I read the manual and have a few questions about operations.The manual NP procedures Section 21 starts with the cockpit powered up - so I have this question:1. Can the APU be started without any fuel pumps on - or do I have to have atleast 1 pump on.2. Section NP21 talks about the pushback and the nose gaer locking pin. I need to verify that the pin in installed. And if so, keep the A hydraulic pump off.Dumb question, what the heck is the pin - and how do I verify if it is insatlled. I am guessing it locks the tow bar to the nose gear and by keepin the A hydraulic pump off, the nose wheel can be turned by the "mule" push back dude? Correct?3. What is the puropse on having the engine switches set to CONT for take off and landing only? Why not during the entire flight?4. If a pilot is rated on the 747NGX 600, is he/she rated on the 700, 800 and 900 also? 5. On the 767, I was taught to leave the APU bleed switch on after the APU is shuit off, it seems like on the 737 the APU bleed switch is turned off when the APU is shut down. Correct?ThanksPaul

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1. Can the APU be started without any fuel pumps on - or do I have to have atleast 1 pump on.Assuming you're running on battery, there is actually no way to run any fuel pump. And yes, the APU runs without any fuel pump but you are advised to have one pump running to help provide positive pressure after APU start. I see the #1 tank AFT pump operating most of the time.2. Section NP21 talks about the pushback and the nose gaer locking pin. I need to verify that the pin in installed. And if so, keep the A hydraulic pump off.Dumb question, what the heck is the pin - and how do I verify if it is insatlled. I am guessing it locks the tow bar to the nose gear and by keepin the A hydraulic pump off, the nose wheel can be turned by the "mule" push back dude? Correct?The pin will remove hydraulic pressure so they won't do damage to the NLG steering. That way you could actually have the A pumps running, but if you want to be super safe (or if it's your SOP) then they will remain off until after pushback or so.3. What is the puropse on having the engine switches set to CONT for take off and landing only? Why not during the entire flight?I would assume the igniters have some amount of wear. During take off and landing and whenever engine A/I is on the igniters should be operating to prevent engine flameout.4. If a pilot is rated on the 747NGX 600, is he/she rated on the 700, 800 and 900 also?Not exactly sure but I seem to remember it's some sort of a combined rating, e. g. 700/800 or the like. Like the 'bus drivers have 318/319/320/321 in their license even if they only operate a single type of the four.5. On the 767, I was taught to leave the APU bleed switch on after the APU is shuit off, it seems like on the 737 the APU bleed switch is turned off when the APU is shut down. Correct?According to NP, for example after engine start, you are correct, and APU bleed is the last item to be switched off before shutting down the APU.

Since badderjet already answered most of your questions, I'll add something to his reply instead of finishing mine (was about halfway through :D)Purely on a type-rating basis, the entire 737 series is one single type rating. There will be some training involved to switch between Classics and NG's for example. Or the ultra short 736 to the ultra long 739, but there is just one type rating.Also, in real life, there is no NGX, just the NG ;-)

Thanks guys for the replies. I am trying to absorb all this before my session in the full motion simulator.

1. Yes it can.3. Because that's how the jet was certified.4. There is only one 737 Type as far as the FAA is concerned. 737-100 thru -900. You'd need to do differences training.5. You shut down the APU bleed when the APU isn't running to protect it from dual bleed and for its cool down/warm up period.

1) APU can run without pump running, on classics without options the battery start was always witout pump as the fuel pumps are AC powered.On some optioned classics and NGs there is a DC pump that runs automatically when the APU is started and will shut down when a main pump low pressure disappears (so it stops wen you turn on a AC pump, and it is working)If all pump fails, no problem, the apu is still able to feed itself.2) Badderjet answered completely3) As badderjet told you, the igniters wears with the usage, a turbine engine normally will self burn fuel without spark ignition if it is already started, fuel sprayed in the combustion chamber is mixed to the hot air, and will burn correctly, the flame is continous.However, to prevent flameout in some conditions where is possible or unwanted, we force the igniters to work, this will help us in the case of a flameout.We don't want to take too much time the igniters working as: the igniters will wear, the igniter boxes can fail meaning that when you need them they are broken.4) already answered5) APU bleed is a pneumatic operated valve, electrically controlled (on off). Witout pressure the valve will automatically close.However, to save APU life preventing to be loaded when it is just started, it is better to leave te bleed off for a minute after starting. It is not needed (but preferred) at shut down as there is a stop delay. If you see the APU, it will run for a minute before shuting down. In that minute the apu will be automatically unloaded, so the bleed and generator will be automatically turned off. But, if not touched, at the next start the bleed will re-open just when apu is at 100% running, without a delay, and this is no good.You must then prevent a dual bleed configuration, it is not dangerous if all is working correctly (expecially check valves) but is better to prevent them as annunciated by master caution and DUAL BLEED lights.

Surprised no one said this, but the pin is something done by the ground crew in RL, in the sim you don't need to worry about it.

But pilots must know (depending on sop) if it is used or not. With the wong procedure you may risk to damage the aircraft steering.