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aircraft:dash8-q400_flight_deck

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Introduction To The Flightdeck

Take your time and look around the Cockpit for a bit. Read the panel names and get an idea where which panel is located. Lets start a bit of a tour through the flight deck of the Q400. Directly in front of the pilot there are two monitors. The left one is the primary flight display (PFD) and the right one is a multi function display (MFD) currently showing the navigation display page (ND) with the flight plan and waypoints on it. The bottom half of the MFD shows the positions of the Primary Flight ControlS (PFCS). In the center of the front panel we find the Engine Warning Display (EWD) that indicates the status of the engines, most interestingly to us: torque (TRQ) precentage and propeller rotation speed (PROP RPM). Directly above the EWD, in the glareshield, you can find the Flight Guidance Control Panel (FGCP) also called autopilot panel, which we will use to interact with the autopilot.

PFD

The PFD displays, left to right, the current airspeed, the attitude, the altitude and the vertical speed. In the lower half of the display you find the horizontal situation indicator (HSI). The primary flight display is the most important display in the entire cockpit. For that reason it is place directly in front of the pilot.

The PFD is split into several parts:

  • FMA - Flight Mode Annunciator with the lateral flight guidance mode on the left and the vertical mode on the right in green as well as armed modes in white in the second line
  • FD - single cue Flight Director that moves up and down to command pitch angle changes and pivots left and right to command bank angle changes
  • IAS - Indicated AirSpeed with readouts of V1 (takeoff go-speed), VR (takeoff rotation speed), V2 (takeoff climb speed with engine failure), V FRI (flap retraction speed - solid triangle) and V Climb
  • ATT - ATTitude indicator displaying pitch and bank angle as well as side slip (white trapezoid at the top)
  • ALT - barometric ALTitude in feet as well as selected altitude at the top as digital readout
  • VS - Vertical Speed with a white needle and a digital readout of the current vertical speed above and below the scale in 100 ft/min
  • RA - Radar Altitude digital readout of the height above terrain in feet
  • HSI - Horizontal Situation Indicator that shows the selected heading on the left as well as a heading bug around the compass rose in the center, current heading is up on the display, a deviation bar to indicate the offset of the selected navigation source and on the right a legend to show which navigation source is selected as well as it's course.

Setting V-Speeds

  • Click the SELect button next to the PFD to select a line in the v-speeds to edit. Hit the button multiple times to step through the speeds.
  • Within 5 seconds move your mouse over to the SPEED BUG knob and use your mouse wheel to increase or decrease the speed in the highlighted line
  • Click the SEL button again to move to the next speed.

Note - V1 and VR will be removed from the legend as soon as they are passed in the acceleration phase. They come back after touch down when the speed is decreased again. V2 will be removed when it runs of the speed tape and will also come back during the rollout.

The solid triangle represents the flap retraction speed (V FRI). Above this speed you can safely retract your flaps after takeoff.

The triangle outline is the climb speed (V Climb). After the level off (not below 400ft above the field) you can use it as a target when the one engine has failed.

Setting MDA Marker For Takeoff

It is quite helpful to set the Minimum Descent Altitude (MDA) marker to 1500ft above the airport elevation. Then we know when to reduce the pitch attitude after the takeoff and start accelerating into the climb phase. Read the current altimeter indication on the right side of the primary flight display (PFD) and add 1500ft, maybe round it up a little bit.

To enter this altitude as MDA

  • Rotate the outer knob of the DH/MDA selector left of the PFD to “MDA”. Right click the outer ring or use your scroll wheel on the mouse and scroll up (finger moving upwards)
  • Now use the inner knob to change the value of the MDA
  • Once you reach this altitude during the initial climb segment the MDA line on the altitude tape will turn blue, the “MDA” label on the attitude indicator will disappear.



MFD

EWD

Overhead Panel

Throttle Quadrant

The “throttle quadrant” in the Q400 moves a lot of levers into one location. From left to right the quadrant features:

  • ELEVATOR TRIM indication - If you don't have a control axis assigned for this you can use the mouse wheel over the indicator to adjust the trim ND (nose down) or NU (nose up). When you have an analog axis assigned please be ready to retrim the aircraft when ever you change the position of the aircraft with the location dialog. If you don't assign an axis the trim will be set for takeoff, landing or cruise depending when you select these starting locations with the location dialog.
  • EMERGency/Parking BRAKE lever - Click the lever to toggle the parking brake
  • POWER levers - currently cannot be adjusted by mouse but can be assigned in the control settings as “Throttle” 1 and 2 as well as “Thrust reverse” 1 and 2. The forward throttle controls the range from DISC to full RATING power with FLT IDLE being the minimum allowed position in flight. Reverse moves the levers aft of DISC towards FULL REV(erse).
  • CONTROL LOCK - click on the area of the power levers to set and remove the gust lock. This should only be done on ground as is locks the ailerons in neutral. When the power levers are advance to far the gust lock in Aerofly is automatically removed so that you can safely take off even if you forgot to remove the gust lock.
  • PROPeller levers - are also called “condition levers” since they not only affect the propeller rotation speed but also the rating of the engine (maximum torque value). These levers can be assigned in the control settings as “Propeller speed” 1 and 2 or can be adjusted with the mouse wheel and mouse buttons. When interacting with the mouse aim at the lower part of the lever, at the surface of the quadrant.
  • FLAPS lever - Affects the target position of the flaps. Flap 35 can only be recommended for very short runways, typically flaps 15 is plenty. The flap lever can be adjusted with the mouse scroll wheel and the left and right mouse buttons. There are also assignable axis or buttons for this lever in the control settings.

In the pedestal we find the Audio and Radio Control Display Units (ARCDU 1 and2), the aileron and rudder trim, the Multi Function Display (MFD) control panel and the Weather Radar controls.

ARCDU

The Audio and Radio Control Display Units (ARCDU 1 and ARCDU 2) are the Q400's interface to the navigation receiver frequencies and audio levels as well as the ATC/TCAS modes and microphone settings.

Automatic Frequency Tuning (FMS Mode)

The simulated ARCDU in the Aerofly FS 2 have the capability to tune the ILS frequencies of the destination airport fully automatically. They also set the course which is not possible in the real world aircraft. Automatic tuning is only performed when the mode selector of the ARCDU is in “FMS”. The left ARCDU (ARCDU 1) can tune ILS1 and the right ARCDU (ARCDU 2) tunes ILS2 if they are set to “FMS” mode respectively.

Manual Modes (ON, BOTH)

The left ARCDU (ARCDU 1) is assigned for the left side frequencies (VHF1, VOR1/ILS1 and ADF1). The right side controls all receivers with the number 2 at the end.

ON - Only editing of the the onside frequencies is allowed

BOTH - The frequencies of the left and right side can be tuned.

Manual Frequency Tuning

  • Set the mode switch to “BOTH” on the left and right ARCDU using the mouse wheel or left or right mouse button
  • Select the frequency that you want to edit with the line select keys on the side of the display by clicking on the button. Note - After 5 seconds the selection is reset and the highlight is no longer visible, press the line select key again
  • Use the fine and coarse knob to adjust the standby frequency, again using your mouse wheel
  • To transfer the frequency into the active field click the line select key a second time

Note - When FMS mode is selected or the mode selector isn't on BOTH and a frequency of the opposite side is selected with the line select buttons then the label will flash. Change the mode to BOTH on each ARCDU device to gain full authority.

ATC/TCAS

Transponder status

  • Right click the lower right line select key (next to ATC1 label) to toggle the transponder mode from OFF to ON ALT and back.

ATC/TCAS details

  • Left click the lower right line select key
  • Click the “EXP” button to visit the expanded ATC/TCAS page to see more options
  • Click individual line select keys multiple times to step through the displayed options
  • Press the “PG 1/2” mode to exit the expanded page

Note - Similarly you can access expanded pages for VHF1/2, NAV1/2 and ADF1/2. There is also a PG 1/2 button to access page 2 of the ARCDU.





Volume Levels

At the time this text was written no audio reception was implemented yet. So this is more in preparation for later.

  • Click the “PG 1/2” button to access the second page. Here you can monitor the volume levels for each receiver.
  • Use the scroll wheel of your mouse over the knobs on the lower part of the device to adjust the levels.
  • Click these knobs to activate or deactivate the audio reception of the individual channel














Engine And Prop Control Panel

There are several derates for the turboprop engines that the pilots of a Q400 can chose from. The selection is made with a movement of the PROP/condition levers and the available pushbuttons for engine control in front of the throttle quadrant. The available affect the maximum torque and therefor maximum power of the engines. We modeled all of the Q400 derates which are:

  • MTOP - Maximum TakeOff Power with 1020 RPM
  • NTOP - Normal TakeOff Power with 1020 RPM
  • RDC TOP TRQ - NTOP with additional Reduced Top Torque up to 10% decremented with 1020 RPM
  • MCL - Maximum CLimb Power with 900 or 850 RPM
  • MCR - Maximum CRuise Power with 900 or 850 RPM
  • - - - : no derate applicable (engine shut down)

When moving the condition levers the default selections are restored. The default engine derates are mapped to the lever position like this:

  • MAX 1020 - moving the lever to this position selects NTOP
  • 900 - selecting 900 RPM sets MCL
  • 850 - selects MCR
  • START & FEATHER - selects NTOP
  • CUT OTT - none

Engine Rating And Noise Reduction

After moving the condition levers to the desired rotation speed the default engine derate can be overwritten with the push buttons on the engine control panel:

  • With the PROP levers at MAX 1020 RPM you can click this button to set full 100% takeoff power
  • Click the MCL button to overwrite the default cruise power with climb power (MCL) when your PROP levers are at 850 RPM or 900 RPM. Is used in the real world for a noise reduced climb with 850 RPM and max climb power.
  • Click the MCR button to override the default climb power with cruise power (MCR) when your PROP levers are at 850 or 900 RPM. Is typically used when cruise altitude is reached and levers are already at 850 RPM due to a noise reduced climb.

Reduced Takeoff Power

To save fuel, engine wear and noise emissions a takeoff with reduced takeoff power can be performed.

  • Set the condition levers to MAX 1020 RPM
  • Click the “DEC” button on the RDC TOP section multiple times to decrease the maximum power rating for takeoff to a maximum of 10% torque reduction.
  • Click the reset button to reset normal takeoff power (NTOP)

Autofeather

  • Click the AUTOFEATHER button on the PROPELLER CONTROL panel to toggle the state of the automatic feathering in case of engine failure. At the time this tutorial was written auto feather was not not implemented.

Reduced Propeller Rotation Speed Landing For Noise Reduction

To reduce cabin and airport noise during the approach it is common to use a reduced rotation speed of 850 RPM. To be prepared for a go-around with full power available the aircraft is prepared as follows:

  • Move the PROP levers to 850 RPM if not already in that position from cruise and descent
  • Click the RDC NP LDG pushbutton
  • Move the PROP levers to MAX 1020 RPM and limit the power demand to below 50% within 15 seconds.

Note - To cancel this state either increase power above 50% to perform a go around or push the RDC NP LDG pushbutton a second time.

FGCP And Autopilot Modes

The Flight Guidance Control Panel (FGCP) is the interface to the autopilot and flight director. The left column of push buttons to the left of the vertical wheel in the center are used to change the vertical modes (pitch up and down). The buttons on right column affect the lateral steering mode (bank left or right).

In the center of the panel a vertical scroll wheel can be found that is used to manipulate the selected pitch, selected indicated airspeed or selected vertical speed, which ever mode is currently selected. The direction of the scroll wheel is always in the same manner, scroll the wheel up with the finger and you find the aircraft pitching down, rotating in a similar fashion as the wheel. And if the wheel is scrolled downwards the aircraft follows that rotation and pitches up.

In the lower left and lower right corner of the panel you can find the heading knobs (HDG). These knobs are rotated with the mouse wheel to change the selected heading. Use either heading knob, they are linked together in our simulated aircraft.

Brief explanation of the purpose of each knob:

  • COURSE - changes the selected course on either primary flight display (PFD). The knob has no effect when the navigation source is FMS1 or FMS2
  • NAV SOURCE - these knob changes the selected navigation source of the left and right PFDs respectively. Available sources are: FMS1, NAV1, NAV2, FMS2. Depending on weather the NAV1 or NAV2 frequencies are VOR or ILS frequencies the displayed sources are VOR1/ILS1 or VOR2/ILS2. To fly an ILS approach, with the ILS1 frequency set, the left NAV SOURCE knob has to be rotated to ILS1 and then the APPR button can to be pressed. To follow the lateral flight plan the source has to be selected to FMS1 or 2 and then the “NAV” button can be used to select LNAV
  • HDG - changes the selected heading on both PFDs. The selected heading is never synchronized in the Q400 and has to be re-adjusted manually.
  • ALT - increases or decreases the selected altitude. Note the arrow to the ALT SEL button as it is important to press ALT SEL whenever you plan to level off at the selected altitude!
  • Vertical Wheel - NOSE DN / NOSE UP. As mentioned above this changes the selected pitch, speed (IAS) or vertical sped.

Left buttons (vertical mode):

  • IAS - When pressed (left click) the vertical mode changes to Indicated AirSpeed mode (IAS). The current airspeed is used as a reference to pitch the aircraft up or down and therefor reduce or increase speed. The vertical wheel in the center can be used to change the selected IAS. Press again to return to PITCH HOLD.
  • VS - Changes the vertical mode to Vertical Speed hold (VS) when clicked. At engagement the current vertical speed is synchronized and can be changed using the vertical wheel. Depressing the button again changes the vertical mode back to PITCH HOLD.
  • VNAV - when the aircraft is in cruise and the selected altitude is lower than the current altitude this button may be clicked to arm the Vertical NAVigation. When the vertical profile, as observable left of the altitude tape on the PFD, is intercepted the armed VNAV engages to VNAV PATH. The mode can be disarmed or disengaged by pressing the VNAV button a second time. If it was engaged the vertical mode will revert to PITCH HOLD.
  • ALT - Commands an instant level off at the current ALTitude and changes the vertical mode to ALT (HOLD). The target altitude is the altitude at the time of engagement. The selected altitude is not taken into account. A second click on this button will restore the PITCH HOLD mode.
  • ALT SEL - This push button can be clicked with the left mouse button to arm the selected altitude. Any vertical mode (except glide slope) will be aborted and the active vertical mode changes over to ALT* (altitude acquire) followed by ALT (altitude hold) once the selected altitude has been reached. Clicking the button with the right mouse button simulates depressing the real world button for for one second. Then the ALT SEL is removed and the currently active vertical mode will not end in an altitude capture at the selected altitude. Note: When engaging a new vertical mode to fly towards the selected altitude the pilot has to press this button manually. Otherwise the aircraft will not capture the selected altitude and fly right through it. This is something that needs attention each time the selected altitude was changed (therefor the little line between ALT selector and ALT SEL pushbutton)

Right buttons (lateral mode):

  • HDG - A click on the heading button engages the heading select (HDG SEL) lateral mode. With the HDG SEL lateral mode engaged the flight guidance computer will command the autopilot to do a left or right turn to steer towards the selected heading value. The selected heading can be changed with the HDG knobs as described above. This HDG SEL mode mustn't be confuse with heading hold (HDG HOLD) where the heading at engagement is maintained and the selected heading is disregarded. A second click on the HDG pushbutton will cause the basic lateral mode to engage.
  • NAV - Depending on the the selected NAV SOURCE a press on this button will either engage LNAV HDG SEL (FMS1 or 2 selected) or arm VOR (NAV1 or 2 selected). When the heading intercepts the flight plan and the lateral deviation is small enough the LNAV HDG SEL will switch to LNAV and the aircraft will follow the lateral flight plan. When VOR is armed and the needle of the NAV1 or NAV2 receiver (depending on the selected nav-source) leaves the full deflection the VOR radial or localizer will be captured and maintained, even over the station. Modes VOR* and VOR OS are currently built into the VOR mode and not indicated separately as in real world.
  • APPR - Again, depending on the selected NAV SOURCE this buttons will do two things: either arm FMS APProach or ILS/VOR APPRoach. With FMS1 or 2 selected this button will arm the LNAV/VNAV APPRoach with similar capturing conditions to LNAV and VNAV, only ALT SEL will not cause a level off. This can be used to follow the flight plan all the way down to the runway threshold. But when NAV1 or NAV2 is selected as a navigation source the ILS approach will be armed (LOC + GS) or the just the localizer (LOC) when no glide slope is available.
  • BC - captures the localizer on the reciprocal course. This is not implemented yet.
  • STBY - Hides the flight directors and clears all modes when the autopilot is not engaged. Used to clear up the flight director and set it to standby. If the autopilot is connected this button will cause the vertical mode to revert to PITCH HOLD and the lateral mode to basic lateral mode.
  • AP - Autopilot master. Click this button to engage or disengage the autopilot. When the autopilot is set to on the yaw damper will also engage.
  • YD - Engages or disengages the Yaw Damper. As long as the autopilot is engaged this button is ineffective. When engaged the yaw damper reduces uncommanded yaw rates and stabilizes the fuselage longitudinal axis.
  • HSI SEL - Pressing this button selects either the left PFD or the right PFD for the autopilot source. When the arrow is pointing towards the left the pilot's navigation source is used for the autopilot. When the arrow points to the right the first officers navigation source is used instead. When both PFDs have NAV1 and NAV2 selected and NAV1 and 2 receivers are tuned to the same frequency and set to the same course and other conditions are met (e.g. DH left and right are identically and RA is below 1000ft) then both arrows will be illuminated at the same time and DUAL FD is indicated on both PFDs. In this configuration it is safe to fly an ILS Category 2 approach down to 100ft. The autopilot has to be disconnected prior to landing since the Q400 is not capable and not certified for a fully automatic landing.

Basic Lateral Mode

Whenever a lateral mode is disengaged by pressing the button a second time or when the STBY button is pressed or when the FD is engaging in flight the basic lateral mode engages. When the bank angle at that time is below ~6 degrees the wings are leveled (WING LVL) followed by a heading hold (HDG HOLD) and present heading is maintained. Above that threshold the current bank angle is maintained (ROLL HOLD). Tutch Control Steering (TCS) to manipulate this bank angle is not implemented yet.

Heading Select (HDG SEL)

  • Mouse over either the left or right heading knob (HDG) and use your scroll wheel up and down to change the selected heading right or left. The selected heading can be seen on either PFD or either MFD (given navigation display (ND) is displayed as per default)
  • Left click the “HDG” button once

Vertical Speed (VS)

  • Click the “VS” button
  • Use your mouse wheel over the vertical wheel to adjust the selected vertical

Indicated Airspeed Hold (IAS)

  • Click the “IAS” button
  • Rotate the vertical wheel to change the selected airspeed

Arming Altitude Acquire (ALT SEL)

Unlike most modern airlines the Q400 engineers decided that the altitude capture function should only engage when pilots explicitly press a button to arm it. Since it is very unique for an autopilot we modeled this in the Aerofly FS 2 aircraft but this also means that you have to check if ALT SEL is armed in white on the PFD every time you changed the selected altitude. Typically a press on the ALT SEL pushbutton is required when you are maintaining the current altitude and want to climb or descent to another altitude. Then another vertical mode has to be engaged and the selected altitude has to be changed and ALT SEL needs to be pushed.

On the upside, if you ever wish to prevent a level off you can disarm the altitude capture (ALT SEL) by holding the ALT SEL button for 1 second. In the Aerofly we currently model this with a right click due to technical reasons.

When ALT SEL is armed in white on the PFD the active vertical mode will change to ALT* (altitude acquire) to capture the altitude followed by ALT to maintain that altitude.

  • Use the scroll wheel of your mouse over the “ALT” knob on the autopilot panel. Select the initial altitude of the departure or even your cruise altitude. For our short tutorial flight from San Diego to Los Angeles select 15,000ft. This will be our cruise altitude.
  • Click the ALT SEL pushbutton on the autopilot panel to arm this selected altitude. If we don't do this the aircraft won't stop climbing.

There are four possible navigation sources in total: FMS1, NAV1, NAV2 and FMS2. The selected sources are changed with the NAV SOURCE knobs on the FGCP as well as the HSI SEL button on the same panel.

FMS1 and 2 are the flight management systems of the Q400 that contain the lateral and vertical flight plan.

NAV1 and NAV2 are navigation receivers that can be tuned to a certain frequency to receive VOR or ILS localizer signals as well as Glide Slope (GS) information and distance to the station with their distance measurement equipment (DME). Depending on the frequency NAV1 and NAV2 will be displayed as VOR1 or ILS1 and VOR2 or ILS2.

The selection of a navigation source is done individually on each of the two HSIs (left and right PFD). The flight guidance (autopilot) uses either the left or right side nav-source as indicated by the HSI SEL arrows on the autopilot panel (FGCP) as well as an arrow on the PFD not in use (pointing to the selected side).

  • Move the mouse over the left and right NAV SOURCE knob and rotate your mouse wheel to change navigation source of the left and right side PFD individually
  • Click HSI SEL to toggle between left and right PFD source

The currently selected navigation source for the HSI is displayed on the PFD, in a small legend next to the HSI. The selected course and course deviation change depending on the nav-source. The legend is colored in magenta for “FMS” navigation sources and cyan for “NAV” navigation sources. If the pilot and copilot both select the same navigation source the color for the nav source will be yellow, e.g. to warn both sides not to change any course or frequency without communicating with the other person.

Follow VOR/ILS (VOR, LOC + GS)

  • Leave the ARCDU mode in FMS for automatic ILS tuning OR switch it to BOTH and manipulate the NAV1 (or 2) frequency (usually left NAV1, right NAV2).
  • Set the course using the COURSE knob on the FGCP.
  • Rotate the NAV SOURCE knob on the FGCP with the mouse wheel until it displays the tuned ILS1 (or 2).
  • Press the APPR button on the FGCP to arm the LOC and GS, OR press the “NAV” button to follow just the localizer, lateral mode displayes as “VOR” in this case.


Lateral Navigation With Flight Plan (LNAV)

  • Rotate the NAV SOURCE with the mouse wheel until FMS1 or FMS2 are visible on your PFD in front of you.
  • Look at the HSI SEL arrow and press it, if necessary, to point in the direction of your PFD.
  • Click the “NAV” button

Note - If LNAV HDG SEL is indicating on the FMA turn the heading knob towards the route to get back on track. LNAV should engage automatically when the route is close enough and can be captured.


Climb And Descent Shedule

IAS Climb

Typically, during climb, IAS is used up to a certain altitude before switching back to PITCH HOLD. Three climb profiles can be chosen from:

  • High speed climb (Type 1): IAS 210 kts up to FL 150
  • Intermediate speed climb (Type 2): IAS 185 kts up to FL 200
  • Low speed climb (Type 3): IAS 160 kts up to FL 250

After that speed is either gradually reduced by about 5kts per 1000ft or the IAS mode is deselected by pressing the IAS pushbutton again. In the following PITCH HOLD mode the pitch attitude is lowered to about 5 degrees.

IAS Descent

During the descent either vertical speed, IAS or VNAV are used. It is also be possible to use PITCH HOLD during some phases in the descent.

For the descent the indicated airspeed mode (IAS) there are multiple descent types:

  • High speed descent (Type 1): IAS VMO - 10 kts (should be limited to -2000ft/min for cabin pressure differential)
  • Intermediate speed descent (Type 2): IAS ~200 kts
  • Low speed descent (Type 3): IAS 160 kts
  • and even more modes we won't go into here…

Vertical Navigation (VNAV) Descent

The vertical flight plan (VNAV) can only be used for the descent planning. The autopilot will fly a fixed geometric path towards the final approach fix and we have to manage the speed ourselves. We can reuse the speed profiles from the IAS descent (see above). Keeping the power lever a bit above FLT IDLE we can, for example, maintain around 240 kts which results in a nice and stable descent all the way into the approach without the need to reduce speed at any point in the descent.

  • For this select FMS1 or 2 as described above
  • Prior to the <TOD> on the map select a lower altitude than you are currently flying at
  • Press the ALT SEL to arm the altitude capture at the end of the descent.
  • Click the “VNAV” key on the FGCP. VNAV indicates in white on the flight mode annunciator (FMA) on the primary flight display (PFD) in the top right corner.

VNAV PATH will engage once the vertical profile is intercepted. To intercept use any other vertical, e.g. vertical speed and either increment the descent rate if you are above profile or reduce sinkrate or even level off when the vertical deviation shows that the flight plan is above you.

aircraft/dash8-q400_flight_deck.1501905805.txt.gz · Last modified: 2017/08/05 06:03 by jf