Practically stopping

Converting to a new aircraft is fun because it is a licence to be a learner for a while. In January I completed my training back to the Airbus A320 family of aircraft. The flying is fun but the baby Airbus is overly complicated by an obsession with unachievable precision and theory.

Precision is laudable, don’t get me wrong; a sloppy pilot is never a good pilot. But there has to be a limit and that limit is most usually defined by practicality. Practicality featured very heavily in the old Boeing 767 operation that I was once familiar with. I know that the Boeing Co has taken this pragmatic approach forwards to the 777 and 787.

The philosophy as far as a pilot is concerned is “if you can’t influence or change it, we won’t go into depth about it.”. This is a pretty good maxim for life in general. But, if your capacity is already used up by the complex business of flying a jet airliner and managing a crew and the immediate environment then it makes for a great starting point. Simple is good.

The general perception of airliner flying is that it is very precise, very scientific, and entirely measurable. Sure, this is true of very many aspects of the kind of flying that I do. But huge sections of flying share the very peculiar attribute of being absolutely and very precisely approximate.

Take the business of landing for example. The approach, the description of the flare (the manoeuvre that slows the descent rate just prior to touchdown) technique, go-around action sequences and so on can all be described precisely. The actual business of flaring an aircraft is a bit like throwing and catching a ball: if you tried to describe how you aim, release, scoop up the ball precisely you would use up all of the words on the planet and still not manage an accurate account.

Until relatively recently one aspect that ought to have been very precise were landing performance calculations. After all, we calculate the takeoff performance to the foot, metre, knot and kilo so why should landing be any different?

After a series of close calls and accidents it turned out that landing performance was both difficult to practically calculate and that it was even harder to realistically achieve. Most airlines and operators treated landing performance as a bit of a planning exercise rather than an assessment of the conditions on the day.

For most pilots, actually predicting a landing was a black art and usually relied on your last trip to that airport. The science ceased and out came the seaweed and wetted finger to figure whether the tarmac was ‘a bit short’ or ‘long enough’. The common notion was that landing distance information was ‘unachievable in the real world’.

Published figures were “…test pilot stuff…”. That was what I heard many times. The truth was that the numbers weren’t even that: they were typically a composite of the three ‘best’ (shortest) landing distances achieved in certification. The best final few feet, the best flare, the best rollout. Thereafter a load of theory and extrapolation made up the numbers. In general it was suggested that if you made the numbers in the book you wouldn’t be able to use the aircraft again and somebody would have to sweep up the bits of brake component and straighten out all of the wrinkles.

The good news is that the published numbers have changed. The TALPA ARC group drove a top to bottom review of the whole process. The objective was to give pilots in the live environment a set of information which could reliably predict the business of landing and stopping. Now, these figures are available to airlines that want to embrace this safer (but more restrictive) methodology. They turn what used to be absolute and impossible precision into something more tangible.

This isn’t just about the numbers in the book. All of the conditions which lead in to the landing itself are critical: the approach stability, the runway state reporting, the flare technique, brake (and autobrake) handling methods, lateral positioning all have working parameters which lead to a good outcome.

My lessons this week have been the fruits of spending time calculating expected landing performance, flying very precisely and as close to the written techniques as possible then reviewing where we stopped and whether my technique was what it should have been.

This process of ‘plan, fly, review’ is the key to improvement and it can apply to your whole operation, not just landing performance. What’s my plan for today? How will I achieve it? How did it go? It can be a pretty brutal experience; like looking in one of those magnifying mirrors in a hotel bathroom with a big light around it. But it really is the only way to develop.

Despite the complexity of the Airbus ‘performance’ section of the QRH (quick reference handbook) and the clunky and unrewarding nature of the Airbus autobrake system it turns out that the numbers are good. I can now feel more confident that I can generate safe, reliable and repeatable landing performance in all sorts of conditions. The big challenge is to get the pilot community more plugged in to the business of landing performance calculation. The culture is slowly changing, being led by solid policy making at an airline level, but to come to life it needs to become just what we do, every time. Even when nobody is looking over our shoulders.


3 thoughts on “Practically stopping

  1. Interesting, I also went from the B757/767 to the baby bus and saw some performance figures that were “interesting” . We operated to one airfield where the 320 V1 was 159( ish, it’s a while back) but the Vref at the same weight was low 130’s, A good question for the newer f/o was would you land 3/4 of the way down the runway at Vref +20? Discuss!
    The FAA are very hot on working out landing distance on check rides at the moment and proving that you can stop in the calculated distance.

    • Hi Bob. Yes, Airbus takeoff numbers are rarely directly correlated to V2/Vs1g because of the takeoff optimisation method used (effectively a variable improved climb, unlike Boeing binary choice)

      The important piece for me is knowing expected retardation rate and therefore being able to make an early assessment of runway state… maybe more on this in another post?

      • Definitely, getting a feel for what looks and feels right- be it the numbers or acceleration/retardation- is a valuable skill.
        It takes a while on any new type be it a Cub or a big jet and it’s something I always ask about when checking out.

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