Brake to Vacate
| Company type | Software solution |
|---|---|
| Industry | Aviation safety, Avionics |
| Founded | 1998 |
| Founder | Fabrice Villaumé |
| Products | Runway overrun prevention and exit optimization software |
| Parent | Airbus |
Brake to Vacate (BTV) is a software solution created by Airbus for its airliner fleet, aiming to minimize runway overruns and enhance the accuracy of runway exits. Receiving certification from the European Aviation Safety Agency in 2009 for the Airbus A380, BTV contributes to improved safety and operational efficiency. Plans exist to implement the system on the popular Airbus A320 family, although with reduced capabilities due to the less sophisticated flight management systems on those aircraft.
Operation
The BTV system works in conjunction with the aircraft's auto-flight computer, allowing for programming of a predetermined stopping point and optimizing brake and thrust reverser usage accordingly.
On approach
During approach, BTV notifies pilots if the runway length is inadequate. An amber alert signals insufficient length under wet conditions, while a red RWY TOO SHORT warning accompanied by an audible alarm indicates critical runway length issues in dry conditions.
During rollout
After touchdown, BTV delivers visual and audio cues to ensure deceleration is maintained for a safe exit at the selected taxiway. If it detects a potential overrun, the system commands full wheel braking and maximum reverse thrust, displaying a red warning until the aircraft reaches a safe exit speed. BTV disengages automatically at 10 knots on 90-degree taxiways or between 40 and 50 knots on rapid-exit taxiways to facilitate efficient runway clearance.
Rejected takeoff
(To be announced)
Advantages
By accurately forecasting safe stopping distances based on inputs such as runway characteristics, aircraft mass, approach velocity, and surface conditions provided by pilots, BTV helps reduce brake and tire degradation by approximately 20%. It also shortens runway occupancy times and improves brake cooling predictions, thus aiding turnaround scheduling at gates.
Inputs
Pilots enter details about the intended runway and current surface conditions. The flight computer initially uses predicted speed and wind data for calculations until reaching 500 feet (150 m) altitude, after which it switches to actual speed and wind measurements.
Timeline
The concept of BTV originated from a 1998 doctoral dissertation by French engineer Fabrice Villaumé, who later headed Airbus’ BTV initiative and holds related patents. Between 2002 and 2006, software algorithms were developed with initial trials performed on an Airbus A340, including the first test landing in March 2005. The first A380 test landing utilizing BTV took place in May 2008.
Although Airbus planned to offer BTV as an optional feature on all A380s by 2007, delays in A380 production postponed these enhancements. Certification efforts for BTV on the A380 were underway by 2009, followed by announcements regarding its integration into other models. While retrofitting other families was suggested, by 2009 only plans for new installations on the A320 series had been disclosed without a definitive timeline.
In 2005, Airbus also aimed to incorporate BTV into the forthcoming A350; however, redesign phases delayed its confirmed availability. By 2018, the system was successfully integrated into the Airbus A350.