Skip to main content

Questions tagged [aircraft-physics]

Physics as they apply to aircraft. Including aerodynamics, flight dynamics, stability and control, aircraft hydraulic and electric systems, engine thermodynamics.

Filter by
Sorted by
Tagged with
0 votes
0 answers
39 views

induced drag at supersonic speed [duplicate]

for a delta wing with supersonic leading edge at small angle of attack there is no stagnation point on leading edge so There is no connection between the top and bottom of the wing. Therefore, the air ...
alireza's user avatar
  • 113
4 votes
4 answers
266 views

In a hot air balloon what proportion of the lift comes from the heated air compared to that from the combustion products?

A hot air balloon is heated with propane or similar hydrocarbon. One of the products of combustion is H2O with molar mass 18 so it is substantially less dense than air (78% nitrogen, molar mass 28 and ...
Ken Mercer's user avatar
0 votes
0 answers
34 views

Does partial flow separation due to toggle input affect the physics of paraglider/ canopy controls?

A skydiving canopy designer said the following: Airflow is separated even before stall on a big portion of the canopy.... It's specific to [the] way toggle[s] distort the trailing edge. Is this true,...
Oleg Pryadko's user avatar
2 votes
0 answers
41 views

How does ground effect work with a banked wing?

How would an explanation of ground effect such as this one from Peter Kämpf be modified to account for a highly banked wing? A paraglider and HP canopy pilot told me that when he banks a wing to touch ...
Oleg Pryadko's user avatar
1 vote
0 answers
42 views

Does ground effect affect a paraglider/ canopy?

I've heard that ground effect is only significant if the wing is closer to the ground than its span, and I've never seen a canopy/ paraglider that would qualify for that. Is that true or would there ...
Oleg Pryadko's user avatar
3 votes
0 answers
71 views

Is the thrust/lift trade-off for powered lift linear?

On the wikipedia page Powered lift there is this graph of thrust vs lift: (public domain) This graph shows a roughly constant (not exactly constant but that's not the point) sum of thrust and lift. ...
user avatar
0 votes
2 answers
124 views

How to maximize L/D ratio by design in a high altitude glider? [closed]

EDIT: Some initial confusion with TAS and IAS confused me, I now understand this better, thanks for everyone who helped. I'm designing a high-altitude glider, and I'm wondering how the angle of attack ...
Charles Nicholson's user avatar
2 votes
0 answers
82 views

Doubt in the Coriolis component of the net force acting on the aircraft

I dig a little and got to know that the force equation in 6DOF are nothing but a mathematical depiction of the fact that for a translating & Rotating body in 3D,The net force is the Translational ...
Ravi Pratap Singh.'s user avatar
1 vote
0 answers
24 views

Intersecting Boundary Layers in XFLR5

I am analyzing an airfoil called RevE-HC. While doing a type-1 analysis, I encountered that the BL is intersecting towards the trailing edge. The panels are refined and the geometry is also smooth. ...
Hellbat's user avatar
  • 11
23 votes
1 answer
3k views

Does a carbon fiber fuselage suffer wear from pressurization/depressurization?

I've heard many times that one of the factors that causes wear and tear to the fuselage of airliners is the pressurization and depressurization from each flight. From what I recall these were ...
Gabe's user avatar
  • 3,217
3 votes
4 answers
576 views

What are the correct Cd0 and Cdi values for a NACA 2412 airfoil?

According to an answer to this question, at best L/D the the drag coefficient is evenly split between Cd0 and Cdi. I'm going to limit the question to the Cessna 172 and its NACA 2412 wing with an ...
Robert DiGiovanni's user avatar
0 votes
2 answers
195 views

why does the rotor could head (Nr) "overspeed" if the collective is lowered suddenly, what is the Physics behind it

I know that in helicopters the N2 and Nr are coupled. I would appreciate a physical explanation leading to the cause of how the rotor blades could overspeed if collective (power) is lowered suddenly I ...
YamchaAviator's user avatar
2 votes
4 answers
400 views

Would it be practical to have missiles that can aim forward and backwards?

I have been researching recent air-to-air combat kills in some recent wars and in every case it seemed that the pilot who was in the back won. So I was wondering why they don't just design a missile ...
Jordan Stephan's user avatar
2 votes
1 answer
147 views

What's the efficiency between the duct and the fan blade?

I've heard many times that the smaller the gap between the fan blade and the duct, the better the efficiency/thrust is. Is there a formula or graph available to see how much efficiency is lost as you ...
Gabe's user avatar
  • 3,217
1 vote
1 answer
189 views

Could an passenger jet perform a complete power down & up IN FLIGHT? [duplicate]

I've read various references that it is not uncommon that modern passenger jets' computer systems need an occasional reboot to fix some erratic state. Of course, that is done on the ground and ...
ManoG1234609's user avatar
12 votes
2 answers
5k views

If a Cessna 172 is dropped from the sky, what minimum altitude is needed to safely land?

If an aircraft like a Cessna 172 is dropped from a helicopter, what absolute minimum altitude above the ground will be required to safely land the aircraft? CONDITIONS: Weather: Perfect conditions, ...
Gabe's user avatar
  • 3,217
0 votes
0 answers
65 views

Gyroscopic Precession in Coaxial Helicopters

I'm trying to understand gyroscopic Precession in the case of coaxial helicopters. Obviously the effect still exists. But if gyroscopic Precession is a result of counter torque. Shouldn't the effect ...
Slartibartfast's user avatar
1 vote
1 answer
555 views

What causes magnetic compass turning errors?

What exactly causes magnetic compass turning errors? I found two completely different and contrasting explanations online and I'm confused as to which one is correct. Explanation 1: Reference: ...
Katrina's user avatar
  • 35
2 votes
2 answers
351 views

What causes magnetic compass acceleration errors?

I was trying to find out what exactly causes magnetic compass acceleration errors, and I found two completely different and contrasting explanations online (both are supported by an equal amount of ...
Katrina's user avatar
  • 35
0 votes
0 answers
115 views

How do you calculate the theoretical vertical speed of an aircraft? [duplicate]

I'm doing this for a High School research paper, so it would be preferable if little calculus is used for any calculations (up to Calculus I is probably okay). This should be based off of the flight ...
Joe Dahl's user avatar
0 votes
1 answer
162 views

Does the “Torque-Induced Precession” of the two rotor blades cause the V-22 Osprey to tear itself apart

Concerning Bell Boeing V-22 Osprey Aircraft: Does the “Torque-Induced Precession” of the two rotor -- 3-blade, propellers cause the V-22 Osprey to become unstable. In the case of a helicopter the ...
Symmetry's user avatar
0 votes
0 answers
43 views

What is the speed and temperature profile of the boundary layer at the stagnation point?

At the statgnation point where the air velocity is zero, what is the shape of the velocity and temperature profile of the boundary layer? Is the velocity profile of the boundary layer in the form of a ...
alireza's user avatar
  • 113
1 vote
1 answer
154 views

Exhaust temperature of CFM56 engines range (Nozzle downstream temp)?

EGT is available but not the temp of the exhaust nozzle in the CFM56 series.
Setare's user avatar
  • 13
12 votes
5 answers
4k views

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 ...
Lycodo's user avatar
  • 123
0 votes
1 answer
131 views

Yawing during turns

This is a question about aeronautics. Does an airplane yaw while it is turning?
BomberJoe's user avatar
0 votes
0 answers
161 views

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 ...
Nathan Zhou's user avatar
0 votes
0 answers
95 views

Deriving Accurate Exit air velocity of rotor

My goal is to derive the equation for exit air velocity as a function of: Pitch angle RPM Rotor Radius Constants like ρ Assumptions: Vc is relative velocity of air upstream, and is = 0 Inflow is ...
Luke-McDevitt's user avatar
0 votes
0 answers
30 views

Is the Lift required for a steady-state climb and descent equal for the same absolute value of the kinematic climb angle? [duplicate]

Here is my confusion : I found in my lecture script the following equation for the steady-state climb and descent (wings level) ...
Christian Mändle's user avatar
1 vote
1 answer
199 views

Is the Reference Speed (Vref) the same as the speed at which the aircraft cross the runway threshold in landing phase?

Just a little confuse when I learned about the aircraft classification based on approach speed. Can anyone help me to have an accuracy look about this question?
Harry Huynh's user avatar
0 votes
1 answer
210 views

Does pilot need to increase thrust when gust hit him at landing and where is axis of rotation?

Let's say a plane is flying above a runway in straight line, and gust of wind hits the plane from side. Do pilot need increase thrust to stay above runway and where is axis of rotation ? It often said ...
user707264's user avatar
  • 1,958
11 votes
5 answers
4k views

Do airliners respond to mild turbulence in real time?

I've always been fascinated with the impact of ailerons on an aircraft's trajectory; from what I have seen sitting by a wing is that the slightest movement can bank the aircraft quite significantly. ...
roganjosh's user avatar
  • 213
9 votes
5 answers
3k views

Why do newer engines have such wide fan blades?

Every treatise I read about propellers/fan blades/wings states that long, thin wings are more efficient than wide stubby ones. So why is it that the blades in high-bypass turbofan engines fitted to ...
Buk's user avatar
  • 93
8 votes
3 answers
5k views

Flying upside down without feeling it

A friend of mine told me that several years ago she flew on a two-seats general aviation aircraft. She does not remember the exact model, but she remembers well that the pilot flew upside down for a ...
Mark's user avatar
  • 293
5 votes
2 answers
1k views

Do fuel tanks need to be pressurized?

Do fuel tanks need to be pressurized? It's my understanding that the pressure difference between the outside air and the inside fuel would force the kerosene out of the fuel tank. What stops this from ...
Mateo's user avatar
  • 746
1 vote
1 answer
201 views

How does elevator control effectiveness change with altitude/ air density?

Suppose an unpowered, rigid, mechanical, lightweight aircraft (e.g. sport glider) is descending at a steady glide in a constant trim (hands off) configuration in a standard atmosphere. The pilot ...
Oleg Pryadko's user avatar
1 vote
2 answers
140 views

Why will all air slow down by the same amount in an adverse pressure gradient?

Boundary layer separation is caused by air slowing down to zero and reversing before reaching the end of the body. This is due to friction (viscous effects) + adverse pressure gradient. The formation ...
Frank's user avatar
  • 415
5 votes
3 answers
912 views

How does momentum thrust mechanically act on combustion chambers and nozzles in a jet propulsion?

I'm asking this question since I can't intuitively understand how the acceleration of mass flow and therefore the increase of its momentum can actually mechanically act on the combustion chamber ...
MK.s's user avatar
  • 65
1 vote
1 answer
208 views

Why does bank angle have no effect on pivotal altitude?

Pivotal altitude is the height for a given ground speed at which the line of sight from the cockpit directly parallel to the lateral axis of the aircraft will remain stationary on an object on the ...
astroball's user avatar
0 votes
1 answer
260 views

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, ...
Frank's user avatar
  • 415
1 vote
1 answer
185 views

What are the flight formulas for aircraft

I am making a 2D flight "simulator" (trying to be as realistic as you can for 2d) and I need flight formulas for lift, speed and pitch. I have tried a few sites but I do not understand what ...
wvzack's user avatar
  • 13
2 votes
0 answers
69 views

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 ...
Martin Moreno Vega's user avatar
2 votes
0 answers
182 views

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 ...
Dwight Schrute's user avatar
2 votes
1 answer
77 views

How can the effect of wind gradient in a glide be calculated?

If an airplane glides in a mass of air where the headwind changes with altitude, it seems logical to think that the length of the glide –as measured by a ground-based observer– will be longer in the ...
xxavier's user avatar
  • 11.1k
3 votes
1 answer
137 views

Energy Maneuverability Theory Applied to WW1 Fighters

I am trying to test the Fokker D.VII, Spad S.XIII, Sopwith Camel, Nieuport 28, and the Se5a using the model in this paper: https://apps.dtic.mil/sti/pdfs/ADA066034.pdf It's called Combat Performance ...
MathFareswell's user avatar
0 votes
2 answers
566 views

How does a zero g aircraft work?

In upward motion, drag and gravity is in the same direction (both in downward direction). So in this situation G is negative or less than 1 or something else? In downward motion with thrust greater ...
alireza's user avatar
  • 113
0 votes
1 answer
269 views

Lateral location of the center of pressure

I am working on a simple flight simulator. For this, I need to calculate aerodynamic forces and apply them to the aircraft. As I understand it, lift and drag act through the wings center of pressure. ...
gue-ni's user avatar
  • 3
2 votes
2 answers
727 views

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 ...
shrey's user avatar
  • 21
0 votes
4 answers
2k views

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 ...
Latex User 101's user avatar
0 votes
1 answer
188 views

Cruising at the speed of sound

Is it possible or feasible for an aircraft to continuously cruise at the speed of sound? Is the drag at this point higher or lower than in the high Mach 0.98 or Mach 1-1.2 region?
user67740's user avatar
  • 279
4 votes
1 answer
234 views

aerodynamic forces on an engine cowling

In Mendenhall's book about the Gee Bee racers, he describes that on the Models Z, R-1, and R-2, there was a strong tendency for the engine cowl to get pulled forward and into the prop during races, ...
niels nielsen's user avatar

1
2 3 4 5
9