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whopis01

(3,921 posts)

83. I'm not entirely sure I understand what you are saying, but I will try to explain my point

Sat Mar 15, 2014, 10:53 AM

Mar 2014

The FAA places a limit on the cabin altitude pressure of 8000ft. The pressure at 8000ft is roughly 11.2psi. So that means the aircraft has to maintain a pressure differential great enough to keep the cabin pressure at least at 11.2psi.

The Boeing 777 pressurization system can produce a maximum differential of 8.6psi. So that means if the outside air pressure is less that 2.6psi, it would be unable to maintain an inside pressure of 11.2psi.

The air pressure at 43,100 feet is 2.6psi - therefore if the aircraft were to fly higher than that, it would not be able to meet the FAA pressurization requirements.

FAA pressurization requirements:
http://www.ecfr.gov/cgi-bin/text-idx?SID=6950de6f84f12fb18c001de16a9b918a&node=14:1.0.1.3.11.4.180.71&rgn=div8

777 performance guarantees (see section 6.5)
http://www.sec.gov/Archives/edgar/data/6201/000095012311037302/d81257exv10w2wg.htm

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Malaysian Officials have concluded missing flight #MH370 was hijacked and steered off course [View all] Renew Deal Mar 2014 OP

Then they need to start searching airports and straight, level highways Warpy Mar 2014 #1

Search where? Renew Deal Mar 2014 #2

If the plane was hijacked I suspect many of the passengers are still alive Bjorn Against Mar 2014 #4

It takes a hell of a long runway to land one of those Warpy Mar 2014 #6

I don't think it is in Pakistan as I agree that would be hard to get to Bjorn Against Mar 2014 #11

With Autobrake set to max... awoke_in_2003 Mar 2014 #15

1,780m on the 200 variant. AtheistCrusader Mar 2014 #30

Exactly... awoke_in_2003 Mar 2014 #34

Right, pangaia Mar 2014 #67

With the amount of fuel as was likely to be left, pangaia Mar 2014 #64

can you land a big plane like that in the desert? Voice for Peace Mar 2014 #110

Unlikely, deserts aren't generally very flat Warpy Mar 2014 #117

And if it were part of a planned operation how hard would it be? kristopher Mar 2014 #124

Sadly, no passenger would survive the time the plane was at 45,000 feet. PSPS Mar 2014 #22

Why not? awoke_in_2003 Mar 2014 #35

Because it's service ceiling is 43,100 ft whopis01 Mar 2014 #43

How do you know that the ceiling is due to the limit of the ability to maintain pressurization? muriel_volestrangler Mar 2014 #49

Because that is the pressurization limit whopis01 Mar 2014 #52

Who says it's the pressurization limit? muriel_volestrangler Mar 2014 #69

Just saw your post right after I posted mine just below. pangaia Mar 2014 #71

This (from someone who claims to know the plane): muriel_volestrangler Mar 2014 #74

Boeing (combined with regulations) says it is the pressurization limit whopis01 Mar 2014 #81

Thanks - that does make sense, looking at different versions muriel_volestrangler Mar 2014 #92

The service ceiling is based on the aircrafts ability pangaia Mar 2014 #70

FAA does not define it the way you do. MyNameGoesHere Mar 2014 #79

I'm not entirely sure I understand what you are saying, but I will try to explain my point whopis01 Mar 2014 #83

Cabin pressure alone is not the ONLY limiting factor MyNameGoesHere Mar 2014 #119

Correct. The ceiling will be limited by the lowest altitude factor. whopis01 Mar 2014 #126

This AM CNN had a segment with a 777 flight simulator at 45K kristopher Mar 2014 #128

Came across the video - here's the link kristopher Mar 2014 #152

Thanks... awoke_in_2003 Mar 2014 #96

I always thought passenger drop-down oxygen masks were deployed truth2power Mar 2014 #78

They are, but work for only a few minutes. PSPS Mar 2014 #85

thanks. Clears that up. n/t truth2power Mar 2014 #88

Wow, so the pilot could have had access to a potential murder switch? JimDandy Mar 2014 #113

I am with you "previously unbelievale" Iwasthere Mar 2014 #138

What's scary is it's NOT a conspiracy, if all it takes is one person to hijack a plane! JimDandy Mar 2014 #143

Aren't there oxygen masks on planes? bitchkitty Mar 2014 #103

Yes, but they work for only a few minutes. PSPS Mar 2014 #105

That's bad news... bitchkitty Mar 2014 #107

I doubt the plane could have gotten to 45,000 feet TorchTheWitch Mar 2014 #144

It did climb to 45,000. That came out days ago. PSPS Mar 2014 #146

I hope you are right davidpdx Mar 2014 #56

Leftover Vietnam era landing strips? grahamhgreen Mar 2014 #57

So I guess those of us who thought the plane was stolen were not "conspiracy theorists" after all Bjorn Against Mar 2014 #3

.... DeSwiss Mar 2014 #10

Can't disagree with that Bjorn Against Mar 2014 #13

Great quote! red dog 1 Mar 2014 #19

That's a keeper. And here's another one about conspiracies... truth2power Mar 2014 #77

Michael Parenti is brilliant, pure & simple. red dog 1 Mar 2014 #127

Thanks for pointing out the JFK material on the Parenti site. I'll take a look... truth2power Mar 2014 #145

IMO, the best book written about the JFK Murder is by Peter Dale Scott... red dog 1 Mar 2014 #148

Exactly. DeSwiss Mar 2014 #135

I don't recall any objections about conspiracies. The objection was wild unfounded specalution BlueStreak Mar 2014 #59

As the OP confirms, it wasn't "wild unfounded speculation" kristopher Mar 2014 #65

Well then I guess anyone who suggested anything was talking out their asses Bjorn Against Mar 2014 #76

Actually, the speculation that it had CRASHED was based on nothing. B2G Mar 2014 #82

It was based on official Malaysian statements that the plane doubled back over the Malacca strait BlueStreak Mar 2014 #130

When it became clear that the plane drastically altered course, B2G Mar 2014 #141

Oh, now it's that now. "Unfounded speculation"... truth2power Mar 2014 #95

This right here, BlueStreak! You have a response? nt ChisolmTrailDem Mar 2014 #122

Didn't the release of the alleged fact that cell phones savannah43 Mar 2014 #139

So let me get this straight BlueStreak Mar 2014 #140

The ring you hear when calling a cell or landline phone IDemo Mar 2014 #142

This has to be A Sick Rollercoaster for the Families lib87 Mar 2014 #5

I guess for tonight anyway... SoapBox Mar 2014 #7

Look at this Renew Deal Mar 2014 #8

Another article I read said that is what you hear when the system is looking for your phone uppityperson Mar 2014 #21

Well the other theory would be if the plane were hijacked and the passengers were alive davidpdx Mar 2014 #54

The poor families. Too many "ifs" still, as my spouse said "movie makings". nt uppityperson Mar 2014 #129

If I turn my cell off and call it from another phone whopis01 Mar 2014 #44

Picture at the link is heartbreaking: freshwest Mar 2014 #132

There are no cell towers on the ocean. longship Mar 2014 #14

I don't know that you could count on a cell phone call if the plane landed Bjorn Against Mar 2014 #16

Were the pilots Islamic terrorists? nt Sarah Ibarruri Mar 2014 #9

Undecided. obxhead Mar 2014 #32

+100 Myrina Mar 2014 #104

You think all this has been been done by TPTB to create a "situation?" nt Sarah Ibarruri Mar 2014 #147

I did not say that obxhead Mar 2014 #149

''Conclusive'' :-| n/t DeSwiss Mar 2014 #12

Kick Cha Mar 2014 #17

The same government officials who, perhaps, called in a shaman? jtuck004 Mar 2014 #18

K&R.....Thanks for posting red dog 1 Mar 2014 #20

Consider this... icarusxat Mar 2014 #118

"Our CIA and NSA have gone rogue" EX500rider Mar 2014 #123

Consider this jmowreader Mar 2014 #136

Edit: Conference not quite started yet. greyl Mar 2014 #23

I think there will be a statement with no questions and then Renew Deal Mar 2014 #24

Did you catch an updated time for the statement? nt greyl Mar 2014 #26

No Renew Deal Mar 2014 #28

Lol, I thought he kept saying 5:30 was a different issue. greyl Mar 2014 #29

They were awaiting the arrival of the Chinese Ambassador to Malaysia... countryjake Mar 2014 #58

Biggest DUH ever. maced666 Mar 2014 #25

Pirates. ErikJ Mar 2014 #27

Every plane 'should' have to send a signal with its location every five minutes to a satelite... Tx4obama Mar 2014 #31

The airlines should be sewing beacons into the wing if necessary davidpdx Mar 2014 #55

Seriously, the pilot turning off the transponders in a commercial aircraft should AtheistCrusader Mar 2014 #89

I agree davidpdx Mar 2014 #121

There will be a call for something like this after the MH370 incident LongTomH Mar 2014 #137