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philbrown

Seemingly excessive climb rates on departure

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I'm currently mid-flight from Heathrow to Bahrain. It's about a 6 hour flight, and so I had about 120T of fuel (in lbs), with a ZFW of about 395T (again in lbs).As I was quite light, I set the derate to an assumed temperature of 60*C, and armed CLB-2. Yet when I took off, I went blasting through 250kts in a matter of seconds, and climb rates of some 6000fpm had to be used just to maintain the speed from running away until I reached the acceleration height, and the engines came back for CLB-2.I'm not saying that this isn't realistic - I don't honestly know. It just doesn't seem realistic. If a real 777 pilot comes on here and says thats right - fine.Also, when can we expect a load editor that allows us to alter the load in the cargo bay. This problem is in part due to the fact that using the default load ediotr, the maximum I can load using it is still some 60T short of the maximum ZFW. A post back in January said this was almost ready for release. Any news?? Or will it come after the current commercial priority of releasing the 757, and worrying about those who have already paid for the 777 later on?

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Please do a search of this forum. The speed/climb rate a low altitudes has been anwsered before. It is correct. RW T7 pilots will tell you that the speed/climb rates require careful management at lower altitudes. What do you expect with 115,000lb thrust engines on each side! The T7 needs that power at higher altitudes to get to cruise alt. Therefore at lower atltitudes, it must be watched closely.

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The real 777 does climb like a homesick angel - it scared the whatsits out of me the first time I flew in one.

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OK. Read lots of posts, including one advising using FLCH instead of VNAV on departure.But this still does not solve my initial problem. I find that the speed is increasing so quickly, that I am unable to maintain anything below about V2+40 without tail striking or yanking the pitch up violently once airborne. Thats even at full derate.I would be interested in hearing anyones advice in avoiding climbing at 6-7000 fpm (which can really annoy FsPax) until I get to acceleration height and the throttles come back to CLB-2 AND being able to maintain V2+10 (or V2+20).

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Do you have stabiliser trim set correctly for the CG? I ask only because you mention tailstrike with speed at V2+40, so I assume your 777 is not rotating properly.At what height do you start clean up and acceleration? Perhaps you are delaying that too long?Basically, if the aircraft is correctly trimmed before takeoff it should settle at about V2+10 hands off, with a climb rate dependent on thrust and weight. The higher the climb rate, the sooner you will reach acceleration height.Any lightly loaded twin will climb extremely fast initially. These high thrust 777 versions particularly so. So ultimately the answer may be to use higher weights. These aircraft are designed for that, and not for lightly loaded sectors.Maybe FSPax needs adjustment to suit the 777 actual performance, which can be quite startling :) As a real passenger I have never ever been bothered by high climb rate (high sink rate would be a different issue). What does bother me is an excessively slow climb, with the aircraft at the edge of its performance.Kevin

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> temperature of 60*C, and armed CLB-2. Yet when I took off, I> went blasting through 250kts in a matter of seconds, and the > engines came back for CLB-2.Arm TO-2 first (w/ your load I would have used TO-1), it should give you a derated t/o N1 about 92 % or so. Then you add additional assumed temperature derate as needed. Finally arm climb derate (which you did).A.G.

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I've considered this. OK for long runways - you get a short one though and the options become limited.I'm happy that this is a very powerful aircraft, but the speed builds up incredibly fast. The next I'll take a measurement of the acceleration.The main problem is, that once I get to VR and pull back on the stick, it takes a good few seconds before the aircraft is fully airborne. During this time, the speed is still shooting up, and by the time I've got 'positive climb' and gear up, I'm already blasting through 200kts, and only climb rates in excess of 500fpm will effectivly control the speed.Watching videos on the internet of 777 takeoffs, none of them seem rotate anywhere near as quick as I do, and their initial climb rates are also nowhere near the nose-bleed rates I am having to employ. Not the most scientific method of testing however.It just seems to me that it is maybe a little too overpowered. It's also the only FS plane I have that can overcome FS' annoying ground friction and actually taxy at idle thrust. And thats at heavy weight, from standing start - no throttle up at all. Brakes off, and it starts to roll.

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