Interview with Patrick Ky, hear of EASA a week ago:
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You indicated that you wanted to have a third sensor.That is one of the possible solutions for the angle-of-attack integrity, if you don’t want [the failure of] one sensor having an impact on the integrity of the flight. With two sensors, the weight on one is 50%. If you have three, a failure of one means you still have two that are good. You can still operate under nominal flight conditions. This is one possibility, but there are others we are looking at with Boeing.
A third sensor would be a major change.Yes a very big change, so they won’t do it.
What are the alternatives?There are a lot of opportunities offered by operational procedures. Angle-of-attack is an important piece of information, but it is not vital for the continuation of the flight. Procedures basically allow the crew to identify the failure, to not use the information anymore and continue the flight. The other possibility is not necessarily a third physical sensor but what we call a synthetic sensor. This is based on a setup of other indicators—speed, location and altitude—and with the help of artificial intelligence you can do much more than in the past. It is an interesting way forward and would need one or two years to be developed.