quote van flightinfo:
"The media wasn't speculating. The article was quoting the NTSB spokesman, and their job involves a process of educated speculation to form avenues of investigation. All the NTSB guy said regarding the a/c being at FL410 was that "it was the most interesting thing". I'm sure that it's always noticed and they become interested (and it therefore becomes one of those avenues of investigation) if any accident a/c is operating at the limit of it's certified perf envelope just before things go wrong.
This would be especially true with regards to it's max alt certification with the seriously-degraded performance, and in the case of jets, the hostile environment to crew and systems you find there. They wouldn't be doing their jobs very well if they weren't keeping that in mind, even if it turns out not to be a factor.
He'd say that, because they are fully aware that 99% of CRJ/CFE-34 hours are flown at Flight Levels in the 20's and 30's. The fleet-wide, historical experience up at FL410 is very, very limited. The "personal testaments" we see here that the aircraft and engines "Do just fine" and is "Easily hand-flown" at FL410 notwithstanding, it's axiomatic that aircraft perform differently on different days depending on conditions, especially up there where increases in temps relative to ISA can degrade perf in a non-linear fashion, where turb and shear becomes a major concern, and where ultra-low SATs can do bad things to systems that don't manifest themselves at more comfortable ones. We don't know what the flight conditions were that night at FL410, or during the climb.
Frankly, it's unsupported speculation to declare the altitude issue isn't important just because it went there for certification or a few have done it once or twice, and somewhat irresponsible to imply that CRJs/CFE-34s routinely and happily do it. I only have a couple thousand hours in CRJs, far less than some of you here, granted, but in my experience (including many lightweight, mx-ferry flights) for all it's good points, the thing's a dog above FL350 anytime, and at any FL when it's ISA+8 or higher. There's just no getting around the fact that it wasn't designed as a high-altitude performer, so it's rarely operated at it's certified limit.
All that being said, you can be sure they are going through all the systems, the mx procedures performed not just prior to the flight (most likely THE biggest thing they are "interested in"), but anything engine/fuel system related as far back as they can find. No doubt they descended on the last fuel farm/truck they used looking for contaminants. And like it or not, they're looking at the crew and their performance in a detached way that's hard for us to do here, since they were our brothers.
We can sit here and run through every possiblilty and yet they might find something completely out of the blue, like those guys were unlucky enough to have ingested the world's highest flying flock of geese unseen in the dark, or they took a one-in-a-billion meteor strike in the tail. Or someone that's happened too many times before with a/c just out of mx; a wrench forgotton in the wrong place, cannon plugs not secured, something not safety wired. We just don't know yet.
If anything, this terrible loss has already provoked discussions about things (which may have not played a role in this accident's cause) we might have become complacent on, or never known, because they ARE the speculative "what-if's". Such discussions are usually beneficial, they're normal, and they DON'T do a disservice to the crew and process, or feed a Rumor Mill, if they remain thoughtful. Case in point; someone has brought up the limited training crews at a lot regional airlines receive in high-altitude flight, which even if it wasn't a factor here, focuses our thoughts about what our own training and limitations might be. Same thing when someone else pointed to his thoughts of taking an aircraft just out of mx.
It's all food for thought, and up until the point someone without the facts begins pretending to know what happened or assigning blame in this accident whether that be to crew, mx, handlers, or even mngmt, such focus and the exchange of even tangental info can serve a good purpose, or at least a reminder in the face of a tragic event."
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http://forums.flightinfo.com/showthread.php?t=41254