Might be the increased risks in lithium battery technology of self-ignition and thermal runaway. Once an aircraft design has incorporated nickel-cadmium NiCd battery technology, it is a major design change to convert to lithium, including going back to the hazard analysis and ensuring that additional risks have been mitigated. Lithium battery technology should only be employed in an aircraft design when its weight-to-energy advantage is essential. And the mechanical packaging, the more complex charging circuitry, and temperature monitoring must all be carefully designed and validated for safety.

(Written on 2020年 11月 06日)(Permalink)

I went to the Harvard T.H. Chan School of Public Health website. Found a note about this on-going research, but no report. Has anyone else found the report? I'm VERY suspicious of this "1%" statistic.

(Written on 2020年 10月 02日)(Permalink)

Or, "it's OK to have Anthony Hopkins over for dinner."

(Written on 2020年 09月 25日)(Permalink)

Agreed that "celebrity status" is not a measure of competence. And don't confuse an actor with the characters that he/she has played. They are usually completely unrelated.

(Written on 2020年 09月 25日)(Permalink)

For 8 years we lived in Alameda about a mile north of the Oakland Airport runway. We were treated daily to an endless stream of all types of aircraft climbing out. Plus, there were bonus yearly sightings during Fleet Week of the Blue Angels forming up right off our back yard after dual take-offs, and the occasional Concorde round-the-world charter flight straightening out the droop nose as it howled into the air. Most of my neighbors were noise whiners, but we aviation buffs were in heaven.

(Written on 2020年 09月 11日)(Permalink)

My memories are fading here, but the hotter landings might be related to the issue of a steep nose-up attitude causing the wings to block air to the tail and causing a stall of the high-mounted vertical stabilizer. This caused at least one landing accident early in the 727's service. The fix was to increase landing speed. Does anyone remember this? Can't find a reference to it ...

(Written on 2020年 08月 14日)(Permalink)

Good point, microwalda. This is especially true in safety-critical systems. When a system meets its requirements and is well seasoned, leave it alone.

(Written on 2020年 08月 14日)(Permalink)

Great example of Mr. Huls' point above. My Dad flew Mustangs with Bob in the fifties. Bob was a true pilot's pilot. But even airmen of Bob Hoover's calibre and experience can make a mistake.

(Written on 2020年 07月 24日)(Permalink)

w2bsa, Stephen, and Thomas: I call. I have a similar 40 year background in software engineering, with the last 25 years spent in safety-significant software systems for medical devices. All of your general comments on software design are correct -- software of any complexity will have faults and defects. What alarms me (pun intended) is that, in the FINAL verification and validation phase of this software development, Boeing is still finding defects in the avionics software that have the HIGHEST risk severity possible: loss of the aircraft. In my experience, finding such new show-stopping high-risk defects at this late stage of development is a huge red flag that indicates 1) the software architecture is flawed in its ability to detect, contain, and mitigate high-risk failures ("exception handling"), and 2) the software development PROCESS employed was itself flawed in its ability to find and mitigate to safe levels these high-risk defects("defect containment") during review, ins

(Written on 2020年 04月 11日)(Permalink)

Yes, the fact that he claims he didn't want to hurt anyone is a factor, but it is heavily outweighed by the potential severe harm his actions could have caused. And revenge would be a factor if some of the pilots and frequent fliers in this forum (who might take his actions as a personal threat) got ahold of this mechanic and beat him to death. So yes, let's keep him safely locked up and subject him to the full weight of the criminal justice system, which is quite capable of differentiating vindictive revenge from the protection of society (you and me) from the potential harm of this man's actions.

(Written on 2019年 09月 13日)(Permalink)