Questions tagged [sideslip]
A flight condition where an aircraft's direction of motion is not aligned with its longitudinal axis, causing the aircraft to "slip" sideways through the air.
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Airspeed indication in a forward slip C172?
I have read several topics on the manner with two completely different answers, and just want to make sure I get it right.
When slipping to the right in a C172 (right aileron, left rudder), the static ...
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Simultaneous yaw damping and sideslip control of aircraft with rudder?
Yaw damping is achieved by using the rudder to generate a yawing moment that opposes any yawing motion. Also, rudder is used to correct sideslip by applying a rudder input in the opposite direction of ...
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In a plane with airbrakes, such as a glider, how do slips and airbrakes interact?
While adding a slip to enhance my descent rate, I got to thinking that the airbrakes might be losing effectiveness as the slip twists them out of the relative wind. This thought arose because I did ...
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Actual non-axial airflow (sideslip) for a propeller driven aircraft
I am making a propeller model for a two-engine propeller driven aircraft (like a Dornier 228). I have expanded my model to include the non-axial airflow as well. $$ $$
By non axial airflow, I mean ...
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Forward Slip - Which speed to maintain?
Which is the proper speed to be maintained during a Forward Slip? Near Vfe or Vref? Which one will let you lower with the shorter ground distance and why?
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Y force of airplane in ground effect
How can I get the y force of an airplane in ground effect when using image theory? is the y force zero because of the mirror cancelling it out? bare in mind I'm talking about a case where there is a ...
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How does conical camber decrease roll due to sideslip?
I was reading Ray Whitford's Design for Air combat and came upon a passage that said that on the SR-71 conical camber "gives a useful reduction in the otherwise very high rolling moment due to ...
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Would twin-engine airplanes be safer (in case of engine failure) if had minimal dihedral?
In the specific context of the sudden failure of one engine, would twin-engine airplanes (with wing-mounted engines) be safer if designed with minimal dihedral, so that aerodynamic coupling between ...
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Am I slipping or am I skidding?
I'm in a shallow left bank, maybe 15 degrees. Right rudder pedal is all the way to the floor. Flight path is curving toward the right. Ball is far to the left corner of the glass tube. Yaw string1, ...
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What causes a slip/skid turn? [duplicate]
Is the rate of turn being too low/high for a given bank angle the cause of slip/skid turn? Or is it yawing too much inside/outside turn causing an imbalance in centripetal/fugal force and thus the ...
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Causes of yaw in slip/skid turn [closed]
Why does the plane yaw when the rate of turn is not suitable to bank angle in a turn? In a slipping/skidding turn, there is an imbalance of centripetal/ centrifugal force. How does that cause a yaw?
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Lateral Aerodynamic Derivatives from Digital DATCOM
As far as I know the Digital DATCOM can be used to estimate longitudinal aerodynamics by varying the angle of attack. Does it have the capability to vary sideslip angle for lateral analysis? and How? ...
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Calculate/Measure Sideslip Angle from Heading Track and Drift Angle
Is there a way to measure the sideslip angle during flight through the relationship of heading, track and drift angle? For example if you turn the aircraft into head or tailwind - does the sideslip ...
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Do aircraft pitch down even at very low angles of attack (below 0°) in a strong sideslip?
I was doing an analysis of an aircraft (specifically the PZL Koliber 160 with the NACA 63A416) strong sideslip conditions (beta=30° for example) in OpenVSP at various angles of attack, and observed ...
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What is a rough estimate for a sideslip angle for a Dutch Roll?
I previously asked: Is there a regulatory maximum side slip angle for commercial aircraft?
Apart from a regulatory maximum, can anyone give me a rough value to assume for sideslip angle during a dutch ...
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Is there a regulatory maximum side slip angle for commercial aircraft?
Hi am currently trying to run Dutch roll simulations for a proposed 35 seat twin engine turboprop aircraft.
I was just trying to work out what sideslip angle might be appropriate to use. Is there a ...
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What happens to Lift and Drag on aircraft (and its components) when sideslip is increased gradually from 0 degrees to 90 degrees?
I possess an Aerospace Engineering background, and work as a Aerospace structural analyst at a local firm. A portion of my job is dedicated to determining the critical conditions that the aircraft and ...
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Viable to slip onto the center line?
One of the constant problems of aviation is drawing onto the center line on final. Either due to a bad rollout or due to crosswinds a pilot often finds that the aircraft is not on the center line for ...
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Forward slip dynamics
I am perplexed on the dynamics of the forward slip. I am illustrating here:
The intended ground flight path is axis +y, and the plane is forward slipping by banking right + left rudder.
In order to ...
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Do redundant angle of attack and sideslip sensors use a voting mechanism, or do they display data directly?
In civil transport aircrafts (featured with dual/triple redundancy), how does airplane's Airflow angle (AoA/AoSS) sensor measurements read by the pilot? By using voter mechanism as used for airspeeds ...
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Why do flying wires hum louder in a sideslip?
Page 50 of the Feb. 2021 issue of the EAA's magazine Sport Aviation reports that
Like any good vintage airplane, the Sea Bird likes to fly coordinated,
and the flying wires will sing out loud if the
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What causes the ball to not be centered in a slip/skid?
I've reviewed quite a few questions on this forum including
Forces in a slipping turn
is-this-vector-diagram-of-the-forces-at-play-in-turning-flight-correct
what-does-the-balance-ball-actually-...
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Does the routine flown by the Thunderbirds in the F-16 feature true sustained knife-edge flight?
Does any aerobatic routine flown by the USAF Thunderbirds in the F-16 feature true sustained knife-edge flight?
By "true sustained knife edge flight" we mean that the aircraft is maintaining ...
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Is drift and sideslip angle the same in the accompanied figure?
Consider the following figure:
Initially aircraft is moving along dotted line. But due to wind, aircraft ground track is changed to solid line but body still pointing parallel to dotted line. I've ...
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In a full-rudder sideslip in a Schweizer 2-22 or 2-33 glider, is the descent rate higher at 50 mph airspeed than at 60 mph airspeed?
Is it really true that in a full-rudder sideslip in a Schweizer 2-22 or 2-33 glider, the descent rate is higher at 50 mph airspeed than at 60 mph airspeed?
Likewise, is it really true that in a full-...
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Why is there a a nose-up pitching tendency during a forward slip in a Cessna 172?
Why is there a tendency for the nose to pitch-up during a forward slip in a Cessna 172 (According to the TC Flight training manual)?
Quote:
"If full rudder is used, considerable aileron pressure ...
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Why does a steady-state non-zero body yaw and/ or roll rate induce side force?
An answer on ASE states
The presence of steady-state non-zero body yaw and roll rate induces side force ($C_{y_p}$ and $C_{y_r}$).
What is a non-mathematical explanation of why this is so?
Is it ...
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Why does a banked aircraft create sideslip?
Below is an excerpt from Raymer (Aircraft Design) where he explains the dihedral effect. He states that a banked aircraft (due to say a roll disturbance) will have a sideslip which leads to a ...
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How are coefficients of equation of sideslip angle in the paper "A general Solution to the Aircraft Trim Problem" calculated?
I am sure many of you guys must have read the paper, "A General solution to the Aircraft Trim Problem" by Marco, Duke and Bernt. I am working with the turning of the Aircraft and I am not able to ...
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Mushing glide vs forward slip sink rate
Source: Wolfgang Langewiesche - Stick and Rudder; An Explanation of the Art of Flying
I ran across a mushing glide in Wolfgang Langewiesche's - Stick and Rudder; An Explanation of the Art of Flying ...
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Why should one not slip a Cessna 172 with flaps extended?
The POH strongly recommends not slipping the AC with full flaps...why?
It seems natural in a crosswind approach to
allow the horizontal lift component to cancel the airmass movement across the ...
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Forces in a slipping turn [duplicate]
I have trouble understanding why the ball (on the turn & slip indicator) falls into the turn e.g. drop to the left when aircraft is rolled left, when in an uncoordinated turn (slipping turn). What ...
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What is missing from these diagrams of the forces in slips and skids?
See these images that are widely reproduced in many different on-line ground school materials.
A) Is the magnitude of the wing's lift vector illustrated correctly in each of the three cases? Should ...
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What does the balance ball actually indicate?
Given answers and comments from a previous question, I realize that I need to clarify what the ball actually measure. I think it does not measure side slip but sideways acceleration, but I'm not quite ...
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How does sideslip indicator react during crosswind?
I will basically consider two types of sideslip indicator: the yaw string and the marble/ball inside a curved tube. I don't know the exact aeronautical term for both and I don't know if other sideslip ...
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Is it possible to calculate lateral acceleration from pitch/yaw/roll rates?
Can you calculate an aircraft's lateral acceleration from the aircraft's yaw, pitch and roll rates? If so, how?
This is to implement a digital slip indicator.
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Finding Angle of Attack/Angle of Sideslip using East/North/Up Coordinates
I've got a set of data that includes:
x rate, y rate, z rate (all ENU) which I'll call xd, yd, zd.
roll, pitch, yaw (which I'll call ϕ, θ, ψ)
roll rates, pitch rates, yaw rates
I'm looking at some ...
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Why does a turn and slip indicator matter?
I'm studying the principles of flight, and I'm having some unanswered questions in my mind regarding the turn and slip indicator.
I'm reading that a turn and slip indicator displays the slip or skid ...
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Is a high alpha sideslip possible and safe?
Is a high alpha sideslip possible and safe?
We use a sideslip to increase drag when trying to reduce altitude before landing on a short runway, etc., which is crossing your rudder and ailerons, to ...
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At what angle-of-attack (sideslip angle) would a symmetric vertical fin plus a deflected rudder have a lift coefficient of exactly zero?
For rudder deflection angles of 5, 10, 20, 30, and 45 degrees, at what (negative) angle-of-attack does a fin-rudder combination (including dorsal fin if present) have a lift coefficient of exactly ...
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Sideslip vs Freestream Azimuth Angle
Why is the sideslip angle, $\beta$, defined as
$$\beta=sin^{-1}\left(\frac{v}{|{\bf v}|} \right)$$
and not the same as freestream azimuth angle $\psi$
$$\psi=tan^{-1}\left(\frac{v}{u} \right)$$
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Why does elevator input move the turn coordinator ball in steep turns?
When practicing steep turns, I'm running into an unusual phenomenon. If the airplane is losing altitude in coordinated flight and I apply aft stick pressure to pitch up and correct, I notice that the ...
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Which way (if at all) do the ailerons need to be deflected in a full-rudder sideslip in a Cessna 152 or 172?
Do you typically have to maintain an aileron deflection in a constant-heading full-rudder sideslip in a Cessna 152 or 172? If so, in which direction? And why -- what is the source of the roll torque ...
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In which direction will an aircraft drift after taking off in a crosswind?
Assuming the pilot applies the appropriate crosswind flight controls (see below) during takeoff and rotation, and releases those flight controls after the aircraft leaves the ground, in what direction ...
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How can using split throttles help when landing twins in crosswinds?
In General Aviation light twins, when landing in heavy crosswinds, what are some considerations to using asymmetric (or Split) throttles to induce a sideslip, to align the fuselage with the ground ...
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Is there a specific relation between sideslip angle and yaw rate OR how sideslip angle depend on yaw rate?
Since, yaw rate is controlled via rudder and sideslip angle can also be controlled by rudder, I want to know if there is any dependence of sideslip angle on yaw rate in fly by wire aircraft as I am ...
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Is it dangerous to do a skidding turn to lose altitude without increasing airspeed?
I was taking some lessons in a light sport aircraft in South Africa a few years back, my instructor taught me something which I had never seen or heard of before or since. We went through an emergency ...
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How is a sideslip maintained (aerodynamically)?
(Public domain image that I've modified.)
The initial rudder deflection to the left creates a side force that points right and yaws the plane to the left.
NASA puts it this way:
For the vertical ...
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How do uncoordinated turns (skid, slip) affect a helicopter's turn radius?
Is a helicopter's flight path (track made good) an arc of constant radius regardless if it's a coordinated or uncoordinated turn? (Assume nil wind conditions and that the pilot maintains the angle of ...
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What is the relationship between the UH60 Blackhawk stabilator function lateral sideslip and pitch coupling?
I'm having a hard time understanding the correlation between the wind gusts (where are they coming from, what are they affecting) and why, in a nose left situation, the stabilator is driven down.
I ...
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