Air Con -Swine Flu avoidance and 737
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Air Con -Swine Flu avoidance and 737
Have suggested to the company that we ban passengers...no joy.
I am advised by people who know more than me about the 737 recirc system that turning the cockpit recirc fan off will not help stop germs from the cabin.
I thought that the cockpit recirc fan pulled air from the forward cargo compartment...and this sinks from the cabin?
Can someone who understands the system shed any light?
I am advised by people who know more than me about the 737 recirc system that turning the cockpit recirc fan off will not help stop germs from the cabin.
I thought that the cockpit recirc fan pulled air from the forward cargo compartment...and this sinks from the cabin?
Can someone who understands the system shed any light?
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Yup, they're right.
Air re-circs from cabin via mixer chamber up again to top of cabin.
Germs enjoy a nice round trip. Several times.
Switching off re-circ fans won't make any difference.
Recommend SCUBA gear. And a good wash after.
Air re-circs from cabin via mixer chamber up again to top of cabin.
Germs enjoy a nice round trip. Several times.
Switching off re-circ fans won't make any difference.
Recommend SCUBA gear. And a good wash after.
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Most a/c now use HEPA filters in the recirulating system. These are about 99.99% efficient in the removal of particulate contamination including viral types. These types of filter are also used in laboratories dealing with radioactiveand pharmacuetical products.
Therefore the recirculated air is almost free of particular and viral contaminants. Travelling on a plane is no more risky in this effect than being on a train or bus. If you catch flu, it will be the virusses first trip and is unlikely to be as a result of the air being recirculated. The engineer changing the filter however, has a far greater chance of catching something.
HEPA - Wikipedia, the free encyclopedia may explain more.
Therefore the recirculated air is almost free of particular and viral contaminants. Travelling on a plane is no more risky in this effect than being on a train or bus. If you catch flu, it will be the virusses first trip and is unlikely to be as a result of the air being recirculated. The engineer changing the filter however, has a far greater chance of catching something.
HEPA - Wikipedia, the free encyclopedia may explain more.
Might also suggest that you stop watching the news until the next financial crisis, environmental disaster or other newsworthy event which will divert the media's attention onto some "real" news.
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I always thought there was something about the flight deck getting 100% fresh air or at least more than the cabin, supplied from the left pack rather than the mix manifold?
Although I've noticed on the ground with the packs off, there is still some air coming through the gasper vents in the flight deck, which I can only assume is from the recirc fans. Where exactly are these fans located and where does the air come from/to? I've noticed they are quite noisey in the cockpit.
Although I've noticed on the ground with the packs off, there is still some air coming through the gasper vents in the flight deck, which I can only assume is from the recirc fans. Where exactly are these fans located and where does the air come from/to? I've noticed they are quite noisey in the cockpit.
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My dear pilots !!
RYFM before starting a post 
The control cabin, so called cockpit , has a 100% fresh air supply.
Any questions ?? Don't ask me if U have to wear a breathing gear when U go for a leak
rgds
The control cabin, so called cockpit , has a 100% fresh air supply.
The left air conditioning pack supplies the conditioned air for the flight compartment.
The air flows through ducts that go forward along the left side of the airplane.
The flight compartment distribution uses different ducts than the passenger compartmentv distribution.
The flight compartment receives conditioned air from the right pack if the left pack is not operational.
The flight compartment distribution lets the flight crew select a different air temperature than the other areas of the airplane. The air quality is better because it comes from the left pack and is not mixed with recirculated air.
The air flows through ducts that go forward along the left side of the airplane.
The flight compartment distribution uses different ducts than the passenger compartmentv distribution.
The flight compartment receives conditioned air from the right pack if the left pack is not operational.
The flight compartment distribution lets the flight crew select a different air temperature than the other areas of the airplane. The air quality is better because it comes from the left pack and is not mixed with recirculated air.
Any questions ?? Don't ask me if U have to wear a breathing gear when U go for a leak
rgds
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h3DXB - I admit I am lazy and don't read the tech manuals as much as I should. However you don't get quality refs like the above links to HEPA and The Lancet by reading, what is after all, a very basic systems description.
Is this the answer you give to your F/Os when they ask you a question? Maybe you do not remember the time when you did not know everything there is to know?
Is this the answer you give to your F/Os when they ask you a question? Maybe you do not remember the time when you did not know everything there is to know?
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300-600
I agree there are no stupid questions, only stupid answers.........
but a simple look in the handbook, system description ATA chapter 21, Air distribution to control cabin, and there wouldn't be such a question.
If U like I can send U a screenshoot.
And BTW, this is a Tech Forum I'm the guy how knows the plane and explains it to you guy's behind the steering
Never became a pilot, toooooooooo many switches and gauges and indications there
I agree there are no stupid questions, only stupid answers.........
but a simple look in the handbook, system description ATA chapter 21, Air distribution to control cabin, and there wouldn't be such a question.
If U like I can send U a screenshoot.
And BTW, this is a Tech Forum I'm the guy how knows the plane and explains it to you guy's behind the steering
Never became a pilot, toooooooooo many switches and gauges and indications there
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RMC
Actually I took the infos from the NG Training documentation.
During normal operation, two electrical recirculation fans draw air from the passenger compartment and the equipment cooling system through filters. The recirculation air is delivered to the mix manifold through check valves. The recirculation fans and check valves are identical and interchangeable. The recirculation rate
is approximately 47 m3 per minute. No recirculated air goes into the flight
compartment.
The air in the airplane is changed every three minutes.
Like I also remember, It is mandantory by law to have an independent airflow to the cockpit.
rgds
Actually I took the infos from the NG Training documentation.
During normal operation, two electrical recirculation fans draw air from the passenger compartment and the equipment cooling system through filters. The recirculation air is delivered to the mix manifold through check valves. The recirculation fans and check valves are identical and interchangeable. The recirculation rate
is approximately 47 m3 per minute. No recirculated air goes into the flight
compartment.
The air in the airplane is changed every three minutes.
Like I also remember, It is mandantory by law to have an independent airflow to the cockpit.
rgds
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Best effort is not to drive to the airport. You'll probably get into a car accident before you catch the flu. Oh, and is that a ciagarette you're smoking?
Lets get real..CNN and the rest of the news agencies have made some good $$$ selling the hype.
Lets get real..CNN and the rest of the news agencies have made some good $$$ selling the hype.
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I'm not worried about it _now_ but it does have the potential to get nasty...
The Associated Press: Top flu expert warns of a swine flu-bird flu mix
The Associated Press: Top flu expert warns of a swine flu-bird flu mix
Sure I just saw a flying pig on TCAS.
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Sorry for repeating myself a bit, I get it that the flight deck is supplied directly off the left pack so during normal flight there shouldn't be any recirculated air, however, when I'm getting an amazing piece of culinary delight made in the forward galley oven, it can usually be smelt very clearly in the flight deck - is this just natural air leakage coming through the bulkhead etc? I also thought the only exit path for the air would be out via the door, so the flightdeck is under positive pressure?
Also, when on the ground with APU/Packs off, there's a small amount of air coming through the sidewall vents and a fair bit from the gasper vents below the displays - I assume this is from the recirc fans pressurising the mix manifold, which then comes back down to the flightdeck via the connection to the left pack?
Also, when on the ground with APU/Packs off, there's a small amount of air coming through the sidewall vents and a fair bit from the gasper vents below the displays - I assume this is from the recirc fans pressurising the mix manifold, which then comes back down to the flightdeck via the connection to the left pack?
