Questions tagged [flight-controls]
Use for cockpit controls (trim, yoke, etc). Use [control-surfaces] for the surfaces that actually move.
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How to fold or expand the wingtips on Boeing 777?
I have heard that some Boeing 777's wingtips can be folded when the aircraft is on ground. However, I didn't find the switch to control the wingtips. Where are these switches?
Btw, I use FlightGear ...
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Tiller use on takeoff
When a commercial jet aircraft has been cleared for takeoff, does the PF use the tiller for steering, up to a certain speed? I've seen many vids where it seems the PF uses the yoke/sidestick for ...
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Trimming direction on climb out and descent to maintain an airspeed
What direction do I trim in order to catch an airspeed with the control stick while on the approach in the circuit pattern? When I normally trim out the control pressures while in the region of normal ...
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References for lift and drag coeficient formula/values
I'm looking for references for values/formula for lift and drag coenficients. In this paper https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6244461 it is said that
$C_L(α)$ and $C_D(α)$ ...
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Missing position (lat/lon) in ADSB data
I would like to ask if anyone has encountered latitude longitude (Data Item 021/130) missing in ADSB data, specifically in asterix cat 21. In addition to the mandador entries, there is also geometric ...
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In a straight and level flight if thrust is equal to drag how is aircraft moving forward?
If two forces are equal and acting in opposite direction should not the object remain stationary.
Is there an excess thrust which actually pushes the aircraft forward ?
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Has the inceptor (control stick) ever been controlled via using CAN bus control?
The CAN bus is being used widely in the automotive industry, and some aircraft are using the CAN bus control.
Is there any inceptor (control stick) or throttle that can be connected to the CAN?
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Whats the derivation of a low speed ratio for stall warning?
I've seen an equation related to stall and angle of attack in a few places like this patent that goes more or less:
$$ \frac{CAS_{alert}}{CAS_{current}} = \sqrt{\frac{C_{L,current}}{C_{L,alert}}} $$
...
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Can we use leaf shutter mechanism as a drone dropping mechansim for payload weight of 3lbs?
I'm considering implementing a drone payload drop mechanism capable of handling payloads weighing up to 3lbs. I'm intrigued by the idea of using a leaf shutter mechanism for this purpose, but I haven'...
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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 ...
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Elevator / horizontal tail effectiveness at high speeds?
Take for example a jet fighter, when at low speeds vs high speeds, airspeed will differ a lot. As the turning moment is due to the lift force from the tail and lift increases quadratically with ...
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What does the C* (Cstar) parameter demand ?(A320)
I have been reading a LOT of research papers and many articles, but none of them tell how the C* parameter in Airbus is used for the vertical augmentation of the aircraft.
I am aware that with a ...
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What happens to ADIRU/FAC AP etc, when Pitot probes fail?
Situation: Suppose due to a bird strike pitot 1 is blocked with debris and radome is dented causing inconsistent airspeed indication between P2 and P3 (due to unequal airflow). This happens at about ...
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How can I control the flight path angle (or the ROC) with throttle in Simulink?
I need to implement an autopilot for my 3DoF (longitudinal motion) aircraft model in Simulink. My model is nonlinear, but linearizing it in Simulink hasn’t been an issue.
I’m trying to develop a ...
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why stabilator has a lower travel limit for down movements?
Within the POH of my aircraft, in a part titled "Control Surfaces Travel Limits", the manufacturer states:
Stabilator: Up 18° --- Down 3°
Why stabilator has a lower travel limit for ...
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How was the 747 and DC-10's trimmable stabilizer actuated?
I was recently reading about Alaska Airlines Flight 261, a crash where understanding it in detail requires a bit of a deep dive into the trimmable stabilizer. On that particular aircraft (MD-80), it ...
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How to develop motion model for RC plane
I'm interested in controlling an RC plane autonomously, and to do that I need a basic motion model.
How would I do this? Particularly without a wind tunnel?
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Questions with A220 control logics
I'm gonna take simulator check for new-hired co-pilots.
The company will do simulator test in A220 for new-hired copilots. Their applicants have no experience in jets, have experiences only in single ...
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Hexacopter Vn diagram/ flight envelope/ operational envelope
I am currently intern at a company. They are making agriculture hexacopter, now there is a confusion that does the hexacopter or multicopter have a V n diagram if yes how to make one what's the ...
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Can a person with cerebral palsy become a pilot?
I have mostly succeeded at everything I want in life except the one hobby I wish I could take up, and of course that hobby is flying, or I wouldn't be asking here.
Background
I graduated high school ...
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Approach miniumum when I lost WAAS during approach
I have a GPS receiver with WAAS.
During an LPV approach, I received an LOI message
That means I only lost WAAS, not RAIM.
Did I just need to change minimum to LNAV and continue the approach?
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What are the "Aft Bobweights" for on a full power hydraulic aircraft?
I like military aircraft, and recently I've been researching the feel system for the control stick.
It seems that there is something called bob weights to improve the feel of an aircraft. It's a ...
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After designing an autopilot, how does it affect aircraft modes?
Let's say an autopilot will be designed for the longitudinal axis. A pitch attitude hold will be made with a sas in the inner loop and a pid in the outer loop. How does this system change the phugoid ...
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A transfer function relating jet engine thrust to pitch angle during a phugoid motion
Crossposted on Mathematics SE
I am doing a school project that requires me to find a transfer function that relates the thrust of a jet engine (which could change with time in one way or another) and ...
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What's the more accepted notation used to label sensors present in turbo-jet engines?
I'm interested in learning what the proper (more accepted) notation used to label sensors present in turbo-jet engines is.
Came across a few examples such the ones shown below but would like to learn ...
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Why is it that when autopilot is maintaining cruise, we don’t feel the changes when lift increases?
When we’re inside an aeroplane, when we’re in cruise, why is it that we don’t feel the changes in altitude, lift and the adjustments for example from the elevator on the plane as the weight is burned ...
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How exactly is cruise maintained as fuel is burnt?
Can someone please explain how exactly cruise (I think it’s called straight, level and un-accelerated flight) is maintained for like an airliner please?
I’ve read a few answers on this website for ...
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What type of ailerons does the Piper Seminole has?
I understand that the PA44 has differential type ailerons, but do they also have frise type ailerons? Making them a combination of differential and frise type similar to the Cessna 150/152/172 models?
...
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Why is a flat turn less efficient than a coordinated turn?
How I understand a flat (rudder-only) turn:
AOA between relative wind and the fuselage of the airplane causes a sideslip in the direction of yaw.
Vertical stabilizer weathervanes into the relative ...
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Human error analysis in general aviation [closed]
can anybody help me with understanding more about the human factors analysis in general aviation Controlled flight into terrain. I am researching on the topic and I would really appreciate any help in ...
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What are the key differentiating factors between the flight control systems employed in unmanned drones and those utilized in piloted aerial vehicles?
"I've come across open-source projects like ArduPilot that are commonly used with microcontrollers like Pixhawk for unmanned aircraft. However, I'm unsure whether these systems can be adapted for ...
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How elevator and ailerons affect attack and roll angles?
I was trying to model the flight of an aircraft and i need some function that expresses the change of attack and roll angle in function of the elevator and ailerons (respectively).
Does anyone have an ...
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How to slow down while maintaining altitude
Is reducing throttle/power already enough? Or do I have to adjust the pitch as well? If so, I suppose pitching up as well? If pitching up is needed as well, is it because as speed decrease, there is ...
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Are there guidelines for how rudder pedals should be shaped?
I've seen a lot of rudder pedal design, from simple welded steel tubes to more complex branded aluminum forgings.
They all seem to work equally well in my experience, and I've never found myself ...
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Boeing 777 PCU Synchronization of Duplicate Hydraulic Actuators for Control Surface Deflection
I have a question regarding the redundancy of hydraulic systems used to deflect the control surfaces of a Boeing 777 aircraft (or the like). We know that "the elevators, ailerons, and flaperons ...
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Why do the spoilers on the 737 only deploy to the flight detent after a flaps up landing?
Following an all flaps up (no flap) landing, the SPEED BRAKE
lever will not move beyond the FLIGHT DETENT and the spoilers
will not fully deploy (for reference this is stated in the Fcom 9.20.14 rev ...
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How far apart are the rudder pedals on a Piper PA-28?
How far is the left rudder pedal from the right pedal on a Piper PA-28? I assume the left and right seats have equal pedal spacing, but if not, the left seat is what I would like to know.
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Can engines with a fixed nozzle in the angle of attack have the same effect as the thrust vectoring?
If the figure above represents a missile at the angle of attack and we vector resolution the thrust output from the nozzle, we can see that the thrust is divided into sine and cosine parts. Does the ...
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Why is only one rudder deflected on this Su 35?
Why does the aircraft has only one rudder deflected in this picture?
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How to prevent altitude loss or keep flight path angle constant while doing aileron maneuver?
I am trying to perform an aileron roll maneuver for an un-manned aircraft in a simulation. The lateral control architecture is that I am controlling roll rate (stability) with aileron stick and side-...
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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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What causes the "dead band" phenomenon during takeoff on the Boeing 737?
During takeoff, the Boeing 737 encounters a distinctive "dead band" phenomenon after the initial pitch reaches approximately 10 degrees. Essentially, a slight increase in back pressure is ...
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Pitch control in PX4 autopilot
I am trying to translate controller diagram of fixed wing px4 attitude control into mathematical form. While going through the controller diagram Fixed-Wing Attitude Controller looking into PX4 github ...
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What control inputs to make if a wing falls off?
If a wing is severed due to structural damage or from a mid-air collision, what is the best control input to make?
I would think opposite aileron and rudder, i.e. if right wing falls off, input full ...
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How to convert body frame-relative aerodynamic coefficients to wind frame-relative aerodynamic coefficients
I have a rocket flight simulator that takes in aerodynamic coefficients defined relative to the vehicle body frame axes (Cx, Cy, Cz). These are in a lookup table based on mach.
I have some aerodynamic ...
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Why (and how) do aircraft rudders center themselves without input?
Why (and how) do almost all aircraft rudders have some sort of way of re-centering the rudder when there's no input being made? For example, if you wanted to move the flight controls (fly by wire ...
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What safeguards are there against unintended inputs?
A modern passenger jet suddenly encounters some very turbulent air. The captain, who was just enjoying his toilet break, rushes back into the cockpit. Just as he's about to sit down the plane drops, ...
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A plane is flying at constant velocity in equilibrium, then pitches up. What happens?
This might be a dumb question. And I could probably work it out myself. But here goes! Assume a plane is flying along at some velocity $v_0$ at angle-of-attack $a_0$, using throttle setting $tr_0$. ...
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Why do some aircraft's flight control surfaces not droop when hydraulic power is taken away? [duplicate]
Analyzing a bunch of different photos of airliners sitting at Gates, I've noticed that some have flight controls that droop (due to no hydraulic power) and sometimes they stay leveled. Why is this?
...
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How can angle of attack for a T-tail configuration be 21 degrees without stalling and also be flying at its trimmed condition?
I was reading a paper that looks at deep stall for T-tail configurations, and figure 2 suggests that the first trim condition for the aircraft in question occurs at approximately 21 degrees. Surely ...
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