Originally Posted by
TonyWilliams
I don't have anything remotely technical to research the precise parameters for APR activation, beyond the glossed over pilot level knowledge that we are familiar with. For instance, we know that it makes 500 pounds more thrust. If it failed, could it dump enough fuel for 1,000 pounds thrust? If so, how 'bout 10,000 pounds?
Probably have to ask bombardier on that, but I doubt it would be designed to be able to physically add much more than is required for APR...otherwise you create a potential to destroy the engine during an APR event.
Originally Posted by
TonyWilliams
The thrust lever cables didn't make sense to me, since I assumed that the only place that there was a common failure point was at the actual thrust lever quadrant. It seems that was not a good assumption.
I'm pretty sure the cables follow the same path. A structural failure along that path could bend the cable runs, causing uncommanded power changes. I recall one incident where a rapid depressurization caused the floor to buckle, which affected flight control cables and power lever cables.
I think the thrust levers mechanisms themselves are completely separate (for redundancy). They are just located next to each other.
Originally Posted by
TonyWilliams
I doubt the fuel SOV's failed to shut the engines down. It's more logical that in the seconds before smashing into the building, they didn't get pushed, or if they did, enough momentum had already propelled the plane and its likely overheated brakes couldn't stop it.
They may not have even thought of it at the time...if not, they are kicking themselves now.
Originally Posted by
TonyWilliams
An uncommanded increase in thrust is not a thrust lever cable problem. Stuck at a particular setting, even 100%, sure, but not a change in thrust. If the engines were at a power setting that was low enough for them to even get to the chocks, it doesn't make sense that jammed cables were then able to magically raise that setting, if in fact that's what happened.
Jammed cables would not change the power setting, but a bent cable run could.
Originally Posted by
TonyWilliams
Hopefully we'll get more accurate data as to the actual thrust lever angles / power output.
Yeah, I'm curious.