AF447

[infrequentflyer789]

Originally Posted by BOAC

I see 'ssk' reports a not dissimilar IAS issue on a A320 . Are we seeing the same issues on the 737/757/777 ie is it a 'new' wetaher phenomonen or is this somehow ABI common software related?

Short answer: not new. not ABI. At all.

Scenario:

Blocked pitot gives unreliable IAS, feeding into autopilot. Based on bad data (overspeed), autopilot pitches up, drops power, then pilots get handed a nearly-stalled plane. Facing multiple warnings including overspeed and stick shaker, pilots ended up stalled, with high AoA leading to compressor stall too, and high vertical speed ocean impact.

Sound like a familiar speculation from this thread ? Yet it as actually a quick summary of my understanding of this crash:

Crash One: Birgenair Flight 301 | 12 Jun 2009 | ComputerWeekly.com or Birgenair Flight 301 - Wikipedia, the free encyclopedia

Over a decade ago, boeing, not fly by wire, and that is just one example, there are more.

There is just no need to invoke the "evil airbus / fbw removing control from the pilots". Bad IAS (from bad pitot or static data) is a killer, we know that from past experience, and it looks like it still is.