Question about proper takeoff/climb procedure

Hey everyone,

I’m still practicing how to do a realistic takeoff and climb to cruise, but I’m struggling with a few parts.

Earlier today this was the SID I flew out of Dubai

Right now my current takeoff procedure looks a little like this:

  1. At VR, rotate and initial pitch up to 15°
  2. Around 1000ft AGL lower to the 10° and set climb power, retract flaps as needed, activate LNAV
  3. Once at 250kts I keep my climb power unchanged and set the VS autopilot on.
  4. Increase and decrease VS as needed until above 10,000ft, lower the nose and gain more speed
  5. Use VS to maintain until FL280
  6. Set my Mach climb speed and adjust the VS so autothrottle keeps the power near the climb power setting I used.

This is how I interpreted the tutorial on YouTube by @Tyler_Shelton

I’m just doubtful because today when I did this procedure, the initial climb was very quick and I found myself reaching up to 6600fpm (not constant but that was the highest I hit) to maintain 250kts and not go over. I reached over 10,000ft pretty quickly and as a result was going faster and faster.

This led to LNAV overshooting the fixes by quite a lot, basically swinging all the way around from DB570 and not stopping the turn until past UKRER halfway to VAXAB when it finally got on a stable course.

I was also way above the altitudes for the fixes, I don’t remember exactly but I think by DB576 I was already above 10,000ft (not sure tho so don’t focus on that)

I’m just unsure if this is a normal thing or should I adjust how I climb, or maybe even adjust my climb power?I notice as I got higher I need less VS at the same climb power, ultimately the last stage was around 100fpm climb for the last thousand or so feet.

I was flying a 777-300ER and climb thrust was 70% throttle (unsure what the N1% was), about 33% load. Idk if that’s too much power

Sorry for the long post! But I hope it makes sense what I’m asking clarification on, and I would like advice or tips if my technique is incorrect.

You have to realize the variables arent always going to exactly the same for every departure and thus, you’ll have to adjust. It seems like you’re flying pretty reasonably so maybe just make some flight adjustments to power/speed ect… You are also flying an aircraft with very powerful engines at a seemingly pretty light load, effectively making you similar to a rocket ship lol. Take not of that fact and adjust accordingly like I said… Happy Flying

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Thanks for the input :)

6,600 fpm is EXTREMELY fast. I’d say the commercial average is maybe somewhere around 2,500.

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That’s what I thought too, I think my climb power setting was just too high probably. VS was constantly changing tho so it’s not like I kept it 6600, but yea it seemed way too high for me but I was just following the tutorial

There are infinite flight topics that give you n1 and speeds for takeoff. I don’t have the link at the moment but they’re easy to find.

You still get a high climb rate though. I do a little less throttle and call it a “derated” takeoff.

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As @Altaria55 mentioned, you’d probably be more realistic limiting your climb rate closer to something like 2,500.

And because you have forward speed limitations (250kts below 10k ft, and also slow enough not to overshoot your waypoint turns), your only remaining option is to lower engine power.

I think the tutorial you mentioned recommends setting a fixed power and pitching for airspeed.

At the fixed power setting (the engine limitation), the power gets “spent on” two competing consumers of energy: 1)maintaining forward speed as the first priority, and 2)any energy left over goes into your climb.

And pitch manages the tradeoff in these two priorities from that fixed power.

But too much engine power (at recommended climb settings) relative to weight, means the only option is to reduce power further if you have the VS and IAS restrictions imposed on top of that.

So there is some dynamic adjustment in goals, depending on the situation.

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Thanks, I’ll try adjusting the power setting then

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I’m try figuring out for a while now how rl pilots are doing it. In fact, it’s a game and not reality. Maybe some things are calculated differently by the game. However I’m still trying to improve. Your settings are almost the same like mine. It sometimes helps me to set positive trim…. No doubt it feels not „natural“. Any further tips highly appreciated!

Trim has no effect on the OP’s condition. Trim counteracts pitch torque (the tendency for pitch to move on it’s own due to changing aerodynamic forces that are separated from the center of mass).

It’s a simulation of reality and as such the simulation does reproduce notions of physical law relationships between force, mass, energy and power.

For an accurate description of how these relationships apply to the OP’s question, please read my earlier post.

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I find trim helpful. It lowers the speed if used. So it prevents you to reach a certain height too early.

I meant that in real life other aspects come into play. That’s what I tried to emphasize here.

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We talk here about two things… As I understand, you trim to reduce the effort needed to maintain the stick / Device in the right position .
Sure it has an effect on the OP‘s condition … cause you increase your AOA if you set it too high on a lower speed

Okay and how can you explain me why I can go with a spitfire up to FL500 with Mach 3.0 ?
Just asking

Yes, you can trim up for a lower speed. More generally, your trim setting is always a setting that corresponds to a particular speed, whether that be higher or lower.

When you trim for a particular speed, the aircraft will seek that speed as a necessity of balancing all forces.

But in the case of the OP’s situation, weight is relatively low, making the default power setting too high in relation, which is revealed by both IAS and VS being too high (the extra energy has to go somewhere) to manage.

So in this case, trimming for a lower speed will only put more of the energy into VS rather than IAS. So the OP would still have the problem of thousands of fpm for VS.

But the problem, as I explained above, is managing excess power, as the reported symptoms are too high IAS and too high VS.

Trim will not help alleviated the excess power that needs to be dissipated - it has to go somewhere.

Outside of the flight model. But there are losts of boxes you can tick for how the Spitfire does behave according to irl physics.

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I agree with you here with regards to the trim aspect. Even with trim added, it would still be the same vertical speed, just with me not pulling my iPad back as much as I would without the trim.

I was following the profile for the 777 family I found here (forgot who made it) and set my climb power for like 5-10% below the takeoff power I used for the weight I was at. I guess with the 777 it’s still so powerful that at least at the initial climb phase, it’s better to use a conservative power setting.

Ultimately it seems to be a power issue, not related to trim as you said.

Edit: that guide was made by @DeerCrusher , I just adjusted the values from the 25% load a little just to make it a little more power and speed. I did 76% throttle then cut back to 70% which seems like too much when initially climbing in my case. So gonna cut back on that

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around 100 fpm for the last thousand feet

That seems very low, especially for a lightly loaded 777. Another thing to note is that in real life, climb power is not constant. As you get higher, the N1 creeps up closer to takeoff thrust. You can take advantage of this to prevent such drastic changes in VS.

I was also way above the altitudes for the fixes.

In SID/STAR charts, some altitudes are minimums and some are maximums (except for a few “mandatory” crossing altitudes), so I wouldn’t pay too much attention to them.

This led to LNAV overshooting the fixes by quite a lot

Seems to happen no matter what. Sometimes I take over roll control during a sharp turn— beginning the turn a little earlier.

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Oh, and one more thing…

Use VS to maintain until FL280

If you look at any flight on FR24, there typically isn’t a level off at some transition altitude. Although Infinite Flight changes from IAS to mach at FL280, you actually keep climbing at whatever IAS until your mach reaches your mach climb speed (usually ~M0.04 below cruising speed) while climbing. If you’re getting particularly good performance coming up on your mach climb speed, you can continue with IAS all the way to cruise mach.

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So I did two T/O runs in the 77W with the 33% load and 76% T/O power and setting to climb power at 70% as you did though I’m not experiencing the 6,600 fpm climb rate as you stated. I’ve reached around 3,800 on initial climb but after cleaning up and 70% climb power I can a manage a 3,500 fpm climb a little more/less while accelerating en route to 250 below 10k.

From what I understand, are you pitching down to 10 deg to reduce your climb rate and focus on reaching 250 knots before continuing your normal climb?

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This is an issue irl, not just IF.

One pilot’s description:
A Pilot Explains Waypoints, the Hidden Geography of the Sky | Condé Nast Traveler (cntraveler.com)
“The speed of a cruising airplane also means that we often do not get anywhere near a waypoint that is on our flight plan, because we must turn well before the waypoint if we are not to overshoot the route on the other side of it. For a sharp turn, in a strong tailwind, we may begin to turn 5 miles before the waypoint, something to imagine, that in a car you would start to turn the wheel so far before the intersection.”

There are similar discussions about waypoint tracking challenges for non-cruise phases of flight, on professional pilot forums etc.

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Yes I did pitch down, let it get to 250, but once it got to 250 I was pitching up again while at 70% so that the speed wouldn’t go over 250 below 10000ft. I guess maybe I did something wrong that I can’t remember. Once I’m at 250 I set the autopilot VS and then constantly move that up and down.

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I was actually just looking at the corresponding SID for this route I showed above, and yea I noticed the first point had a between altitude (between 1000 and 4000) and the next had at or above, and also they had speed restrictions and it also mentioned when the turns should be made and that it should be 25° bank angle (LNAV goes as far as 22° I think in IF)

I think along with reducing my climb power, I should be searching up the charts to get a gist of what conditions I should keep too

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