Questions tagged [fuel-systems]

Any question regarding aircraft fuel systems, how they work etc.

Filter by
Sorted by
Tagged with
0
votes
0answers
30 views

Are there design guidelines for sizing vent/surge tanks?

Could someone explain the sizing process of Vent/ Surge tank of Aircraft fuel system? I understand the Vent tank is to collect fuel overflow from the main fuel tanks. The reason could be due to Fuel ...
0
votes
0answers
50 views

Airbus a380 fuel system [duplicate]

Does the aibus a380 has center tank compare with a320,in this picture above,it shows that it has 11 tanks including the wings and the elevator while many aircraftshas together with the center tank (i ...
6
votes
1answer
592 views

Does the mixture and throttle setting affect the quality of priming of fuel prior to start?

This question is a generality. For airplanes with small reciprocating engines, does the mixture and throttle setting at the time of priming affect the quality of the priming or the engine start, or ...
1
vote
1answer
104 views

How do you lean mixture using only the instruments on a C172 Skyhawk?

POH manuals always tells to use the voice of the engine as a reference. (Which complicates things a little bit since carbs and fuel injected planes have different "reaction times" for each cylinder) ...
8
votes
1answer
221 views

Why was the Graf Zeppelin's endurance when fully fuelled with both fuels less than the sum of its endurances with each fuel separately?

The LZ-127 Graf Zeppelin used a unique dual-fuel system, with both a gasoline tank and a set of gas cells filled with blau gas; the airship could be flown using either fuel or both. The purpose of ...
0
votes
1answer
71 views

Why doesn't the Convair 580 have check valves to prevent inadvertent fuel transfer?

The Convair 580's fuel system is composed of two wing-mounted fuel tanks (one in each wing), each with its own shutoff valve (which can be closed to isolate its respective tank from the rest of the ...
2
votes
2answers
232 views

Why is the fuel pump in the startup procedure for a Cessna 172?

I thought fuel pumps were reserved for fuel injected planes in startups and during critical flight phases for all planes? However. There are some X-Plane flight tutorials that tells us to use fuel ...
6
votes
4answers
525 views

Why is alcoholic gasoline such a showstopper for aviation?

One of the main reasons the common avgas grades are still full of 3-plumba-3,3-diethylpentane is the incompatibility of many aircraft fuel systems with the oxygenates (primarily ethanol, with some ...
8
votes
1answer
327 views

Why would the outer tanks fuel on the A320 be colder than the inner tanks?

I have noticed in a number of instances during long flights typically over 5 hours the fuel in the outer tanks on the A320 are colder than the fuel in the inner tanks. This goes against the system ...
1
vote
2answers
248 views

Why are fuel pump switches separate?

Since engines are run only when the fuel pumps are on and vice versa , why are there separate switches for this? Why can't it be automated ?
4
votes
1answer
231 views

In normal condition, is the Airbus A320 APU fuel supplied by the main engine boost pump only?

I have a question relating to APU fuel system. As said in material, there are 2 system supplying fuel for APU to operate. 1st one is primary and 2nd one is secondary. In the 1st system or low ...
12
votes
2answers
2k views

Why fuel left/right when C172 is secured?

The C172 POH checklists say to set the fuel selector to "right" or "left" when securing the plane but "both" while operating the plane. What is the point of changing the fuel selector when the engine ...
-1
votes
1answer
282 views

Hydromechanical/Electronic fuel control system [closed]

Can someone explain the picture below which represents hydromechanical/electronic fuel control? What's the function of the solenoid on the picture below? What are the differences between solely ...
26
votes
4answers
13k views

Why didn’t the Captain of Cathay Pacific flight 780 shut down engine 1 and land with a more reasonable speed?

In the approach phase, engine 1 of Cathay Pacific flight 780 got stuck at about 70% N1 and it forced the crew to do an overspeed landing (230knots). Why didn't they shut it off by turning the fuel ...
3
votes
0answers
80 views

Could injectors be used as an alternative to turbopumps in jet engines?

Could injectors be used instead of turbopumps in aeroengines? Are there jet engimes that already use them? https://en.m.wikipedia.org/wiki/Injector
1
vote
1answer
124 views

What's this fuel line for?

Cessna 414 ram conversion What's this fuel line for that is coming to injector , other then the one from fuel disturbutor ?
52
votes
8answers
24k views

Why are fuel tanks located in wings?

Passenger aircraft have fuel tanks in the wings. Why? What are the advantages and disadvantages of this location ? examples of disadvantages I would suspect: added weight increases the structural ...
1
vote
2answers
1k views

Why does the cabin air sometimes smell of kerosene? [duplicate]

Why does the cabin air sometimes smell of jet fuel, although bleed air is tapped before it comes in contact with fuel ? How is this possible? I have smelled this a couple of times in my life (twice ...
4
votes
1answer
391 views

Why do the A320's centre tank pumps stop working 5 minutes after the low level has been reached?

I'm new here and I'm in training course for Airbus A320. In the training material, it's said that the centre tank pumps are controlled to stop automatically 5 mins after the low level fuel has been ...
1
vote
1answer
216 views

Does preheating fuel before it reaches the turbine result in a performance improvement?

Preheating fuel before it reaches the combustion stage was first proposed several decades ago as a way to improve mixture, fuel economy, and to reduce emissions in car engines. One example of this ...
83
votes
4answers
16k views

Why do we need to starve the engine before turning it off?

This question is for Piper Tomahawk, but I guess applies to any small aircraft. Why do we need to use the fuel mixture to starve the engine before turning it off with the key? Why can't we just turn ...
3
votes
3answers
2k views

Are there any 100% renewable energy aircraft in development?

There seem to be several options for aircraft R&D regarding cleaner fuels for the time when fossil fuels are no longer economically viable. Some of these include: Algae. A drop-in fuel. These ...
6
votes
1answer
252 views

Has fuel boiling ever been an issue for high altitude aircraft?

Are special measures being taken to prevent fuel from boiling inside the fuel systems at high altitudes? If so, when (with what aircraft) did this practice start? (question is pertaining to air-...
23
votes
6answers
4k views

Is there a tank priority sequence for using the fuel tanks?

Is there a tank priority sequence for using the fuel tanks, or does the pilot decide?
4
votes
1answer
696 views

Where is the APU fuel pump on the A320?

I'm looking for APU fuel pump location for A320 aircraft series. I'll be much appreciated if you provide a link to some images, schemes.
1
vote
1answer
223 views

Hydro-pneumatic fuel controls and hydro-mechanical fuel controls

What are the advantages and disadvantages of the hydro-pneumatic controls against the hydro-mechanical controls?
5
votes
2answers
237 views

Could hydrazine be used as a scramjet propellant?

Hydrazine is used a monopropellant in Satellite OMS rockets. But interestingly enough, it's highly exothermic decomposition into ammonia, nitrogen, and hydrogen provides heat for an endothermic ...
1
vote
1answer
730 views

What is the Specific Fuel Consumption of CFM56-7B24/26/27 engines?

I think the title completely says what I need. I use FSX (Flight Simulator X) to simulate flights and while flying the B738 I saw that it consumes much more fuel than the estimated amount, which is ...
1
vote
3answers
308 views

How the fuel in the wings is managed in case of an engine failure?

Consider an aircraft has fuel tanks only in wings (No central tank). Will the fuel for the respective engines will be consumed from the respective wings? In case of a single engine failure, if the ...
4
votes
1answer
713 views

Why does fuel vaporize in the carburetor?

So I get that a carb vaporizes fuel and mixes it with the air intake for the engine. But my question is what is the explanation for what causes the fuel to vaporize after it exits the fuel nozzle?
0
votes
0answers
345 views

What is the correct procedure for overwing fueling a CRJ200?

I have a question regarding overwing fueling a Canadair CRJ200. Let's say I was pressure fueling and one of the wings started venting fuel on the ground. The Crew Chief determined that I had to ...
1
vote
1answer
251 views

Could a kerosene fueled jet engine run on methanol without significant modifications? [duplicate]

Could a kerosene fueled jet engine run on methanol without sacrificing performance other than specific impulse? Would it require changes to the fuel injection/turbopump system? Would the combustor ...
15
votes
4answers
4k views

What could the fuel pump failure have been that my flight experienced?

I was on an Easyjet flight (I think an A320), when mid-flight, I overheard a member of cabin crew tell another passenger there was a 'technical' issue with the aircraft, that might make us slightly ...
1
vote
0answers
48 views

How do airblast fuel atomisers work?

How do airblast fuel atomisers work? Do they simply inject fuel with high velocity? Against the flow or perpendicular to it? How is the fuel jet shaped?
6
votes
1answer
1k views

How does the FAA define fuel capacity for ultralights?

Ultralights under FAR 103 are regulated to a capacity of 5 gallons. I'm wondering how exactly fuel capacity is defined, does it include fuel in the lines, and in the carburetor bowl or elsewhere or ...
0
votes
0answers
73 views

What's the difference between “dumping” and “jettisoning” fuel? [duplicate]

There are some countries (Sweden, for example), they do not permit "dumping" fuel, only "jettisoning" procedures. Is there any difference according to the amount of fuel that will reach the ground? ...
3
votes
1answer
470 views

Do Airbus aircraft fitted with ACT have additional fuel system controls?

Do Airbus aircraft fitted with ACT (Additional Center Tank) have a push button that controls the fuel transfer to the main center tank? If yes, where is it located?
0
votes
0answers
109 views

Alternate for jet fuel [duplicate]

At some point maybe after around 8 to 10 decades we may end up with a situation where the crude oil wells get drained up due to massive extraction and increasing demand for gasoline and ATF. What ...
2
votes
0answers
78 views

What is a possible reason for an L-1011 wing fuel tank overflow? [duplicate]

I was on a TWA Charter flight from Boston to Montego Bay Jamaica in 1989. During pushback from the gate, the right wing began to leak jetfuel (like gallons pouring out of the wing). They stopped the ...
9
votes
4answers
2k views

Is there any work on improving fuel tanks so they could store hydrogen?

I think that hydrogen is among the best fuels for use in supersonic and hypersonic flight, is there any work on improving fuel tanks so they could store hydrogen? What would be the best state to ...
6
votes
1answer
247 views

How is that there is no leak through the fuel vents during aerobatics maneuvers?

Can anyone tell me how aircraft such as jet fighters and stunt planes design the fuel tank vent system to prevent fuel leaking through the vents when performing aerobatics, 360 flips and complex ...
7
votes
1answer
1k views

Why not leave an electric fuel pump on all the time?

This question is related to single-engined piston airplanes equipped with an electric fuel pump like the Piper Dakota/Arrow etc. The POH states that the fuel pump should be switched on for takeoffs/...
2
votes
2answers
970 views

Was there ever a fuel-injected Spitfire?

I couldn't find one but did it ever exist? Would adding fuel injection have improved combat effectiveness or fuel efficiency?
2
votes
1answer
72 views

Are there any Part 135 (On-Demand Passenger Charter) companies out there that use Aviation Bio-Fuel?

I was recently approached by a client asking if I can provide charters on environmentally conscious aircraft that run on Aviation Bio-Fuel. Anyone have any insight on what is required for an ...
6
votes
1answer
241 views

Where is fuel metered in continuous flow fuel injection system?

How is fuel metered in continuous flow fuel injection system?
1
vote
1answer
662 views

Does an increase in inlet temperature affect fuel flow and power output?

The fuel flow rate decreases as the inlet temperature of the air entering the engine increases. Will the engine produce same amount of power as when the fuel flow was higher?
23
votes
2answers
6k views

Why are the center tank pumps deactivated when slats are extended on the A320?

Why are the center tank pumps deactivated when slats are extended on the A320? I researched about this and all I can see is hints. They say it is because of regulations or certifications.
2
votes
1answer
172 views

Is there a use scenario for the Detote value?

Im currently working on the fuel calculation of an airplane, when i stumbled upon a value called "Detote". When asking around, no one knew what the use case of this value is or why it even exists. In ...
40
votes
6answers
10k views

Is fuel moved around during flight on a passenger or cargo plane? If so why?

Is fuel moved around during flight on a passenger or cargo plane? If so why? Is balance an issue?
1
vote
1answer
129 views

Would fuel quantity indications be affected by extended flight at nonzero bank angles?

If flying with a 20kt crosswind requiring yaw input as well as roll input to maintain course, would the fuel indicators show different loads depending on the roll angle of the aircraft (in this case, ...