hi guys i have an question i have been searching this on google but i cant find it. how quick does the 787-9 climb after takeoff and then up to fl240. because first i used an site where i could see that but it hasnt have the one off the 787-9 yet so like how fast does it climb in VS to 5000 feet and then to FL150 and then to FL240?
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As fast as all other wide-body double engine aircraft do
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This depends on a number of factors, including weight.
I’m not familiar with the 787, however you should be looking up the N1% throughout the climb.
Most comemrical aircraft operators dont set a ‘VS’ they must climb to, but rather an N1 percentage. You then adjust the rate of climb to hold a certain airspeed at the set N1.
eg (just rough numbers, something along these lines as I stated, Im not familiar witht he 787 in the real world):
Initial climb out on departure would be between 2000fpm and 3000fpm. N1% would be between around 80% to 90%.
Once you cross around 5000 feet, you will generally reduce the N1% back to say 80% and reduce your VS. By this time, your flaps will be retracted. (if you want to get technical, often departure procedures at airports stipulate the rate of climb for noise abatement procedures etc)
So you keep the power at 80% N1, and keep your speed at anywhere between 210 and 250 until you reach 10,000ft. Adjust your VS to fit in these paramters.
Once you cross 10,000ft, you can lower your VS to allow your airspeed to gradually increase up to around 290knot IAS.
After FL180 (18,000ft) you will again lower your VS to allow the speed to gradually increase through 310 knots IAS etc and so on…
I would go online and search the operating manuals for airlines that use the 787, see if you can find a rough relative N1% for climb and cruise. You obviously wont be able to add in the Cost Index Number (thats another lesson) however you may be able to find some rough figures to climb out at
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but what do i need to type in google
http://wiki.flightgear.org/Boeing_787-8_Dreamliner:_Operating_Manual_and_Checklists
From this Wiki page:
Approx. Climb Thrust 89% - 91% N1
Max. Climb-rate (upto FL260) 1800 fpm CHECK
Max. Airspeed (up FL260) 300 KIAS
Max. Climb-rate (above FL260) 1000 fpm
Mach Speed upto FL300 0.8 Mach SET
Mach Speed above FL300 0.85 Mach SET
So, I was a little under with my estimations for the N1%. Simply set your N1% to about 90% through the climb phase past 10,000feet and adjust your VS accordingly to not ‘over-speed’ and to not ‘over-climb’ as per the parameters.
Remember most 787 flights are quite lengthy, so their takeoff weight (fuel amount) would be quite high. Dont forget to adjust your weight prior to takeoff to simulate the realism, otherwise you’ll be taking off way under-weight and be over-speeding and over-climbing with 90% N1. Prior to landing, you’ll need to adjust your weight to be under the Maximum landing weight as we dont have fuel burn, or big enough regions to simulate 787 flights even if there was…
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so on takeoff i set it on 2500VS and then climbing from 10000-FL180 2500VS
and then to FL260 1800VS
and then above FL260 1000VS
and then an another question do you gotta have your landing lights on until you are above 10000 feet or can you put them off after takeoff?
Not exactly, the point is to focus on the N1%, then the airspeed, then the climb rate.
Those climb rates are ‘do not exceed’ climb rates.
For example,
- Once you cross 10,000 feet. You need to make sure your N1% is at 90%.
- Make sure your airspeed is not increasing rapdily, you want a slow increase, slowly increasing so that it hits about 290knots indicated airspeed by the time you are crossing FL180.
- To adjust your airspeed, you adjust the VS. So if your airspeed is not increasing at all, reduce your VS until your airspeed starts to slowly increase. As you gain more altitude, you will need to continue to reduce your VS to keep your airspeed increasing.
For example you may have a VS of 2500fpm at 10,000 feet, but by the time you are at 17,000 feet, you may have had to reduce your VS to 1800fpm to keep your airspeed slowling increasing up to around 280 to 290 knots by this time.
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so for an examble i have my speed set at 200 on takeoff and then when i go above 4000 feet i set my speed to 250 and then i gotta watch my n1 to let it on 90% with the VS?
very informative thanks
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Basically, yes.
However I dont use the autothrottle (SPEED hold button) for climb out. I use my VS to maintain the correct speeds.
If I’m in the 717 for example,
Takeoff I set N1% to 88%. Once I’ve got a positive rate of climb, wheels up.
I then set my VS to 3000fpm and reduce throttle to about 70% N1. My speed slowly increases and passes 210 knots.
Crossing 3000 feet, at this time my speed is crossing 210 knots, I retract flaps.
I then simply leave my throttle at 70% N1 and adjust the VS to hold about 240 knots manually. By around 9,000 feet I believe my VS is about 2400 fpm
After 10,000 feet, I reduce the VS down to 2000 fpm, and still just leave the throttle at 70% N1. Because Ive lowered my VS, my speed increases again, passes 250 knots IAS and continues to slowly increase towards 280 knots. I havent used the SPEED hold function at all.
If you use the SPEED hold function, then your aircraft will constantly be adjusting the N1 to hold the speed, rather than adjusting the VS.
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ah ok nice i gotta test it out then
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hey i tested it out it worked perfectly i took off and i was at 90%N1 and then i adjusted my VS and i was at 2000VS and then when i putted my flaps up at 4000 Feet i slowed down a bit to stay under 250 knots but i had 2 options i could go more in VS then it would be around 4000 VS or slow down to 70%N1 what i did which option is better?
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can i climb more then 3000VS?
What site?
Not sure what your max rate of climb should be in the 787 - Someone else on here may know the real world answer. Id be looking at reducing the N1% before increasing the VS up to 4000fpm though…
Often landing lights go off above 10000 feet.
Why on earth would you keep 240 IAS? Speed up to 250! :)
No need to push the limits. Patience is a virtue my friend!
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250 is not a limit for most jets, no one stays at 240 below FL100. Flying is also about saving time.