Questions tagged [aircraft-structures]
For structural engineering questions about airframes and the mechanical structures aboard aircraft
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What is the purpose of a wing Yehudi? [duplicate]
Apart from covering the landing gear leg, the Yehudi also increases the wing root cord which allows the build height for the root to increase for the same wing relative thickness. This is useful as ...
user14897
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3
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How are engines mounted onto wings?
I've heard that the engines on a commercial air transports are typically mounted with 2 or 3 bolts. Is this true? If so, how big are these bolts and what are they made of?
I'm optimizing a bolted ...
- 1,058
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What is the definition of load factor and how do you apply it?
I'm a little confused about the definition of the load factor, n, as the definitions I found seem to contradict its application in force and moment balance analysis of an aircraft structure.
The ...
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How come planes can endure more positive than negative g's? I.e. how come V-n diagrams are not symmetric?
In this question A380 reverse thrust on only half the engines some doubts were raised about the strength of structures in certain directions.
Specifically, Peter Kämpf states:
Aluminium and ...
- 7,157
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What is the average weight difference between composite and metal airliners?
Is there any rule of thumb for weight savings using composite materials. For example, is there an early model large airliner like the B747 or even B737 that later was modified with composite wings or ...
- 11.5k
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Why are modern aircraft wings often pointed instead being more rectangular?
When viewed from the Z axis (above or below), why are modern aircraft wings often pointed as they get towards the wingtips instead of maintaining the same surface area for their entire length?
This ...
- 2,229
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What physical tests are involved with verifying a wing spar is suitably constructed for a homebuilt aircraft, such as the piper cub kit from wicks?
During construction how is a spar tested to ensure it can adequately cope with bending and twisting forces of the completed structure, or is this performed after complete?
- 737
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Could winds of up to 150 km/h impact the structural loads on a Boeing 777?
From 15 October 2016, AI 173 from Delhi to San Francisco started flying over Pacific. Jet streams over Pacific helped Air India in reducing the flight time by 2 hours, despite increasing the travel ...
- 11.5k
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What is the aerodynamic purpose of an Acorn?
This is an IL-62. On the tail of the aircraft, there is a large cone, protruding out of the vertical and horizontal stabilizer which is called acorn. I am trying to figure out what is the aerodynamic ...
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Is pilot alerted of any physical or structural failures?
Current crew alerting system messages, I believe, are displayed basing on the software detection of the failures basing on the sensor information.
What kind of structural failures can occur to an ...
- 2,359
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Why don't aircraft (commercial and military) use reflective visor windshields?
Just like those used on an astronaut's helmet, these reflective visors can help in better visibility when facing the sun (or any bright light source). But the windshields of most aircraft (commercial ...
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Why are empty pylons weighed down?
(airplane-pictures.net) Airbus A330 no engine option.
Why are empty pylons weighed down?
The plausible answer is to maintain the correct center of gravity. But why not just load ballast pallets in ...
user14897
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Why do T- tail airplanes have a shorter vertical stabilizer?
Airplanes with a T-tail design have a shorter vertical stabilizer than the conventional design , what is the reason?
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What are the tube shaped structures on the back of the fuselage of this 737?
A previous question asked what the little metal plates between the horizontal and vertical stabilizer were (they are vortex generators), however I am much more interested in what the gray tube shaped ...
- 54k
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Are modern airliners still stressed-skin aircraft?
Can modern airliners still be seen as stressed-skin aircraft?
i.e. is the skin, whether it be aluminium or composites, still an integral structural member of the airplane?
- 2,038
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Why do airliners have "pressure bulkheads"?
Image source: FAA
What part of the fuselage aft of the bulkhead would leak pressure? Or is it just there to reduce stresses?
How does a DC-9/MD-80/90 incorporate aft bulkheads when there's a ...
user14897
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2
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Are lockwires still preferred over self-locking nuts and other ways of bolted joints` safety?
I've watched some of the lockwiring videos and if I understood it right then there are two most widely used ways of ensuring that a bolted joint does not get loose:
Lockwire
Self-locking nuts
...
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How are folding wings managed?
There exist several aircraft - especially carrier-based ones - that have folding wings, to save space.
How is this structure strong, taking into account the considerable amount of force on the hinge-...
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What is the difference between a wing station and wing buttock line?
Can someone explain (with images) what the difference between a Wing Station and Wing Buttock Line is, in terms of aircraft structures location identification?
The text I'm reading states:
W. STA ...
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Can delamination be detected early?
When a composite structure is hit, the impact causes shockwaves which travel through the structure, and cause delamination. Delamination reduces the strength of the composite structure and may cause ...
- 2,446
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Is all the extra lift from flaps added upstream where the spars sit?
Flaps can significantly increase the lift for a wing, is all that extra lift added upstream where the spars sit? I ask this question because the flaps in airliners seem to be only connected by a few ...
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How much lift does the wing attach fitting actually carry?
How do I calculate the lift force that the the bolt that join the wings to the fuselage of a strutted or braced airplane carry?
I know in a cantilever airplane,the bolts have to carry all of the lift ...
- 2,885
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What is the function of interplane strut of a Biplane?
What kind of load does the interplane strut(s) carry,is it compression, tension or shear?
In order words,what's their function and how do you calculate the force that the interplane strut carries?
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Why is the wing bending so much in this video? [duplicate]
On a recent vlog, YouTuber CGP Grey mentioned how much the wing of the plane he was on bent. I understand that wings are designed to bend a little, but what actually causes so much deformation?
...
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How to identify load paths? [closed]
How would you go on about identifying the load paths on an empennage structure, wing and fuselage?
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How can one calculate the maximum instantaneous bank angle a plane can do in a certain time? [duplicate]
I know that there is a limitation to do an instantaneous banking angle a plane can do. These limitations are due to the airplane (infrastructure - aerodynamics) and limitation on the pilot (due to his ...
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