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rwy12

Climb rate after take off

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Hi everyoneCould some one please tell me what is a realistic cliam rate after take off.I some time clock as much as 4000ft and have to struggle to keep it below with something like 747 pmdg-even with autothrust on.And also at what height do you start to level to the 1000-2000 rate.Many thanks for reading this and helping-I hope you will -:0Qas

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The climb rate depends on several factors. Aircraft weight, power available and air density are some of the more important factors to keep in mind when calculating rate of climb. As a basic rule for the heavy jets in FS, establish and maintain a climb rate of 1500' per min. at 250k to 3000' AGL, then increase to 1800' per min. to 10,000' while maintaining 250k. Above 10,000', increase airspeed to 300k and establish a climb at this airspeed. Your rate of climb will depend on your weight and air density. You will find that as your altitude increases you will have to decrease your rate of climb to keep an indicated airspeed of 300k. The important thing to remember is to keep your airspeed up. Do not sacrifice airspeed for rate of climb....instead sacrifice rate of climb to keep your airspeed, even if this means you can only climb at 300' per min. at higher altitudes.John MNote: the above numbers are guideline numbers only, not set in stone, and assume that your airplane is loaded to near max gross takeoff weight. You may find that you can comfortably climb at 2500' per min. right after takeoff all the way to FL250. As in real life, every flight will have different parameters that will effect the performance of your airplane.

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In the PMDG 747 you can derate the engines, to have less power available. Just see the manual.JohanA LITTLE LESS CONVERSATION, AND A LITTLE MORE ACTION PLEASE..

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Hi Paradise is spot on. Set your climb by achieving a given airspeed. Ultimately the rate of climb does`nt matter, as long as the speed is as intended.The climb rate will drop until, at the aircraft`s ceiling, the rate of climb will be zero, even with engines at max continuous power.CheersJames

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>Hi everyone...And also at what height do you start to level to the 1000-2000>rate.>>Many thanks for reading this and helping-I hope you will -:0>>QasThe general rule in flying is with a VVI of < 6000 fpm use 10% of the climb rate to start leveling off. So if you are climbing at 1500 fpm, start leveling off around 150 ft below your final altitude.If you have a rocket and are climbing faster than 6000 fpm, use 1000' before final altitude.

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The PMDG 747 with say 120 tonnes of fuel in it will not climb out at 3000fpm. It's more like 1000-1500 always. Quite a shallow, slow climb. So aim for those figures. The last 20% of the climb will be at <1000fpm. Even shallower.

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After take off one aims for a speed (usually V2 plus a bit) and whatever climb rate you get will just have to do.Upon reaching the acceleration altitude one starts trading climb rate for speed (to get the flaps up). Acceleration altitude varies by airline, around 1000 or 1500 feet seems common.Once clean the speed is yours... subject to any overriding speed constraints, of course.Hope this helps,Ian

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Climb rate is a function of excess thrust available. A jet that is lightly loaded has a great deal of excess thrust, and can climb quite fast in those conditions.For example, a Gulfstream-V can carry 41,000 lbs of gas and take off with a gross weight around 90,000 lbs...enough for a 11-12 hour international flight. But when flying a 1 hour leg, you might just take 8000 lbs of jet juice and have a GW of maybe 57,000 lbs. In that case the jet, if configured to climb using the FMS VNAV climb profile--even with the maximum flex temp derate--can easily hit 5-6000 fpm, which translates to a really high deck angle that makes people spill champagne all over themselves.I have friends that fly a specially-configured B747 on a lot of short legs (1-2 hours), and they tell me it'll climb like a Titan rocket even at maximum derate when light.The trick is to be a pilot...YOU are flying the jet, not the FMS. In cases like this you have to dial it back to something more reasonable. My real-world technique is to accelerate to 250 KIAS, and approaching 250 I select VS mode at 3000 fpm. I then manage the acceleration passing 10,000 feet manually, and engage FMS (VNAV) climb mode as I approach 280 KIAS (the VNAV climb profile speed). At 10,000 feet, the climb rate at rated climb thrust will generally be diminished enough to keep it below the 3000-3500 fpm range.But this idea that you have to just grit your teeth and settle for what the box gives you is hooey...you're in command of the jet, not some software engineer at Collins or Honeywell.CheersBob ScottATP IMEL Gulfstream II-III-IV-VSantiago de Chile

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Mnay thanks to all of you-I usally fly the 747pmdg on short hauls and it does go up like a rocket even when derated-sometimes as high as 4000+fpm.I will follow above advise and fly manually until higher up and thanuse vnav lnav.Qas

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Ah wait a sec here... The trick with flying the PMDG-747 on SHORT HAUL is this:1. Fuel it for LONG HAUL (eg >120 tonnes). This way you get proper realistic rotation speed around 175kts. Then you can derate properly and expect a good climbout profile.2. Somewhere in your Cruise, dump fuel. Dump enough so that your FMC reports a landing fuel of about 25T. This way you get a realistic Flaps30 landing speed around 145-150 kts. (Nothing will visibly change except the fuel figures on your PROG page).Ok, so it's convention out the window, but it does give you realistic performance when flying "short" 747 hops, which is really not it's optimal flight mode. But not everyone has the time to do every flight longhaul.

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>Hi everyone>>Could some one please tell me what is a realistic cliam rate>after take off.>I some time clock as much as 4000ft and have to struggle to>keep it below with something like 747 pmdg-even with>autothrust on.>>And also at what height do you start to level to the 1000-2000>rate.>>Many thanks for reading this and helping-I hope you will -:0>>QasHi!Try to hold a constant speed and not a constant VS. Forget about VS in that phase of flight as long its positive and above 500-1000fpm at all.AS some other already said, hold V2+10 or whatever is the best for 747. surly stated somewhre in manual.Fokker70/100 commands the pitch to hold 18

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>The trick with flying the PMDG-747 on SHORT HAUL is this:>>1. Fuel it for LONG HAUL (eg >120 tonnes). This way you get>proper realistic rotation speed around 175kts. Then you can>derate properly and expect a good climbout profile."Realistic" rotation speed, as in real life, depends on aircraft gross weight. The PMDG gets it very close to right regardless of the weight. Suffice it to say, nobody just sandbags an extra 260000 lbs of fuel just so their takeoff speed will "look right." This is pretty goofy advice.>2. Somewhere in your Cruise, dump fuel. Dump enough so that>your FMC reports a landing fuel of about 25T. This way you get>a realistic Flaps30 landing speed around 145-150 kts. (Nothing>will visibly change except the fuel figures on your PROG>page).And this is even goofier than para 1.RegardsBob ScottATP IMEL Gulfstream II-III-IV-VSantiago de Chile

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Florian wrote:>Try to hold a constant speed and not a constant VS. Forget>about VS in that phase of flight as long its positive and>above 500-1000fpm at all.>>AS some other already said, hold V2+10 or whatever is the best>for 747. surly stated somewhre in manual.This is only true for the "second segment" climb from gear up until the aircraft is high enough (for noise abatement and engine-out performance buffer) to accelerate to a normal climb profile. This transition usually occurs from 1500-2500 feet AGL and is aircraft dependent.>Further more the whole climb should be a constant speed climb>instead of a constant VS climb at all.No, not true at all. First, the climb speed will be restricted by the speed limit below 10,000 feet (250 KIAS), then most transport jet climb profiles specify a constant speed until reaching a climb mach number, at which point the airspeed will continuously change as you hold a set mach number for the remainder of the climb.The normal tech order climb profile in a transport is generally based on the most fuel-efficient climb to cruise altitude. If the jet is so light that a rated or flex-power climb results in climb rates and deck angles that are uncomfortable or marginally manageable (try gracefully levelling off from a 6000 fpm climb when ATC throws a sudden altitude restriction at you, for example) then the pilot certainly can, and should use some other technique to manage the climb until rated thrust performance isn't so extreme...normally after passing 10000-15000 feet MSL. >Climb rate is not as important as long as it is positive in>climb and the cabine can be pressurized fast enough.Not true when there are towering cumulogranite clouds all around you (or people shooting at you)...climb rate is an extremely important parameter when terrain clearance is a consideration.RegardsBob ScottATP IMEL Gulfstream II-III-IV-VSantiago de Chile

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Hi!Of course is all true you said, but as long you do not have any cumuluses or something you have to climb above, you surley agree to hold a constant speed climb.Fokker profile ist 250/280/0.70 Mach hold by pitch as long you do not change the tcatical climb mode to either faster travel or less fuel consumption. Since Fokker is not the most powerful aircraft VS varies between 3500fp down to 800, some slight increase when changing from ias hold to mach hold of coruse...Florian

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The best thing to do is refer to your aircraft's operation manuals because they should state what the best rat of climb is.

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not sure if anyone mentioned this but in a plane you never chase teh VSI, you climb at a given speed, and the rest will take care of itself... if you are loaded up lightly you will climb at 6,000 like in a 767 with a load.... if you are in a 152 you just go for Vy which will give you like 800 feet per minute with just you in it, and about 300-400 with two people in it...so go for the speed, never for the climb rate :)now if osmething is wrong and the plane is just not climbing like its supposed to, you might have forgteen the gear, or flaps, or something with the mixture/prop settings....you should always be aiming for Vy, and let the plane and physics do the rest :)

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