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What are the possible effects when an aircraft exceeds its approach speed limitations? i.e. unstable approach? Go around? Runway overrun I know a lot of factors come into play, however, I wish to determine the worst possible scenario

Marshallino Coetzee
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    What limitations are you thinking of? As approach speed is normally based on aircraft mass, there isn’t a fixed upper limit on approach speed per se. Other limits come into play, for example flap limit speeds etc. – Cpt Reynolds Jul 12 '18 at 09:16
  • lets assume an aircraft has an approach speed of 200kts during final, the AFM indicates it should be 185kts- in FDA this deviation is recorded as a Red event - however landing is uneventful. What are the possible risks involved in this instance...i hope you understand – Marshallino Coetzee Jul 12 '18 at 09:37
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    "What happens if an aircraft lands too fast", is that basically what you are trying to ask? – Ben Jul 12 '18 at 09:54
  • @MarshallinoCoetzee In this case, I don’t believe 185 kts is an aircraft limit in true sense. For FDA, each operator has to agree on operational limits for event identification, in my company e.g. this is done in increments of 10 kts for most speed targets. The risks associated with exceeding these operational limits have to be identified performing a risk analysis. For approach speed, provided no AFM/AMM limits are exceeded, the risks to the aircraft are mainly centred around landing and stopping performance on the runway or, vice versa, the unfavourable outcome could be a runway excursion. – Cpt Reynolds Jul 12 '18 at 10:59
  • @CptReynolds in my company for example we do not alter the FDA parameters. the application we use is AirFASE and we use the default parameters build into the FAP for the specific aircraft/ fleet. Thanks for the help. It makes sense that stopping performance would be affected based on the RWY length for example, and RWY excursion would be the worst possible outcome if the brakes do not give n prior to this, then again if the high speed approach is not corrected, hard braking would be the next possible event trigger in FDA? Thanks again for the assistance!! – Marshallino Coetzee Jul 12 '18 at 12:38
  • @ben exactly my phrasing was a little off. LOL – Marshallino Coetzee Jul 12 '18 at 12:39
  • http://enroute.aircanada.com/en/articles/are-there-speed-limits-for-aircraft – Super Jul 12 '18 at 14:28
  • @MarshallinoCoetzee I don’t believe we have a “hard braking” trigger, as hard braking may well be quite right in some cases. What I would trigger for on landing is “long flare/late touchdown” (e.g. distance/time from 50ft to weight on wheels), “high speed at touchdown” (based on difference from normal ops or standard procedures), “high speed at stop end” (i.e. xx kts with less than yy meters LDA remaining) and potentially things like “late deceleration” or similar, although that is in itself another contributor to runway excursion risk not to do with approach speed. – Cpt Reynolds Jul 12 '18 at 19:38
  • @Cpt Reynolds i have seen a parameter "questionable breaking at landing" i guess this would have nothing to do with the high appr speeds? Thanks again for the information shared – Marshallino Coetzee Jul 13 '18 at 15:35
  • If for example the high appr speed event is airport specific can the flow of traffic by ATC attribute to the event in FDA? I also interpret the aircraft FCOM SOPs which we have adopted, as saying it is acceptable as long as the speed slows down to the managed speed?? – Marshallino Coetzee Jul 13 '18 at 16:16
  • @MarshallinoCoetzee I would argue that if high approach speed event is regularly triggered by ATC speed restrictions (e.g. 160kts to 4DME as in LHR), the event trigger needs to change to reflect the normal operational environment - unless of course there is a company procedure to not adhere to that ATC instruction... – Cpt Reynolds Jul 13 '18 at 17:47
  • @MarshallinoCoetzee I don’t think „questionable braking“ has much to do with approach speed; however I am not certain. My gut feel is it’s rather too little braking than too much, but I really don’t know; we don’t have that trigger - at least not under this description. I hope you don’t mind, but can I please observe I‘d recommend to rename it using an objective description of what it triggers on, rather than the word „questionable“ which could be construed to imply judgement passed on flight crew action? – Cpt Reynolds Jul 13 '18 at 19:06
  • @CptReynolds modifying the event trigger would then encompass all operations...the event is only specific to a certain airport where traffic is high, esp during our slot times, thus i do not think modifying the parameter is recommended...? Upon further investigation I realized it is our smaller fleet which have this problem upon landing and mainly due to ATC request for an earlier turn off during taxi... unfortunately i am not allowed for "you to observe" - company policy - I trust you understand. The comments, however, have given me a broader understanding. Thank you indeed! – Marshallino Coetzee Jul 16 '18 at 14:00
  • @MarshallinoCoetzee Oh, I didn’t mean I wanted to see any data or so - it’s just a figure of speech. My fault. I only wanted to recommend the renaming! – Cpt Reynolds Jul 16 '18 at 14:47
  • @CptReynolds no worries. thank you in any case for sharing your knowledge and undoubted experience. Rgrds – Marshallino Coetzee Jul 17 '18 at 13:58

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