Questions tagged [fuel-consumption]

The amount of fuel an aircraft burns during a specified time period or for a specified distance; also known as "fuel burn".

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8
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1answer
206 views

What is the function of the aft stator in CFM's open rotor engine design?

CFM revealed their design for a open rotor propfan engine with two stages of blades - one active set of blades rotating in the forward and an static sets of blades on the aft. According to The ...
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1answer
98 views

What's the optimal cruise lift to drag ratio of the Piaggio Avanti?

I'm interested in the maximum L/D this plane can achieve. I can't find the necessary data to do the calculation myself. If I knew the "long range cruise" engine power and assumed 85% ...
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1answer
80 views

Is the FF (Fuel Flow) the fuel consumption index?

I am creating a program to calculate the fuel needed to fly and I need to know the fuel cost of the plane. In the boeing 737-800 (PMDG), on the display that shows the plane's systems, there is the FF (...
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106 views

What factors cause a turbine aircraft to have decreasing fuel burn over time?

Consider a fictional aircraft with a fuel schedule similar to the following: ...
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1answer
146 views

What is the fuel burn rate for climb of a C-130J Hercules?

I am trying to graph the payload range for a C-130J Hercules and I need an approximate value for fuel burn rate which I cannot seem to find online. Does anyone know approximately how much fuel a C-...
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1answer
134 views

What is the fuel burn of the APU on the CRJ900?

Looking for a reference from an FCOM, AFM or other manual for the fuel consumption per hour in pounds or kilos of the Honeywell RE 200 APU on the CRJ900.
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4answers
209 views

How do jet streams affect the fuel consumption?

I am trying to wrap my head around the effect of the jet stream on energy consumption as well as flight time. My understanding is that everything that has to with the flying part (vs navigation) ...
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0answers
38 views

Bleed air examples and percentages [duplicate]

I'm doing an assignment in GSP where I've got to examine bleed air and it's effect on thrust and fuel consumption. I've got to simulate 1-10% bleed air and then answer whether the drop in performance ...
6
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1answer
186 views

What are the engine-out implications of giant turbofans?

It seems that turbofans for civil airliners are improving fuel efficiency by building larger and larger fans that spin slower. For example, the RR Trent 800 introduced in 1993 had a diameter of 2.8m, ...
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1answer
385 views

Why are F-15s usually taking off with afterburners?

If there's no emergency, is it a big waste of money for military aircraft to take-off with afterburners? Why are they doing it, what are the advantages? Like here:
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2answers
170 views

Does airspeed impact fuel flow?

Let's say an F-104 Starfighter is flying at sea level at 600 KIAS with throttle at 100% RPM. Then, let's say the F-104 is still flying at sea level, but the pilot reduces throttle and airspeed falls ...
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516 views

What is the fuel consumption per mile for a full CEO A320?

I’m writing an essay as part of my GCSE HPQ and one of the statistics I need to base my research and answer on is the fuel consumption per mile or kilometre for a CEO A320. It doesn’t have to take ...
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202 views

Can thermals or high density altitude improve fuel efficiency?

Suppose a pilot is just cruising around building flight time. In order to get the most flight time for fuel, would flying on a dry cold day or on a hot thermal filled day save fuel?
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Can the plane Celera 500L be eight times more fuel efficient than a jet of similar size and capacity?

Celera 500L (see Otto Aviation site for more details) is a plane with a single propeller powered by a piston diesel engine. The constructor claims it is 8 times more fuel efficient than a jet of about ...
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1answer
210 views

How do I find out the fuel consumption of the PT6A for a lightly loaded aircraft?

The Fuel consumption of PT6 engines provided by manufacturers are as follows. Cessna Caravan - Consumption ~47? GPH. At full load at ~160? Kn. Quest Kodiak - Around 49 GPH at full load at ~170 Kn ...
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229 views

What is the ground idle fuel flow of an A320 (CFM or IAE or neo)?

Standing on ground, what is the idle fuel flow of an A320? ISA conditions, both engines running?
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5answers
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Has there been any attempt to use an underground cable system, a la a cable car, to tow aircraft along taxiways? [duplicate]

I've been looking at some proposals to try to reduce the time that an airliner's main engines are run at idle or near idle when taxiing to and from runways--a situation that uses non-trivial amounts ...
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2answers
168 views

Was it ever considered to optimise a jet to normally operate with one engine shut off?

As I understand it, the current trend to reduce all commercial aircraft to no more than two turbofans has long-relevant reasons – the more engines, the higher the fuel consumption – and earlier jets ...
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1answer
256 views

Why is the thrust-specific fuel consumption much worse for high bypass turbofans at cruise?

General Electric GE90 Takeoff: 0.278 lb/lbf/h (28.3 kg/kN/h) Cruise: 0.545 lb/lbf/h (55.6 kg/kN/h) Source: https://en.wikipedia.org/wiki/General_Electric_GE90#Specifications I assume this is typical ...
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2answers
293 views

How does fuel economy quantitatively depend on altitude for a jet?

We already have a few questions and answers about the qualitative effects of altitude on fuel economy: How do I determine the best altitude to fly for fuel economy? Why does fuel consumption decrease ...
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3answers
665 views

Which is more efficient: a jet engine or a rocket-powered engine?

Knowing that rocket powered engines have higher speeds than jet engines, it raises the question: are jet engines more efficient than rocket powered engines? This is of course in terms of fuel ...
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3answers
274 views

Why do turbofans go faster than turboprops? [duplicate]

Can someone explain why turboprops are less effective in terms of thrust than turbofans? But at the same time, why turboprops burn less fuel? For example, the Bombardier Q400/De Havilland Dash 8 has a ...
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1answer
226 views

Why use thrust reversers? [duplicate]

I see a lot of planes using thrust reversers and stopping in the middle of the runway in plane spotting videos, but I don't understand why they do it when they can obviously not use the reversers and ...
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1answer
4k views

Why would a B-29 consume more fuel at 17 kft than at 9 kft?

According to Wikipedia, one of the factors which almost caused B-29 44-27297 (Bockscar) to run out of fuel and crash at the end of its 9 August 1945 strike mission was the selection of an excessively ...
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3answers
449 views

Is it possible for a plane to be over fueled (and over-weight) to take off?

I've just reached my destination after 33 hours going from one European hub to another. A journey which usually takes a max of 6 from leaving my house! On the final leg of the journey, after boarding,...
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75 views

Fuel quantity vs. range

I'm just a Flight Simulator player with no real-life flying experience, so I apologize in advance if I'm asking a stupid question :) I watched a TV show and saw that certain courier companies (DHL ...
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71 views

Are measures taken to deliberately increase the fuel burn rate to lower the landing weight? [duplicate]

Just recently the Air Canada flight AC837 from Madrid to Toronto had problems with the gear right after take-off and they decided to abort the flight and go back to Madrid. It was a B767-300 (C-GHOZ) ...
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0answers
79 views

Average weight of fuel required to carry 1Kg additional cargo weight per hour [duplicate]

I'm looking for an average number here, I know there is not one correct answer as there are many parameters to take into account. Alternatively, I could also use something different, like : how many ...
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81 views

Fuel consumption database using ICAO codes?

I will preface this by saying I do not have any level of knowledge in Aerodynamics - I'm a freelance journalist and so apologies for the poor level of general understanding. I'm attempting to create ...
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2answers
252 views

Does burning fuel to get to your max landing weight violate any regulations?

Consider a hypothetical situation where where an unexpected tailwind will cause a flight to arrive at its destination above maximum landing weight. After reviewing all reasonable changes to altitude ...
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0answers
186 views

What is the specific consumption of an A320 at Mach 0.78 and 11,000 metre altitude? [duplicate]

I am currently doing a dissertation on an electric drive system on planes and I need help. I can't find the specific fuel burn rate for an Airbus A320; if anyone could help it would be great. Also a ...
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1answer
817 views

Turboprop vs Turbofan: How to compare Specific Fuel Consumption

I understand that Turboprop engines have a lower Specific Fuel Consumption (SFC) than Turbofan engines, on average. I want to see this for myself by analysis, ideally by comparing values of SFC for ...
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1answer
274 views

Why are there no large turboprop passenger airliners? [duplicate]

If turboprop engines are more efficient than turbofan/jet engines at lower speeds, and have a lower specific fuel consumption, why are there no large passenger airliners that utilize the turboprop ...
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1answer
623 views

What is the range difference between LEAP and PW1000 powered A320 and A321 NEOs?

Mounted on the same aircraft, PW 1000G and CFM LEAP are two very different engines, with different performances, that should have an impact on range. And we know range is a very important aircraft ...
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0answers
74 views

Do winglets really improve efficiency and reduce drag? [duplicate]

Below are some pictures of various fixed wing aircraft with winglets. It is widely accepted that these winglets will improve an airplane's performance by reducing drag and therefore improving fuel ...
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2answers
260 views

What is a jet engine's fuel flow at constant IAS?

Here is my assumption: In straight and level flight of a jet turbine engine: One IAS = One drag = One thrust = One fuel flow Therefore, the fuel flow will be approximately the same for a given IAS, ...
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2answers
10k views

What is the typical fuel consumption of a 737 in MPG?

What is the typical fuel consumption of a Boeing 737 in MPG?
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1answer
363 views

Does one-engine cruise consume less fuel than two-engine cruise?

Scenario 1. A two-engine airliner experiences rapid depressurization and makes an emergency descent to 10,000 ft, and diverts to the nearest airport. Scenario 2. The same two-engine airliner ...
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3answers
761 views

How much does it cost extra to fly with one additional passenger?

How much does it cost to fly an airplane (like a Boeing or Airbus) when there's one extra passenger there, at an average speed of 475–500 knots (880–926 km/h; 547–575 mph)? That is, about 100kg extra,...
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10answers
5k views

What is the most 'environmentally friendly' way to learn to fly?

As this question indicates, I've been thinking recently about the environmental impact of flying (since when automated cars are the only means of ground transport, aviation will be responsible for ...
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9answers
9k views

What is more environmentally friendly? An A320 or a car?

Presuming the A320 is at least 80% full (of passengers) and comparing it to a typical road car with 2 people inside, which one is more environmentally friendly, per passenger mile? I have attempted ...
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1answer
135 views

What exactly do winglets do? [duplicate]

I know that the winglets on planes like the Boeing B737 and Embraer E-190 reduce fuel consumption, but do they do more than that, or are they just for the stated purpose?
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2answers
247 views

Landing due to low fuel

If an aircraft has to make emergency landing due to critically low fuel. Who is responsible pilot or maintenance crew?
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6answers
4k views

Why cruise at 7000' in an A319?

I was on a flight from Philadelphia (KPHL) to Boston (KBOS), after some delay and some change of route due to weather, the captain announced that we will be cruising at 7000' due to delays in the area....
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2answers
799 views

How do I estimate piston aircraft fuel efficiency?

Is there any way to figure out or calculate fuel consumption of piston engines for aircraft? I'm looking at different engines in a book, and while jet engines have useful values like thrust, bypass ...
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2answers
1k views

What is the most fuel efficient climb speed for a C172 SP?

Assuming ISA, sea level, no wind, max gross weight, what speed would be most fuel efficient per 1,000 ft of climb? Alternatively, if that converges to the most fuel efficient cruise speed, when there'...
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3answers
334 views

How does the power distribution change for a turbofan engine from being stationary to going at full speed?

I have found out that a turbofan engine of say an F-16 is producing zero power when stationary since $Power = Thrust × Velocity$. But assuming that the engine is producing the same thrust, it appears ...
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2answers
143 views

How long will an aircraft need to fly before it can land without dumping fuel? [closed]

Now, I know perfectly well that the literal and unhelpful answer to the question is long enough to burn sufficient fuel that it is no longer overweight for landing. What I'd like to understand is ...
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2answers
92 views

Is the route which takes the least time always the one with least fuel-burn?

Geographically longer paths may require less fuel than the shortest (great circle) path. But what about time ? Is the most fuel efficient route always the one that has the aircraft in the air for ...
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4answers
337 views

Can longer paths consume less fuel than the (shorter) great circle path?

Is the most fuel-efficient route between points A and B always along a great circle ? Although somewhat counter-intuitive, this comment on an aviation blog seems to suggest that longer paths (in ...