Why need Toga for taking off after deiceing.
Joined: Mar 2006
Posts: 1,115
Likes: 86
From: England
De-icing fluid on the aircraft is a contaminant which can change the aircraft takeoff performance. Test flights many years ago (early 737 ?) indicated that the loss of performance was not significant with respect to the margins in the performance calculations.
A few years ago with the introduction of ‘thicker’ type 4 fluids, created unforeseen problems with ‘gelling’ or dry out because the wing voids retained residual fluid. As part of these investigations, test flights indicated that the performance loss of some aircraft would be higher than previously assumed due to the fluid remaining on the wing much longer. Thus additional procedures were required.
Also, for some aircraft types flight handling characteristics changed, which required special procedures, configuration, or performance.
#1 does not give the aircraft type, thus the use of TOGA could be type specific, either for performance reasons or flight handling.
From memory turboprops had more restrictions than jets.
This question might also be connected with no flex power on contaminated runways.
A few years ago with the introduction of ‘thicker’ type 4 fluids, created unforeseen problems with ‘gelling’ or dry out because the wing voids retained residual fluid. As part of these investigations, test flights indicated that the performance loss of some aircraft would be higher than previously assumed due to the fluid remaining on the wing much longer. Thus additional procedures were required.
Also, for some aircraft types flight handling characteristics changed, which required special procedures, configuration, or performance.
#1 does not give the aircraft type, thus the use of TOGA could be type specific, either for performance reasons or flight handling.
From memory turboprops had more restrictions than jets.
This question might also be connected with no flex power on contaminated runways.
Joined: Aug 2013
Posts: 45
Likes: 0
From: blue planet
De-icing fluid on the aircraft is a contaminant which can change the aircraft takeoff performance. Test flights many years ago (early 737 ?) indicated that the loss of performance was not significant with respect to the margins in the performance calculations.
A few years ago with the introduction of ‘thicker’ type 4 fluids, created unforeseen problems with ‘gelling’ or dry out because the wing voids retained residual fluid. As part of these investigations, test flights indicated that the performance loss of some aircraft would be higher than previously assumed due to the fluid remaining on the wing much longer. Thus additional procedures were required.
Also, for some aircraft types flight handling characteristics changed, which required special procedures, configuration, or performance.
#1 does not give the aircraft type, thus the use of TOGA could be type specific, either for performance reasons or flight handling.
From memory turboprops had more restrictions than jets.
This question might also be connected with no flex power on contaminated runways.
A few years ago with the introduction of ‘thicker’ type 4 fluids, created unforeseen problems with ‘gelling’ or dry out because the wing voids retained residual fluid. As part of these investigations, test flights indicated that the performance loss of some aircraft would be higher than previously assumed due to the fluid remaining on the wing much longer. Thus additional procedures were required.
Also, for some aircraft types flight handling characteristics changed, which required special procedures, configuration, or performance.
#1 does not give the aircraft type, thus the use of TOGA could be type specific, either for performance reasons or flight handling.
From memory turboprops had more restrictions than jets.
This question might also be connected with no flex power on contaminated runways.
Joined: Sep 2002
Posts: 2,188
Likes: 6
From: La Belle Province
Yes, Principally aircraft with lower than typical jet rotation speeds. Because the fluid flow-off characteristics are determined with a generic speed ramp test (but ul;timately tracing back to the 737-200 ADV!), and pass/fail for a fluid is based on that acceleration profile, any aircraft that falls significantly below that profile may fail to shed fluids as "normal" and may need more speed, either to promote more shedding or to compensate for the failure to shed, or both.
Joined: Jun 2001
Posts: 480
Likes: 27
From: at the edge of the alps
