# What is Aircraft: Definition and 349 Discussions

An aircraft is a vehicle or machine that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. Common examples of aircraft include airplanes, helicopters, airships (including blimps), gliders, paramotors, and hot air balloons.The human activity that surrounds aircraft is called aviation. The science of aviation, including designing and building aircraft, is called aeronautics. Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, aircraft propulsion, usage and others.

View More On Wikipedia.org
1. ### Groundbreaking ‘blended-wing’ demonstrator plane cleared to fly

https://news.yahoo.com/lifestyle/jetzero-groundbreaking-blended-wing-demonstrator-095758254.html It occurred to me that the flying wing concept has been successfully demonstrated by Northrop-Grumman, and one could certainly build a scaled craft to test a concept.
2. ### B Inertia and flying

As someone who only knows elementary physics (so pardon me for maybe getting some things wrong), I have a question which troubles me and I'm having difficulties in finding an answer to: If a plane takes off at the equator and flies east to west, counter to earth's rotation, how it would be able...
3. ### I Effects of the centre of gravity on aircraft's stability

I'm working on a feasibility study for the integration of a liquid hydrogen storage tank for a Boeing 737-800. The tank weighs approximately 5000 kg and must be located towards the rear of the aircraft. I understand that this will shift the centre of gravity slightly further back and...

5. ### Boeing For the "757"/"767" type aircraft is there a way to calculate the vector forces caused by tilting the wings?

For any given angle, say if the wings were tilted 28 deg, how can I calculate the vectors acting upon the plane?

You may have noticed when airliners land or take off on humid days a fog or cloud develops on the upper wing. My understanding is that the upper wing has a lower pressure (Bernoulli's) than the atmospheric pressure (QNH) at the airfield. When the air molecules hit the upper wing there is a rapid...
7. ### B How does wind affect a turn for an aircraft?

First, I understand how wind effects aircraft tracking. I can do the calculations involving wind correction angles, effects on ground speed, headwind or tailwind calculations, etc. I teach it in a college piloting program. I am wondering how the ground tract of turn is effected by the wind...
8. ### Auto/Motor SkySurfer Aircraft - a personal multipropeller helicopter

Hunter Kowald designed and built the SkySurfer Aircraft. https://www.insidehook.com/article/tech/hunter-kowald-real-life-hoverboard
9. ### Algorithms for quadcopters to use back-EMF to detect obstacles close?

Would it help to study Verilog (VHDL) or Field-Programmable-Gate-Arrays (FPGA) if self-crafted x64/aarch64-assembly would take too much power/be too slow?
10. ### Ambiguous Problem Statement on Determining Speed of Aircraft

When I attempted this problem, I came up with two different solutions and answers, and both seem correct to me. However, the answer obtained by the first method is correct according to the book. The methods I used are as in screenshots below. Isn't the problem statement ambiguous, or maybe I...
11. ### Why doesn't aircraft weight affect descent angle in a gliding flight

It's a homework question, but I feel like it fits better in this forum. The solution fails to convince me because C_D and C_L can be both written in terms of weight: $$C_L=\frac{2W}{\rho v^2 S}$$ $$C_D=C_{D0}+k_1 C_L(W)+K_2 C_L(W)^2$$ Question: Solution: Any insight will be appreciated.
12. ### What are the drawbacks to "annular wing"/"super circle" aircraft?

By annular wing I mean something what is seen in this video. I'm fascinated by this design because it seems to lend itself to fluid entrainment and a greater lift profile for a smaller radius of wing. They are said to be quite stable.
13. ### Engineering Systems Engineering QFD on an Aerial Fire Fighting Aircraft

Hi everyone, I am currently taking an aerospace systems engineering course and right now, the focus is on Quality Function Deployment (QFD), which is basically a method driven by customer requirements, which can capture customer requirements and systematically convert them into engineering...
14. ### Rolls-Royce claims to have developed the world's fastest all-electric aircraft

https://www.cnn.com/travel/article/rolls-royce-worlds-fastest-electric-aircraft-intl-scli-gbr/index.html It looks like it has several innovations to help set these speed and time-to-altitude records, including the battery pack:
15. ### I How fast does an aircraft need to fly before it starts to glow?

As speed increases, the energy transferred from air friction must start to heat the aircraft. Eventually the plane will glow with radiating heat, such as a re-entering space craft. Presumably a plane can do something about this with cooling systems? Presumably there must be a heating limit to...
16. ### When did aircraft begin using systematic glide paths?

From watching internet videos about air crash investigations, I gather that modern airliners follow a set "glide path" as they land. When, in the history of aircraft, did such a procedure begin? For example, did the large planes of WW2 use printed documents or radio beacons that defined a...
17. ### Global Detection & Tracking any Aircraft Anywhere Anytime spots MH370

The "Weak Signal Propagation Reporter" (WSPR) has been used in combination with other tracking methods by Richard Godfrey to refine the initial path of flight MH370 in March 2014. That flight disappeared in the Indian Ocean and two extensive underwater searches were unable to locate it. WSPR...
18. ### Around which point does an aircraft rotate during the landing flare?

Without giving possible options, as to not lead people in a wrong direction perhaps, I have a question I am struggling with. Mostly because I get different answers from different people 🤔 When an aircraft is coming into land and starts the landing flare, around which point does it rotate? It...
19. ### Misc. Designing a Model Aircraft: Calculating Thrust and Lift for an Efficient Flight

Hello Everyone, I'm planning on designing a model aircraft that would be powered by an Arduino and electric motor. I'm interested in pursuing an aerospace degree and I figured the best way to get a headstart would be be to dive right into a project. This is also probably overthinking/overdoing...
20. ### Is this an antenna array on the new Chinese aircraft carrier?

I saw this photo at CNN.com today, and I'm trying to figure out what the function could be for what looks like a linear antenna array lining both sides of the aircraft ski-jump launching ramp. They look to be an array of about 10m verticals along each side of the bow, but with the base of some...
21. ### Typical surface roughness heights for aircraft surfaces

Hello! I am investigating some preliminary aerodynamics on a regional turboprop and for the drag model the surface roughness height of the airplane is required as an input. For this i do not have any data. In which range are the typical values for modern aircraft surfaces? Thanks a lot!
22. ### Celera 500L -- A much more efficient private aircraft

I saw this on CNN's website today: https://www.cnn.com/travel/article/celera-500l-plane/index.html The main claim is that the shape and overall design is more efficient than traditional aircraft design, and they are listing impressive fuel economy and operating costs. They say that the range...
23. ### Tethered aircraft lifting power, low gee world

I may have written myself into a corner. I am not looking forward to your answers. It involves the very core of my story, so I can't be coy with the deets. I know there are way too many factors for proper analysis, just looking for rough ideas. There are a couple of parts to this, I'll start...
24. ### Doppler radar measurement by an aircraft

u is the aircraft speed. c is light speed f is the initial frequency λ is the initial wavelength λ' is the apparent wavelength λƒ = u +λ'ƒ λƒ = u + (c/ƒ')*ƒ c = u + (c/ƒ')*ƒ u = c(1-(ƒ/ƒ')) u = 1500m/s The answer is half of it, where is my error?
25. ### News Brett Crozier, Captain of aircraft carrier fired

I was reading this news https://www.thedailybeast.com/navy-to-fire-captain-brett-crozier-of-virus-stricken-uss-theodore-roosevelt-who-begged-for-coronavirus-help As I'm far from good when it comes to understand english terms... what do they mean by fired? Does it mean just that he is no longer...
26. ### Guide to Aircraft Coordinates: Roll, Pitch & Heading

Hi, I’ve read a set of coordinate elements: „roll, pitch and heading“ for aircrafts. What’s the difference to „roll, pitch and yaw“? Senmeis
27. ### NASA NASA is going to assemble a quiet supersonic aircraft: X-59 QueSST

Press release The Concorde could only fly supersonic while over the open ocean - the sonic boom was too loud. NASA is looking for aircraft designs that are much quieter. While the X-59 itself isn't very practical for passenger transport it might have some direct military applications and help...

Hey guys, I have a job offer as an aircraft fitter(assembler? technican?). My job duties will be: drilling, reaming, riveting, installing hi-locks, reading and interpreting drawings, assembling aircraft parts and other. Can you tell me is there a future in this job?. I'm afraid that robots will...
29. ### B Hypersonic aircraft shock layer color

As a lot of people know, when things go hypersonic or even orbital velocities in the atmosphere, it’s going to get hot, scorching hot. The air emits black body radiation that are at the red spectrum (around 2000 to 3000 kelvins) sometimes goes yellow (5000-8000 kelvins maybe?) at re-entry...
30. ### VTOL Jet Engine Aircraft and VTOL Jet Engine

I am thinking about VTOL jet engine aircrafts like the following example (an ambulance). To be able to buid that kind of aircraft VTOL jet engines are needed. At the moment there are no VTOL jet engines available, but I have my own proposal: I have questions to jet engine experts. Is my...
31. ### Question About Electric Aircraft Propulsion

I have been thinking about this subject for some time now, based on the following considerations 1) Many companies are working on Electric Aircraft Propulsion, high energy density Li-Ion batteries are used to power Electric motors and they drive propellers. This is the approach every one is...
32. ### Current carrying capacity of a copper busbar in an Aircraft

"The surface of copper naturally oxidises, forming a thin hard layer on the surface which normally prevents further oxidation. " I've seen this in a book, higher level oxygen on busbar, means lower the heat and get away with ease, Doesn't it? So, Can I say a thin hard layer musn't be used?
33. ### Hypothetical Movement of Unidentified Aircraft

I know that the standard mantra of physicists who view themselves and their work as mainstream believe its never aliens. After all, as Carl Sagan reminded us, "extraordinary claims require extraordinary proof, " as it should rightly be. But, recently, some pretty extraordinary proof has made its...
34. ### Auto/Motor Centrifugal compressor lift aircraft -- engineering help please

Hello, I have a design for a different type of aircraft. I wanted an actual engineer to give advice before I fork over for some parts to try and make a working model. Attached are some pics. some of the pics are as if it were a full size acft. But for the model I was just going to use two turbo...
35. ### Can an aircraft using a geomagnetic field generate lift?

As shown in the figure, the aircraft includes a geomagnetic field convergence layer, which is a superconductor material. The geomagnetic field convergence layer repels the direction of changing the geomagnetic field, so that the geomagnetic field passes between the upper and lower converging...
36. ### Engine Type/Configuration and Aircraft Performance

Some jet engines have turboprop variants, and turboprops are rated in horsepower/watts just like piston engines. It's also possible for propeller engines to be mounted in puller and pusher configurations. While it's not possible to directly compare different engine types, what would happen if...
37. ### Using Aircraft & Balloons to Deliver 'Sunscreen' to Upper Atmosphere?

In the news we learn that aircraft (that don't exist) flying to 12 miles in altitude might be used to deliver "sunscreen" to the upper atmosphere. Could we use a carbon fiber fabric to make a strong, relatively lightweight, and flexible smokestack that might be supported by large helium lifting...
38. ### How does ion aircraft propulsion work?

I saw a video on youtube and it explains in a vague way how the system works, so there is a potential difference between two sets of electrodes and air between them is ionized in the presence of the E field but how muhc is it ionized? Because I get the impression that the ionization is not in...
39. ### Fluid flow over part of an aircraft wing

Recently, on a conversation with PhD in Engineering, I came to know that if, instead of the whole wing, air/fluid flows over part of it, then that will cause great turbulence and swirl. When I asked him for reference, he said that it can be found in any book on Aerodynamics. But still today, I...
40. ### Calculators Biometric devices in commercial aircraft

https://en.m.wikipedia.org/wiki/Biometric_device Do you feel it is useful to have Biometric verification & attendance system installed inside commercial aircrafts for aircrew staff? Thanks & Regards, Prashant S Akerkar
41. ### Extending an aircraft landing gear that has gotten stuck

Imagine an aircraft of which the its wing is connected to its landing gear by means of a hinge (joint), and then the gear suddenly gets stuck midway. If, subsequently, the aircraft makes a turn around its longitudinal axis (see picture), it seems to hold true that then the angle between the...
42. ### Range calculation for Airbus A320 aircraft

Homework Statement Hi to all, the Task I struggle with, is the range calculation from an Airbus A320 with the Breguet Range Equation which is defined as: Homework Equations R = (cl/cd) * (V/(g*SFC)) * ln(w0/w1) with V = velocity g = gravity SFC = specific fuel consumption w0 =...
43. ### About Sonic Booms and Quiet Aircraft

Hello, I am having this small confusion about sonic boom. Let's talk about aircrafts of the future -say having electric, noiseless engines (suppose). Essentially, these aircrafts practically generate no noise while flying. Now, if these aircrafts can travel faster than sound, will there still be...
44. ### Help Identifying AESA Antenna Structure Type found in the F-35 aircraft

This is the AN/APG-81 AESA Radar antenna by Northrop Grumman currently found in the F-35 (photo from wikipedia article). It seems to have a very different structure than past AESA/PESA antennas. For example the APG-68 from the F-16 looks a lot like stacked, slotted wave guides to me. So...
45. ### Aluminium corrode and aircraft fuselage

Describe how Aluminium can corrode or degradein Aircraft Fuselage. And methods for avoid degradation in Aircraft Fuselage. I don't know where to find any information on it at all
46. ### Is the world really better off without hydrogen airships?

An airship is any powered, steerable aircraft that it is inflated with a gas that is lighter than air. Hydrogen isn't the only gas usable for airships, but it is the only gas that really makes sense. That is because it has good lift to volume, is relatively inexpensive and is common as dirt...
47. ### Sound waves produced by an aircraft

Suppose that an aircfract somehow is not moving. Then I would expect the sound waves it produces to spread out uniformely in a spherical fashion. Now imagine a airplane traveling at approximately the speed of sound. In this case, if the airplane produces a wave at point A and after a time T the...
48. ### How to get greater lift from an aircraft wing

I want to know about how to get more lift from aircraft wings without increasing engine power and wingspan.
49. A

### Turbo-Jet Engine for Medium RC Aircraft

Hello , I am thinking to work on a RC aircraft ( Airplane ) that can load a small supply of Medical Firstaid in small range. So I need to make it fast and stable. So I'm thinking to use a small Turbo-jet engine in it which will be home-made. Please suggest me -- (1) Is that makes any sense ...
50. J

### Solving Aircraft Guidance in a Crosswind

I want to piggyback from this thread: https://www.physicsforums.com/threads/aircraft-guidance-in-a-crosswind.198836/ this is the question I am attempting to solve, however this thread has been locked I have found that you can express the two velocities the following way at any point in the...