A380 whistlebower

GravityHater

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Wowza I had no idea!!

"Until the 1940s, commercial airplanes were not pressurized and could fly only at about 10,000 feet. Flying above the clouds, around 30,000 feet, would make flights smoother, but at that altitude a lack of oxygen and temperatures of 140 degrees below freezing would kill passengers within minutes."
 
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viper548 said:
It looks like the -140 degrees came from the Times writer.

whats wrong with that? My last flight (in the summer) was planned for exactly -60c / -140 F at our top of descent (FL380).
 
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Interesting. My Texas Instruments TI-86 does the conversion wrong. If you have a TI calculator try doing the conversion from -60 C and it might give you -140 (at least mine does). Maybe the NY times writer did the conversion on a calculator with a conversion feature that was messed up (like I did). Hopefully Texas Instruments was not involved in the development of the A380 =). But, I do find it ironic he was writing an article about faulty software in a microchip and using a calculator with such a fault itself.
 
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EagleRJ

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Flyinisforbirds said:
Interesting. My Texas Instruments TI-86 does the conversion wrong. If you have a TI calculator try doing the conversion from -60 C and it might give you -140 (at least mine does). Maybe the NY times writer did the conversion on a calculator with a conversion feature that was messed up (like I did). Hopefully Texas Instruments was not involved in the development of the A380 =). But, I do find it ironic he was writing an article about faulty software in a microchip and using a calculator with such a fault itself.

+60C = +140F

However, -60C = -76F
 

AdlerDriver

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dispatcher121 said:
I feel for his family. They are suffereing. It's too bad the laws in Austria don't protect him.
dispatcher121 said:

OMG do you realize the ramifications of his allegations?
If he is correct, he will be saving MANY lives.


I think they are blowing his concerns a little out of proportion. Even if all the outflow valves failed open at the same time, it’s still going to take minutes for the aircraft to fully depressurize, not seconds. Outflow valves are not capable of generating an explosive depressurization in seconds. Most aircraft I’ve flown have max cabin rates in the ballpark of ~2000 FPM with the outflow valves fully open. Typical cabin altitudes of 4000-6000 feet at cruise above FL300 means it’s going to take a while to dump the cabin. Plenty of time to get a mask on and start a descent.

Not to say a known problem with poor system redundancy isn’t something to investigate and fix. I just don’t think it’s the life or death issue the press is making it out to be.
 

GravityHater

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I have always wondered what the approximate cross sectional area of a fully opened outflow valve is, say on a typical airliner. Are we talking several square inches? Just wanted to get a feel for how much air or air flow would be experienced.
 

Draginass

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I question why this guy didn't get his family and himself OUT of the political morass in the EU before going public with his opinion.
 

AdlerDriver

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GravityHater said:
I have always wondered what the approximate cross sectional area of a fully opened outflow valve is, say on a typical airliner. Are we talking several square inches? Just wanted to get a feel for how much air or air flow would be experienced.

I never stopped to measure. Obviously size is dependent on the aircraft. Most seem to be rectangular and maybe 12 to 14" x 12 to 18". So, 1 to 1.5 sq. ft - give or take a little.

UAL was training us with tasers right after 9-11. In the class, I remember them discouraging pilots from using depressurization as a defensive tactic during a takeover attempt. It was going to take about 10 minutes depending on aircraft type. The masks were going to drop anyway, so it's not like the bad guys were going to conveniently pass out. You have to descend to land, so even if they did pass out, they're probably going to wake up before you land. I still had a Capt (scab - so proven bad judgment anyway) swear it would work and it was going to happen on his aircraft if we ran into trouble. Hell, most places in the USA, I can be on final to a piece of concrete in 10 minutes.
 

millhouse21

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I'd be more concerned about the lack of a backup controller. I mean, we all know that a software fault could NEVER happen. Right?
 

BLing

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Flyinisforbirds said:
Interesting. My Texas Instruments TI-86 does the conversion wrong. If you have a TI calculator try doing the conversion from -60 C and it might give you -140 (at least mine does). Maybe the NY times writer did the conversion on a calculator with a conversion feature that was messed up (like I did). Hopefully Texas Instruments was not involved in the development of the A380 =). But, I do find it ironic he was writing an article about faulty software in a microchip and using a calculator with such a fault itself.

Mine does the conversion wrong too. Found that out the hard way in a college physics class I took about 2 years ago.
 

A Squared

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EagleRJ said:
+60C = +140F

However, -60C = -76F
Right, which is 108 degrees "below freezing", but that still isn't 140 degrees below freezing

140 degrees below freezing would be -108F or -78 C
 
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