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Guest william273

TO/GA

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i've searched the forums but can't find exactly what i'm looking for so thought i'd post it. most of my takeoffs are done manually but i tried using the TO/GA for takeoff in the default 747 { the switch is supposed to be on the throttle quadrant but i don't see it} so i use ctl=shift-G. i fly from the VC also. after i turn it on i get full power, pitch up and rotate then try to throttle back alittle but i still have full power. exactly how am i supposed to work this thing? are the auto throttles involved somehow? if so when and how to switch over and what about auto throttle settings as far as the TO/GA is concerned? any info at all on using the TO/GA would be a BIG help. thanks, william

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The default a/c are pretty basic when it comes to A/P A/T use but here goes anyway.You arm the A/T and hit TO/GA. This will give to take off power. You should reduce from takeoff power to climb power at acceleration height.....roughly about 1500 feet above airport elevation. In the default a/c you should do this by switching off the A/T arming switch, and moving the throttles on your joystick down a few notches until your N1 or EPR registers climb thrust. At the same time you throttle back you should lower the nose so that you continue to accelerate to say 240 KIAS. Lower flaps on schedule, and when you reach 240 KIAS raise the nose to maintain speed, all the time keeping the throttles at climb thrust. At 10,000 feet lower the nose to accelerate to normal climb speed (i think 320 kIAS on the 747) and again keep to that speed by pitch. As you climb you will have to advance the trhottles a bit to keep the same N1 reading dou to pressure changes.At some point in the climb you will hit your cruise speed in MACH. At that point use pitch to maintain MACH not KIAS. When you eventually reach cruise flight level, level off and switch the autothrottle on to maintain MACH. use Alt hold to maintain Alt.You can use the a/c in autopilot mode to do this by using vertical speed to maintain the airspeed you want.If this all sounds very complicated it is because the default planes dont have a sophisticated A/P + A/T. but this method will replicate how a real a/c climbs.For a better idea buy an addon such as the PMDG 737. Then you will find the A/P together with the FMC will handle all of this automatically.Good luckPeter

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that's exactly what i wanted to know. wasn't sure how that worked but i do now. thanks peter william

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just tried a test flight but it looks like the takeoff power it gives is for a FULLY loaded aircraft like the default settings. with 30% fuel in the left and right tanks and the others empty it shoots me straight to the moon. no time to click off the A/T and manually reduce power as by that time i'm well at or over 240 knots. using about 70-80% power manually for takeoff gives me a sweet exit off the runway depending on fuel and passenger weight, very manageable. i wish there were some power settings and such for the default aircraft like how they do for some of these addons.unless i'm missing something else i'll just stay with manual takeoffs. thanks again peter, william

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WilliamYou will learn a lot by flying manually to start with. You will learn that there is more to flying than letting the A/P and A/T do everything. I can really recomend the PMDG 737. Using the A/P together with the FMC (flight management computer) will take you to another level...literally. Unlike the default planes the PMDG model works like the real thing...the FMC will comand climb power at an altitude you tell it to, and will climb the plane at an airspeed you tell it to (this is not the same as how the default FS9 planes do it), and will level off at the FL you tell it to and will then change the A/T mode from CLIMB to SPEED mode....I could go on !But if you are flying the default planes if you hit F10 it will bring up a st of checklists and guidelines on what power setting to use etc.If you are new to FS9 I can also rcomend following the lessons in the cessna first. They can teach you a lot abot flight and navigation in particular

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i've been told to get anything by PMDG but my computer just won't run it so i have to use the defaults. i also like the defaults for the VC and smoothness. the checklists only show speeds for weights and not much on power settings except for fully loaded aircraft and i don't usually fly fully loaded. i just did another test flight with 2 tanks at 30% fuel and at 60% thrust, rotated at about 160 kts, watched the numbers climb slowly and smoothly up to 189-190kts. and held it there at a 10 degree pitch attitude easily for 1500ft then lowered the nose a couple of degrees to increase speed to 250 for being under 10,000. just watched a video on youtube of a 747 or a 777 don't remember which and saw his airspeed indicator do the same thing, move slow and smooth. unless your loaded to the gills i don't see a reason to take off using 90-100% power. i was suprised to see what 60% thrust could do. not sure how realistic it is but the readouts on all the instruments sure looked real and the whole takeoff looked and felt much more realistic. i'm not new to flight simulator. i've tried the lessons but get tired of old rod telling me i seem to be distracted so he's gonna end the lesson or he tells me to hurry up! something along those lines. hey if i'm slow then i'm slow... get used to it rod. he's ok though. maybe i'll have another crack at the lessons this weekend. william

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The only way to set proper take off thrust is to utilize D-TO (Derated Take Off). Under 99% of circumstances in today's overpowered HBR equipped aircraft DTO is used because there is usually no reason to use 100% thrust for takeoff. DTO is calculated by taking into account the aircraft weight, temp, QNH, runway length and wind to formulate the temp input variable that will cause the engine to perform with less thrust. For instance, inputing a variable of 60c will cause the engines to operate as it would at such a temperature range. The higher the temp, the less engine performance, the lower the temp the higher the performance. At Vmax the engines will operate at a lower thrust value thereby conserving wear and tear on the engines, saving fuel and you won't jump from 0 -250 before you have a chance to pull in the flaps. Mind you, there is a derate washout which will happen betwee 10 and 18,000 ft at which time the engines operate at normal thrust specs which you will need as you climb higher when loaded.This is all to say that you can't derate the engines in the default aircraft so manual TO/GA is recommended. One of the main complaints even on addon aircraft is that the aircraft is too overpowered and accelerates to quickly and this is becuase DTO is not being utilized properly. For this there is a DTO calculator.HTH,Mike T.

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hi mike. that's interesting stuff. now where can i get this tasty little morsel of a calculator? i'll do a search and see what i can find. as it is now the thrust i use for takeoffs depends on fuel weight but generally 57% up to 70% or so there abouts...90-100% never unless i just want to watch the airspeed indicators spin like a slot machine. thanks again for chiming in here with this. takeoffs are SO much smoother don't you think? william

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The TO/GA setting is controlled by:[autopilot]autothrottle_max_rpm=... in the aircraft.cfg file.It may or may not be set correctly in your aircraft. It sets the maximum N2 which will be used while the TOGA is engaged. This also controls the maximum RPM which the autothrottle will use when IAS or Mach is selected.-Pv-

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