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andreadebiase

When is the right time to turn off A/P while landing?

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When  do most pilots turn off A/P in real life when they want to manually land, at what precise moment during the approach? i'm sure this depends on what's best from a safety standpoint and only the flying crew knows better but let's say you have clear skies and no wind and perfect visibility can a pilot decide to go manual even before intercepting g/s if he wanted to just for the fun of it? is that even an option in an airline?

I pretty much do as per tutorials but i wonder if that is standard policy

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at what precise moment during the approach?

 

Aviation is not formulaic, so you're not going to find a precise point. It will vary by operator, by crew, by plane, and by approach type (or even the specific approach). This topic has come up a number of times in the forum, so I'd suggest searching around a bit to look at the previous discussions.

 

The gist of all of them...?

 

"When you're good and ready to do so."

 

...but I recommend as early as possible so that you can get a feel for the controls.

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When  do most pilots turn off A/P in real life when they want to manually land, at what precise moment during the approach? i'm sure this depends on what's best from a safety standpoint and only the flying crew knows better but let's say you have clear skies and no wind and perfect visibility can a pilot decide to go manual even before intercepting g/s if he wanted to just for the fun of it? is that even an option in an airline?

I pretty much do as per tutorials but i wonder if that is standard policy

 

I think a good idea is, as a general rule, to disconnect the A/P just before reaching 1,000 ft altitude above the landing runway.

Cheers, Ed

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As Kyle mentioned you'll probably get as many varying answers as there are pilots.

But since your asking, I turn off the A/P as soon as I'm stable... that is configured to land, on the alignment, on the glide slope, and trimmed out. 

That is, if that opportunity presents itself. Sometimes the vatsim controllers might bring you in high, fast, or some other direction for whatever reason where you gotta adjust, or just say screw it, click it all off and take control whenever you realize its easier to just look out the window and fly the thing instead of doing it through automation and guidance cues. 

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It will vary by operator, by crew, by plane, and by approach type (or even the specific approach).

 

This is best valid answer you will ever find.

 

Emmanuel Argiropoulos

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Did you know you can fly this airplane without A/P?  Try using the FD from 10,000 to landing... practice.

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Even in IMC (assuming you don't need CAT II / III minimums), there's nothing wrong with hand flying. Automation use is all about workload management. In a low workload situation (descending into a very familiar airport, average traffic density, good weather or at least no convection and above CAT I mins etc), CLICK CLICK and have fun.

 

On the other hand, in a different situation (unfamiliar airport, rapidly developing convection in the area, a total traffic cluster%*@#, controller/pilot language barrier etc), it's probably appropriate to hold on to a higher level of automation a little bit longer, to enable both the Pilot Flying and Pilot Monitoring to expend less mental bandwidth on driving the plane, and more on overall situational awareness. The overriding goal is to use automation as appropriate to prevent either pilot from reaching a state of task saturation.

 

The times I've played with Vatsim, one thing I've found that isn't really modeled accurately on the network is the number of times you're cleared for a visual approach in the real world. Even at large hub airports, in good weather, controllers typically use visual approach clearances instead of the ILSs to keep arrival rate up. Now sure, if you're on a 15 mile final when cleared, you can still let the plane fly the ILS if you want... but what if you're abeam the numbers on downwind? At that point, you're gonna hand fly because it's actually lower workload than trying to figure out the best way to use the automation. This kind of thing happens all the time in the real world.

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Well since we don't have autopilot in the aircraft I fly, it's always off! :P But, most people I've seen while jumpseating, will usually turn it off when stabilized on the approach and some will turn it off passing 10,000 feet. It depends on the pilot and operator. I was flying on a United 319, and the captain hand flew the aircraft up to cruise, and turned off the A/P and auto-throttles right at TOD. 

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Leaving the AP in very late doesn't give you a chance to get a feel for the landing, so don't leave it too late. Also the trim wheel will start clattering away as it prepares for the flare from an autoland at very low level and disconnecting the AP at that point will be, er, interesting!

 

Similarly despite the 'I fly from 25,000 feet all the way to to the runway' brigade in the FS community, a watch of any YouTube video of the said hand flying will show you most approaches are horribly unstabilized.

 

Realistically you're doing the job of two people in sim and if you want to do it all properly, there's no harm in using the automation to help. Many crews won't take out the AP until fully established in the landing configuration, which can be as early as you want it to be but typically is usually around 4/5 miles.

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if you aren't fully comfortable landing the airplane or flying approaches, get the airplane configured in the final landing configuration and when everything is stable, then click it off. This way, you won't have to worry about fighting the airplane through configuration changes.

 

When this becomes easy enough for you, back it up. Click off the autopilot before you drop flaps into their final configuration. This will help you get used to handling the airplane through just one configuration change. When this becomes easy enough for you, disconnect the autopilot one step up. Say before you go gear down. So on and so forth.

 

By doing this, you are learning to anticipate what the airplane is going to do during and after each configuration change. This will help you learn what to do with the thrust levers and yoke.

 

When you can fly an entire it's in visual conditions from a clean configuration to the ground, Start seeing how the airplane behaves to speed changes and decent paths with each configuration. This will help you to see what the airplane is capable of and what you can and can't force the airplane to do in certain situations in each configuration.

 

When you've done all this, hand fly rnav, vor, it's approach from different IAFs.

 

When you feel comfortable enough for all these things, the only determination you will have to make in terms of when to click off the autopilot is if you are or are not to lazy to fly the airplane! haha

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I normally engage it when the SID gets boring to hand fly, and disengage it when the STAR gets interesting to hand fly.

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As all have said, it depends. In my world, we care more about the AP limitations. Jets will have min altitudes for AP use. My personal real world preference is as follows. Crosswinds: I'm a wing low guy, I like to get a feel of rudder and aileron requirement no later than 300ft agl. This gives enough time to warm my hands up and calibrate crosswind controls. Low viz/ceilings, after a long duty day or late night: I use 200ft agl for AP and 100ft for AT. This frees up brain cells and allows me to follow along with my charts. Even when shooting a CATII, I keep the autopilot on until I hear my pilot monitoring state "land". Circling: I keep the AP on until I'm ready to descend out of minimums. I keep the AP in a mode that gives me roll control while the AP holds my altitude. This lets me keep my eyes outside longer without worrying about descending below minimums. The number one gotcha in circling is getting too low and going outside the obstruction radius.

 

Again it all depends. If there's alot of traffic, storms or i can barely understand the controller"foreign flights", I keep the AP on longer to increase my SA and give my pilot monitoring a little relief. Other wise I'm heads down on instruments while the other guy/gal is working my flight guidance panel, radios, FMS, weather radar and looking for traffic. When flying complex SIDs and arrivals, it's better to have 2 guys/gals monitoring and backing each other up instead of one on instruments hand flying while the other is task saturated doing everything else.

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Different strokes for different folks.

 

I usually switch to manual about 5 miles out as I enjoy hand flying and find landing myself is more fun than letting the computer do it.

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Leaving the AP in very late doesn't give you a chance to get a feel for the landing, so don't leave it too late. Also the trim wheel will start clattering away as it prepares for the flare from an autoland at very low level and disconnecting the AP at that point will be, er, interesting!

 

Similarly despite the 'I fly from 25,000 feet all the way to to the runway' brigade in the FS community, a watch of any YouTube video of the said hand flying will show you most approaches are horribly unstabilized.

 

Realistically you're doing the job of two people in sim and if you want to do it all properly, there's no harm in using the automation to help. Many crews won't take out the AP until fully established in the landing configuration, which can be as early as you want it to be but typically is usually around 4/5 miles.

 

The cockpit videos that I've seen, the pilots use autopilot for the biggest part of the approach.  I know that the airline companies that they work for have SOPs that require them to stay on autopilot until a certain point.

It seems to me to be about 1000 ft before they disengage it.

Boeing pilots seem to disengage the autopilot sooner than Airbus pilots.

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I turn it off as soon as I drop below 28,000. Why let the autopilot have all the fun?

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It depends on what I am flying. For private and commercial jets I typically turn it off when given last vector to final on an ILS approach. I then hand-fly the localizer intercept and all the way to the runway.

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