Descent Planning and Descent

This guide will explain the correct procedures to plan and fly a descent from cruise altitude through STAR and Instrument Approach up to the final approach.

The actual final approach (ILS approach) will be covered by a separate chapter.

Disclaimer

This is for simulation purposes only.

The level of detail in this guide is meant to get an Airbus A380 beginner safely from cruise level down to the ILS glideslope.

A beginner is defined as someone familiar with flying a GA aircraft or different types of airliners. Aviation terminology and know-how is a requirement to fly any airliner even, in Microsoft Flight Simulator.

Prerequisites

Aircraft is in CRUISE state and phase as per previous chapters

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Chapters / Phases

This guide will cover these phases:

Descent and Approach Planning
Starting the Descent
Flying the STAR and Approach
Intercepting ILS

Base Knowledge: Route, Star, Approach and ILS

Basics Information

As we have learned in previous chapters, a flight route begins with an origin airport and a SID to safely guide the aircraft away from the airport to the first waypoint on their actual route. Similar to a SID, the arrival to an airport is done via a STAR (Standard Terminal Arrival Route) and an IAP (Instrument Approach, often APPR) to safely bring the aircraft into a position to land on the destination airport safely and with as little ATC communication as possible.

Standard Terminal Arrival Route (STAR)

STAR

A Standard Terminal Arrival Route (STAR) ensures safe and efficient traffic from the last en-route waypoint to the initial approach fix (IAF) of the Instrument Approach (IAP). It separates aircraft, avoids conflicts and helps with noise abatement through specific routing, levels/altitudes, speed restrictions and checkpoints often with holding areas.

One main objective is, to do this with a minimum of communication between the ATC controller and the pilot. As the STAR is part of the flight plan, a pilot can simply continue from the normal route into the STAR if ATC has not given any other instructions. Sometimes ATC might give an explicit clearance for the STAR or change the STAR to manage traffic and landing situation (different runways, etc.).

Often a STAR contains a clearance point which mustn't be passed without explicit clearance by ATC. If clearance is not given, then a holding must be flown as described in the charts.

Please also have a look at our airliner guide's SIDs and STAR section SIDs and STARS

Find a good overview over charts in our airliner guide: Reading a Chart

Instrument Approach (IAP)

Instrument Approach

The Instrument Approach (IAP or APPR) has similar goals as a SID or STAR - safely bring an aircraft into a position to land while ensuring separation between multiple aircraft, avoiding terrain, support with noise abatement, etc.

IAP are often designed for handling maximum traffic in even bad weather conditions. With only little traffic and good weather, it is quite common that ATC instructs the pilot to leave the approach route by giving the pilot heading vectors for a more direct route to the Final Approach Fix (FAF, also called final approach point).

When flying with Online ATC (VATSIM, IVAO, PilotEdge, ...) expect being vectored to the FAF quite often.

Understand important ILS approach chart features here: Approach Chart

Instrument Landing System (ILS)

The Instrument Landing System (ILS) is one of several modern forms of helping an aircraft during its final approach to land even in non-optimal weather situations. ILS uses a localizer for lateral guidance and a glideslope for vertical guidance from the Final Approach Fix down to a minimum at which the pilot needs to perform the final landing sequence visually.

Modern airliner like the A380 are even able to use the ILS to land fully automatically as long as the runway's ILS supports it.

Understand important ILS approach chart features here: Approach Chart

Microsoft Flight Simulator and navigation charts

Although Microsoft Flight Simulator allows some flight planning through the user interface, it is highly recommended to use navigational charts when flying airliners. MSFS' flight planning does not provide sufficient information to correctly fly a STAR or an approach.

There are several good sources for charts - free or subscription based. A good free solution is ChartFox, which only requires a free VATSIM account. One of the most known subscription-based sources for charts is Navigraph. Navigraph has been integrated into the FlyByWire A380X flyPad, whereas Chartfox is TBD.

Also, often a simple internet search will do the trick: Search for "<airport icao code> charts": E.g., "EDDM charts"

1. Planning the Descent and Approach

Situation:

Aircraft is in CRUISE state and phase as per previous chapters.
Distance to destination is ~200NM (on a short flight, start as early as possible and maybe even before the flight).

Pilot's responsibility

It is the sole responsibility of the pilot to conduct proper flight planning, and especially proper descent planning.

It is not at all ATC's task to do descent planning for pilots by giving descent instructions. On the other hand, ATC often actually gives descent instructions, especially on common routes, as they want the aircraft in their responsibility to be at certain altitudes when approaching the destination airport. Nevertheless, pilots must know when approaching their top of descent and if necessary need to proactively request clearance to descend from ATC.

Good descent and approach planning is the foundation for a successful landing. It has to be done early during the flight or even before the flight.

Important Data Points for Descent Planning:

Cruise Flight Level: The higher we fly, the earlier we need to start descending. Also for short flights, too high a cruising altitude can make it impossible to actually descend to the destination airport in time. Therefore, verify your flight plan if overall distance and flight level make sense.
Flight Plan Constraints: STARs often have flight level (FL) or altitude constraints which we must adhere to. We must plan our descent, so we can meet these altitude constraints, even when they themselves are still far away from the destination airport.
Speed: STARs also regularly have speed constraints which we need to take into consideration as slowing down will cost time and is hard to do while descending. If we start our descent too late, we might not be able to slow down in time as required by a constraint.
Aircraft capability and passenger comfort: Although not a big concern in the A380, general aircraft capabilities and passenger comfort also come into play.

Step-by-step Guide for Descent Planning

Read the STAR chart and determine if there are altitude and/or speed constraints which we need to consider.
Consider the STAR and APPR route as optional and do not count on them to be flown and available for descending. ATC might want to vector us to a different runway or at least shortcut our approach. But they won't be able to if we are still too high for the final approach.
Determine the first constraint you need to meet. This could be a STAR waypoint with an altitude constraint, the Final Approach Fix altitude or even the airport (or runway) elevation itself.
Calculate the required distance needed to descend to that waypoint with a standard descent angle of 3°. We can use the FlyByWire flyPad in the cockpit or a simple rule of thumb calculation (details below).
Use the DIR TO function of the F-PLN page to determine the distance to the waypoint (see details below).

How to Calculate the Required Distance for Descent

Calculate the Required Distance for Descent

Example data:

Flight to EGKK via STAR TEBRA 2G.
Flight level FL320.
STAR constraint at waypoint ABTUM "at FL140".

Example chart:

_{Copyright © 2021 Navigraph / Jeppesen

"Navigraph Charts are intended for flight simulation use only, not for navigational use."}

Using the flyPad:

Standard calculation with 3° descent path:

Calculation with a specific distance to calculate the required descent velocity (V/S):

Rule of Thumb

Distance = "Altitude difference"*3/1000+margin**

Altitude difference: 32000-14000=18000
Times 3:             18000*3=54000
Divided by 1000:     54000/1000=54
Plus margin (~10%):  59NM

The margin can be lower for headwind and larger for tailwind. Some pilots also change the margin to compensate for slowing down while descending.

As can be seen on the chart, there will be a further descent to TIMBA at FL70 and after that (not visible on the
chart above), there will be a descent to the final approach which will be at 2000ft at the Final Approach Fix FF26L.

The same methodology/calculation as our initial descent can be applied to these descents as well, but they require less planning as they are usually designed in a way that an aircraft with a 3° descent angle can make these descents with ease.

ATC will quite often instruct certain altitudes within the STAR and APPR which deviate from the STAR and APPR charts. Please expect such instructions at any time.

Distance to Waypoint

The F-PLN page of the MFD has the DIR TO function which can be used to determine the distance to a waypoint. This is currently the only way to get this information without having to calculate it manually by adding up all distances between waypoints as displayed on the F-PLN page.

Unfortunately, the A380X does not yet have FIX INFO implemented, so we can't use it to determine when to start descent at a certain distance.

To use the DIR TO function, go to the F-PLN page and select the waypoint you want to know the distance to. Then press on the waypoint and select the DIR TO option in the popup menu.

ND distance rings:

The ND distance rings can also be used to determine the distance to a waypoint or fix. The distance rings can be set to a specific distance and will show the distance to the waypoint or fix. The distance rings can be set by pressing the ND button on the lower ECAM display and then selecting the distance rings option.

TODO: update screenshot for A380X

Arrival Planning

For arrival planning, we can collect the following information and execute the following steps:

Entering DEST DATA on the MFD

Before we descend, we should also reconfirm our destination runway and input or update our destination data into the MFD PERF APPR page. This is typically done about 50NM before the starting the descent. We can obtain this data from the destination airport's ATIS information and the airport charts.

From ATIS we get: QNH, TEMP, MAG WIND and TRANS LVL - if not refer to the approach chart.

ATIS Example:

ARR-ATIS EDDF P METAR 1450 - EXPECT DEPENDENT PARALLEL ILS Y
APCH RWY 07L OR ILS APCH RWY 07R - RWY 07L 07R - EXPECT RADAR
VECTORING, GLS APCH ON REQUEST, DO NOT MISTAKE TWY M FOR RWY 07C
WHEN PERFORMING VISUAL APPROACH - TRL 60 - 32003KT 270V350 -
9999 - - - FEW038 - T19 DP08 - QNH1030 - NOSIG -

From the chart, we get Trans level and BARO (=DA or MDA) or RADIO (=RA or DH).

CAT I ILS uses DA or MDA and is entered into the BARO field.
CAT II/III ILS use RA or DH, which is put in the RADIO field.
BARO is based on barometric altitude whereas RADIO is based on radio altitude (distance to ground).

For more information on the different types of minimums, see the Minimums and MDA/DH section on the Approaches page in the airliner flying guide.

Trans level: By ATC

In the particular example below, the Trans level field states By ATC. If you are not flying on a network such as VATSIM or IVAO, you can try the following things:

Search online for the real life D-ATIS at your arrival airport (much like the ATIS example above).
Use the Trans ALT+1000ft.
If you have imported your flight plan via our simBrief integration, this value would be autopopulated for you.

ILS in the A380

Although the A380 is capable of a CAT IIIB ILS approach (with Autoland) and has an approach category of "C" we will do a manual landing for the purpose of this guide. (see Wikipedia Aircraft approach category)

So for the minimums we need to find the DA or MDA for CAT I ILS for the destination airport. In this chart for EDDF 07C ILS there is a DA of 528ft defined - so we can enter "528" into the BARO field.

If we are using Microsoft Flight Simulator without any Online ATC services (VATSIM, IVAO, PilotEdge, ...), and using the MSFS built-in ATC, you usually can't request ATIS information for the destination airport at this point. MSFS ATC makes ATIS only available once close to the destination airport.

If we are flying with Online ATC, you can request ATIS via the network.

METAR Information

We can in any case request the METAR weather information the flyPad EFB.

WEATHER AND LANDING INFORMATION ................................... OBTAIN
LANDING ELEVATION .................................................. CHECK
BAROMETRIC REFERENCE .............................................. PRESET
LANDING PERFORMANCE ................................................ CHECK

Landing Performance

Unfortunately, there is no landing performance calculator for the A380X yet. This will be added in the future.

Flight Management System (FMS) Checks

If not already inserted, insert the applicable APPR, STAR, TRANS and APPR VIA in the active flight plan arrival page of the flight management system.

FMS ACTIVE/F-PLN/ARRIVAL PAGE ............................... INSERT/CHECK
DES PANEL OF THE FMS ACTIVE/PERF PAGE ....................... INSERT/CHECK
APPR PANEL OF THE FMS ACTIVE/PERF PAGE ...................... INSERT/CHECK
GA PANEL OF THE FMS ACTIVE/PERF PAGE ............................... CHECK
FMS POSITIONAL/NAVAIDS PAGE ........................................ CHECK
FMS ........................................................... CROSSCHECK

If available, you can also set up the OANS and BTV for the destination airport.

OANS

The Onboard Airport Navigation System (OANS), developed jointly by Thales and Airbus, is a groundbreaking technology designed to enhance pilot navigation during airport operations.

Key features of OANS include:

Overview Map Display: OANS provides pilots with an overview map display of the airport apron and taxiways. This display indicates the precise location of the aircraft on the map, aiding pilots during taxiing and ground movements.

Geo-Referenced Map Integration: The system integrates the plane’s position on a high-resolution, geo-referenced map using a standardized Airport Mapping Database. This ensures accurate and clear navigation guidance for pilots, especially when they find themselves in unfamiliar airports after landing.

Efficiency Benefits: By helping pilots navigate airports more efficiently, OANS aims to: - Reduce taxi time. - Streamline airport handling operations. - Maximize turnaround times

Adaptation to Multiple Platforms: Initially certified for the A380, OANS has been adapted to other Airbus platforms, including the A320, A330, A340, and A350 XWB. Thales’s expertise allows effective adaptation of systems designed for newer platforms into earlier ones3.

In summary, OANS bridges the technological gap between the air and the ground, providing pilots with clear and concise directions from landing through arrival at the gate, and vice versa3.

BTV

Brake to Vacate (BTV) is a system that helps pilots to select the most appropriate runway exit for their aircraft based on the aircraft’s current position, speed, and weight. The system calculates the optimal exit based on the aircraft’s deceleration capabilities and the distance to the exit.

By selecting the most appropriate exit, pilots can reduce taxi times and improve airport efficiency. This is especially important for busy airports with high traffic volumes, where every minute saved can help to reduce congestion and improve overall airport operations.

BTV is a valuable tool for pilots, providing them with the information they need to make informed decisions about runway exits. By selecting the most appropriate exit, pilots can help to reduce taxi times, improve airport efficiency, and enhance the overall passenger experience.

RUNWAY SHIFT ................................................. AS REQUIRED
ND MODE ............................................................. PLAN
ND RANGE ............................................................ ZOOM
RUNWAY ............................................................ SELECT
RUNWAY EXIT ....................................................... SELECT

Exit Selection

It is recommended to select the exit in accordance with the runway conditions. It is recommended to select an exit after the wet line to anticipate any changes of runway condition, as well as a smoother deceleration for passenger comfort. It is also recommended to take into account arrival gate, the ground circulation, the runway exit configuration, and the predicted turn around time, which is displayed on the navigation display

AUTO BRAKE/BTV ....................................... SELECT, AS REQUIRED

Brake / BTV

It is recommended to use of the autobrake system to have equal brake pressure and prevent brake overheat. Select the appropriate autobrake mode, depending on the weight, the runway length, the conditions and the winds. However, if the pilot selects the BTV system, set the BTV mode before removing the onboard airport navigation display from the navigation display. It is recommended on contaminated runway to use the autobrake mode 3. It is recommended to use of the HI mode if the BTV mode is not available or on short runway conditions

OANS RUNWAY LENGTH VS CHARTS RUNWAY LENGTH .................... CROSSCHECK

See our OANS Guide for more information on the system.

LANDING BRIEFING ................................................. PERFORM

This concludes Descent and Approach Planning.

2. Descent

Situation:

Aircraft is in CRUISE phase as per previous chapters.
Descent and approach planning is done.
The first descent point (altitude at certain waypoint) is identified.
Distance-to-descent point is calculated, which is called TOD (top of descent).

Descent Clearance from ATC & TOD

A few minutes before we reach our calculated descent point (TOD) we request clearance for descent from ATC if not already given a descent instruction before.

Do NOT start the descent without clearance from ATC.

The A380 has a downward pointing arrow at the TOD to support the pilot with the decision of when to descend.

Ultimately, it is still the pilot's responsibility to calculate and validate the TOD.

When clearance is given, we can start our descent to the flight level or altitude ATC has given us.

DESCENT CLEARANCE ................................................. OBTAIN
CLEARED ALTITUDE ON AUTO FLIGHT SYSTEM CONTROL PANEL ................. SET
ANIT-ICE ..................................................... AS REQUIRED

Starting the Descent

DESCENT ......................................................... INITIATE
ALTITUDE ..................................................... QNH/HPA SET
CABIN CREW ........................................................ ADVISE

How to initiate the descent

For descending, we set the new flight level or altitude in the FCU with the altitude selector. We can then either PUSH the selector for Managed Altitude Mode (constraints are respected, also known as DES) or PULL the selector for Selected Altitude Mode (constraints are ignored, also known as OP DES).

What is DES mode

Managed Descent (DES) Mode will follow a calculated vertical profile, this may lead to unexpected occurrences of very high and very low V/S. Users not familiar with Airbus Managed Descent should use OP DES instead as it provides a linear descent most users would expect.

See the Vertical Guidance Guide for more information on using managed vertical modes.

When either of these altitude modes are engaged, the relevant mode will appear in the Second Column of the FMA, and will be displayed in green.
(See A32NX Vertical Mode Annunciations as the A380 FMA is very similar).

Using V/S not recommended for beginners

It is not recommended to use V/S for climbing or descending in the A380 (at least not for beginners) as the V/S guidance has priority over the speed guidance, and speed needs to be watched very closely when using V/S.

If the selected target V/S is too high (relative to the current thrust condition and speed), the FMGC will steer the aircraft to the target V/S, but the aircraft will also accelerate or decelerate. When the speed reaches its authorized limit, V/S automatically decreases to maintain the minimum or maximum speed limit.

See also A32NX Protections as the A380 systems are very similar.

VNAV and ATC in the FlyByWire A380X

In case we are cleared to a lower altitude or flight level with altitude constraints above the clearance is an ideal scenario for the called so VNAV autopilot mode, which would be activated by using "Managed Altitude Mode" (pushing the ALT selector).

The autopilot will automatically level off at the constraint and continue descending when the constraint is no longer valid. ATC typically will not clear us to our final target altitude directly, but will give us several step descents down to our required altitude.

ATC will often still expect us to respect the STAR's constraints, although they might have given us a lower clearance. We should then only descent to the constraint's altitude. We repeat the process until we have reached our desired final approach altitude.

DESCENT .......................................................... MONITOR
RATE OF DESCENT ....................................... ADJUST AS REQUIRED
SPEEDBRAKES .................................................. AS REQUIRED

Airline SOPs

Some airline's SOPs (standard operating procedures) might have a different order for the following steps.

At 20,000 feet

CABIN CREW ........................................................ ADVICE
TERRAIN RADAR ................................................ AS REQUIRED
WEATHER RADAR ................................................ AS REQUIRED

Weather Radar

The Weather Radar is currently not available in the A380X. It is planned to be implemented in the future if and when the simulator provides the required weather data.

At 10,000 feet

What and Why?

As we reach the 10,000 foot mark in our descent, we have to take a few more steps to prepare the aircraft to land. We make sure the seatbelt sign is on so passengers are secure and not moving around during descent. We also make sure the landing lights are on so we are visible to other aircraft on approach.

The LS buttons are turned on so we have the landing system active for when we intercept the ILS.

LANDING LIGHTS ........................................................ ON
LANDING DATA ......................................................... SET
SEAT BELTS SIGN ....................................................... ON
CSTR BUTTON ........................................................... ON
LS BUTTON .................................................... AS REQUIRED
NAVAIDS ................................................ AS REQUIRED/CHECK

How and Where?

Flight Deck Overview

Use the Flight Deck Overview to locate the items mentioned above. The Flight Deck Overview is a clickable cockpit that will show you where each item is located.

APPROACH CHECKLIST .............................................. COMPLETE

Approach Checklist

The Airbus A380 has a built-in checklist system that can be accessed via the Engine Warning Display (EWD).

To activate it you need to press the C/L button on the ECAM Control Panel (ECP).

You can navigate through the checklist by using the UP and DOWN buttons on the ECP. You can check/uncheck items by pressing the buttons with the check mark on the ECP.

Some items are autosensed by the aircraft and will be checked automatically (e.g. Beacon).

Cabin Crew in real life

In real life, the cabin crew will be asked to prepare the cabin for landing at some point during the descent. The exact moment and process might differ between airlines, but most seem to do this when the Seatbelt Signs are turned on (typically at the latest at 10,000ft).

The Cabin Crew will notify the pilots either by a "Cabin Ready" button (A380) or by a call to the cockpit once they are ready and strapped in themselves. Typically, we will be in final approach by that time.

This concludes Starting the Descent.

3. Flying the STAR and Approach

Situation:

Aircraft is in DES phase.
Descent has started (we are after TOD).
We have not yet reached the first waypoint of the STAR.
FMS PERF APPR page is filled - see Arrival Planning).

Flying the STAR and Approach is very similar to any other part of the route within the flight plan. Apart from descending and adhering to constraints, the lateral flight path just follows the programmed route.

Let the Autopilot do this for you, and just adjust altitude and speed according to the charts or ATC instructions.

ATC Instructions During STAR and Approach

At some point during the descent and when close enough to the airport, we will be instructed by ATC to contact ATC Approach for the airport we are flying into.

Be prepared for ATC instructions to deviate from the STAR or Approach route to separate from other aircraft or to shortcut the approach when there is little traffic. ATC will then typically give you new heading instructions (heading vectors) and will guide you the rest of the STAR and Approach with additional heading instructions until intercepting the ILS localizer.

Example for shortcuts:

DEBHI1D STAR EDDF (Frankfurt) 07C - it is only in times with a lot of traffic that we would have to fly the whole downwind part of this transition.

Note: If you do fly without Online ATC use DIR TO to the IAF waypoint DF554 after DF644 to start the final approach and intercept the ILS localizer.

4. Intercepting ILS

Situation:

Aircraft is in DES phase.
Aircraft is set up for flight <10,000ft (seat belt signs on, landing lights on, etc.).
We are either within the IAP (Instrument Approach) and at the correct altitude and speed or at a heading vector, altitude, and speed instructed by ATC.

Reaching the beginning of the ILS Approach

At the start of the Instrument Approach (or by ATC vectoring) we will be on a path to the Final Approach Fix and/or intercepting the ILS localizer and eventually the ILS glideslope.

To intercept the ILS, we need to be at the correct altitude and should not have an approach angle larger than 30°. The LS button should also be ONon both the captain and first officer's sides of the FCU.

APPROACH PHASE ............................................ CHECK/ACTIVATE

Approach Phase

The FMS approach phase activates:

Manually, when the flight crew clicks on the ACTIVATE APPR on the FMS PERF page, or
Automatically, when NAV is engaged, and the aircraft flies the DECEL pseudo waypoint.

MANAGED SPEED ...................................................... CHECK

Managed Speed

It is recommended to regularly verify the managed speed and to monitor the target speed.

When in NAV, LOC*, or LOC mode is engaged, the aircraft will automatically decelerate at the DECEL waypoint.

SPEEDBRAKES .................................................. AS REQUIRED

More details regarding the ILS approach and landing in the next chapter.

This concludes Intercepting ILS.

Continue with Final Approach and Landing

Descent Planning and Descent

Prerequisites

Chapters / Phases

Base Knowledge: Route, Star, Approach and ILS

Basics Information

STAR

Instrument Approach

Instrument Landing System (ILS)

1. Planning the Descent and Approach

Pilot's responsibility

Step-by-step Guide for Descent Planning

Calculate the Required Distance for Descent

Rule of Thumb

Distance to Waypoint

Arrival Planning

Entering DEST DATA on the MFD

Trans level: By ATC

ILS in the A380

METAR Information

Flight Management System (FMS) Checks

OANS (Onboard Airport Navigation System) and BTV (Brake to Vacate)

2. Descent

Starting the Descent

At 20,000 feet

At 10,000 feet

3. Flying the STAR and Approach

4. Intercepting ILS