17

The EMB-145 used a combination of FADEC settings and the thrust levers to select the desired thrust and to signify the need for additional thrust. The thrust levers had a detent that selected "100%" thrust for the given mode the FADEC is operating in. If you pushed the thrust levers past the detent to "max" this would give you extra thrust. The mode the ...


14

During the flare somewhere between 25' and 50', the A/T retards the thrust levers to idle. They remain in idle mode until reverse thrust is selected which automatically disconnects the A/T. In the case of Emirates 521, eyewitnesses observed the aircraft do a bounced landing and then attempt a go-around reaching a max altitude of about 150'. Because the ...


13

The Airbus thrust levers can only be moved manually. The levers do not move on their own to reflect the auto-thrust setting. There are detents for the different modes of auto-thrust operation. Regarding the RETARD mode whereby the thrust auto-idles, Airbus doesn't use that (except in autoland).* Hence the callout, "RETARD, RETARD," for the pilots to retard ...


9

EDIT: I take your question as "when crabbing the aircraft for landing in strong crosswind, is the auto-thrust precise enough to maintain horizontal alignment with the extended runway centerline?" No. Auto-thrust is not precise nor responsive enough for this capability. Furthermore, auto-thrust is not used in this manner. To track the extended runway ...


7

caseys answer nicely describes the procedure for the Embraer 145. Since you specifically mentioned the Boeing 737 and Airbus A320, here is how it works for these aircraft: Boeing 737 All Boeing aircraft have autothrottles with servo motors which move the thrust levers in the cockpit. This system is also used to set takeoff thrust: During the preflight, ...


7

Usually power output for a jet engine is gauged from its low pressure turbine speed. In turbofans, this corresponds to the fan speed, displayed as N1. In general, the derated takeoff thrust will be selected based on performance calculations done prior to flight, taking into account weight, runway available, climb performance and ambient atmospherics, which ...


6

The Airbus reference Getting to Grips with Aircraft Performance provides a description in section 4.1 Takeoff Flight Path. They describe the takeoff flight path as four segments as shown in the following figure; They provide the following discussion: So, below 400 feet, the speed must be maintained constant to a minimum of V2. Above 400 feet, ...


6

(Highlight mine.) Short answer: airport briefing. If no restrictions, then company SOP. Thrust reduction is usually set to activate once the plane clears the noise abatement and/or MSA (Minimum Sector Altitude). VNAV takes care of acceleration when activated as long as the SID is programmed. It also warns the crew if constraints will not be met. Boeing ...


6

Because each jet engine only has one lever; each piston engine has three. Jet engine's throttle is pretty straight forward - move forward, more power. The computer automatically manages fuel flow to prevent surge, flameout and N1 overshoot. On a piston engine you have three - a mixture lever, a propeller lever and a throttle lever. Granted, I don't think ...


5

The proper term is "flare" not "flare-out". "Flare" is a term used to describe the act of raising the nose of an aircraft in order to increase lift and stop descending in order to land on a runway smoothly. Whether the pilot, or Auto Thrust does it, a reduction of power to idle is needed in order to bleed off the excess speed that is used during the ...


5

The RTOW (regulatory takeoff weight) charts are runway and configuration specific, so the length and slope (and permanent obstacles) and all taken care of (see red box below). There is no manual formula, either the charts or a performance calculator such as the Airbus FOVE or the company's proprietary software. This is what an RTOW chart looks like: The ...


5

More specifically on your question: See diagram below: In the autothrust mode (A/THR function active), the FMGC computes the thrust, which is limited to the value corresponding to the thrust lever position (unless the alpha-floor mode is activated). So as you can see computers/controllers that control the A/THR are: FCU FMGC/S EIU or EEC ...


5

In its basic form, it is just like the cruise control in a car.* Here is a photo of the autopilot control panel on a Boeing 777. Note the "IAS 200" window on the left: IAS stands for "indicated airspeed". When engaged, this setting tells the auto-thrust to adjust engine power to maintain 200 knots of airspeed. Just like a car, when you go uphill you need ...


5

They can be used individually, yes. When flight directors (or autopilot) are on then they dictate what auto throttle should do. But it's not a good idea to fly manually, use auto throttle and have flight directors still on and here is why: When autopilot is off but the flight directors are on and auto throttle is on you can select a vertical mode like ...


4

Yes it can. Autothrottle on most large aircraft (including 777) is considered a separate system from autopilot. To that end, the modules/boxes that control the autothrottle and autopilot are separate as well. This adds a bit of redundancy in that losing autopilot doesn’t mean you also lose autothrottle and vice versa. Edit: I couldn’t find a clear system ...


4

You are correct that different planes operate slightly differently, but they are mostly pretty similar. Just as with the autopilot, the autothrust can be disconnected and the airplane can be controlled manually. Below is an image of the Mode Control Panel on the 737 NG, which is located just below the windshield. The section that controls autothrust is ...


4

Boeing's officially stated reason in the report is: ... to prevent pilots from inadvertently activating TO/GA mode at or after touchdown. Inadvertent activation of TO/GA could result, among other things, in the aircraft departing[1] the runway. ... [1] As in runway overrun/excursion. Which is in accordance with AC120-29A (also from the report), where: ...


4

From your question, it seems that you have the following situation: An aircraft is having a constant angle w.r.t. the runway to compensate for a crosswind. When this crosswind increases, the aircraft will as a result drift off the centerline of the runway. To compensate this, you imagine the aircraft speeding up to 'catch' the centerline. Note that I'm ...


3

@JuanJimenez's comments are correct. N1 (and the accuracy of EPR) are not indicators of a precise thrust force. So to answer the title question, generally no, moreover the acceleration of each engine may be different, and that is why the pilots go through a stabilization step, where they apply some thrust, make sure they're responding in a sufficiently ...


3

This depends on the aircraft. Airbus aircraft have a managed speed mode in the FCU (flight control unit), where the speed is completely controlled by the FMGS (flight management and guidance system). This includes slowing the aircraft down when the appropriate flaps are selected by the crew. No manual action is necessary to reduce airspeed for landing until ...


3

The autothrust functions in the A320 are performed by the Flight Management and Guidance Computers, or FMGCs (what you call autopilot computers -- they indeed handle autopilot duties as well).


2

The question was not whether the autothrust/autothrottle DOES keep the aircraft aligned, but whether or not it CAN keep aircraft aligned. There is a very interesting, but not well known story that took place after United Airlines Flight 232 crashed in Sioux City in 1989. After having lost all hydraulic power on a DC-10 aircraft due to a failed disc on the #...


2

High speed protection is still available (in normal law) in SRS (check FCOM DSC 27 20-10-20). What you will not have is the reversion mode of the autothrust to Speed. You will get the protection (THS freeze, spiral stability to 0deg, max 40 deg bank, nose up order) but thrust will remain in THR CLB. I suspect the reasoning was that SRS mode implies you ...


2

In AIRBUS, The «Flare mode» brings automatically the thrust to idle provided the autothrust is under the dependance of the FMGS, in this case irrespective of the pilot action moving back the levers or not, the thrust will go to idle. On the other hand if the approach is done in SPEED mode AND WITHOUT THE AUTOPILOT USED IN PARALLEL, it is mandatory to move ...


1

enter link description here A320 ECAM "WHEEL" page The answer: The LGCIUs (landing gear control and interface unit) receive position information from the landing gear, cargo doors, and landing flap systems and process gear and door position, sequencing, control, and gear lever selection. When one of two LGCIU is inoperative (№6) amber XXXs in the ...


1

The term may also be ITT limit (Inter Turbine Temperature). On most engines there is usually a 2 minute to 5 minute limit on EGT/ITT and N1 (fan rpm) for both Take-off/Go Around power, and APR (Automatic Performance Reserve) power (the balls-to-the-wall thrust setting the engine automatically goes to when the other engine quits). On most FADEC engines, the ...


1

The TO/GA time limit and the EGT limit are hard limits mandated by the approved flight manual. They must be adhered to independently and cannot be traded off between the two. Takeoff performance is calculated so that if a safe altitude above terrain and obstacles cannot be reached within the time limit, aircraft mass must be reduced rather than the TO/GA ...


1

TOGA LK is short for Takeoff Go-around (Power) Locked. Which means, due to some kind of situation (e.g. reaching Alpha Floor), the aircraft decided it'd be a good idea to spool the engines up to maximum thrust. It will remain at that power setting no matter what the thrust levers were set to before the TOGA LK state was applied by the aircraft, hence "...


1

Are you talking about a "flare"? Or a "flame-out"? A flare is part of the landing sequence. You raise the nose of the airplane so that you touch down gently on the main gear. The engines need to be at idle (or at least, low thrust) at or before that point because the whole point of landing is to come to a stop. A flame-out is what happens to a turbine (jet)...


1

The Flight management and guidance system (FMGC) performs the following functions: Autopilot Flight director autothrust flight management The FMGS sends the thrust commands for the autothrust function to the ECU1/EEC1 to set the thrust command on the engine 1. ECU2/EEC2 to set the thrust command on the engine 2.


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