Mode Review. Here are the topics for this lesson. FMA’s Review Mode Overview Vertical Profile Performance Modes Levels of Automation VNAV General Concepts.

Vertical Profile Navigation

Mode Review

Agenda

Here are the topics for this lesson.

FMA’s• Review• Mode

Overview

Vertical Profile

• Performance Modes

• Levels of Automation

VNAV• General

Concepts• Operation

You fly the 767 primarily using the Autoflight Control System. Manual flying is at a minimum.

Autoflight Control System (AFCS)

The autoflight control system contains the autopilot/flight director system, the thrust management system, ……

You use the Mode control panel for aircraft control using the autopilot, or to control the flight director guidance for manual flight.

Indications for the engaged modes are the flight mode annunciations.

Lighted switch indicates mode acceptance by the FCC, not engagement

You need to always be aware of the engaged modes to know what the airplane is doing or what the guidance for the flight directors will be.

You need to include in your scan the FMA’s.

To maintain positive control of the airplane, you need to always be aware of the engaged mode AND know what that mode does.

You need to always be aware of the engaged modes to know what the airplane is doing or what the guidance for the flight directors will be.

Asiana example do you know what IDLE mode will do?

Flight Modes Annunciations

Thrust Pitch Roll

Autoflight Modes

Autoflight Limit Modes

1. Pilot assist modes3. Automatic Modes

2. Pilot controlled command modes

Automation Levels

Different modes offer different levels of automation. The more the automation takes over, the more your workload is reduced… unless it isn’t doing what you expect it to do. To minimize this, you need to have an understanding of how the automation works in different situations.

The more automated, the less direct control you have

Another way to look at the FD

Obviously it is vital to understand the modes indicated on the ADI. Interpreting the indicated modes lets you know how the airplane is controlled and what it will do. Some modes such as LNAV and VNAV have more hidden rules. You must understand those rules to know how the airplane is controlled.

Mode Axis Control

Modes can control one or more axis. For instance when you select VNAV or FLCH you engage both pitch and thrust. Selecting vertical speed only engages pitch.

Thrust Only

Pitch Only

Roll Only

Thrust & Pitch

Pitch & Roll

Thrust, Pitch & Roll

Computer Brains

The thrust management computer, flight management computers, and flight control computers are the main computers calculating the control laws for flight guidance.

TMC FMC’s FCC’s

Thrust Mode Indicator

This mode indicates how the thrust is controlled.

Thrust Management System

The thrust management system controls the autothrottle. A thrust management computer actuates the throttles based on inputs from the mode control panel or from FMC commands when you engage VNAV.

TMC Modes

Notice the A/T arm switch is right above the commands to engage the TMC in THR (N1) or SPD modes. The TMC moves the throttles as required to maintain the limit N1 in THR mode or the reference speed in SPD mode.

Flight Path Modes

These two modes determine the guidance of the flight path. The flight director indicates the desired pitch and roll.

Who’s Controlling Mode

This mode indicates who is actually following the flight path guidance; you or the autopilot.

If you see FD, maybe it’s a good idea to grab ahold of this thing (if you haven’t already)

Performance Modes

Now that we had a short mode review, let’s look at the performance modes.

Vertical Guidance

When you enter SID’s, STAR’s and a cruise altitude, you provide the FMC with a set of vertical legs. These legs specify the type of performance desired to control airplane’s pitch & thrust axes within constraints of flight plan.

Power + Pitch = Performance

Remember when you were just learning this stuff

FMC’s

Another way to look at the FD

Three Flight Segments

The Vertical profile is partitioned into three flight segments.

For speed on elevator, the speed is maintained until the specified target altitude is reached. Speed on elevator is used for climb, cruise climb, cruise descent and speed reversion with respect to the descent path.

Vertical (performance) legs

• Like lateral legs

Vertical (Performance) Plan Legs:

A leg may use more than one type of control mode

Speed/Thrust Airspeed on elevator thrust on throttleV-Path/Speed Vertical path on elevator airspeed on throttleCruise Descent Airspeed on elevator thrust to computed value then HLDV-Path/Idle Vertical path on elevator throttle IDLE speed control through speed

brakes, or autothrottle mode request, or manual throttle if A/T disengaged

Speed/Idle Airspeed on elevator throttle to computed idle, then airmass performance

Speed Reversion Backup for V-Path/Idle to Speed/IdleGamma Hold Backup for speed on elevator - prevents inadvertent climb in descent

or descent in climb - controls to fixed descent or climb rate with elevators

Vertical Speed Submode of speed on elevator in selected E/O driftdown cases. Elevators control descent rate to 300 fpm and throttle controls speed.

Five flight phases to be predicted:

Takeoff – engine start, taxi and takeoff through cleanupClimb – cleanup to cruise altitudeCruise – until T/DDescent – when airplane leaves cruise altitude, descending to destination to approachApproach – initial flap extension point to touchdown

A lot is going on in the computer that is not annunciated. The VNAV switch is OVERLOADED according to human factor design.

When reaching cruise altitude

Speed changes in VNAV during cruise

Active speed

Execute CDU entryExecute ENG OUT or LRC

Or Speed Intervention

Determining impact of speed change

During Speed intervention

Descent

An autopilot caution occurs if the autopilot stops operating correctly, but does not disconnect.

A yellow line crosses the mode annunciation. Also the related flight director bar(s) disappear.