Questions tagged [aircraft-performance]
Aircraft performance covers areas such as the amount of runway required to takeoff or land and how fast an airplane can climb or descend.
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How much difference in drag there is between a feathered and non-feathered airplane?
Considering a typical twin like a Beechcraft Baron/Piper Navajo, if you lose both engines and no feathering is done how much drag will you have compared to if feathering was done.
Or in another way, ...
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STOL AIRCRAFT in Flight [closed]
Aviators here is a question. Can you land a "STOL" aircraft in a "C5A Galaxy" while both are flying?
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Why my 6DOF UAV Model is giving unrealistic variations in States? [closed]
I'm trying to develop a 6DOF Model for a UAV in MATLAB, I have created 2 m-scripts for that, one to implement the 9 equations (3 Rotational +3 Translational +3 Kinematic) and other m-script to solve ...
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Does an airplane fly less or more efficiently after a mid-flight engine failure?
When a multi-engine airplane loses an engine mid-flight, does it consume more or less fuel per distance travelled during the remainder of the flight with fewer engines operative? In other words, is ...
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How are individual spool optimal speeds determined in 3-spool engines like Trent 700/800?
I can see that in a 3-spool engine, the low pressure turbine and the fan have the lowest speed; The intermediate pressure turbine and the intermediate pressure compressor have another speed, and the ...
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what is best approach to make high thrust from nozzle side? higher velocity or higher pressure?
Producing high thrust form jet engine is not one step. Actually, there are many factors that can significantly play rule here.
Anyway, am focusing only on the nozzle side and its rule only in my ...
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Kvochur Bell Manuever practicality
I was wondering the other day if a Kvochur bell Manuever would have any modern day practicality since fighters no longer get into dogfights and most missiles have a range of 30+ kilometers. While ...
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Why do two similar planes with the same engine have such different performance?
Why do two similar planes with the same engine have such different performance? For example, the Ikarus C42 and the Eurofox both use 912UL engines, but the Eurofox cruises 15 - 20 knots faster.
What ...
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Is the centripetal acceleration when an aircraft turns related only to the load factor?
My question is about aircraft load factor and how it relates to turning ability.
I've recently come across this chart for the F-16 that shows the turn rate in degrees per second and the load factor ...
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Takeoff Distance Table: Aircraft Performance
When computing the takeoff distance on a grassy runway with a 9-knot headwind, should I first do the calculations for the grassy runway (note no. 5) on my ground roll, then apply the wind corrections (...
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Why aren't we using forward swept wings in commercial airliners? [closed]
What are the advantages and disadvantages of doing so.
Is there any practical problem in execution?
Provide some experiments for examples.
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Can any aircraft beat this car's 0-400-0 km/h record of 28 seconds?
In 2024, the KOENIGSEGG Jesko Absolut set a new world record for 0-400-0 km/h. That's starting from 0 km/h, accelerating to 400 km/h and then decelerating to 0 km/h again.
Without such easy rolling ...
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Can commercial aircraft be equipped with ECM and ECCM equipment?
I've came across an article recently about a commercial aircraft that was traveling from Madrid to Toronto and could not ascend to a higher altitude due to GPS Jamming.
With this apparent situation ...
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F15 Startup Intake drop
So I’m aware that the F15 has intake Ramps that adjust to airspeed and AOA, in order to ensure that the airflow is entering the engine smoothly and not too fast. But why does the system drop the first ...
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Does weight of an aircraft affect its ability to pull G?
This question includes the quote:
A C42 doesn't weigh much, so to pull the 5+ G required to exceed the design specifications of it's wing spar and fixings would require extreme speeds.
I'm not an ...
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How can I find the minimum and maximum airspeeds for efficiency with a specific prop/engine combination?
I'm operating a Cessna 180 with various wing and weight mods with a TCM IO550D engine and a McCauley Black Mac (D3A34C401/90DFA-2 3 blade (88 inch) seaplane prop. I operate Lean of Peak (LOP) for most ...
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How does the lift-to-drag ratio depend on absolute sizes?
A dependency is provided here
$$(L/D)_{\max} = \frac{1}{2} \sqrt{\frac{\pi \varepsilon ~ \mathrm{AR}}{C_{D,0}}}$$
AR significantly affects the outcome in this dependency. AR varies significantly among ...
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Why use the F-35
The F-35B has been troubled by "problems with its stealth coating, sustained supersonic flight, helmet-mounted display, excessive vibration from its cannon, and even vulnerability to being hit by ...
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What is the landing requirement for Klein Vision AirCar?
The Klein Vision AirCar is said to require a runway of only 1,000 ft and a speed of only 75 mph for take off.
But I cannot find any information on its landing requirement such as:
Minimum runway ...
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What was the fastest single engine plane with predominantly wood frame and fabric skin construction?
I've been doing some research and I haven't found a satisfying answer.
The Mosquito was quite fast but it was wood skinned and had two engines. The Bellanca Viking was fabric skinned but used a metal ...
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How much fuel can be saved in a half full of passengers plane?
On a typical airliner (let's say A320 / B737 / or similar), comparing a plane full of passengers vs one half full, how much fuel an airline can save on a trip when the plane is only half full?
(This ...
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Is there a valid case to do the imposible turn(180)?
It has been said many times not to do the imposible turn(180) after takeoff since almost always it ends in a fatal crash.
My question is, if you are flying a Cesnna 172, or any single for that matter,...
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Comparing a Flight In Turbulent Conditions At Va And Vb
First, let's cover definitions for both airspeeds:
Turbulence penetration airspeed (Vb) is the design speed for maximum gust intensity (i.e. the intersection between the 66 fps gust line and the ...
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Lift distribution of a swept wing with twist, dihedral, taper
I am trying to get the lift distribution of a swept wing with taper (in chord and thickness along the span), twist, and dihedral. I know that Kuchemann Index method is used for swept wings but I am ...
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How to calculate EGT Margin for P&W engines (PW1100g) ? (Theta parameter correction)
My goal is to obtain engine baselines and calculate EGT Margin for Pratt&Whitney PW1100g engines (specifically, PW1133GA-JM)
I have a large dataset of engine reports recorded during takeoff. I ...
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What is the precision of the Fuel Quantity Indication System (FQIS) of the Boeing 777?
What is the precision of the Boeing 777-300ER ultrasonic FQIS? If for example it is 2% when 100 tonnes of fuel are loaded, there could be anything between 98 tonnes and 102 tonnes. How is this ...
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Which airplane has the biggest ratio of Vne to stall speed?
Of airplanes that cannot hover (rotorcraft, VTOL), which one has the biggest ratio of $V_{NE}$ (speed that it may never exceed) to stall speed?
To be precise, "stall speed" here means the ...
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Can a single-bladed rotor with cyclically varying torque emulate a swashplate?
Instead of a swash-plate cyclically varying the pitch of the rotor blade(s), could a similar effect be generated by cyclically varying the thrust of the motor on a fixed-pitch single-blade rotor? The ...
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What are the correct Cd0 and Cdi values for a NACA 2412 airfoil?
According to an answer to this question, at best L/D the the drag coefficient is evenly split between Cd0 and Cdi.
I'm going to limit the question to the Cessna 172 and its NACA 2412 wing with an ...
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Computing the eigenvalues of the longitudinal dynamics _analytically_: is there a method to simplify the task, or must it be brute force?
I understand how to go about finding the eigenvalues and eigenvectors in principle, in order to distinguish the phugoid modes, but the first exercise in Lavretsky & Wise tells to compute those ...
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How/why does engine torque and horsepower affect aircraft speed? [duplicate]
I'm curious as to why torque and horsepower affect an aircraft's speed. AFAIK, it's only the engines RPM that affect speed, right?
Does this mean an engine's torque/horsepower only affects the speed ...
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How do you determine VMCG, if its yawing moment by the inoperative engine is only be corrected by the rudder?
The requirement of VMCG is:
VMCG, the minimum control speed on the ground, is the calibrated airspeed during the takeoff run at which, when the critical engine is suddenly made inoperative, it is ...
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Does the downwash velocity calculation apply to hovering flight? [duplicate]
After reading a very interesting interplay between two writers attempting to answer this question of helicopter downwash velocity, it occurred to me that, although this calculation:
$V_i = \sqrt{\...
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Where can I find aircraft design data? [closed]
I am looking for a library of different aircraft data, variables such as coefficient of lift, drag, etc.
I've gotten access to the POH/AFMS and the FAA TCDS' but they often modify the core data for ...
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Is less right rudder pressure needed for right chandelles
It is said on the Internet and the FAA Airplane Flying handbook that when rolling out from a right chandelle, the yawing moment is to the right, which partially cancelled some of the left turning ...
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Why single engine turbine helicopters can operate on higher altitudes than multi engine helicopters?
Probably you knew the example where H125 landed on Mount Everest (8848 m), and H145 highest landing was on Aconcagua (6962 m), almost 2000m difference.
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What is the effect of changing RPM on pitch attitude?
Considering a light aircraft like C172, what happens to pitch attitude of the aircraft when increasing or decreasing RPM?
And more importantly why this happens?
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IDLE Factor determination
The Flight Management System (FMS) utilises the Idle Factor to modify the computation of the vertical profile whilst descending.
During this phase, the FMS calculates the vertical profile and ...
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A transfer function relating jet engine thrust to pitch angle during a phugoid motion
Crossposted on Mathematics SE
I am doing a school project that requires me to find a transfer function that relates the thrust of a jet engine (which could change with time in one way or another) and ...
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Are UDF/Propfan Engines Thrust Producing or Power Producing? [duplicate]
For the purposes of aircraft performance (best endurance/range speeds, Vx, Vy, etc.) would a propfan be considered a power producing engine or a thrust producing engine?
I would imagine it would be ...
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For a fixed density altitude, how does climb performance depend on pressure altitude?
Below is the climb performance from the 1978 Cessna 152 POH, which I've plotted as climb rate versus density altitude. It shows that higher pressure altitude gives decreased performance even when the ...
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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 does Vx increase with altitude and Vy decrease?
As an airplane climbs, the best angle of climb airspeed (Vx) increases and the best rate of climb airspeed (Vy) decreases.
I can't figure it out, why does it happen?
I Hope someone explains it to me
I ...
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climb angle of 737-800 performance [duplicate]
I am doing a report on 737-800 and I have questions about its climb angle performance;
I am plotting a climb angle VS altitude graph for the aircraft, why does the climb angle take off at an angle and ...
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Why does the climb angle of 737-800 peak shortly after take-off before reducing again?
I am doing a report on 737-800 and I have questions about its climb angle performance;
I am plotting a climb angle VS altitude graph for the aircraft, why does the climb angle take off at an angle and ...
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Engine Performance Data for GE F414-400
I am currently in Capstone for ASE, and for our course we have been tasked with reverse engineering the X-59 QueSST created by NASA and Lockheed Martin. I am the propulsion lead for our team and I ...
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How would you know the difference between a compressor stall and a surge based on indications in the cockpit?
I understand the difference between a compressor stall and surge.
Stall: One or two blade stages exceed the critical AoA, the airflow is turbulent, and the smooth airflow through the compressor is ...
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Is my understanding about Balanced Field correct?
We have two definitions:
Balanced Field where Takeoff Distance Required = Accelerated Stop Distance Required
Balanced V1 = This is the speed where on a balanced field length (TODR=ASDR) if we have ...
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What are the effects of whiteout (snow) and brownout (sand/dust) on helos?
Is there any other effect besides low visibility?
Both seem to show very similar conditions.
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What type of ailerons does the Piper Seminole has?
I understand that the PA44 has differential type ailerons, but do they also have frise type ailerons? Making them a combination of differential and frise type similar to the Cessna 150/152/172 models?
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