Narrative:

Several years ago; to reduce the possibility of a runway overrun accident; my air carrier modified its embraer rejected takeoff procedure. The procedure allowed a rejected takeoff between eighty knots and V1 only 'for an engine failure/fire or if the aircraft is unsafe to fly' (emb takeoff briefing). For less serious failures; the takeoff could continue; depending on the judgment of the crew (emb aborted takeoff procedures). The procedure has been modified a few times; but for the last few years; the option to continue a takeoff above eighty knots has been required only conditionally. This is sensible because the embraer rj does not usually require much runway for takeoff compared to other; heavier aircraft. For most takeoffs; the actual takeoff weight is well below the runway limited takeoff weight; which depends primarily on the available runway length. For most takeoffs; excess runway is available after an abort at or near V1. The method that my airline uses to determine whether to require the option to continue a takeoff above eighty KTS; however; is faulty. The procedure does not require the option in every appropriate case. Until recently; the determination involved a comparison of several takeoff weight limits (structural; runway; climb; drift down and landing plus enroute fuel); but did not include the actual takeoff weight. With the current procedure; the comparison is between only the aircraft's structural weight limit and the runway limited takeoff weight - again; not including the actual takeoff weight. The procedure is faulty because it occasionally permits a takeoff when the actual takeoff weight is very close to the runway limited takeoff weight - without requiring the option to continue a takeoff above eighty knots. Emb takeoff briefing says; 'anytime the runway limited takeoff weight is less than structural weight limit....after 80 KTS we will only abort for an engine failure/fire or if the aircraft is unsafe to fly.' here is an example of this determination using the emb 140 maximum structural takeoff weight - runway limited takeoff weight - 46;600 lb. Maximum structural takeoff weight - 46;517 lb. Actual takeoff weight - 46;400 lb. In this hypothetical; but not uncommon; example; the actual takeoff weight is only 200 pounds less than the runway limited takeoff weight. This condition warrants the option to continue a takeoff above eighty KTS. However; for the last few years the option has not been required by the procedure. Please refer to FAA advisory circular 120-62; dated september 12; 1994 and to the FAA publication; 'takeoff safety training aid;' published 'to help air carriers and pilots increase safety during the takeoff phase of flight.' see page 2.19; section 2.3.4.2 - actual weight less than limit weight; which says; in part; 'compare the actual airplane weight to the field length limit weight.... And 'by far; the most likely takeoff scenario for the line pilot is the case where the actual airplane weight is less than any limit weight; especially the field length limit weight. It also is possibly the most easily misunderstood area of takeoff performance since the fact that the airplane is not at a limit weight is about all the flight crew can determine from the data usually available on the flight deck. Currently; few operators provide any information that will let the crew determine how much excess runway is available; what it means in terms of the V1 speed they are using; or how to best maximize the potential safety margins represented by the excess runway.' the main thing to notice here is that the discussion involves a comparison between the actual airplane weight and the field length limit weight. See page 2.34; section 2.3.5.8 - the takeoff data the pilot sees. See page 2.35; which says; in part; 'it is essential that flight crews know their actual takeoff weight and that they use the proper takeoff speeds. It is equally important that the flight crew be aware of their proximity [my emphasis] to the limit weights for that takeoff's ambient conditions.' continuing; 'if the actual takeoff weight is equal to or near [my emphasis] the runway limit weight; the crew should note that fact and be extra alert that a reject from near [my emphasis] or at V1 will require prompt application of the full stopping capability of the airplane to assure stopping on the runway.' see page 2.39; section 2.3.6.9 the V1 call; which says a proposal for calling V1 is to use a call such as 'approaching V1' with the V1 portion occurring as the airspeed reaches V1 '[this] accomplishes the task of advising the flying pilot that the airplane is close to the speed where an rejected takeoff for all but the most serious failures is not recommended.' again; the method that the air carrier uses to determine whether to require the option to continue a takeoff above eighty KTS (analogous to the 'approaching V1' suggestion above) is faulty. The procedure does not require the option in every appropriate case. The simplest solution would be to require the option to continue a takeoff above eighty KTS for every takeoff; regardless of any weights or weight limits. (However; this may result in unnecessarily continuing a takeoff at a very light actual takeoff weight and/or very long available runway. This is; I think; a question to be considered separately.) another solution would be to require the option to continue a takeoff above eighty knots whenever the actual takeoff weight is within; for example; 1000 pounds of the runway limited takeoff weight. This determination would not be a difficult task for the crew since those two weights are already referenced for every takeoff. Using the above example of runway limited takeoff weight of 46;600 pounds; the option to continue a takeoff above eighty KTS would be required if the actual takeoff weight is greater than 45;600 pounds. To put this in a more real-world context; several times I have made a takeoff in the emb 140; rolled down the runway and very obviously 'used it up.' the airplane was relatively heavy and/or the runway was relatively short. The entire runway was required for the takeoff. However; the emb procedure did not require me to brief that I had the option to continue the takeoff with a less than serious failure after passing eighty KTS. This is a potential safety issue at our air carrier that could potentially be a contributing factor in a runway overrun accident.

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Original NASA ASRS Text

Title: An Air Carrier Pilot suggested modifying the standard rejected takeoff procedure above 80 knots to include permitting a reject anytime the aircraft's weight is at a light enough that runway length is not a limiting factor.

Narrative: Several years ago; to reduce the possibility of a runway overrun accident; my Air Carrier modified its Embraer rejected takeoff procedure. The procedure allowed a rejected takeoff between eighty knots and V1 only 'for an engine failure/fire or if the aircraft is unsafe to fly' (EMB Takeoff Briefing). For less serious failures; the takeoff could continue; depending on the judgment of the crew (EMB Aborted Takeoff Procedures). The procedure has been modified a few times; but for the last few years; the option to continue a takeoff above eighty knots has been required only conditionally. This is sensible because the Embraer RJ does not usually require much runway for takeoff compared to other; heavier aircraft. For most takeoffs; the actual takeoff weight is well below the runway limited takeoff weight; which depends primarily on the available runway length. For most takeoffs; excess runway is available after an abort at or near V1. The method that my Airline uses to determine whether to require the option to continue a takeoff above eighty KTS; however; is faulty. The procedure does not require the option in every appropriate case. Until recently; the determination involved a comparison of several takeoff weight limits (structural; runway; climb; drift down and landing plus enroute fuel); but did not include the actual takeoff weight. With the current procedure; the comparison is between only the aircraft's structural weight limit and the runway limited takeoff weight - again; not including the actual takeoff weight. The procedure is faulty because it occasionally permits a takeoff when the actual takeoff weight is very close to the runway limited takeoff weight - without requiring the option to continue a takeoff above eighty knots. EMB Takeoff Briefing says; 'Anytime the Runway Limited Takeoff Weight is less than Structural Weight Limit....after 80 KTS we will only abort for an engine failure/fire or if the aircraft is unsafe to fly.' Here is an example of this determination using the EMB 140 maximum structural takeoff weight - Runway limited takeoff weight - 46;600 lb. Maximum structural takeoff weight - 46;517 lb. Actual takeoff weight - 46;400 lb. In this hypothetical; but not uncommon; example; the actual takeoff weight is only 200 LBS less than the runway limited takeoff weight. This condition warrants the option to continue a takeoff above eighty KTS. However; for the last few years the option has not been required by the procedure. Please refer to FAA Advisory Circular 120-62; dated September 12; 1994 and to the FAA publication; 'Takeoff Safety Training Aid;' published 'to help air carriers and pilots increase safety during the takeoff phase of flight.' See page 2.19; Section 2.3.4.2 - Actual Weight Less Than Limit Weight; which says; in part; 'compare the actual airplane weight to the Field Length Limit Weight.... and 'By far; the most likely takeoff scenario for the line pilot is the case where the actual airplane weight is less than any limit weight; especially the Field Length Limit Weight. It also is possibly the most easily misunderstood area of takeoff performance since the fact that the airplane is not at a limit weight is about all the flight crew can determine from the data usually available on the flight deck. Currently; few operators provide any information that will let the crew determine how much excess runway is available; what it means in terms of the V1 speed they are using; or how to best maximize the potential safety margins represented by the excess runway.' The main thing to notice here is that the discussion involves a comparison between the actual airplane weight and the Field Length Limit Weight. See page 2.34; Section 2.3.5.8 - The Takeoff Data The Pilot Sees. See page 2.35; which says; in part; 'It is essential that flight crews know their actual takeoff weight and that they use the proper takeoff speeds. It is equally important that the flight crew be aware of their PROXIMITY [my emphasis] to the limit weights for that takeoff's ambient conditions.' Continuing; 'If the actual takeoff weight is equal to or NEAR [my emphasis] the runway limit weight; the crew should note that fact and be extra alert that a reject from NEAR [my emphasis] or at V1 will require prompt application of the full stopping capability of the airplane to assure stopping on the runway.' See page 2.39; Section 2.3.6.9 The V1 Call; which says a proposal for calling V1 is to use a call such as 'Approaching V1' with the V1 portion occurring as the airspeed reaches V1 '[This] accomplishes the task of advising the flying pilot that the airplane is close to the speed where an rejected takeoff for all but the most serious failures is not recommended.' Again; the method that the Air Carrier uses to determine whether to require the option to continue a takeoff above eighty KTS (analogous to the 'approaching V1' suggestion above) is faulty. The procedure does not require the option in every appropriate case. The simplest solution would be to require the option to continue a takeoff above eighty KTS for every takeoff; regardless of any weights or weight limits. (However; this may result in unnecessarily continuing a takeoff at a very light actual takeoff weight and/or very long available runway. This is; I think; a question to be considered separately.) Another solution would be to require the option to continue a takeoff above eighty knots whenever the actual takeoff weight is within; for example; 1000 LBS of the runway limited takeoff weight. This determination would not be a difficult task for the crew since those two weights are already referenced for every takeoff. Using the above example of runway limited takeoff weight of 46;600 LBS; the option to continue a takeoff above eighty KTS would be required if the actual takeoff weight is greater than 45;600 LBS. To put this in a more real-world context; several times I have made a takeoff in the EMB 140; rolled down the runway and very obviously 'used it up.' The airplane was relatively heavy and/or the runway was relatively short. The entire runway was required for the takeoff. However; the EMB procedure did not require me to brief that I had the option to continue the takeoff with a less than serious failure after passing eighty KTS. This is a potential safety issue at our Air Carrier that could potentially be a contributing factor in a runway overrun accident.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.