Questions tagged [autopilot]
An autopilot is a system used to guide an aircraft without assistance from a person.
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Acceleration command in proportional navigation?
I was recently taking a gander at proportional navigation, a missile guidance law, and I noticed most PN laws output something known as an acceleration command. The acceleration command is a command ...
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Why would autopilot be prohibited below 1000 feet AGL?
Came across this airplane on controller. It has a label on the panel that says: "Autopilot prohibited below 1000' AGL".
Why?
(source)
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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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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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Standard Airliner Roll Rates Under Autopilot Control?
Do Boeing-Airbus planes under autopilot control adhere to standardized roll rates during routine maneuvers?
For Example: A 5 degrees per second roll rate between 0 and 20 degrees of bank?
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Thoughts on Idea - AP Disengage, Land Flap Selection
When AP disengages the aircraft goes into a slight roll or the possibility exists for the aircraft to go into a degree of roll.
Do you think it would be prudent for airlines to include as an SOP for ...
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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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Garmin autopilot question
I recently took a check out in a Cessna 172 with a Garmin GFC 500. My instructor had said when the plane was turning on nav mode, to not select a different heading opposite of the turn and switch to ...
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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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ILS Frequency Assignment In Dual Nav Radio Setup
With a dual Nav radio setup (On autopilot panel) does the ILS frequency of the runway you're about touch down on need to be entered into both radios or just one? Cheers.
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Is an autopilot failure an emergency?
If the autopilot of an airliner fails, but everything else still works, weather conditions are good, and the pilots are able to hand-fly the plane with no problems, is this an emergency? Would they ...
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Why did autopilot switch to CWS P on a LNAV/VNAV approach, and why didn't it reduce descent rate to comply with CDU alts when VNAV was re-engaged?
We were performing an NDB approach the other day due to the ILS being unserviceable.
We are flying a 737-800, FMC Update 14.0 (“common VNAV”)
We were using LNAV and VNAV as our roll and pitch modes ...
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Helicopter autopilot
Is there any video or explanation how parallel actuators work on 4 axis helicopter autopilot ?
I am familiar with beep trim and trim release buttons, but want to know how it all works in the ...
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Are there any autopilots that are capable of landing a damaged aircraft better than any human?
How close are we to commercial aircraft with autopilots that can, as safely as theoretically possible, land an aircraft with damaged, missing, or otherwise inoperative control surfaces; or altered ...
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Why do we still use pilots to fly airplanes?
With the recent advances in drone and remote control technology, why are there still commercial and military pilots?
I understand that there can be some serious tactical advantages to human pilots in ...
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How do I get rated to fly complex aircraft that are still Microlights?
In the most recent issue of the BMAA magazine, there are new aircraft listed that are still Microlights, but have complex features. These include Autopilot(!), retractable landing gears and even ...
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How do aircraft instruments determine the aircraft's orientation relative to the ground?
Autopilots exist for airplanes and drones, how is orientation measured with respect to ground? In particular how is the direction of gravity detected and how is it differentiated from acceleration due ...
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Was there an incident when Airbus autopilot wasn't letting the airplane land?
I'm trying to track down a story about an incident involving an Airbus airplane my father told me about 25 years ago, when he was working at a Boeing supplier.
Reportedly, what happened was the ...
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As of 2023, why do we still not have an airplane that can be operated by a person with very little training?
In the past 20 years the following technologies reached full maturity:
Computers now have immense computation power, sufficient to process real-time video with several backup systems for a relatively ...
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When to disconnect the A/P on approach in an airliner?
I've looked at the other question asking about when to disconnect the AP on an airliner and I get that it's very situational depending on the pilot and conditions.
I've found I'm too reliant on the ...
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Why would planes with two autopilots have just one active during cruise?
I know that the plane must have two autopilots for flying approaches, but why have individual buttons for each autopilot? Wouldn't it be easier to have both autopilots work at the same time for the ...
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Why are the A300/310’s electric pitch trim switches inhibited with the autopilot engaged?
The A300/A310, like most other aircraft (except for some small general-aviation aircraft), has an adjustable-incidence-angle horizontal stabiliser, which is used to trim the aircraft in pitch (for ...
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Why do autopilot controllers use $\theta$ as the input signal rather than $\gamma$?
In particular, referencing how the Matlab/Simulink controller here uses $\theta$ (absolute pitch angle), rather than $\gamma$ (flight path angle). (Autopilot controller starts at 59:26)
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How do autopilots maintain/adapt wind crab angle while flying a certain course over the ground?
How do autopilots maintain/adapt the wind crab angle while flying a certain course? With ailerons or rudder, or both?
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What does the term "Course Cut Limit" mean in relation to an autopilot?
In several manuals detailing the autoflight systems of some aircraft, it is common to see the VOR/LOC capture mode have something called a 'course cut limit.' What is this term referring to? I am ...
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Boeing 747 Autopilot Pitch Modes Logic (Path Integrator)
I am hoping this will be my final question(s) concerning the 747 autopilot, given that the roll modes are now complete and I am finally on to the pitch modes...
All information on how this autopilot ...
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What is the largest aircraft ever successfully flown and landed with no pilot on board?
I'm not sure if this belongs here or on the drone site.
What is the largest aircraft (not spacecraft) that has completed an entire flight, including takeoff and no- or minimal-damage landing, either ...
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How much thrust should be applied when you set the autopilot to a specific altitude?
After a plane takes off the pilot usually sets the autopilot to the altitude of the flight level they are about to cruise at, e.g. 30,000 ft, right? When that is the case, how much thrust should be ...
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TruTrak Vision PMA Autopilot Limitations for coupled instrument procedures- C172M - STC SA04231CH
I am currently flying a Cessna 172M with a TruTrak Vision Autopilot installed under STC SA04231CH. Section 2.4 of the approved AFMS states:
This autopilot has not been evaluated by the FAA to meet ...
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Why would the 737 autopilot A disengage without engine-driven hydraulic pump during heavy demand?
Note: Loss of the system A engine-driven hydraulic pump, and a heavy demand on system A, may cause A/P A to disengage.
Just finding it difficult to understand why the A/P would disengage in this case....
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Can the 737 Max autopilot be engaged when some sensors have failed?
If some instruments on the 737 MAX 8 fail on the Captain's side and autopilot stops, can the First Officer engage autopilot (as the instruments on his side are fine)? In the ET 302 crash the Captain ...
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What is needed in a plane to fly approach mode?
Do you need anything other than approach mode to be able to have the plane fly the ILS to minimums? Do you need a EFD (glass cokpit) or can it be done with steam gages as well?
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How may I verify WAAS channel number on G1000?
Take RNAV (GPS) Y RWY 36L and RNAV (GPS) Z RWY 36L at APC for examples,
All fixes and routes in the two approaches are similar.
The noticeable differences that I observe are minimums and WAAS CH ...
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Are stories of autopilots in things like the J-3 basically urban myth?
While my own research makes plain that the Cub-owning community seems to consider the idea of installing even the most basic autopilot into a Cub a mortal sin, there are scattered accounts on the web ...
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Will the autopilot raise the AoA above the critical AoA to maintain altitude?
NOTE: This question is regarding commercial airliners (eg: Boeing 737, Airbus A320, etc.. This is for any given configuration of the aircraft)
Will the autopilot raise the AoA above the critical AoA ...
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Why is the autopilot called "George?"
The autopilot of an airplane is frequently referred to as "George" (for example, in this answer). When did this nickname enter common usage, and what is its origin? Please cite sources if possible!
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What happens if the autopilot fails to initiate a flare?
What are the chances of autopilot failing to do a flare in an otherwise stable autopilot controlled approach and landing? Has it happened before and how was it dealt with?
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How do airplanes measure cross-wind?
Are aircraft equipped with any instruments that measure actual crosswind velocity during a flight? What is that instrument called and is it used by autopilots to apply wind correction?
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Is there an FMC not connected to the AP/FD?
Is it possible to have an FMC to compute the performance and navigation without having it linked to an autopilot or flight director?
Does/did such setup exist?
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What is the difference between autopilot and fly-by-wire system?
I observed a lot of people misinterpret these words. In my opinion, autopilot assists the pilot by inputting the commands to the computer whereas fly-by-wire (FBW) system sends and receives signals ...
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What is the vertical speed limit when altitude mode is engaged?
This question applies to Airbus' autopilot but may not be restricted to just this manufacturer (there must be equivalent modes on ATR, Embraer, Dassault Falcons, etc.)
For the vertical plan, the ...
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Does an autopilot that controls roll, pitch and a yaw damper meet the requirements of 135.105(c)(1)?
For single-pilot VFR operations, 14 CFR 135.105(c)(1) requires that:
The autopilot is capable of operating the aircraft controls to
maintain flight and maneuver it about the three axes
Does this ...
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Feasibility and process for the approval of a modified glider [closed]
I am looking into a business idea that requires glider sized semi-automatic drones but I am very naive when it comes to the regulations and rigour of the aviation and airline industry, so I am hoping ...
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Why does an A300/310 in LAND or GO-AROUND mode have to be at least 400 feet AGL for manual control column movement to disengage the autopilot?
Each of the A300/310’s two autopilots has two modes of operation:
In CWS (Control-Wheel Steering) mode, the autopilot(s) attempt to hold the attitude that the aircraft had at the moment of autopilot ...
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Can a normally poorly handling airframe with high moments of inertia actually have superior flight dynamics under autonomous control? [closed]
I’m not a pilot but know a thing or two about flight dynamics. As you know there are currently quite a few aircraft under development designed for low-and-slow and (eventually) autonomous flight. ...
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Can autopilot track ILS without any internal heading reference?
I am asking about the internal design of the autopilot of a CRJ200 (no autoland).
I was flying an ILS approach when the AHRS heading started to drift rapidly by 30 degrees. The autopilot somehow was ...
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Do modern aircraft require rudder input in order to perform a coordinated turn?
With today's state-of-the-art electronic systems in modern aircraft, do aircraft equipped with autopilot systems, still require pilot rudder input to keep a turn coordinated?
For the context, I'm ...
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Does the Autopilot switch to ALT ACQ mode at a fixed altitude difference from target altitude?
For example, if climbing (or descending for that matter) at 3500 fpm, will the AP switch to ALT ACQ mode at the same point it will as when climbing or descending with 1000 fpm? Or does the point of ...
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How do I set up G1000 GFC700 autopilot for takeoff?
I want to be able to engage autopilot right away at a safe altitude, while taking advantage of flight level control at Vy for the climb.
Heading is set for the runway. I’d switch to NAV mode when I ...
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Choosing $\phi/\beta$ in Lateral-directional control design
In designing the Lateral-directional controller for aircraft, there is a parameter called $\phi/\beta$ that is defined as the ratio of the magnitude of the bank angle to the sideslip envelopes in the ...