Archives For epistemic risk

Well it was either Crowley or Kylie Minogue given the title of the post, so think yourselves lucky (Image source: Warner Brothers TV)

Sometimes it’s just a choice between bad and worse

If we accept that different types of uncertainty create different types of risk then it follows that we may in fact be able to trade one type of risk for another, and in certain circumstances this may be a preferable option.

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The pentagon is functioning (Image Source: USN)

….And there are still unknown, unknowns

A while ago I posted a short piece on the difference between aleatory, epistemic and ontological uncertainty, using Don Rumsfeld’s famous news conference comments as a good introduction to the subject.

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Air France Tail plane (Image Source: Agencia Brasil CCLA 2.5)

Requirements completeness and the AF447 stall warning

Reading through the BEA’s precis of the data contained on Air France’s AF447 Flight Data Recorder you find that during the final minutes of AF447 the aircrafts stall warning ceased, even though the aircraft was still stalled, thereby removed a significant cue to the aircrew that they had flown the aircraft into a deep stall.

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The BEA has released a precis of the data contained on AF447’s Flight Data Recorder and we can know look into the cockpit of AF447 in those last terrifying minutes.

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Why taking risk is an inherent part of the human condition

On the 6th of May 1968 Neil Armstrong stepped aboard the Lunar Lander Test Vehicle (LLTV) for a routine training mission. During the flight the vehicle went out of control and crashed with Armstrong ejecting to safety seconds before impact. Continue Reading…

Over the last couple of months I’ve posted on various incidents involving the Airbus A330 aircraft from the perspective of system safety. As these posts are scattered through my blog I thought I’d pull them together, the earliest post is at the bottom.

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So far as we know flight AF 447 fell out of the sky with its systems performing as their designers had specified, if not how they expected, right up-to the point that it impacted the surface of the ocean.

So how is it possible that incorrect air data could simultaneously cause upsets in aircraft functions as disparate as engine thrust management, flight law protection and traffic avoidance?

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