BTV

Question 1

What is the primary purpose of the BTV system?

Answer 1

To optimise aircraft braking for efficient runway exit and minimise brake wear.

Question 2

What are the three BTV modes?

Answer 2

1. Basic Mode (BRK MED): Constant deceleration until manually disengaged or the aircraft stops.
2. BTV Mode: Deceleration ramp to target value, maintains until disengaged or reaching 10 knots.
3. BTV CONTAM Mode: Constant deceleration on contaminated runways, ignoring exit position.

Question 3

When does BTV delay braking application?

Answer 3

On dry or wet runways, BTV delays braking if sufficient margins exist between the BTV stop bar and runway end, and aerodynamic or reverser deceleration exceeds the BTV deceleration profile.

Question 4

What must the flight crew do before arming BTV?

Answer 4

Insert applicable runway shifts in the ANF and crosscheck the displayed LDA with airport charts.

Question 5

How does BTV CONTAM differ from BTV Mode?

Answer 5

BTV CONTAM maintains constant deceleration from touchdown to 10 knots, regardless of exit position, to ensure safety on contaminated runways.

Question 6

What happens if a landing runway change occurs late in the approach?

Answer 6

BTV reverts to Basic Mode (BRK MED) if the runway mismatch is detected at 300 feet, and appropriate warnings are displayed.

Question 7

How should the flight crew manage a high-speed exit with BTV active?

Answer 7

Deactivate BTV when speed is appropriate for the exit (around 30 knots), stow reversers, and vacate the runway.

Question 8

What should the crew do if the selected exit is missed?

Answer 8

Deactivate BTV, manually manage braking, and taxi to the next appropriate runway exit.

Question 9

What is the impact of reverser thrust on BTV performance?

Answer 9

On wet runways, maximum reverser thrust improves exit accuracy. Using idle reverse may cause BTV to miss the selected exit.

Question 10

What should the crew do during overweight landings?

Answer 10

Use BTV to optimise braking by selecting an exit far down the runway to reduce speed gradually and minimise tyre deflation risk.

Question 11

What is the procedure for modifying the BTV exit during operations?

Answer 11

Select a new exit on the ANF, click SET BTV EXIT, and continue operations without disarming BTV.

Question 12

What causes a “Missed Exit” situation?

Answer 12

Long flare or excessive speed at touchdown.
Change in wind direction (headwind to tailwind).
Runway more slippery than a normal WET runway.
Use of REV IDLE on a WET runway.

Question 13

What does the BTV system do if a missed exit is confirmed?

Answer 13

Displays ‘EXIT MISSED’ on the FMA and increases braking application up to 0.35g for 5 seconds before requiring manual intervention.

Question 14

What must the flight crew ensure for BTV operation on a contaminated runway?

Answer 14

Select BTV CONTAM or BRK MED mode and, if necessary, apply manual braking to override BTV delays.

Question 15

What are the benefits of BTV on dry and wet runways?

Answer 15

Delays braking to maximise aerodynamic braking and reverser thrust efficiency.
Minimises brake energy usage and wear.
Reduces runway occupancy time by optimising deceleration for the selected exit.

Question 16

What does the flight crew do if the displayed LDA is incorrect?

Answer 16

Re-enter the correct runway shifts in the ANF and verify the updated LDA matches the airport chart.

Question 17

What is the significance of the “DECLUTTER RWY” function in BTV?

Answer 17

It simplifies the display by showing only interactive exit labels for the selected runway, reducing confusion when multiple exits overlap.

Question 18

How does BTV handle a runway condition change from DRY to WET?

Answer 18

Adjust the RWY COND/BRK ACTION selector to the appropriate setting (e.g., WET-5 or GOOD-5).
BTV remains armed, but the flight crew should reassess the selected exit, as TOO SHORT may appear on the ND.

Question 19

What should the flight crew do if the runway condition changes to contaminated late in the approach?

Answer 19

1. Use maximum reverse thrust immediately after touchdown.
2. Apply full pedal braking to override BTV if BTV CONTAM cannot be selected in time.
3. Perform a go-around if landing performance cannot meet the available landing distance.

Question 20

How does BTV optimise braking in overweight landings?

Answer 20

Targets reduced braking energy to avoid tyre deflation.
The flight crew should select exits farther down the runway or the runway end for gradual deceleration.

Question 21

What is the procedure if the ATC requests a late runway change?

Answer 21

1. If time allows, modify the FMS landing runway and BTV exit using the ANF.
2. If time is insufficient, BTV reverts to BRK MED mode upon landing.
3. ROW/ROP functions remain active for valid runways in the TAWS database.

Question 22

What considerations should the crew keep in mind when entering a high-speed exit with BTV active?

Answer 22

Ensure the exit is the one selected for BTV.
Deactivate BTV at an appropriate speed (~30 knots) before vacating the runway.
Manage the reversers and brakes to maintain smooth deceleration.

Question 23

How does BTV manage braking for a 90-degree runway exit?

Answer 23

Deactivates braking near 10 knots or upon manual disengagement.
The crew can deactivate BTV earlier if the exit geometry and surface conditions allow a safe turn above 10 knots.

Question 24

What happens if BTV detects an “EXIT MISSED” situation?

Answer 24

BTV increases braking force temporarily (up to 0.35g).
Displays ‘EXIT MISSED’ on the FMA and highlights the stop bar in amber.
The flight crew must deactivate BTV and manually manage braking.

Question 25

What factors can lead to a “Missed Exit” situation?

Answer 25

Excessive speed at touchdown due to long flare.
Runway slipperiness exceeding expectations (e.g., wet or contaminated).
Idle reverser thrust on wet runways.
Changes in wind conditions (e.g., headwind to tailwind).

Question 26

How should the crew manage braking if the selected exit is missed?

Answer 26

1. Deactivate BTV manually.
2. Taxi the aircraft to the next suitable exit.
3. Apply brakes manually to control deceleration.

Question 27

What should the crew do if multiple high-speed exits are displayed on the ANF?

Answer 27

Use the ‘DECLUTTER RWY’ function to display only interactive labels associated with the selected landing runway.

Question 28

How does BTV handle reverse thrust settings?

Answer 28

On dry runways, idle reverse thrust may suffice.
On wet or contaminated runways, maximum reverse thrust is recommended for optimal exit accuracy.