the crew reporting winds from 200 degrees at 10 knots. The crew repeated the request to land on runway 02 reasoning that circling to runway 20 was not possible due to visibility. Tower accepted the request and reported the winds from 190 degrees at 10 knots, then cleared the aircraft to land on runway 02 advising the runway was damp.
At 15:45:12Z the aircraft, flaps were set at 40 degrees/full, touched down 400 meters past the runway threshold at 160 knots over ground and 135 KIAS, the spoilers and reversers were deployed, maximum reverse thrust selected, the crew felt the aircraft did not slow, about 4 seconds after touchdown the crew began to apply manual brakes disengaging the automatic brakes, the brakes pressure was released in between, then the brakes pressure rose up to maximum pressure, in the first 2 seconds after reaching the maximum brakes pressure the aircraft rolled 150 meters (145 knots over ground), the aircraft experienced about 0.3-0.45G deceleration reaching the maximum between 15:45:22 and 15:45:27Z, the first officer eventually called "70 knots", 70 KIAS with 90 knots over ground, at 15:45:27Z, the reversers were disengaged (forward idle thrust), due to lack of deceleration the first officer disenages anti-skid and now feels deceleration. and overran the end of the runway at 15:45:35Z, dropped down a cliff of 75 feet height onto a public road and two cars, hit a concrete pole carrying power lines, the pole penetrated the right wing root and started a fire. A fire truck, who passed by the accident site at that time, immediately began to extinguish the fire thus allowing the surviving passengers to be rescued.
The captain and two passengers died in the accident, two occupants of the cars crushed by the aircraft died, 39 people received serious injuries and 93 persons survived with minor or no injuries. The aircraft was destroyed.
The AAC reported that there was no runway friction measurement prior or after the accident. The Jeppesen Approach plates warned that the runway was slippery when wet. The runway had been re-surfaced prior to the accident and was not grooved at the time of the accident. Runway 02 has a landing distance available of 1649 meters (5410 feet) due to the displaced threshold, runway 02 has a downslope of 0.88%.
The AAC reported that examination of the braking system showed no malfunction or anomaly, all brakes were within normal wear. There were no leakages.
Examination of the tyres #1, #2 and #3 revealed tyre damage consistent with blocked wheels on a wet surface, likely occurring after the anti-skid was disengaged. Tyre #4 showed no such damage consistent with a blocked wheel.
The AAC reported that the aircraft landed with a gross mass of 64,389 kg. Landing on a dry runway 02 with no winds and flaps full would have permitted up to 66,300kg, on a wet runway a maximum weight of 59,700kg was possible (no wind). For the actual landing weight and runway condition the landing distance required, as computed by the AAC, was 1807 meters with a landing distance available of 1649 meters. The AAC warned - see in the analysis - that this was not a practical number but a certification figure.
The AAC analysed that when tower cleared the flight to land on runway 02 reporting winds from 190 degrees at 10 knots, the aircraft should have gone around considering the recommended tail wind limit was 5 knots.
The AAC analysed that the aircraft touched down 400 meters past the (displaced) runway threshold and about 150 meters past the first perpendicular taxiway. According to Airbus procedures for a wet runway a landing should be discontinued if the touchdown does not occur at or before the first perpendicular taxiway.
The AAC analysed that even if anti-skid had not been deactivated, the aircraft would have overrun the end of the runway.
The AAC analysed that the aircraft, touching down at the same touchdown point as during the accident flight, could have stopped 68 meters before the runway end had the crew derotated the nose in 3 instead of 7 seconds, initiated braking 2 seconds and reaching maximum braking 3 seconds after main gear touchdown instead of 4 and 14 seconds, maximum reverse 1 second after touchdown (identical to accident flight), idle reverse thrust at 70 KIAS, maximum pedal brakes until full stop.
The AAC analysed that the landing distances determined during the aircraft certification are aimed at demonstrating the shortest possible landing distance for a given landing weight with a test pilot at the controls and are established with full awareness that operational rules for normal operations require additional factors to be added for determining minimal operational field lengths. If pilots are unaware of these considerations, they might believe that they need less landing distance than they actually do or have an inaccurate perceiption of how much braking effort will be needed on landing."
Crash: TACA A320 at Tegucigalpa on May 30th 2008, overran runway and crashed into embankment
The final report concludes the causes of the accident were:
The investiation determined that the probable cause of this accident was the decision to land on a runway without proper assessment of the operational conditions, weather, aircraft's landing weight and runway conditions and disregarding the operator procedure, while missing essential information on the runway conditions.
Contributory Causes:
- the landing was long, probably due to the tailwind and high energy of the aircraft with a ground speed around 160 knots.
- the operating crew did not recalculate the maximum landing weight permissable and the actual landing distance prior to commencing the approach.
- the non-precision approach with a subsequent circle to a visual landing was conducted in poor weather conditions, which resulted in high cockpit workloads.
- the manufacturer provided procedure does not provide guidance on applicable actions for a touchdown beyond the recommended touchdown zone.
- contributing to the severity of the accident was the lack of a stopway and a cliff at the end of runway 02.
- contributing to the reduced braking efficiency was the lack of pavement grooving, which resulted in inadequate runway drainage.
The AAC reported the captain (40, ATPL, 11,899 hours total, 8,514 hours on type) was pilot flying, he had completed 52 landing at Tegucigalpa's Toncontin Airport before the accident flight. The first officer (26, ATPL, 1,607 hours total, 250 hours on type) was pilot monitoring and had completed 5 landings at Toncontin prior to the accident flight.
Due to winds reported from 200 degrees at 6 knots the aircraft performed an approach to runway 20, a VOR/DME approach to runway 02 circling runway 20, however, when about to begin the circling for runway 20 the captain decided he couldn't perform the circling due to low visibility and went around. The aircraft climbed to 8000 feet and joined a hold over the Tegucigalpa VOR. The captain decided that despite the tailwind (recommended limit for Toncontin at 5 knots) they would land on runway 02, if the wind was 5 knots or less, as landing on runway 20 was not possible due to a low clouds obscuring the hills around the aerodrome.
The crew contacted dispatch asking whether they should divert to San Pedro Sula in case of another go around.
The aircraft positioned for another VOR/DME approach to runway 02, upon being handed off to tower requested to circle to land on runway 02. Tower queried the crew reporting winds from 200 degrees at 10 knots. The crew repeated the request to land on runway 02 reasoning that circling to runway 20 was not possible due to visibility. Tower accepted the request and reported the winds from 190 degrees at 10 knots, then cleared the aircraft to land on runway 02 advising the runway was damp.
At 15:45:12Z the aircraft, flaps were set at 40 degrees/full, touched down 400 meters past the runway threshold at 160 knots over ground and 135 KIAS, the spoilers and reversers were deployed, maximum reverse thrust selected, the crew felt the aircraft did not slow, about 4 seconds after touchdown the crew began to apply manual brakes disengaging the automatic brakes, the brakes pressure was released in between, then the brakes pressure rose up to maximum pressure, in the first 2 seconds after reaching the maximum brakes pressure the aircraft rolled 150 meters (145 knots over ground), the aircraft experienced about 0.3-0.45G deceleration reaching the maximum between 15:45:22 and 15:45:27Z, the first officer eventually called "70 knots", 70 KIAS with 90 knots over ground, at 15:45:27Z, the reversers were disengaged (forward idle thrust), due to lack of deceleration the first officer disenages anti-skid and now feels deceleration. and overran the end of the runway at 15:45:35Z, dropped down a cliff of 75 feet height onto a public road and two cars, hit a concrete pole carrying power lines, the pole penetrated the right wing root and started a fire. A fire truck, who passed by the accident site at that time, immediately began to extinguish the fire thus allowing the surviving passengers to be rescued.
The captain and two passengers died in the accident, two occupants of the cars crushed by the aircraft died, 39 people received serious injuries and 93 persons survived with minor or no injuries. The aircraft was destroyed.
The AAC reported that there was no runway friction measurement prior or after the accident. The Jeppesen Approach plates warned that the runway was slippery when wet. The runway had been re-surfaced prior to the accident and was not grooved at the time of the accident. Runway 02 has a landing distance available of 1649 meters (5410 feet) due to the displaced threshold, runway 02 has a downslope of 0.88%.
The AAC reported that examination of the braking system showed no malfunction or anomaly, all brakes were within normal wear. There were no leakages.
Examination of the tyres #1, #2 and #3 revealed tyre damage consistent with blocked wheels on a wet surface, likely occurring after the anti-skid was disengaged. Tyre #4 showed no such damage consistent with a blocked wheel.
The AAC reported that the aircraft landed with a gross mass of 64,389 kg. Landing on a dry runway 02 with no winds and flaps full would have permitted up to 66,300kg, on a wet runway a maximum weight of 59,700kg was possible (no wind). For the actual landing weight and runway condition the landing distance required, as computed by the AAC, was 1807 meters with a landing distance available of 1649 meters. The AAC warned - see in the analysis - that this was not a practical number but a certification figure.
The AAC analysed that when tower cleared the flight to land on runway 02 reporting winds from 190 degrees at 10 knots, the aircraft should have gone around considering the recommended tail wind limit was 5 knots.
The AAC analysed that the aircraft touched down 400 meters past the (displaced) runway threshold and about 150 meters past the first perpendicular taxiway. According to Airbus procedures for a wet runway a landing should be discontinued if the touchdown does not occur at or before the first perpendicular taxiway.
The AAC analysed that even if anti-skid had not been deactivated, the aircraft would have overrun the end of the runway.
The AAC analysed that the aircraft, touching down at the same touchdown point as during the accident flight, could have stopped 68 meters before the runway end had the crew derotated the nose in 3 instead of 7 seconds, initiated braking 2 seconds and reaching maximum braking 3 seconds after main gear touchdown instead of 4 and 14 seconds, maximum reverse 1 second after touchdown (identical to accident flight), idle reverse thrust at 70 KIAS, maximum pedal brakes until full stop.
The AAC analysed that the landing distances determined during the aircraft certification are aimed at demonstrating the shortest possible landing distance for a given landing weight with a test pilot at the controls and are established with full awareness that operational rules for normal operations require additional factors to be added for determining minimal operational field lengths. If pilots are unaware of these considerations, they might believe that they need less landing distance than they actually do or have an inaccurate perceiption of how much braking effort will be needed on landing."
Crash: TACA A320 at Tegucigalpa on May 30th 2008, overran runway and crashed into embankment
Short, damp, ungrooved runway, with downhill slope, tailwind, non-precision approach (after already going around), low experience F/O, high landing weight.........
I don't understand this concept of asking if they should divert; the PIC should be telling dispatch that they are diverting. Whilst unfamiliar with the airport and the airline, I'd suggest that there might have been a few problems with the organisational culture.
The crew contacted dispatch asking whether they should divert to San Pedro Sula in case of another go around.
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And if you look at the video on the Aviation Herald that shows the aircraft briefly during its landing roll, it appears to be more than damp. Faulty info passed on by the controller possibly. It had been drizzling for a while, and could explain the braking issues encountered. Beware.
