Questions tagged [turbojet]
A type of jet engine where all the air passing through the engine is used to burn fuel and drive a turbine as well as generating thrust.
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Why are these characteristics of the FT-180 highlighted?
I have been checking the FT-180 engine used to establish speed record for remotely controlled aircraft (i.e. model airplanes). There are some specific features highlighted on the manufacturer site. I'...
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why you have to open 6 bypass valves in the J 58 engine?
I've noticed that the bypass valves in J-58 are opened after M=1.6. I don't understand why and what are the differences between the J-58 and a normal turbojet that reeaches more than M=1.6.
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Why does thrust differ in different reference frames?
If a jet engine flies with 4 m/s in the air and we want to calculate thrust for two different reference frames, can we prove that the calculated thrust for both reference frames are equal to each ...
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Why do we take into consideration holes for pressure thrust in jet engine calculations?
In many sources related to jet engine thrust calculations such as https://www.jet-x.org/a8.html ,
pressure thrust of a module such as combustion chamber, nozzle or compressor, is calculated by front ...
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twist correction of fan blades
How can the blade's angle be effectively adjusted to meet prescribed tolerances during shop repairs?
I am conducting a research paper on aircraft engine blade maintenance, and I have encountered ...
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Is diying a strong jet engine possible wih basic tools
Is it possible to manufacture a jet engine that provides 500 newtons of thrust with relatively primitive tools like a lathe or so , if someone did something similar can you provide me with the ...
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What were the main differences between Whittle's British turbojet and Von Ohain's German one?
I cannot fully understand in simple words the differences between the axial flow engine (Von Ohain) and Whittle's centrifugal turbojet.
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Do compressors and turbines in jet engines end with rotor or stator?
I am trying to understand compressor and turbine design principle based on stators and rotors.
I know that turbines and compressors both have a rotating and fixed section that constitute a stage.
For ...
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Why are inlet and outlet (exhaust) pressure considered to be the same in a turbojet engine?
Why do we take outlet/exhaust pressure (station 6) as the same as in inlet (station 1) ?
In T-S diagram, we see that outlet temperature is much higher than inlet temperature since flow in outlet has ...
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Where is the thrust of a turbojet felt? [duplicate]
At a high level, this is simple. Hot gas goes out the back, and Newton's third law says the engine is pushed forwards. But when you look inside the engine, it's less clear which part experiences the ...
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How do gas turbine engines and turbofan engines keep constant compressor side rpm?
How do the RPMs stay constant in a gas turbine engine? For example in car with piston engine, when you keep pressing the accelerator the rpms keep picking up, to keep the rpms constant you must let ...
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Why the green inside newer turbofan engine nacelles?
What is the purpose of the recent phenomenon of green being seen inside newer turbofan engine nacelles, just to the front of the fan blades?
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MIG 29 Engine - how to interpret these values?
I was wondering how powerful the engines of the MIG 29 are. On Wikipedia I found some specifications for it.
How is the mass flow rate calculated? I know mass flow rate = density * area * velocity.
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Logging Dual Received in a Single-Pilot Turbojet, FAA
Can you log dual received in a single-pilot turbojet on Part 91 flights if the PIC is type-rated, holds a valid MEI and instruction is being given?
Can the AMEL-rated student log AMEL category and ...
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How come a turboprop can't reach speeds as high as a turbofan?
I understand that turbofan powered aircraft can reach much faster speeds than turboprops like the C130 Hercules, and I can't imagine a turbofan turboprop powered 737 would be of any use really, but as ...
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Early turbojet RPM and thrust indicator
The flight operations handbook for the Douglas X-3 Stiletto (an experimental aircraft from the early 1950s) says that the instrument panel has instruments that indicate the thrust of the two ...
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How does a turbojet engine's performance change as the load on it varies? [closed]
What happens when the load increases on the turbojet engine? What senses the speed change in jet engines and how speed correction takes place?
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What does "military band" mean in this chart?
I'm reading the manual of J79 engine, and I just saw this chart:
Does anybody know what "military band" means?
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Why does J79 have speed more than 100%? [duplicate]
In the maintenence manual of J79 saw this table:
As you can see, there is speed more than 100% and it looks that the engine can handle it. Can't it?
One more thing, days ago, watched this movie: ...
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What does "time at temperature" mean in the maintenance manual of the J79 engine?
I was reading the maintenance manual of the General Electric J79 and saw these two charts:
and
What does "time at temperature" mean?
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Is axial bearing in turbo fan,turbo jet engines neutraly loaded?
Is axial bearing in turbo fan,turbo jet engines neutraly loaded,if yes then turbine/fan and compresor produce eqaul and opposite force?
If yes ,where then thrust come from,at internal walls,must be ...
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Do aircraft engines come with electric generators?
For turbojet/fan/prop engines, do they come with an electric generator when delivered to aircraft manufacturers, or it is something that the aircraft manufacturer has to find or make themselves?
I am ...
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Do turbine engines contain engine oil and fire-extinguishing fluid?
When aircraft turbine engine companies sell their engines to aircraft manufacturers, does the product contain the tank and pipe for engine oil and fire extinguishing fluid in the same package? Or is ...
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Do jet fighters use Turbojet engines, and do cargo/passenger aircraft use Turbofan engines? [duplicate]
I have a feeling that Turbofan engines are used in jet fighters and Turbojet engines are used in cargo or passenger aircraft.
Is my perception correct?
Do jet fighters use Turbojet engines?
Do cargo/...
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Overheating (fire thrown out of the nozzle) [closed]
At first I copied https://www.jetcat.de/en/productdetails/produkte/jetcat/produkte/hobby/Engines/P160_rxi_b
Where I manufactured and installed all the parts and they are very similar to the original ...
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How are compressor disks connected to the shaft?
I am trying to learn how compressor disks and shaft are connected each other. I don't have any idea about the terminology so I couldn't find anything useful.
Here is a section view of a sample and I ...
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Are there aircraft with multiple inlets for a turbojet engine?
Are there aerial vehicles which have multiple inlets with air ducts (shaped in S-forn) , which all lead the air to one single turbojet engine?
I have not enough space to put just one inlet area on my ...
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Why is the fuel:air ratio of a turbojet engine not around ~1:15 (the stoichiometric ratio)? [closed]
Also, what is the maximum fuel:air ratio possible in a combustion chamber of a jet engine?
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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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What causes the horn-like noise during the start-up of some jet engines?
Here's the specific sound I'm talking about (it starts specifically 56 seconds into the video, as well as at 2:02 for the second engine):
I've only really heard that ...
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Is the well known textbook-formula for net-thrust oversimplified or do I have a misinterpretation?
In order to understand how Jet-Engines works I came across the "famous" formula for net-thrust:
https://en.wikipedia.org/wiki/Turbojet#Net_thrust
$F_{thrust} = Q_{out} \cdot v_{out} - Q_{in}\...
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Do jet aircraft have a better glide ratio than propeller aircraft in general? If so, why?
Being fond of aviation, I play with software simulators a lot.
I have noticed that while jets seem to be able to glide for a long distance even at zero throttle, propeller aircraft need to be ...
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Can you identify this engine?
I am studying Aircraft mechanics currently, and in our academy we have some aircraft engines and different types of them, and I need please your help to know the reference of one of them, and if it is ...
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KSEE LOC-D conundrum
Consider the LOC-D at KSEE and note the Alternate Minimums criteria.
99.9% of the time, the winds strongly favor 27R;
The tower closes at 1900 PT currently (usually at 2100 PT non COVID times);
LOC-D ...
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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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Is it true that high-bypass engines are inherently inefficient at higher speeds?
Power consumption=Kinetic energy=$1/2mv^2$.
Thrust=momentum change=$mv$.
I keep being told that aircraft engines are most efficient when their exhaust velocity closely matches the freestream.
The ...
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Does jet engine exhaust velocity relative to itself remain constant despite speed changes?
Maybe this is a stupid question.
I seem to have been told, the velocity of the exhaust leaving an airbreathing jet engine relative to the engine, is constant despite changes in airspeed. However, to ...
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Rocket Thrust vs Air breathing jet engine why is a rocket better [duplicate]
What are design dynamics that give the rocket engine higher thrust than an air breathing jet engine of similar size in comparison to a turbo jet engine, turbo fan engine, high by pass turbo fan engine,...
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How do the contrarotating turbines work in the F-119-PW-100?
I was reading about the F22 Raptor and found out that its powerplants use contrarotating turbines. How does this work
Also, if the spools and their connected compressors are rotating in opposite ...
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Why did the B-52 never have a JT4A-powered version?
All versions of the B-52 use the Pratt & Whitney JT3C turbojet (except for the last version, the B-52H, which uses the JT3D low-bypass turbofan instead).
Problem: the JT3C is a horribly anemic ...
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What is the difference between turbojet and turbofan engines?
What is the difference between a turbojet engine and a turbofan engine?
I know that both of them have a fan and have turbines but how to distinguish them?
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Why is thrust available constant with speed for turbojet engines, when it varies with speed for turboprop engines?
Similarly, why is power available (nearly) constant with speed for a propeller engine, while it varies for a jet engine?
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What is the air/fuel mixture ratio in a turbojet engine?
How does it relates to stoichiometry ? What are the possible extinction accidents related to air/fuel mixture ratio ?
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How does an engine work when an airplane has $v=0$ on the ground?
I mean, for a turbofan:
$$ T= \dot m_{air,h} (1+f) v_{e,h}+ \dot m_{air,c} v_{e,c}- (\dot m_{air,h}+ \dot m_{air,c} ) v_0+ (P_{e,h}-P_{amb} ) A_{e,h}+ (P_{e,c}-P_{amb} ) A_{e,c} $$
but
$$ \dot m_{air}...
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Can a gas turbine be able to switch from torque to thrust?
Can a turbine engine be switched from providing torque (like a helicopter) to the rotor to transfer power to provide exhaust thrust (like a jet plane)?
Related: BV-347 upgrade this way?
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Why can't turbojets or turbofans be overtemped or overtorqued the way turboprops can?
Turboprops that aren't FADEC controlled can be overtorqued or overtemped if the power lever is moved too far forward yet I have never heard of a jet that can't be "firewalled", FADEC or not. Why is ...
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Are centrifugal turbojets easier to make than axial ones?
Looking at the history of jet engines, I noticed that the British first made centrifugal-types, but the Germans went straight into axial-types.
Which type is easier, if any? By that I mean, which ...
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What is significance of N1 and N2 in Jet engine? [duplicate]
Why N1 Low pressure compressor RPM and N2 High Pressure compressor RPM are monitored in jet engines ?
Why specifically compressor RPM rather than turbine RPM ?
What do N1 and N2 signify in terms of ...
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Why do we refer to "power" for turboprop engines and "thrust" for turbojet/fan engines?
In jet engines, I read that thrust is related to the fuel flow rate, whereas in turboprop engines power produced is related to the fuel flow rate. What is the reason and brief math behind this?
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When were the last subsonic turbojet-powered airliners retired from commercial passenger service?
The very first jetliners (Comet, Tu-104, Caravelle I-VI, 707-120/-220/-320, DC-8 series 10-30, original 720, CV-880) all used turbojet engines, turbofans not being available until later; when ...
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