If weight calculation is so crucial for take off, it seems like redundancy of the weight calculation is needed - a different weight calculation from a different company using a different method to verify against the main one.
After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
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Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#102I don't understand why an airplane being heavier than what was estimated by the software would cause the tail to drag. I would assume it would cause the plane to not have sufficient thrust to take off, or to use more runway. But having the tail drag makes it seem like it had too much thrust, which translated to a steeper take off than anticipated... Can somebody explain?
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#103I don't understand why an airplane being heavier than what was estimated by the software would cause the tail to drag. I would assume it would cause the plane to not have sufficient thrust to take off, or to use more runway. But having the tail drag makes it seem like it had too much thrust, which translated to a steeper take off than anticipated... Can somebody explain?
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#104I was under the impression that SOP for most aircraft was to take off at full power, and if you happen to be lightly loaded you just get into the air faster. Was I wrong, or is this a recent change? If so, it seems like a concerning way for airlines to cut costs. Having excess power available at take off means there's a greater margin for error to handle emergencies (engine failure, bird strike, etc.).
Everyone else's (consumer's/engineer's/pilot's) "safety margin" is an executive's "cost to be optimized". Make no mistake. The Exec/finance class will cut into any margin that you aren't willing to make them directly legally culpable for.
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#105>"It delivers a message to the cockpit with crucial weight and balance data, including how many people are on board, the jet’s empty and gross weight and the position of its center of gravity.
>In a cockpit check before takeoff, this data is entered into the flight computer to determine how much thrust the engines will provide and at what speed the jet will be ready to lift off."
Given that overhead bins are regularly maxed out with carry-on luggage now since airlines began charging for checked bags, how are they able to accurately account for the weight and balance? Airlines seem to almost never weigh customers carry-on at check in.
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#106> Peyton added that even though the update to the DynamicSource software had been tested over an extended period, the bug was missed because it only presented when many aircraft at the same time were using the system. That seems horribly wrong to me. I can understand software being slow under load, but being wrong under load sounds like a horrible internal architecture problem.
Maybe a timeout. Some part of a value returned 0 if it didn’t return in time.
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#107737-900s are notoriously tail-heavy. Some airlines require that they use tail stands when parked, and some airlines (like United) have taken measures to redistribute weight forward of the rear landing gear (by moving one of the economy lavatories so that it sits directly behind first class/in front of most economy seating).
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#108Earlier quoted context omitted.
I mean yes, would you rather flights are $10,000 or $100,000 each so the engines are taken apart and rebuilt each time after a flight? Reducing the maintenance interval requirements 'safely' is good for everyone.
Let's reduce the intervals even further so flights are only $10 then, right?
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#109I was under the impression that SOP for most aircraft was to take off at full power, and if you happen to be lightly loaded you just get into the air faster. Was I wrong, or is this a recent change? If so, it seems like a concerning way for airlines to cut costs. Having excess power available at take off means there's a greater margin for error to handle emergencies (engine failure, bird strike, etc.).
Re: After Alaska Airlines planes bump runway, a scramble to ‘pull the plug’
#110Earlier quoted context omitted.
"huge" is not the same as "horrible". One racy boi can take out an airplane.
But calling something an "internal architectural problem" implies things are fundamentally designed wrong, and the code needs a rewrite. My point was the architecture can definitely be fine, but you can still have bugs (even catastrophic ones) because someone left out a `synchronized` keyword somewhere.
For example, one way to use SQL is to escape your parameters and then concat them straight into your SQL string. However, if someone leaves out an ‘escape’ somewhere, you have a major security incident
The other way is to pass parameters separately as data to your SQL driver. It completely negates the problem
If you’ve chosen the first way in your project already, you’ve committed to a major internal architectural problem. In the same vein, maybe if your code requires sprinkling ‘synchronized’ everywhere, you did it wrong
But that said, we don’t know what actually is the problem since it’s just a marketing statement saying that high load was the cause and that doesn’t tell us anything