perhaps someone could help me understand how routing works over high ground in commercial aviation.

 

 

 

 

from what I can tell from various dvds an airliner cannot safely fly over terrain higher than 10000 ft incase of a sudden cabin decompression unless it is able to reach and area with max terrain height of 10000 ft within ten mins of the decompression. this must make routing pretty restrictive as ten mins is not a long time and at approx. 495 kts means a dist of approx. 80 nm. therefore you have to be within 80 nm of terrain of 10000 or less at all times during the flight?

have I understood this correctly? .so based on this I wonder why there are numerous airways around the world that defy this logic and rout over terrain of plus 10000 to 22000 in some cases such as southern china and are also way beyond 80 nm of safe terrain height of 10000

 

 

 

 

can anyone help explain how this rule is meant to work in reality

 

 

 

 

 

 

tks

 

 

kav

Look up the term "Drift Down Procedure".  Essentially, along every leg of a trip, they have to have routes planned for an engine out condition.  But your own Google searching will result in better explanations that I can give in this short reply.

It depends on the oxygen systems on board for pax and crew.

 

Normally the chemical oxygen generators are more limiting than the oxygen bottles that provide the cockpit crew with oxygen.

 

In short:

You can fly above 10.000ft (cabin altitude!) as long as those oxygen generators provide oxygen.

After those are empty you can fly an additional 30 minutes between 10.000-14000ft (cabin altitude!) without any oxygen.

This might be different from operator to operator or FAA to JAA regulations.

 

The 737 I am familiar with had generators that lasted 12 minutes.

The ones on the 777 I am familiar with, last for 22 minutes.

With those 22 + 30 minutes you can cover quite a bit of high terrain.

 

Hope this helps

Ok yes thanks

 

 

 

 

 

 

kav

Operators can get approval to use 14000 ft as the decompression altitude if they meet special oxygen requirements.

I saw "escape routing," thought you meant ATC escape routing, and got excited that I would get to talk about more ATC stuff more people don't know about...womp.

 

Good info here all the same.

I saw "escape routing," thought you meant ATC escape routing, and got excited that I would get to talk about more ATC stuff more people don't know about...womp.

 

Good info here all the same.

ok i'll bite :-)

 

What is an ATC escape routing Kyle?

 

Ps Happy Halloween from NYC!

 

 

What is an ATC escape routing Kyle?

 

haha - they're route offloads for times when seasonal volume overwhelms, or weather cuts down rates.  Operators file out through different fixes/routes to enable them to leave the airport and avoid delay.

 

I'll leave it at that to keep from a total thread hijack.

Captain Gerd Puppel (Lufthansa A340 skipper) has a varied and comprehensive set of worldwide charts (www.planningchart.de) which when laminated at A4 size fit into your flight folder nicely and allow quick reference along with being able to show the CC where they are (approx) when you are asked the usual "Where are we now"?

Usual caveats apply about not for operational planning and reliability of freqs, updates etc, but overall a nice thing to have (in colour) when you want a quick look at where you are as opposed to unfurling the big paper charts

 

 

See 2:00 into this video,http://www.youtube.com/watch?v=ID7F5GX5QTk

+1

 

His NA ETOPS chart is very useful, has all the relevant airports listed with rwy / minima and so on. Impressively compact, prints and reads well in A4 format.

haha - they're route offloads for times when seasonal volume overwhelms, or weather cuts down rates.  Operators file out through different fixes/routes to enable them to leave the airport and avoid delay.

 

I'll leave it at that to keep from a total thread hijack.

Ah ok. Thx!