Boeing 787 Suffers Rare Dual Engine Failure on Landing

Post by dTal » Fri, Feb 01, 2019, 3:03 PM UTC

TremendousJudge wrote: post #146

ChuckMcM wrote: post #132

Earlier quoted context omitted.

Reminds me of the quote, "For every complex problem there is an answer that is clear, simple, and wrong." -- H.L. Mencken One of the things I have experienced in my career is the mind boggling complexity of the software in systems that are capable of killing people. The more people it can kill the more complex the software. As a result when I read articles like the one posted I find it tantalizing to speculate about…

Relevant article: "Reality has a surprising amount of detail" http://johnsalvatier.org/blog/2017/reality-has-a-surprising-...

Post by Wintereise » Sat, Feb 02, 2019, 6:44 AM UTC

ravingraven wrote: post #111

jagger27 wrote: post #73

Earlier quoted context omitted.

> or to only engage reverse thrust once the landing gear has weight on it. Having reverse thrust depend on a sensor that could fail seems like a poor choice. What if the landing gear don't drop? Is there a situation where you would still want reverse thrust without landing gear?

Most things in aircraft automation systems depend on sensors that could fail (those sensors could be redundant etc. but the same can be done with the sensors on landing gears). It is sane design. > What if the landing gear don't drop? I don't think that there is need for reverse thrust in such a scenario. > Is there a situation where you would still want reverse thrust without landing gear? Even if there is, there co…

Post by salawat » Sun, Feb 10, 2019, 5:27 PM UTC

jsjohnst wrote: post #314

salawat wrote: post #273

Earlier quoted context omitted.

The difference isn't that large in the grand scheme of things. The engine mount would have to be able to fail in it's operational envelope in order for the reverser kicking in to be realistic. In fact, the reversed kicking in would decrease the loading on the aircraft by decreasing it's airspeed. This isn't a case of acceleration being able to break the mount from the frame. If it ever could, one wouldn't want it on…

> but it isn't an instant catastrophic failure either. Read the accident report and follow up on Lauda Air Flight 004. Boeing specifically was forced to issue a statement that it was virtually impossible to overcome a catastrophic failure outcome from a thrust reverser deploying at cruising speed.