Questions tagged [engine]

For general questions related to aircraft engines; use the [jet-engine] or [piston-engine] tag if possible.

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1
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1answer
280 views

Would a de-aerating fuel tank have any benefits?

I know turbine engines (bearings) are cooled by oil jets and that when oil is scavenged from the bearings it is more of a mist than a liquid, hence the need for various types of de-aerating this mist ...
0
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1answer
45 views

Why did Avianca have A318s with PW6000 engine?

I want to know about the upgraded PW6000 Avianca A318s. Why did those get upgraded? Did they not produce enough thrust already?
3
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1answer
952 views

Are there any programs to build a hydrogen powered airplane?

So called "renewable energy" is a buzzword these days. Auto manufacturers are starting to roll out hydrogen powered cars. Hydrogen may not currently be the most efficient or economic fuel for jet ...
4
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2answers
254 views

What turbine blade alloy did the Jendrassik Cs-1 use?

Wikipedia says that the first turboprop aircraft engine was the Jendrassik Cs-1 invented in Hungary by György Jendrassik. It says it was supposed to run at 1000 hp but "combustion problems" limited ...
20
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1answer
6k views

How could this weird shaped aircraft Airbus Beluga fly only with two engines and use short runways?

More than that! She could land and take off fully loaded on 2000 meters of runway at Hawarden Airport as seen here in this video. At my local airport the runway is 2500 meters long and an Airbus A300 ...
14
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3answers
18k views

How are engines mounted onto wings?

I've heard that the engines on a commercial air transports are typically mounted with 2 or 3 bolts. Is this true? If so, how big are these bolts and what are they made of? I'm optimizing a bolted ...
15
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5answers
14k views

Are turboprops more efficient than piston engines (thrust per fuel consumption)?

I want to compare two types of engines: Turboprops and piston engines. I want to know which one is more efficient. There are many types of efficiencies, so I will specify: thrust (in newtons) per fuel ...
3
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2answers
298 views

When evacuating after a rejected takeoff, what is the minimum distance you should be from the plane and which direction should you run?

In case of a rejected takeoff, and due to a malfunction or engine explosion, how far do you have to distance yourself from the plane and in which direction would you run towards? In my opinion (...
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1answer
140 views

Will an axial compressor work with an ideal fluid?

Will an axial compressor, like the one described starting on page 275 of this book, work if the flow was assumed to be ideal (i.e. incompressible and inviscid)? Specifically, what mechanism will slow ...
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3answers
170 views

What is the reason for this engine oil service procedure on a Bombardier CRJ?

Someone told me that servicing the engine oil on a Bombardier CRJ900 aircraft with the APU on could lead to the particular engine being overserviced. He then advised that the engine-oil service be ...
2
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1answer
190 views

Why can’t electric motors be used in aviation [duplicate]

Why can’t electric motors be used in aviation? Is it a problem with batteries, torque, or what? From what I’m aware motors at high torque are expensive and need a massive footprint, than a high rpm ...
2
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1answer
98 views

Are the “centerbody”, “fan hub frame”, and “intermediate case” all the same thing or separate parts?

I'm curious about the frames & cases at the front of an engine. I've seen OEMs call them the centerbody, fan hub frame, and intermediate case. Are these all the same thing or are these each a ...
14
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2answers
919 views

Components on engines, are they removed or blanked out?

As a follow up to why doesn't the A380 use outboard thrust reversers, if a component is not used in an engine, is it completely removed (hardware, wiring etc etc) or is it just made inoperative? In ...
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0answers
49 views

What are the differences between a compressor wash on wing vs on test bed

I work in an aircraft engine overhaul facility and I’m trying to understand the process of compressor washing engines on Wing compared to washing them in a test bed. What process steps are different ...
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1answer
115 views

Dual Ignition Systems

Is it possible to back up a single magneto ignition system using an electronic system on the same spark plugs rather than having to change to two plg heads?
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1answer
79 views

Does counter-rotating propellers on multi engine airplanes have critical engine?

I read from most of the article and books that counter-rotating propellers multi engine airplanes do not have critical engine, but it just happened to my friend who did his Commercial Multi Engine ...
27
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3answers
15k views

Does the cannon of the A-10 deliver more thrust than the engines do?

The A-10 Warthog is built around a 30 mm cannon that fires depleted uranium rounds, 65 of them per second. I heard from someone who worked on the flight controls a long time ago, that when the cannon ...
2
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1answer
94 views

Which is better: a rotor / prop followed by a stator, or contra rotating rotors / props?

It is all in the title. I'm interested in power absorbed/used for a given thrust, or thrust generated for a given power (same diameters of course). Just thrust and power. Ignore materials, electric ...
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5answers
9k views

What is the rationale for single engine military aircraft?

In aeronautics, redundancy is of primary concern. Having at least two engines is common for civilian aircraft. I expect the military to have at least the same level of redundancy. Moreover military ...
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4answers
180 views

Can i create a home built aircraft with this engine?

http://www.chiefaircraft.com/da-100.html Would this engine work for a homebuilt ultralight aircraft? I am still in the research phase, so i don't know what the weight of the aircraft will be, but I ...
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2answers
114 views

What engine should I use for a home-built ultralight (That is rideable) [closed]

I am looking for an engine that is powerful + cheap engine that will work in an ultralight aircraft and fly 1 person as well as the plane. yeah, this is kinda specific, but I have a tight budget and ...
2
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1answer
72 views

Is there an equation for jet engine efficiency as a function of turbine inlet temperature?

I know that there is a relation between the turbine inlet temperature and the engine's efficiency. But, can anyone provide an equation or efficiency as a function of just the turbine inlet temperature?...
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0answers
61 views

Where can PT-6 engine series starter-Generator diagrams be found?

Wondering if anyone can direct me to the spec sheet, diagrams, and breakdowns of a typical Starter-Generator for a PT-6, say a PT6-66 series or similar. And also who are the major manufacturers of ...
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0answers
63 views

What is the main difference between 'continental fuel injection system' and 'Bendix RSA fuel injection system'?

While I'm studying Aircraft Engine system, I learned that there are two dominant kinds of fuel injection system : 'continental fuel injection system' and 'Bendix RSA fuel injection system' I tried to ...
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1answer
92 views

What is nominal n1 and fuel flow behavior during cruise climb?

For a commuter airliner (e.g. 737) performing a cruise climb (step climb) at a constant Mach, how should n1 and fuel flow behave? I know that fuel flow should decrease with altitude (air fuel ratio). ...
3
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1answer
260 views

Which engines do airliners start first?

I noticed many planes, especially Boeings (correct me if I'm wrong anywhere), start engine "2" first and shut down engine "2" last. However, I was watching an Airbus A350 cockpit video when I ...
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0answers
77 views

Why are some exhaust cone exposed?

Some engines have an exposed tail/exhaust cone at their exit, protruding aft the nozzle. how does that affect the overall thrust and pressure distribution along the walls of the cone? is it's role ...
16
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7answers
9k views

How do rocket engines produce more thrust than aircraft jet engines?

I can't find the reason why rockets are able to produce so much thrust when compared to turbojets. I do know that the rockets carry their own own supply of oxygen since there is no oxygen in space or ...
2
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0answers
40 views

Are subsonic nozzle fully expanded?

this is about converging subsonic nozzles. Are they fully expanded? meaning exit pressure=ambient pressure? What about diverging subsonic nozzle? Are they fully expanded? what would happen if the ...
15
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9answers
20k views

Can an ultralight aircraft fly with a 18hp engine?

I have some questions - I'm planning on building single seat UL aircraft with this plan sketch (I have more), I drew this based on real plain and some research. Empty weight is between 50-70kg with ...
5
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1answer
249 views

Is there any mechanism in engine mount to prevent shock loads on engine while landing?

How engine is mounted in wing is restricting motion in any direction but is it still resistant to shock loads, or is there any mechanism inside engine associated to bearings that will absorb shock ...
18
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1answer
792 views

How do pilots do a preflight inspection of tail-mounted engines?

The recently released first part of an Air Clips documentary of a Lufthansa Cargo MD-11 FRA-NBO flight shows in some detail the pilot carrying out the preflight visual inspection of the aircraft (from ...
4
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2answers
92 views

How can the effects of hot corrosion and salt deposits from sea water spray in gas turbine engines be negated/prevented?

In aircraft operating in a maritime environment, corrosive effects from salt water are common. Are there any specific coatings used in engines for such aircraft? If so, which are they? How frequently ...
2
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1answer
162 views

Why Apollo 11 was launched in summer? (Performance question) [closed]

The question could seems stupid, but i think that best moment to launch a rocket is when temperature is lowest in order to achieve the best performance in a reaction engine. I do not know if there is ...
16
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4answers
6k views

Is it allowed to let the engine of an aircraft idle without a pilot in the plane. (For both helicopters and aeroplanes)

Is it allowed to let the engine of an aircraft idle without a pilot in the plane. (For both helicopters and aircr). Would there be a difference between a C172 and a 737?
47
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4answers
9k views

Why are many jet aircraft designed to cruise around FL350-370?

If the flight distance permits, the B737-800 will cruise at FL350, the A320 a little bit higher... Flying at FL370. Photo: Live from the Flight Deck by GolfCharlie232 (reframed) Elements such as: ...
8
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2answers
244 views

What are the durations of strokes and events in a 4-stroke engine?

I'm learning about engines, and I understand the basics of how a 4-stroke engine works, but I've seen lots of true or false questions such as "The power stroke is shorter than the intake stroke" or "...
16
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10answers
6k views

Can hydrogen gas be an alternative fuel source for a gas turbine engine?

I want to do research for an alternative fuel source for a commercial aircraft that will reduce the cost for flights. Will the hydrogen gas be ignited in the combustion chamber and produce enough ...
31
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2answers
8k views

What is the significance of 104% for throttle power and rotor speed?

I noticed this initially when learning to fly Robinson Helicopters but fail to remember the reason my instructor gave me; this again came up when watching a video about the ISS. In helicopters (...
2
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1answer
149 views

Are four-engined airplanes calibrated to put out the same thrust for both their inner and outer engines?

Is there a slight difference baked into the aircraft's throttle control systems or are they always pumping out the exact same thrust as each other?
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3answers
2k views

At what point is a turbine powered ducted propeller considered a turbofan?

Turboprop Propellers can be ducted for extra thrust. What are the criteria for determining that the engine is no longer a ducted propeller design, but a turbofan? Does there have to be a type of ...
14
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6answers
9k views

What's the use of so much torque on propellers?

(This question is closely related to this question) A typical Cessna 172 has a 180 hp engine, with a max. rotational velocity of 2700 RPM. Even small 1 hp electrical motors can achieve that RPM, and ...
5
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2answers
683 views

How much thrust could a 400 mm EDF produce?

There's a 195mm EDF from Schübeler that produces 25 kg of thrust at a peak power consumption of 15 kW: https://www.schuebeler-jets.de/de/produkte/hst Now, my question is: How much thrust could you ...
1
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1answer
487 views

Is overall pressure ratio same as compressor pressure ratio for a gas turbine engine?

For a typical gas turbine engine, turbofan in particular, is the compressor pressure ratio same as the overall pressure ratio? For modelling purposes can we use the same value of overall pressure ...
2
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3answers
898 views

125 cc engine, 64" propeller 3 blade, 180 kg gross weight, will it climb?

I'm a government teacher in school, currently I made an RC aircraft and flew it, now I'm working on a single engine light weight aircraft, I want to use a Honda CG 125 (single piston) engine, with 64" ...
3
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1answer
227 views

Are there modern airplanes with two propellers driven by one single engine?

Except 1903 Wright flyer, are there any other airplane using one single engine driving two coplanar propellers? Coplanar means push-pull and coaxial designs are not in the question's frame. Tilt ...
7
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4answers
1k views

Can wing-tip vortices be reduced/eliminated with a rear-facing propeller near the wing-tip?

Let's say we have a propeller-driven aircraft in the pusher configuration (rear-facing propellers). If we could somehow put an engine at the wing tip (ignoring structural concerns), and maybe make the ...
8
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3answers
11k views

How are engines numbered?

On a commercial aircraft, the number of engine is usually 2, 4 or 6. When the technician or LAE was given task to inspect an aircraft engine no 2 on a 4 engine aircraft. Which engine would they go to? ...
3
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1answer
166 views

Is there a standard install direction of the abradable shroud honeycomb on a CF6-80c2 engine?

Is there a standard install direction of the honeycomb cells on the Fan Forward case on the CF6-80C2 abradable shroud section? I have seen engines that the honeycomb cells run point to point front ...
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3answers
97 views

On a axial flow turbo fan or turbo jet engine what comes first the rotor or the stator?

I've been let to understand that one stage consists of a row of rotors and stators. But I'm not sure which comes first? Does the front fan blades make the first part of the stage (rotor) with a stator ...