PPRuNe Forums - View Single Post - Final Report: April 2018 737 high speed aborted TO
Old 17th Feb 2021, 14:42
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Stuka Child
 
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Thread recap for those who might have missed the important points or are purposefully ignoring them:

- Boeing guidance has always been that rejecting post-V1 is not recommended (which for the obviously English-speaking people who are pretending not to understand English is not the same thing as forbidden), but it remains at the Captain's discretion if the Captain judges the aircraft unsafe to fly*. As for airlines, not sure what outfit you fly for, but I have never seen it phrased as anything other than you are encouraged to continue after V1, but this is by no means a command to go at any cost. That little phrase "unsafe to fly" is always, always there, in order to give you the freedom to adapt to whatever crappy circumstances you might be faced with one day.

- For this particular incident, the report agreed with the Cpt's decision to abort, even though said decision was wrong in hindsight. Why did the investigators then give him the benefit of the doubt? Because he judged the aircraft unsafe to fly. Every Captain must make this decision on every takeoff, and unfortunately there is no clear guidance on what would help her or him decide what makes an aircraft unsafe to fly. This is where judgement is exercised*.

- A study examining high speed aborts found that 31.9% of decisions to reject after V1 were correct, 44.4% were incorrect and the rest debatable. That is to say, in 31.9% of these cases, continuing after V1 would have resulted in a crash. It is not the majority, but it is a lot, and it puts to sleep your theory that there is never a reason to stop after V1. I don't see how it's thinking outside the box or being hot-headed to save passengers' lives.

* unsafe to fly and exercising judgement: if you are making the argument that you would never reject above V1, your judgement is not sound and you are not fit for a captaincy. Popped tyre? Sure, go! Engine failure with remaining engine generating adequate thrust? Let's get it! Engine fire? Not your best day, but ok, go!
However, any major fire, anything next to flight control surfaces, wing fire, fire near the tail, cockpit fire, cockpit rapidly filling with smoke - you cannot possibly contemplate going up. You might not even have time to make a VFR turn back to the runway, let alone shoot an actual approach. There might be terrain, you might fly into IMC, you might be taking off at night...just take the overrun. Much better to drive into something at 100-something knots than to fly into something or drop out of the sky.

For a runway like Centaurus' or like the Aussie poster's a little earlier in the thread, where you have a massive seawall at the end and the sea beyond - let's say you have one of those catastrophic fire scenarios. What do you do? You again exercise your judgement and make the best of your circumstances. You rotate, clear the boulders or concrete and come right back down onto the water. Many people have survived overruns (and underruns) into the water, as it is among the mildest accidents you can have, many people have survived ditching, but if you lose control and nosedive into the ocean, the list of survivors becomes much thinner. I can't believe I have to say this, but don't take up a burning aircraft!

Whoever has trained you, nothing in your training precludes common sense. You must always be aware of what your best chances for survival are, and take them when you have to.
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