Questions tagged [aircraft-design]
Questions about the different choices that aircraft designers (typically aerospace engineers) make in order to create an aircraft.
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Why isn't the rudder below the tail?
Most airplanes have a rudder on top of the tail. When it is turned to the left, it causes the plane to yaw to the left. But it also puts a roll force to the right, because it is usually above the ...
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Are there any sources that contain information on the airfoils of the Boeing 737-500 and 737NG Aircraft?
I have found some information about this on airfoiltools.com (http://airfoiltools.com/airfoil/details?airfoil=b737a-il) but it doesn't specify the exact version of the aircraft, as the generations ...
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Why does the F/A-18 use external aileron and flap hinges?
As seen in the picture, the legacy Hornet uses ailerons and flaps with external hinges, and I was wondering what were the advantages of external hinges compared to flush hinges in the land-based ...
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Why does a helicopter that uses the Coandă effect need a direct jet thuster aswell
Why does a helicopter that uses the Coandă effect instead of a tail rotor need a direct jet thruster as well. Why couldn't they just vary the pitch of the ducted fan used for the Coandă effect?
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Lateral balance of single aisle planes with odd numbers of seats in each row [duplicate]
Do single aisle passenger planes with an expected odd number of seats in each row (e.g. 2-3, 1-2) where the aisle ends up not being central adjust the design of the plane overall to account for this ...
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Moving from 2D wing to 3D wing design
In terms of the design perspective of an Aircraft, once we decide on the airfoil that would be used for the wing, how would an Aerodynamics Engineer (or you) proceed to construct the wing? The ...
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what is the cross section of an elevator and trailing edge flap?
Is the cross section of both a Trailing edge flap and elevator an aerofoil please or, like i've shwon in in image below? I tried to find a side view of an elevator and TE deflected to see this for ...
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What is the specification of control cap (control tower) glass in FAA?
Does anyone know where I can find the specification of glass for control tower?
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Why are there no helicopters with the rotor mounted on the bottom?
Downwash from the rotor of a helicopter creates drag on the helicopter body acting against the lift force of the rotor.
Why are there no helicopters with the rotor under the main body of the ...
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Are there FAA regulations for designing new aircraft with pets in cabin?
I understand that these are FAA regulations on pets flying in-cabin on a commercial plane: https://www.faa.gov/travelers/fly_pets/cabin_pets
Let's say I wanted to design a new type of commercial ...
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Where should I start if I want to design a new type of aircraft? [closed]
I want to conduct informational interviews with individuals who work in aviation/aerospace to understand the various roles involved in designing a new aircraft and bringing it to market.
I'm curious ...
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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 differences would a helicopter designed to withstand many negative Gs have compared with a normal one?
There are a few helicopters that are able to take negative G's, and to this day only one can actually perform aerobatics (ie. Chuck Aaron's BO-105). The BO 105 is a rigid rotor helicopter that has ...
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How to calculate the amount of differential cable delay between a four port directional antenna and a single port Omni directional antenna in TCAS II?
I want to select the amount of differential cable delay between the top (4-port directional) antenna and the bottom (1-port Omni-directional) antenna in the TCAS II RBP-7G connector pin.
In the ACSS ...
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Is there an aerodynamic reason for airship fins to be at the tail?
I've read this interesting Stack Exchange question about why airships have fins:
Why do blimps have fins?
Which has me wondering why the fins are almost always located in the tail section.
After some ...
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How to calculate the Traffic Advisory (TA) range limit above the maximum altitude limit (take 16000 ft) of an aircraft?
Let us consider an aircraft(A) with 16000 ft maximum altitude limit. Above which it cannot achieve 0.25 G vertical acceleration with 1500 FPM. Now, my question is if there is an aircraft(B) flying in ...
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What are the air source settings for on the F-16?
As part of the start up sequence for the F-16, the "air source knob is set to NORM", according to this source:
https://theaviationgeekclub.com/heres-why-starting-the-engine-on-an-f-16-viper-...
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How is the wing area of an airplane determined?
Picture source is from here.
Here are wing areas of several airplanes. As we can see the Spitfire, B747-400, and Mirage 2000, their wing area are not rectangular. The line drawn from left side to the ...
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What can cause an unstable phugoid mode?
For clarity, I am wondering about how aircraft design can lead to the phugoid poles becoming complex with a positive real part, so an oscillation with increasing amplitudes.
My understanding of the ...
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Can vortex ring state (VRS) be solved by shaping the blades so that the vortexes they produce are weak enough not to form a vortex ring?
Vortex Ring State is one of the hazardous states a helicopter can find itself into. VRS happens when a helicopter has low airspeed (and usually hovering OGE) and is descending. If the helicpoter is ...
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How can I optimize galley space utilization?
I am working on a project aimed at improving the galley (inserts) of a commercial aircraft. My focus is on "" I have discovered that the galley often takes on a U-shape design, and the ...
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Delta wing RC aircraft unstable
I've been building and testing an tailed delta wing'd RC aircraft, but it has seemed that the plane is extremely pitch happy and tends to somersault when at high speed, is there some type of easy fix? ...
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Wing incidence angle of tandem wing aircraft
I'm trying to design a tandem wing model aircraft with both wings with the same wingspan. The front wing will have 2 and the rear will have 1 deg of incidence angle, also the front wing will have ...
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Why aren't ducted rotors used in gas turbines?
I am wondering why (for what I know) no gas turbine employs ducted enclosures for blade arrays on rotor stages.
I tried to search the internet for resources but I couldn't find anything related (so I'...
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Location on the wing where obstacles least disturb airflow
I have a model airplane whose wings I would like to fit with light strips top and bottom. These light strips would be across a significant portion of the wing's span. Without extensive study (wind ...
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Why do most light aircraft not have AoA indicators?
Why is an angle of attack indicator not commonly included on small airplanes? Is it too expensive?
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General Thin Airfoil Theory
I can't understand where the equation in the blue circle comes from or is derived from, I know it says the sum of the perpendecular components should be zero, but can you explain visually? and what ...
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Why does the maximum allowable load factor vary with airspeed in some aircraft?
In this ASE answer What is the maximum safe bank angle of a 747?, the author writes:
If we stay with stationary turns (without the "falling out of the sky"
part), the maximum bank angle is ...
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What is this thing sticking out under the F-22 Raptor's fuselage? [duplicate]
I was looking through some pictures I took of the Lockheed Martin F-22 Raptor performing a demo flight at Oshkosh 2023 and I noticed this thing sticking out from the bottom of the Raptor's fuselage. ...
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What are some of the advantages of inverse-tapered wings?
Inverse tapered wings are rarely used in aviation. The only legitimate plane I know about with inverse-tapered wings is the XF-91 Thunderceptor. So why aren't they used. What are the disadvantages of ...
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Where can I find whether or not an aircraft requires two pilots?
I am trying to build custom scenarios for myself and I wanted to know where is an exact place for me to look If an aircraft needs two pilots.
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Bulkhead (Forward and Rear) positions in civil aircraft
I am looking for general positions of forward and rear bulkheads in the civil aviation aircraft. Like, at what percentage of fuselage length from fuselage nose or any other reference point?
Any ...
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What does 3 blinking red lights on a small aircraft indicate?
I live by Lackland Air Force Base in San Antonio, Tx and have lived here 18 years and was also Airborne in the Ay and I just saw a small private aircraft fly above me with 3 flashing lights with 2 on ...
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Is the DC-6 Supercharged? And what is a Turbosupercharger?
What it says on the tin. Is the DC-6 supercharged? I thought all planes that fly above around 10,000-15,000 feet need forced induction, but wikipedia doesn't list the DC-6s engines as supercharged or ...
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How does wing sweep impact lift? [duplicate]
Given that swept wings (according to a google search) decrease lift, how much is lift affected? Why are they so commonly used in aircraft nowadays, like the SU-27, and subsonic aircraft like the ...
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Why in aviaton they are using Electro Mechanical Actuators instead of Electric Linear Motors?
In my opinion they are much more compact, the design may be needed to change in order to still be a fail-safe component, also, may be need to account for jamming and load disconnection safety devices, ...
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Amount of fuel consumed [closed]
Airliners have 200 tons of fuel. Assume less than 10 hr flights.
An airplane flying all day consumes 4,200 barrels in 3 flights. Us jet fuel consumption is 1.5 million barrels per day.
Is it ...
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PZL M28 Skytruck exhaust alignment
Watching a short documentary on PZL M28 Skytruck, I noticed it has quite oddly aligned exhaust pipes.
They point almost directly downwards, with only slight aft tilt:
Picture credit: Łukasz Golowanow ...
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Does the cross-sectional shape of a fuselage affect drag?
Comparing two bodies with the same streamlined longitudinal shape, and the same cross-sectional area, one with a circular cross-sectional shape, the other with a quadratic cross-sectional shape, ...
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What is the function of the cable from the front of the plane to the tail [duplicate]
In some older aircraft like the DC-2 an external cable can be seen running from the cockpit to the tip of the tail. Is this to control the rudder?
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Why does the trailing edge have a more pronounced taper than the leading edge on the Cessna 172?
Why does the Cessna 172 have a more pronounced taper on the trailing edge as opposed to the leading edge?
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Does the obstruction in a propeller duct increase exhaust pressure or decrease pressure/increase speed?
I came up with this question when looking through the answer for this question, which states that a convergent duct(obstruction) compresses the exhaust so that its pressure matches the ambient ...
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Anyone knows where i could find the McMaster, H. C., “FAR 23 LOADS”, Aeroscience Software, 2.02 Edition?
I am currently conducting research on wing lift distributions and came across the existence of a software tool called "FAR 23 LOADS," developed by McMaster, H. C. (Aeroscience Software, 2.02 ...
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Could floppy rotor blades be usable?
Autogyro and helicopter blades are more or less flexible, and when not stiffened by centrifugal force they droop noticeably. A extreme case would be that of fabric blades. They have been used at least ...
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Why there are no fully articulated 2 rotoblades helicopter
Why can't R22 and R44 make the 2 rotoblades fully articulated
Like cabri G2 helicopter but only 2 blades
So that easier to store in the hanger than 3 blades rotor blades helicopter and no mast bumping ...
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Why aren't Biplanes designs used when size and wing span restrictions are involved? [duplicate]
This research paper shows that for a given aspect ratio and wing area, compared to a monoplane a biplane produced a better L/D. So, wouldn't it make more sense to manufacture biplanes for subsonic ...
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Why do composite materials not decrease the OEW
Boeing states in an article, that the 787 Dreamliner saves around 20% of weight in a comparison to an aluminium based aircraft. Boeing 787 Dreamliner
When comparing the 787 Dreamliner to other "...
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Turbofan engine fan blade leading edge fairing?
A lot of aircrafts feature a leading edge fairing for the wing, at the connection with fuselage, in order to reduce the airflow interference.
Aerodynamically speaking, those fan blades in the turbofan ...
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How is the geometry of slotted flaps and slats designed?
I am currently doing a school research project attempting to find the effect of single-slotted flaps and slats on an airfoil's (NACA 2412 or similar) lift coefficient. I will be using a small homemade ...
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How can a passenger have opened an emergency exit on an Airbus A321 in flight?
Today it has been reported that a passenger managed to open the emergency exit door of an A321 in-flight. According to the report the aircraft (performing flight OZ-8124 from Jeju to Daegu in South ...