New answers tagged aircraft-design
1
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can aircraft cruise speed be less than corner speed? my r-c PROPELLER plane calculations are saying cruise speed is less than corner speed.(Long read)
Nobody here is going to check your homework. Providing so much detail is not useful here. Likewise, posting excerpts from your professor's notes (perhaps these are your versions of the notes) is ...
- 15.6k
4
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Do carbon fiber wings need a wing spar?
Yes, of course they do.
One aspect of a spar is the transmission of shear between the upper and lower caps. If you put unidirectional fibers on the wing skin at the chord of the largest thickness, you ...
- 236k
6
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Do carbon fiber wings need a wing spar?
Wing structures made of an external surface of carbon (or glass) fibers and an internal honeycomb structure are virtually ubiquitous in the rotating-wing world i.e. blades for helicopters and wind ...
- 14.7k
13
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Do carbon fiber wings need a wing spar?
Yes that's actually how modern airliner wings are made, aluminum OR carbon. The entire "wing box" between the leading edge and flap/airleron is the "spar". The upper and lower wing ...
- 134k
2
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Accepted
Do carbon fiber wings need a wing spar?
Small carbon-skin wings for race cars often omit a spar. Sometimes their core isn't even rohacell honeycomb, just styrofoam.
Bigger wings like the A350's need a (carbon) spar, though. Even larger ...
- 12.6k
-1
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Which aircraft has the simplest folding wing mechanism?
In addition to the aircraft mentioned in the answer above, I found another one with a simple wing-folding mechanism. The ICON A5 sports aircraft: It certainly isn't as simple as the Onex kit plane by ...
- 1,562
7
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Accepted
Are there carbon fiber wing spar pins?
Not that I know of, and at first glance it seems like a bad idea.
Carbon fiber is great in tensile strength (and compression, if properly supported), but spar pins are mostly loaded in shear. In ...
- 236k
3
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The feasibility of using wind turbines to construct a giant quadcopter
Motors and generators are essentially the same thing, there may be some modifications required, but it would not substantially change size, weight, power, etc.
The motoring efficiency would be very ...
- 15.6k
3
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STOL AIRCRAFT in Flight
Not saying such a thing would be totally impossible, but nope.
Look up the width of the cargo bay of a C5, then look up the wingspan of your favorite STOL plane that you had in mind for this question.
...
- 27.2k
11
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Accepted
Is the front wheel supposed to turn 360 degrees?
Note how the wheel steering linkage (arm) has been disconnected:
The wheel freedom is limited to about 80°, the arm must be disconnected in order to go further. In this video, while this ...
- 77k
2
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Is the front wheel supposed to turn 360 degrees?
Some airplanes have nose wheen steering, some do not.
Nose wheel steering does not allow the nose wheel to turn full 360 degrees, unless the steering system is disconnected from the lower assembly. It ...
- 30k
1
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Purpose of Reflex in Flying Wing Aircraft
For stability, ask yourself how forces and moments will change with a change in angle of attack. In other words: Do not look at the force equilibrium, but at its derivative with respect to angle of ...
- 236k
2
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Purpose of Reflex in Flying Wing Aircraft
A tail surface just aligned with the airflow to move the aerodynamic center back just creates a very stable ballistic missile or lawn dart. To fly, you have do things with the stabilizing surface to ...
- 134k
1
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I don't quite understand the derivative in this vertical wind gust formula
The derivatives are the same because it doesn't make a difference what causes the change in angle of attack.
Normally, a plane will change its angle of attack when it maneuvers or changes speed. In a ...
- 236k
2
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I don't quite understand the derivative in this vertical wind gust formula
The slides are indicating how lift coefficient $C_L$ changes with angle of attack $\alpha$ a few ways.
First, they conceptualize it as a discrete (finite) change in lift coefficient $\Delta C_{L_{gust}...
- 15.6k
3
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How are individual spool optimal speeds determined in 3-spool engines like Trent 700/800?
The most determinant factor is air pressure varies along the compressor stages, and along the turbine stages. This requires adjusting the air duct cross-section, and in turn the blade size, which ...
- 77k
4
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Why do commercial jets fly so high?
I think that historical perspective is the easiest way to understand why flying higher was needed in the first place (other than efficiency as requested in the question).
The first commercial airliner ...
- 14.7k
7
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Why do commercial jets fly so high?
The most important reason for commercial aircraft to fly high is fuel efficiency.
The thrust specific fuel consumption (TSFC) of jet engines scales with the square root of the temperature. Colder air ...
- 15.6k
15
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Why do commercial jets fly so high?
One of the main reasons to fly high has nothing to do with efficiency and everything with passenger comfort: flying above the weather. The majority of weather phenomena, especially turbulence, happens ...
- 13.7k
9
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Why do commercial jets fly so high?
Yes there is another reason. During the cruise phase of the flight the aeroplane burns fuel and its weight reduces, and its lift must therefore reduce as well to maintain equilibrium. So should it now:...
- 62.3k
0
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How do I place wings on a fuselage for testing?
Method A and Method B are obviously going to give different results. Method C could be when the wings join below the fuselage and method D when the wings join above the fuselage.
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- 1,210
1
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Accepted
How do I place wings on a fuselage for testing?
The conventional way to measure wing area includes the projected vertical area of the fuselage segment between them, either by spanwise line segments or by extending the leading and trailing edges (...
- 12.6k
2
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What's the airplane with the smallest ratio of wingspan to fuselage width?
Maybe not a winner, but a not-to-be-missed aircraft nonetheless, the Gee Bee Model R Super Sportster
Image source
With a wing span of 7.62 m and a fuselage width of 1.98 m, it ends up with a ratio of ...
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12
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Which aircraft has the simplest folding wing mechanism?
There are many planes with folding wing structures. Some like the F/A-18 fold a small part of the overall wing and similar is with the 777X
From what I got to know, the aircraft with the simplest ...
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5
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What's the airplane with the smallest ratio of wingspan to fuselage width?
You might consider the 1955 Pritchard Rocket Air Ship, (which was neither a rocket nor an airship) with the major caveat that it never actually got off the ground.
source
source
Charles Pritchard, ...
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