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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RAT Deployment and Stowage
In this question, it states that the ram air turbine (RAT) deploys automatically on Airbus aircraft when there is a dual engine failure. Is there a way to stow the RAT in case systems are recovered ...
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What is the typical drag percentage of air intakes on a commercial airliner
I see several questions on the NACA ducts found on airliners Example 1, Example 2, Example 3 and I was wondering how much drag is normally generated by these inlets?
As they take in air, I imagine ...
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Can someone help me understand this aerofoil?
I came across this morphing aerofoil, but don’t understand how it works please?
Can someone explain also what the components are, like that box in the left?
I looked into that reference, but it’s a ...
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Is there an aerodynamic benefit of covering the underside of wings?
What is the nature and extent to the benefit of covering up the bottom of an airfoil?
It seems like all the early airplanes just had ribs and spars that were wrapped only on top, but then pretty soon ...
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Aircraft progress: Evolution or design? [closed]
This video of a Curtiss Pusher is stunning. Had I been around when it was new, I would have stopped there!
Question: What processes led to the aircraft of today?
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XFLR5 vs AVL vs DATCOM vs OpenVSP
I am working on a model airplane and am coputing some of the data using software.
I have already computed the general stuff using XFLR5 and AVL. My question is, is there any point for me to do the ...
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Why do some Caravelles have a full outboard wing fence, and some only a partial outboard fence?
The Caravelle has two wing fences on each wing, so as to limit the spanwise airflow (and associated tip-stall problems) that would otherwise occur due to its rearward-swept wings.
On most Caravelles, ...
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Why are most Caravelles' overwing exits so small?
Looking at a photo of a Caravelle, I was struck by how small its overwing exits were - they're almost as small as it's possible to be while still containing one of the Caravelle's windows, with most ...
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Why do some turbofan-engined Caravelles, but not all, have an anti-shock body at the root of the horizontal stabilizers?
Many turbofan-engined Caravelles have a prominent anti-shock body where the horizontal stabilizers attach to the vertical tail, about a quarter of the way up the latter. (Turbojet-engined Caravelles ...
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Why are turbofan-engined Caravelles' engine pylons open at the back?
The engine pylons of turbofan-engined Caravelles are open at the very back, looking for all the world like someone'd simply taken a saw and sliced off the rearmost portion of the pylon:
(Image ...
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Why would older jets and turbo props use electric gyros vs vacuum driven?
What is the reason for older jets and turbo props choosing electric driven gyros vs vacuum driven gyros?
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Is there any significance to the flap design on some Cessna citations?
In some business jets, I've noticed that the flaps seem to be split into sections. Here is one example on Cessna citation
As you can see, the flaps are split into three sections. The Embraer Phenom ...
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What is the difference between position and navigation lights on light training aircraft?
What is the difference between position and navigation lights on light training aircraft (or general)? When I search for both, I find the same lights: red on the left, green on the right, and white on ...
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Why do autopilot controllers use $\theta$ as the input signal rather than $\gamma$?
In particular, referencing how the Matlab/Simulink controller here uses $\theta$ (absolute pitch angle), rather than $\gamma$ (flight path angle). (Autopilot controller starts at 59:26)
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Why is the A330/A340's alpha-floor protection disabled above mach 0.53?
One of the A330/A340's several means of flight-envelope protection is something called "alpha floor" protection. In essence, if the aircraft's angle of attack is excessively high, TOGA ...
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Why was the nose gear of Concorde located so far aft?
Was this because of the drooping nose preventing it from being placed anywhere further up?
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How does propeller length, pitch, and airspeed affect efficiency? [closed]
tl;dr: trying to find propeller efficiency with thrust, velocity and power and see which propeller length to pitch ratio is efficient.
Hello, I'm a high school student working on an extended essay for ...
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Center of Gravity, Aerodynamic Center and Center of Pressure, how do they connect?
I read an article that described static margin by taking the aerodynamic center and the center of gravity. It explained why the center of gravity has to be in front of the aerodynamic center for a ...
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How does varying camber affects control over an aeroplane? [duplicate]
How does a trailing edge flap actually help an aeroplane?
It just changes camber but what does that exactly do that’s beneficial?
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Why do ATR aircraft have a dedicated power management selector for each engine?
ATR aircraft have a split power management selector in order to allow both engines to be commanded seperately.
Source: Magnar Nordal
but what is the purpose of having this facility? do pilots ever ...
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Literature request for effect of Aspect Ratio and Wing Sweep on critical angle of attack?
So I'm trying to find academic literature detailing how both aspect ratio and taper ratio affect the critical angle attack of an aerofoil - namely for a v. low AR wing (AR<1), and high sweep (~75 ...
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What should be the ideal distance between wings in a multi-winged air plane?
What is multi-wing or multi-plane:
For those who may not know, multi-wing air planes or multi-planes are aircraft that exceed the three sets of wings.
The idea is while increasing the number of wings,...
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The F104 tail pipe is not parallel to the runaway when the aircraft taxi.What is the reason?
The tail section is upward for clearance or to vector up the engine exhaust that will help to rise the nose when the aircraft take-off?
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XFOIL - Modify the gap at the trailing edge of the airfoil
I'm working on inviscid analysis flow in XFOIL. The trailing edge of my airfoil is too sharp, therefore leading to non-convergence of the analysis. Modifying the trailing edge thickness may do the ...
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How do flight controls work in tandem wing configuration?
If I understand it correctly, the usual configuration with tandem wings is that the front wing has ailerons - controls the roll. And the rear wing (a bit smaller than the front one) has elevators and ...
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Why ionocrafts (ionic propelld aircrafts) don't use electromagnetism to improve performance?
Well, ionocrafts use ion wind in order to propel itself in the air, but that needs a lot of surface area in order to work.
And since ionised gases can be magnetically manipulated, I was wondering if ...
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Why are the trailing edges of wings not always made as 'sharp' as possible?
I noticed that wing trailing edges of new airliners like A220 (CSeries) are not completely sharp. Instead, they are blunt. I always thought that the sharper the better in subsonic flow. What is the ...
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Subsonic Bump Inlet?
Contemporary high-performance supersonic aircraft such as the F-35 use bump inlet (alternatively known as DSI). These have a sophisticated 3-D bump that causes a 3-D weak shockwave in supersonic ...
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Why do the wings in these pictures go from swept back to parallel with the airflow? [duplicate]
To better understand my question, look at this A320 below
As you can see, the wing becomes parallel with the airflow at the wing root. Same thing on this 737
But this is not found on bigger planes ...
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Lifting-Line Theory - Numerical solution for a wing with dihedral angle
I'm trying to calculate lift for a wing with a dihedral angle using the Lifting-Line Theory. While using the thesis "Non-Planar Lifting-Line Theory for Fixed and Deformable Geometries" as a ...
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Is it possible to use a plane's entire wing as an elevon?
Would it be feasible to build an RC plane using the entire wing as an elevon, with each wing independently moved up and down with servos? For roll control, they would be moved in opposite directions; ...
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Could a Cessna Caravan be outfitted with Wi-Fi?
From what I understand, both ATG and satellite Wi-Fi require substantially large antennas to send and receive signals in large commercial airplanes.
Could a system like this be outfitted on a Cessna ...
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Why is the APU controller and ECB located aft without ventilation on Boeing and Airbus aircraft?
On Boeing and Airbus aircraft, the APU controller and electronic control box (ECB) is located aft. Why is it located here, where no ventilation is available?
Why it is isolated from different line-...
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Are there any aircraft that can engage thrust reversers above idle power setting?
Based on my experience with jet transport aircraft, thrust reverser levers can only be engaged after reducing the throttle to idle. Do any jet-powered aircraft exist that can engage the levers at ...
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Are airliners designed to land safely with no undercarriage deployed?
Complete undercarriage failure ("belly landing") is very rare in large passenger aircraft, but not unprecedented.
(source)
I would imagine it would be fairly easy to predict which part of ...
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Should the planform area inside the fuselage be considered for a stability calculation?
I am using lower order tools (xflr) for calculation of neutral point and CG location.I can think of modelling the wing in three ways
wing with section inside the fuse missing
wing with section ...
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How the placement of the pitot and static ports decided?
Forgive the this topic placement as it might be similar to other older ones (Although I a bit sure that the main contents might be different than other older ones).
In the upcoming days I will have a ...
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Examples of jet turbine values for combustions, fuel flow, Q of fuel, temp of exhaust, etc. for classroom use
I am trying to build jet turbine examples for a class and I want to use actual values for the mass flow of fuel and air, combustion temps, exhaust temps, exhaust composition (CO, CO2,H20,o2, NOx) ext…
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How is Airbus A320 cockpit philosophy designed?
I believe there is a reason behind a particular design especially in aviation.
I wanted to know how A320 cockpit was designed ?.
For example: Why is RCDR, EMER ELEC PANEL is on the left side of the ...
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Can commercial jet airplanes be designed to prevent a human from being ingested into the engines? [duplicate]
We've heard terrible news stories of humans occasionally being accidentally ingested into commercial jet engines. It is possible to design the engines in a way that would prevent that from ever ...
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What is the most efficient way to reduce interference drag when surface imperfections are unavoidable?
Interference drag can start to appear when there’s imperfections or excrescences on an aircraft outer surface. For example the following image shows some of these typical imperfections:
Source of ...
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Are Foward Swept Wings for a Rear Propeller Airplane Feasible?
Would going with a forward swept wing design, with the same cord and length of the "A Wing", bring more air the the propeller and tail to increase range, power, or stability?
Consider the ...
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Are there any aircrafts that use the same "ballooning effect" of spiders to fly?
For those that aren't aware, the "ballooning" effect that spiders use to glide (not necessarily fly) explaining in a simple way, some small invertebrates throw a bunch of long strings (in ...
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If they really wanted to, COULD they make a 100% fail-safe airplane? [closed]
With literally every single electronics device that I have bought in the last X years breaking very quickly or immediately, and being of horrible quality, this thought keep popping up in my mind:
If ...
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How are shock waves formed at fighter jet inlets when the shock wave is already formed at the nose cone?
If the main shock wave is formed at the nosecone of a jet aircraft at supersonic speeds, how is the airflow still supersonic at the inlet of the jet intake? Shouldn't the inlets experience subsonic ...
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Why do air planes not have a "grating" in the front of the jet engines for safety? [duplicate]
This is what a typical jet engine looks like:
Considering the horrible dangers with birds getting in there and crashing planes, why doesn't it look like this?
Why don't they have a "grating&...
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Why don’t ionocrafts (ionic propelled aircrafts) use ducted ionic thrusters instead of open air thrusters?
The most famous example of inonocraft is the aircraft with no-moving parts propulsion made by the MIT.
A problem of ionic thrusters is that they only generate a gram of thrust for every watt, which ...
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Are boundary layer diverters for jet intakes only required for supersonic speeds?
For subsonic aircraft (Mach 0.7), Is boundary layer diverter a necessary requirement for jet intakes? A lot of legacy aircraft were flying without them.
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Landing gear drag and weight calculations
I have read numerous books and researches, but I couldn’t find any formulae that actually work for how to calculate the following (for commercial aircrafts):
1- Drag coefficient for a retractable ...
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What exactly does "efficiency" mean in XFLR5 wing analysis?
Can somebody please tell me what it is / how is it calculated?
I initially thought it might be something with the Cl/Cd but I have another design with close to the same Cl/Cd, but with more than ...
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