According to the GE website for the GE90-110/115 the engines ran at 127,000lb-thrust at "triple redline conditions" for 60 hours. So what you may be seeing is the difference between "maximum thrust" and "rated thrust". The GE90-110/115 puts out around 74-94,000lb-thrust.

@RonBeyer so the GE90 is rated at 115,000lb maximum and 94,000 continuous if I understood you correctly? The XWB-97 is rated at 430 kN maximum and 370 kN continuous. But, if we compare maximum numbers and not continuous, that means we're looking at XWB97 with 430 kN vs GE90 with 513, (although 569 kN was achieved once) - but thats only ≈ 80-130 kN difference, compared to the massive 60,000 shaft horsepower difference if we are to believe the articles.

Talking about jet engines in HP really doesn't make much sense, but media likes to do it. Power is forcedistance/time or ForceSpeed. So at 0 speed, you get 0 power. At takeoff speed and full thrust you get around 55,000 HP for GE90-115B, while your thrust actually decreases the faster you go. The actual fan shaft will transfer around 30,000 HP from the LP turbine to the Fan, internal to the engine.

@AdityaSharma "it takes more energy [and thus more power] to accelerate a mass from 100 knot to 105 knot than it does to accelerate from 0 knot to 5 knot ... or more time with the same amount of force? But the kernel of the discussion seems to be (somehow (by definition)) piston engines produce "power", and, as a generator, the GE 90 produces "power". Exploring the definitions and their applications is a delight and a hobby. I submit engine output is force. I find "Horsepower" definitions in aviation may be considered as such, enabling Thrust to be calculated as HP × $\eta$ for props.

@AdityaSharma so (without drag, in space) if thrust is constant, power will increase with velocity. Aerodynamic physics has this thing called drag, which was negligible when Watt developed Horsepower. My quest is to understand Horsepower as applied to aviation.

@AdityaSharma "a jet is ridiculously inefficient at low speeds"? Check out thrust specific fuel consumption of the GE 90 at take-off vs cruise (7.9 g/(kN second) vs 15.4 g/(kN second) ). It's just when engine torque is applied to turn a propeller instead of a fan, $\eta$ is even better at low speeds!!! So let's please dispense with this baloney that props are somehow mystically "constant power". Are they?

@RobertDiGiovanni For the purposes of this case, drag plays no role. Anyways, at 0 speed, TSFC has to be zero for a non-zero value of η. The GE90 may burn twice the fuel at cruise for the same amount of thrust, but it is still more efficient at cruise, because it now produces a non-zero thrust power (unlike when V was zero). Indeed the jet engine is ridiculously inefficient at zero speed: its thrust power and thus efficiency is zero! (practically, every engine has zero efficiency at zero speed).

Also, thrust does not decrease with speed if and only if the brake thrust power increases with speed.

@AdityaSharma so "thrust decreases with speed" is explained by a = (Thrust - Drag)/mass. This observation is correct. Eventually (Thrust - Drag) = 0: there is no acceleration.

@RobertDiGiovanni How is it explained by that equation? That equation explains why excess thrust (and therefore acceleration) decreases with V³. Why drag increases with V² (for a given $C_D$) is explained by $D = ½ ρV² \ C_D \ S$ , and why thrust decreases with speed (for a given power) is explained by $T = \frac {P}{V}$

(correction: that equation shows that excess thrust and thus acceleration decreases with V³ only in the ideal scenario, where η is constant)

@AdityaSharma I'll try one more time. With airplanes, one would not attempt to increase speed by by keeping power constant. Any propulsion system increases speed by increasing thrust. The output of any propulsion system is thrust. The amount of fuel required to produce thrust is $\eta$. Airspeed only affects thrust by $\eta$.

@AdityaSharma as speed increases, prop (and fan) airfoils become less efficient, eventually only mass movers. And there are Mach factors too. Look at the long, slender props of aircraft designed to fly around Mach 0.5, then look at the Progress D-27 (around Mach 0.7), then look at fans that are used at > Mach 0.8.

@AdityaSharma at 0 speed TSFC has to be zero? Well, T = P/V factors out V! I know, let's call P/V units of Sophit ... or maybe just thrust. Anyways, have a good day.

@RobertDiGiovanni 1) As speed increases, the thrust power of any propulsive device increases initially (the thrust power does even though the shaft power has remained the same). 2) As speed increases, propellers and fans become more efficient (with their efficiency being zero at zero speed, since no work is being done).

3) How does V factor out? At zero speed and for a non-zero thrust, we still have P that tends to zero. Therefore, if η was 1 enabling shaft power = P (thrust power), We can see that the shaft power must be zero for η = 1, and therefore the TSFC must be zero for 100% efficiency at zero speed.

I'll continue to try. Thrust has NOTHING TO DO WITH MOVEMENT . P/V = T. Thrust efficiency is affected by freestream interacting with the propeller airfoil. A jet at full standstill may produce thrust more efficiently at standstill than at cruise becuse delta mass flow velocity is greater. A prop because it's airfoil has Bernoulli as well as mass flow.

That's why propellers are more efficient at lower airspeeds. I think we have established thrust moves airplanes. Now we begin to understand effects of airspeed on efficiency.

Speaking in terms of "Power" seems to be unnecessary. No wonder the "jet set" dropped it. Aviation is equilibrium physics based on FORCES.

Simple as that.

Again i ask: show me one example of an aircraft that flies with constant power. Show me one example of an aircraft that can accelerate by reducing thrust?

Keep in mind I am from an applications world.

I know I need brakes on when I run up my engine and do magneto checks. What good does Power = 0 do me?

@AdityaSharma I really don't mean to be rude. I did some analysis of this a month ago thinking it is a shame that talking about propeller thrust seemed so taboo. I respectfully conclude that use of "power" may be based on a fundamental misunderstanding of "Horsepower". My finding is that torque/s is more applicable than Force x velocity FOR ENGINE "POWER" OUTPUT.

I believe this is the source of the misunderstanding. Notice how "fudgy" the inclusion of RPM in the formula as "seconds" (to make matching power units). Now we raise everything to power?

The plane, the sky, the Milky Way and Andromeda all rotating with the same power? Yes? No.