I was wondering about this since flap movement is tied to variables like weight and speed. Could flight deck automation remove from pilots the task of lowering and raising flaps based on aircraft configuration?

Moving the flaps is not an onerous task. Farming it out to automation, while certainly possible, takes the pilot out of having control over the configuration of the aircraft. There’s no reason to do this.

First steps are already done: on the A350, the flaps automatically optimize the wing profile depending on weight and balance without any interaction from the pilots.

The advanced flap concept provides benefits during cruise as well. Rather than having a static wing profile, the new flap allows varying camber (wing profile) options as the aircraft burns fuel and loses weight during flight. Drag can be reduced by up to two per cent at high gross weights, resulting in considerable fuel economies. Moreover, weight savings on the order of half a tonne for the wing box are feasible by using differential flap settings to alleviate manoeuvre loads.

https://www.airbus.com/newsroom/news/en ... vings.html

I've read a similar system is planned for the A321XLR.

By far not the fully automated control of the flaps, but a step towards more automated and optimized systems. However, I believe it is still a long way until flaps will deploy and retract without any input from the pilots. And I'm not unhappy about that. A pilot should always be in full control of the aircraft's configuration. Maybe more advisory can help, but letting the aircraft reconfigure its own aerodynamics without pilot interactions seems a bit risky to me.

Quite a few military airplanes, in particular the Me262 and the F86 have aerodynamically ("floating") leading edge devices that operate on their own.

Some modern military airplanes also have leading edge devices that move pn their own according to the demands placed upon the airplane by the person pulling on the joystick. In the F16 Thunderbirds accident with the dramatic ejection footage, you can see the slats automatically deploying.

SteelChair wrote:

Quite a few military airplanes, in particular the Me262 and the F86 have aerodynamically ("floating") leading edge devices that operate on their own.

Some modern military airplanes also have leading edge devices that move pn their own according to the demands placed upon the airplane by the person pulling on the joystick. In the F16 Thunderbirds accident with the dramatic ejection footage, you can see the slats automatically deploying.

Handley-Page slats are an old design and quite widely used—Helio Courier, the F-86 and F-100, the Sabreliner 40 & 60. They are spring loaded and respond to AoA. On the Hun, in 1G flight they deployed (fell out would be more accurate ) at about 290 knots. On pre-flight, we pushed them in and out to check for free movement. Before any ACM, the flight would do a slat check, dive to 390-ish and pull some G to ensure even deployment.

https://en.wikipedia.org/wiki/Leading-edge_slat

convair880mfan wrote:

I was wondering about this since flap movement is tied to variables like weight and speed. Could flight deck automation remove from pilots the task of lowering and raising flaps based on aircraft configuration?

Yes. In fact, right now flaps are typically set to one of a few positions. If automated, they could be set to exactly the right position for each moment of flight (with the additional rule that we cannot adjust every second, lets not wear out the mechanism.). Imagine a plane that every 10 seconds put the flaps into the best lift/drag position for each moment of climb, adjusting them by maybe 1 degree each movement.

On landing, instead of dragging the gear through the air while the engines are above idle, keep them retracted and have them come out only when either very close to landing or the extra drag is needed. This would save fuel, and also a surprising amount of noise.

By scheduling flaps/gear more efficiently, you could save a bit of fuel and noise.

Auto throttle exists. Auto braking exists. Fuel management (moving it forward and back to get lowest drag center-of-gravity) is a thing. In fact, almost always on almost all airlines, the autopilot is flying.

But pilots will want to feel "in control" and will resist new automations. Each one of those was resisted. As a pilot I understand, but as a consumer of airline tickets, I'd like to save money.

While Airbus does not have automatic flaps it can do something similar during the approach: it can automatically reduce to maneuvering speed for the current flap setting (if the speed is in "managed" mode while the FMGC is in approach phase), so it's possible not to touch the speed knob during the whole approach as it's automatically adjusted down with each new flap selection until reaching final approach speed. In practice this feature is not used very often used for the whole approach as ATC often assigns speed restrictions or pilots prefer to fly the approach slightly faster than maneuvering speed (a usually schedule advised by ATC could be 160kts to 4 miles from touchdown - a typical ILS approach would usually be flown with Flap 2 (and gear still up) from FAF until around 5-6 miles, but the maneuvering speed for Flap 2 is usually well below 160kts, so pilots would "select" the speed, i.e. override the automatic speed selection in managed mode).
I know this is not exactly what you are looking for, but it fulfills the same purpose: in a conventional aircraft the pilot have to select both speed and flap setting manually, by either automating the flaps selection (as in your proposal) or the speed selection (as done by Airbus) you will take quite a bit workload from the pilot. I think the solution by Airbus is the better way as it's more intuitive and easier to manually change the speed selection than to select some sort of "override" on an automatic flap system, if needed due to operational constraints.

Slats deploy automatically in Socata Rallye Commodore:

https://www.airliners.net/photo/Ilmasot ... Mod/419561

I don't know if it has been used in any other GA aircraft

The flaps on a f-18 are automated, You have 3 positions half full auto. Based on the flap setting, the airspeed, the airplane alpha, the flight control system positions the leading edge and trailing edge flaps automatically


I guess you could have a system similar to autothrust where TLA tells the system what the maximum thrust setting the autothrust system is allowed to command. The flap handle would be used to tell the flight control system what setting the maximum flap position it is allowed to auto deploy and auto retract.

You’re at 300kts and you select flaps full. Since you’re over the flaps limit speed the airplane doesn’t do anything. As the plane slows below 230kts flaps 1 deploys, then below 190 the flaps goes to flaps 2 automatically, and so forth.and when you speed up, the flaps auto retract just like when the speed increases above 210 the slats auto retract.

For some situations, automatic flaps already exist.

On the Airbus (330/340) we have two automatic systems:

Flap Load Relief System (FLRS): It is a protection and usually not used intentionally. With configurations 2, 3 or FULL, when exceeding the maximum speed for the actual configuration by 2.5 kts, flaps will retract to their next position. The most common situation where the system is activated is in gusty situations on a heavy aircraft, when the minimum speed for the actual configuration is close to the maximum speed of the next configuration. In this situation, if you extend Flaps/Slats to the next step and hit a gust, you may exceed your maximum speed for a short moment and the system reduces the load on the flaps by retracing them (flaps only). Once below maximum speed, they will extend again automatically.

The second automatic system is closer to the idea of the OP: The Automatic Retraction System (ARS). It is used during clean-up. With configuration 1+F (Slats and Flaps at position 1), the flaps will automatically retract to 0 (Slats remain) at 200 kt (before maximum speed of Flaps, which is 215kt). On a heavy A340 configuration 0 can only be selected at speeds well above 215kt, therefore you would hit the maximum flap speed before you can select configuration 0 without this system. This system comes closer to the idea of the OP, as it is used operationally on each (heavy) departure.

The idea of a fully automated system could make sense for the climb out. During climb you are always interested in having an optimised configuration for your actual speed and too much drag is never good.
For the approach case I would be very sceptical. When flying at a certain speed (e.g. advised by ATC) and I am below profile, I'd like to stay as clean as possible (for economical, noise reason). However with the same speed but above my profile, I may want to add more drag by extending flaps/slats as early as possible. And an automated system can not think ahead. When I know, I am allowed to reduce speed at a certain point on final approach, I can select the next configuration shortly before this point and have the necessary drag ready exactly at the moment when I want it.

kitplane01 wrote:

convair880mfan wrote:

I was wondering about this since flap movement is tied to variables like weight and speed. Could flight deck automation remove from pilots the task of lowering and raising flaps based on aircraft configuration?

Yes. In fact, right now flaps are typically set to one of a few positions. If automated, they could be set to exactly the right position for each moment of flight (with the additional rule that we cannot adjust every second, lets not wear out the mechanism.). Imagine a plane that every 10 seconds put the flaps into the best lift/drag position for each moment of climb, adjusting them by maybe 1 degree each movement.

On landing, instead of dragging the gear through the air while the engines are above idle, keep them retracted and have them come out only when either very close to landing or the extra drag is needed. This would save fuel, and also a surprising amount of noise.

By scheduling flaps/gear more efficiently, you could save a bit of fuel and noise.

Auto throttle exists. Auto braking exists. Fuel management (moving it forward and back to get lowest drag center-of-gravity) is a thing. In fact, almost always on almost all airlines, the autopilot is flying.

But pilots will want to feel "in control" and will resist new automations. Each one of those was resisted. As a pilot I understand, but as a consumer of airline tickets, I'd like to save money.

Just a guess here, but you haven’t operated a jet of any size in the real world of ATC, airports, weather, etc.

convair880mfan wrote:

I was wondering about this since flap movement is tied to variables like weight and speed. Could flight deck automation remove from pilots the task of lowering and raising flaps based on aircraft configuration?

Yes, it is possible.

No, it is not welcome. And not for a "human don't like automation" factor.

As GalaxyFlyer stated, there are many variables. On departure, you (usually) have three or four of flap settings to account for contaminated runway, ISA offset, required climb gradient and tens of other safety/operational reasons.

Similar on landing. Is there a contaminated runway? Is wind gusting? Windshear perhaps? What is landing weight, and how it will influence landing distance? Heck, even airport knowledge and taxiway for vacating do matter. It saves fuel and time to leave runway exactly where your target terminal is.

Plus a number of different other considerations. When stuck up there and trying to get below MLW (be it for better winds than predicted, shortcuts, or simply when trying to bring bird down under some sort of non-critical problem), high speed - high drag config is something you're looking for. And having a system automatically reducing flaps when you really need them, is the last thing you need.

So, again - it is quite possible, but not welcome for a number of reasons. Some stated.

Cheers,
Adam

Many folks beat me to a few comments like the NA Saberliner slats, I remember them as just on rollers, no springs. The co-pilots, like me, got to polish them weekly! As well as the comment on weather, ATC, etc. Along those lines, if flaps were automated then you'd need to be able to disable the system for all flap abnormals.

Yeah, rollers, no springs.

Don't know if it was mentioned, but in the F-16 both leading edge and trailing edge flaps are automatic and controlled by the flight control system. There are override switches to use in abnormals or emergency procedures.
Good discussion here
https://www.f-16.net/forum/viewtopic.php?f=21&t=28990
:

RetiredWeasel wrote:

Don't know if it was mentioned, but in the F-16 both leading edge and trailing edge flaps are automatic and controlled by the flight control system. There are override switches to use in abnormals or emergency procedures.
Good discussion here
https://www.f-16.net/forum/viewtopic.php?f=21&t=28990
:

Learned something new. Particularly how it works. Thanks.

So I should have written "is done" instead of "could be done".

gloom wrote:

convair880mfan wrote:

I was wondering about this since flap movement is tied to variables like weight and speed. Could flight deck automation remove from pilots the task of lowering and raising flaps based on aircraft configuration?

Yes, it is possible.

No, it is not welcome. And not for a "human don't like automation" factor.

As GalaxyFlyer stated, there are many variables. On departure, you (usually) have three or four of flap settings to account for contaminated runway, ISA offset, required climb gradient and tens of other safety/operational reasons.

Similar on landing. Is there a contaminated runway? Is wind gusting? Windshear perhaps? What is landing weight, and how it will influence landing distance? Heck, even airport knowledge and taxiway for vacating do matter. It saves fuel and time to leave runway exactly where your target terminal is.

How much of this does the computer already know? I'm sure it knows landing weight and sometimes knows intended taxiway. I don't think it knows winds.
But if the auto throttle can achieve V+extra, surely the auto flaps can do that too.

convair880mfan wrote:

Plus a number of different other considerations. When stuck up there and trying to get below MLW (be it for better winds than predicted, shortcuts, or simply when trying to bring bird down under some sort of non-critical problem), high speed - high drag config is something you're looking for. And having a system automatically reducing flaps when you really need them, is the last thing you need.

Related question. On large jets, when you're too high and too fast and want to lose energy, is the engine at idle or some higher setting?
How often are your burning fuel to get below MLW?

Surely, at idle plus some drag devices which, depending (always the correct answer) on situation, could be gear, flaps, speed brakes or some combination.

I’m not sure what advantages there’d be for automating basic controls. It’s hardly a workload issue, the “tactical” situation varies and gear and flap settings are a pilot’s way of dealing with them. Optimizing high lift settings on climb might create some rather small efficiencies at added cost of failure mode analysis and how to address them.

kitplane01 wrote:

gloom wrote:

convair880mfan wrote:

I was wondering about this since flap movement is tied to variables like weight and speed. Could flight deck automation remove from pilots the task of lowering and raising flaps based on aircraft configuration?

Yes, it is possible.

No, it is not welcome. And not for a "human don't like automation" factor.

As GalaxyFlyer stated, there are many variables. On departure, you (usually) have three or four of flap settings to account for contaminated runway, ISA offset, required climb gradient and tens of other safety/operational reasons.

Similar on landing. Is there a contaminated runway? Is wind gusting? Windshear perhaps? What is landing weight, and how it will influence landing distance? Heck, even airport knowledge and taxiway for vacating do matter. It saves fuel and time to leave runway exactly where your target terminal is.

How much of this does the computer already know? I'm sure it knows landing weight and sometimes knows intended taxiway. I don't think it knows winds.
But if the auto throttle can achieve V+extra, surely the auto flaps can do that too.

convair880mfan wrote:

Plus a number of different other considerations. When stuck up there and trying to get below MLW (be it for better winds than predicted, shortcuts, or simply when trying to bring bird down under some sort of non-critical problem), high speed - high drag config is something you're looking for. And having a system automatically reducing flaps when you really need them, is the last thing you need.

Related question. On large jets, when you're too high and too fast and want to lose energy, is the engine at idle or some higher setting?
How often are your burning fuel to get below MLW?

The computer knows landing weight. It knows intended taxiway if you tell it. It knows the reported wind at the runway, and the instantaneous wind at your position. However, it does not know what ATC will tell you, or if there's a storm cloud in your path, or if the aircraft ahead of you is a bit slower than expected, or if ATC will give you a speed restriction, and so forth. All these tactical considerations mean manual flap control is important on approach.

If you're high/fast and want to lose energy, the engine is at flight idle.