Aviation professional here
My first thought on reading this: nah, the headline is wrong.
Then I go and read the airworthiness directive, helpfully linked in the article: oops! the headline is right.
The rest of the article is nicely done, clearly the author has put some effort into getting things right, which is a refreshing change from most aviation-related articles in the non-specialised press.
Just one minor nitpick, as a former commercial pilot (technically still qualified and medically fit but no longer active):
> Missed approaches are used when pilots aren't confident that they're going to land safely.
I realise this is an intentional simplification but it is not a matter of confidence. More often than not you're completely confident of being able to land but if the conditions dictate otherwise you are going up again regardless. For instance if the weather is below minima, the approach is not stable, or quite simply you did not get landing clearance on time because someone was hogging the radio.
From a cognitive point of view the missed approach is your plan A, landing is plan B.
Also, the article seems to confuse temperature compensation with temperature correction. Those are two different things and it's the latter that seems to be concerned here. It applies in a specific type of instrument approaches (Baro-VNAV) and the consequence of the AD is to make those approaches unusable by aircraft with affected FMS on days colder than the minimum promulgated temperature. The reason why it ends up affecting the turn direction (obviously, other than the there being a mistake in the code) is because the length of the final approach segment (the bit where you aim for the runway, ending at the missed approach point) is indirectly dependent on temperature on those types of approach.
Someone above commented that this is not a serious mistake because you should be able to catch it. That is not so. In my qualified opinion (and the regulators agree) this is a major problem for at least two reasons: when you are in the soup it may not be immediately obvious which way the aircraft is turning (and there is such a thing as confirmation bias) and even if/when you realise that it's gone for a wander, you are still faced with the dreaded "what on Earth is it doing?" question, which is not a good position to be in at 150+ knots, low energy, close to the ground and with a few tons of aircraft and cargo behind you. In a non-radar environment and with the "wrong" sort of environment and circumstances even if you perform at your best you may not be able to recover the situation.
Quite tired so apologies if not as clear as I would have liked.
Biting the hand that feeds IT
