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Beardyman

777 take off procedure

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I would like to ask for correct take off procedure.

This is something i have problem here.

My take off's are like rocket launch, i have big problems to keep speed restrictions.

 

What i do is when i line up at the runway i arm VNAV.

I press TOGA and plane accelerate with D-TO engine regime as set in FMS.

When i lift off, speed is increasing rapidly, especially with low fuel/payload.

Problem is that plane is accelerating all the way up to red limit, passing VNAV settings.

Should i press some buttons to keep VNAV regime after lift off ?

I do not want to turn on Autopilot just after take off, i like to fly initial phase manually, i need only assistance with speed control. 

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Are you following flight director commands? As long as you follow flight director commands, speed should be in perfect control.

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Engine derate is your best friend... I don't use the vnav for take off. I keep it in toga until i control the acceleration. And follow closely the flight directors as Christian mentioned above...

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Derate your TO and your CLB.
Doing the above has kept me well in check, the aircraft is extremely well behaved until 10k, then speed restrictions are lifted and all bets are off ;)
I also tend to hand fly it to about 15-20k (if the SID is interesting), and by following the FD commands, I've had no issues with restrictions.

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This is what i refer to.

If keep flight director guidance so to keep speed for example at 205 kts as some SID require, then i have to keep insane climb rate, cause just after lift off until 1500ft engines are working with take off power.

Even with D-TO take off power is huge.

If will not keep insane climb then will overshot speed restriction within seconds ...

Power managing is the biggest issue for me.

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Pull back more and get the flaps up You said it yourself, low fuel/payload. Derate engines or assumed temp. You don't ever need more than 95% n1 on takeoff, even at mtow if you've got a 10k+ foot runway.

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I'd derate to about 95-ish N1, I've had as low as 92.

Remember, ONE GE90 can power a 747 in cruise. These engines are massively powerful, 90% of their total thrust is still enough.

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This plane even with 90% N1 is having rocket performance :-)

 

I think normal take off climb rate - i mean usual and comfortable for passengers is somewhere between 2000 and 3000 ft/min, correct me if i am wrong.

Right now i do take offs manually, and simply after lift off, at about 500ft i reduce power and manually keep balance between climb rate and engine power.

It works well, only i think it is not according real life flying technique ...

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Real life in this airplane is having enough power to climb fully loaded (MTOW) to FL300 in just 18 minutes, light load, like about 200 T takeoff weight and it will climb to FL390 in 14 minutes. That is it. Just follow flight director commands and do not get distracted by how much you are climbing as that is not of concern. The passengers or the crew can not feel if we are climbing 2000 or 5000 feet per minute.

 

Climb is done at either CLB, CLB-1 or CLB-2 according to your weight and do not need to reduce that thrust setting, if you see the speed increasing you need to pull the nose up a littel bit more or simply follow flight director commands... That's is it.

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It isn't. The T7 is designed to be flown with A/T on at all times.
Nah, see, just after TO you should be pulling around 5000fpm, that's what I've experienced anyway. It's not a ridiculous nose up angle anyway, you should be at about 15 degrees nose up at liftoff then adjust to whatever the FD commands, that's how I do it.

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I mean usual and comfortable for passengers is somewhere between 2000 and 3000 ft/min, correct me if i am wrong.

Nope, it isn't. You can't feel the number of ft/min inside the plane. Whether you are climbing at 5000 ft/min or 1000 ft/min, you won't feel it.

However, if you were to go from 1000 ft/min to 5000 ft/min in a very small timeframe, you would have some explaining, and vomit cleaning, to do.

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I would like to ask for correct take off procedure.

This is something i have problem here.

My take off's are like rocket launch, i have big problems to keep speed restrictions.

 

What i do is when i line up at the runway i arm VNAV.

I press TOGA and plane accelerate with D-TO engine regime as set in FMS.

When i lift off, speed is increasing rapidly, especially with low fuel/payload.

Problem is that plane is accelerating all the way up to red limit, passing VNAV settings.

Should i press some buttons to keep VNAV regime after lift off ?

I do not want to turn on Autopilot just after take off, i like to fly initial phase manually, i need only assistance with speed control.

 

Are you sure your thrust levers are not overriding the AT reduced thrust commands? Go into the FMC and select the option "thrust levers override AT - never or in hold only"

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I usually fly with full payload, with whatever fuel load is needed for the trip. I usually derate to D-TO-2/Clb-2 and sometimes add a assumed selected temp to about 87-88% N1. If I'm heavy I go a little higher. With that I usually get climb rates to 20K in the 2.5 to 3.0kfpm range, and lower up to cruise. These engines are rockets, and I find I have to derate them quite heavily.

 

Tom Cain

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They 777 simply climbs like crazy.  It's nothing to be concerned about, since passengers can't tell how fast you're climbing.  Deck angle doesn't equal passenger discomfort. 

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I agree with 777 simmer, maybe the issue is that past 80kts when the FMA annunciates HOLD the throttles will reposition themselves to where you have set them, if it was full forward then you will see the thrust go right to the stops, as the AT servos are disconnected at this point and maybe unknowingly you are commanding full thrust all the time, even though you have set a DE-RATE or ASSUMED temp.

 

Furthermore, you might want to try a lower flap setting, flap 5 should suffice for most take-offs and the climb angle is shallower.

 

Also make use of the FPV or flight path vector during take-off it is very useful, especially if you are at light weights and high thrust settings. Use the FPV and anticipate your level off altitude, remember level off should commence at a rate of approx 100ft per 1000ft of vertical speed. If your climb rate is 2000ft/min you should start your level off at least 200ft before reaching your desired altitude.  

 

Since in normal ops the 777 is always flown with the A/T on, your A/T FMA should annunciate SPD when you are at your level off altitude.If you are in THR REF or THR mode the aircraft will keep accelerating. If you are in HOLD mode and your thrust lever is set full forward you will keep accelerating so check your settings and please try again.

 

When you level off your vertical mode FMA should annunciate VNAV PATH, VNAV ALT or ALT.

 

In real life the 200LR is also a real hand full taking off, our golden rule is to pitch towards 15 degrees nose up and then adjust our speed to maintain V2+15 to V2+25. A proper rotation rate will leave you at V2+15 to V2+25 every time!

 

cheers,

 

Karl

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Additionally, as noted, this idea that vertical speed is uncomfortable is a simism made worse by those stupid "passenger" programs.  The only time you feel something is acceleration.  V/S (vertical speed) is a speed, not an acceleration.  The change from level to any amount of V/S - more specifically, the rate of that change - would be an accelerative force.  So, if you change your V/S rapidly, then they'd feel that, but once established on a 1000, 2000, 3000, 4000, 5000, or even 6000 fpm V/S, they wouldn't know the difference.  The only way they could tell is if they noticed the difference in the angle of the force of gravity.  This is normally straight down the spine, but the change in the climb angle would change that gravity vector somewhat through the chest.  The ability for a human to discern that change, however, is slim to none.  They could tell that they were climbing because they're leaned back some (including cues by the inner ear), but the rate is not felt.

 

The takeoff profile is a pitch-for-speed regime.  Set power, rotate, and pitch to hold the selected airspeed.

 

 

 

 

Your vertical speed does not matter.

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(...)

 

 

 

Your vertical speed does not matter.

 

 

:P    Except for your passengers' ear pressure!!!   :P 

 

(Still they won't "sense" the V/S you're commanding.)

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:P    Except for your passengers' ear pressure!!!   :P 

 

(Still they won't "sense" the V/S you're commanding.)

 

 

Right...

 

Well, when you can find a passenger who can tell, or is discomforted by 2000 fpm versus 6000 fpm in a pressurized aircraft, you let me know.  :wink:

 

The regime of such high vertical speed is so short that the pressurization not keeping up argument is moot.

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Power and pitch equals performance. Basic Karmen airmanship. Remember, those GE-90's are the largest most powerful engines on any airplane. The diameter of those fans are larger than the diameter of a 737. Think about it.

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Here's a little cheat I'm using:

Until some 777 profiles are released for TOPCAT, and some less-powerful 777 models are released by PMDG, I'm using the 747-400 TOPCAT profile and plugging in my 777's takeoff weight + 100,000 lbs, which is about the difference in MTOW between the 744 and the 77L.  Flaps 10 will be Flaps 5 in the 777 and Flaps 20 will be flaps 15 in the 777.

 

Now I know that I'm not taking into account many many things; takeoff performances being based on limitations like deceleration rates before the runway end, engine out climb performance (in theory it's a 25% loss in a 747 and a 50% loss in a 777), the fact that these two airplanes are different in almost every way possible, etc.  But since this is just a sim and I'm not a fan of rocketship-like takeoffs, I'm sacrificing that measure of realism to gain a reliable (and lazy-man's) reduction in performance without chasing charts.  This method has worked for me in every takeoff scenario I've had so far.

 

Even on light-weight takeoffs, things happen slowly enough to be manageable by a non-professional such as myself.  :)  Thank you, Boeing, for de-rates!  Something the MD-11 didn't have.

 

-Tony Fiore

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It isn't. The T7 is designed to be flown with A/T on at all times.

 

 

Not exactly. Boeing may have intended that yes, but...

 

Some operators insist A/T on all the time. Some insist A/T off when hand flying approaches etc. And some leave it to the pilots discretion.

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