Is the RAT (Ram Air Turbine) moduled in the NGX?i.e. if I cut off both Engines in Mid-Air would the RAT be deployed and supplythe vital Energy (Electricity) that RAT does in real life ?----- Joel STR

No, as the 737 NG has no RAT.. :-)

the APU is your only option for Hydralic and electrical power in the very unlikely even of duel engine outs.

On ETOPS flights, it's actually required to keep the APU running to serve as a backup for the electrics and that will also run the electric hydraulic pumps. As far as bleed backup, the APU is limited to 17000 for bleed supply. Electrics can be operated up to FL410.

On ETOPS flights, it's actually required to keep the APU running to serve as a backup for the electrics and that will also run the electric hydraulic pumps. As far as bleed backup, the APU is limited to 17000 for bleed supply. Electrics can be operated up to FL410.

Really? That sounds like it costs a lot of extra fuel for just saving these 2 minutes it takes to start the apu up. Is this required for all two engined aircraft like the 777 as well? I honestly have no clue so please enlighten me as I am eager to learn.

Really? That sounds like it costs a lot of extra fuel for just saving these 2 minutes it takes to start the apu up. Is this required for all two engined aircraft like the 777 as well? I honestly have no clue so please enlighten me as I am eager to learn.

I'm sure alot could go wrong in 2 minutes if an aircraft that is airborne lost power.

If i understand, if the airplane has no more fuel to give to the apu, the airplane become like a rock, no possibilities to control the airplane ? I can't understand then Boeing could remove a feature like the rat.

Starting the APU in the air is not very reliable. If something goes wrong at cruise, and that tertiary electrical source is required it is just safer to have it already available instead of starting it on demand and then deal with the likely failed APU start.

The plane won't be like a rock, it will still be contollable. And you have battries that will give you limited instrumentation. The idea is not to run out of fuel.

No, as far as I know it won't go down like a rock because the rudders is still backed up by manual reversion (cables I guess?) but not the rudder Edit: somebody was faster but I got a link for you ;) :http://www.b737.org.uk/flightcontrols.htm

That sounds like it costs a lot of extra fuel for just saving these 2 minutes it takes to start the apu up. Is this required for all two engined aircraft like the 777 as well?

I'm sure alot could go wrong in 2 minutes if an aircraft that is airborne lost power.

Yes. A lot could go wrong in two minutes, but the bigger issue is that the air is too thin to start the APU at altitude. In the end, the time taken to descend and then light the APU would be a lot longer, and in the process, you wasted a lot of altitude that you may not be getting back.

As far as I know the 737 is one of the only aircrafts this size, that is able to fly without any hydraulic systems (The MD80's too, I think).That is the reason why the 737 has only 2 hydraulicsystems and no RAT.For electronic power you've got the batteries.

But i think there is a problem with the RAT to, when you are about to land (let's say a 767) with only RAT powering the airplane, you start flying slower, and the RAT will stop producing power due to the speed, and you lose all hydraulics, and that can be a problem when you are 200-100 ft above the runway, am i right?

Edit: Sorry my comment was for another thread that I thought I was still viewing. Late night

At a 150-200pounds per hour, its not such a big deal to have the apu running. Besides what if you go to start the apu and find out it jst dont work period? Over the ocean and a couple hours away from any airport is not really a time I would like to find that out. And, like some have mentioned, the apu is not guaranteed to start up at high altitudes. JackColwill