The graph showing the accident distribution by flight phase from the “A Statistical Analysis of Commercial Aircraft Accidents 1958-2024” website clearly indicates that the majority of commercial aircraft accidents in the last twenty years (59 %) occurred during the landing phase (fig.1).

The website also highlights that runway excursion was the third main cause of commercial jet fatal accidents and the first main cause of hull losses in the last twenty years (fig.2).

(fig.2) Accident distribution per category 2004-2024

In the early 2000s, Airbus initiated the development of a new technology to mitigate the risk of runway excursion: The Runway Overrun Prevention System (ROPS).

ROPS has two sub-functions that are activated one after the other, during the final approach and landing phases.

ROW is active during the final approach until touchdown. This is called the air phase. The system continuously computes the landing distance of the aircraft in real-time, comparing it with either the Landing Distance Available (LDA) of the runway or the remaining runway length, if the aircraft has already crossed the runway threshold.

Below 400 ft, if a runway overrun risk is detected, ROW alerts the flight crew, enabling them to decide to either continue the landing or perform a go-around.

After touchdown, during the on-ground phase, ROP monitors the position of the aircraft relative to the remaining runway length and continuously computes the stopping distance needed by the aircraft based on current aircraft speed and deceleration.

If a runway overrun risk is identified, ROP alerts the flight crew asking them to apply and keep all available deceleration means i.e. maximum braking and maximum reverse thrust. ROP remains active until 30 kt (taxi speed) is reached.

(fig.3) ROPS concept

Airbus continuously enhanced the ROPS concept taking into account in-service feedback from the operators. It evolved from Step 1 on the A380 only, to Step 2 and Step2+ also available on A320 family and A330 aircraft, to now reach Step 3, available on A350 aircraft, and progressively made available for the A320 family aircraft.

The reduction in runway overruns encountered by Airbus aircraft in the last 20 years shows a positive trend. The combination of several industry initiatives to prevent runway overrun combined with the progressive implementation of ROPS on the Airbus fleet undoubtedly contributed to these encouraging results.

The initial concept (ROPS step 1) was introduced on A380 aircraft in 2009. ROPS Step 1 was only available when an autobrake mode was selected (LO, 2, 3, HI or BTV) and was available only for dry and wet runways. ROPS Step 1 is no longer available since all A380 aircraft were upgraded to Step 2.

ROPS Step 2 has the same functionalities as Step 1, but is available both in autobrake and manual braking modes. ROPS Step 2 was introduced in 2011 on A380 aircraft. It also became certified for A320 family and A330 aircraft, respectively, in 2012 and 2013.

ROPS Step 2 continuously computes and compares the landing distance for both dry and wet runway states: 

• If the computed landing distance for a WET runway is greater than the LDA (fig.5), the PFD displays an IF WET : RUNWAY TOO SHORT alert. 
• If the computed landing distance for a DRY runway is greater than the LDA (fig.6):
  • Between 400 ft and 200 ft, the PFD displays a RUNWAY TOO SHORT alert. 
  • Below 200 ft, the PFD still displays a RUNWAY TOO SHORT alert and adds a “RUNWAY TOO SHORT!” audio alert.

Step 2 uses the WET stopping distance to trigger ROP alerts. If a risk of runway overrun is detected, the following occurs:

• The PFD displays MAX BRAKING MAX REVERSE red messages.
• Simultaneously, a “BRAKE! MAX BRAKING! MAX BRAKING!” audio alert is triggered and is repeated until full pedal braking is detected.
• Then, if full pedal braking is detected but thrust levers are not detected in the MAX reverse position, a “SET MAX REVERSE!” audio alert is triggered and is repeated until MAX reverse is detected.
• At 80 kt, if the risk of overrun is still detected, a “KEEP MAX REVERSE” audio message is triggered to prevent the flight crew from selecting REV IDLE at 70 kt.

On A380 aircraft, if an autobrake mode is engaged, ROPS automatically applies maximum braking if a risk of overrun is detected. In that case, the MAX BRAKING message is not displayed on the PFD and its audio alert is inhibited.

(fig.5) ROPS Step 2 alerts when the computed landing distance for a WET runway is greater than the LDA

(fig.6) ROPS Step 2 alerts when the computed landing distance for a DRY runway is greater than the LDA

ROPS Step 2+ was introduced on A350 aircraft in 2014, and on A320 family and A330 aircraft in 2020.

ROPS Step 2+ introduces a ROW/ROP runway condition selector (fig.7) that should be used during the descent preparation to select either the WET or DRY runway condition. The selected runway condition is displayed at the top of the ND.

Unlike ROPS Step 2, the runway condition selector of ROPS Step 2+ enables the function to filter alerts, displaying only the one relevant to the selected runway condition, therefore, removing the “IF WET : RUNWAY TOO SHORT” conditional alert.

When either DRY or WET is selected:

• Below 400 ft, if the computed landing distance of the selected runway condition is greater than the LDA, then the PFD and HUD (if installed) display an amber “RUNWAY TOO SHORT” message.
• Below 200ft, if the computed landing distance of the selected runway condition is greater than the LDA, then the PFD and HUD (if installed) display a red “RUNWAY TOO SHORT” message combined with a ”RUNWAY TOO SHORT!” audio alert 

Step 2+ ROP offers similar but enhanced alerts compared with Step 1 and Step 2 alerts. This enhancement comes from Step 2+ using the specific stopping distance for the runway state chosen on the runway condition selector, rather than the more conservative WET value used by ROPS Step 1 and Step 2 (fig.9).

ROPS Step2+ also introduces a dedicated ROW/ROP pushbutton-switch on the overhead panel to manually inhibit the ROPS function (fig.8).

Airbus demonstrated that the ROPS Step2+ is compliant with the ROAAS mandate.

(fig.9) ROPS Step 2+ alerts

ROPS Step 3 was first introduced on the A350 in 2016, and is progressively being certified for the different aircraft models of the A320 family, starting with the A321XLR in 2024. It is available for all runway conditions. ROPS Step 3 represents a significant safety benefit for airlines operating on airports subjected to snow, icing, or heavy precipitation conditions or airports with shorter runways.

ROPS Step 3 requests the flight crew to select the runway conditions or reporting braking action among the 6 levels defined in accordance with the Global Reporting Format (GRF) from ICAO.

On A350 aircraft, the flight crew can select the runway condition using the RWY COND / BRAKING ACTION selector on the brake panel (fig.10). The selected value is displayed in the _RWY CONDITION / BRAKING ACTION_ matrix displayed on the SD. A barber pole indicates the runway conditions where a risk of overrun is detected.

On A320 family aircraft, the flight crew can select the runway condition on the _RWY COND FOR ROW/ROP_ page accessible from the _PERF APPR_ page of the MCDU.

(fig.10) Selection of the runway state for ROPS Step 3

Step 3 provides similar ROW and ROP alerts to the Step 2+ alerts, but for the selected runway condition, with some enhancements.
On A350 aircraft, if an autobrake mode is engaged, ROP automatically applies maximum braking if a risk of overrun is detected. In that case, the MAX BRAKING message is not displayed on the PFD and its audio alert is inhibited.

A pre-ROP function provides the crew with a single ‘SET MAX REVERSE’ audio message, acting as a Standard Operating Procedure (SOP) reminder to select maximum reverser thrust in the following conditions:

• The selected runway condition is different from DRY
• MAX REV is not selected after touchdown
• The computed stop distance is still on the runway but near the end of the runway. 

On the ground, if the braking efficiency is lower than anticipated for the selected runway condition, ROP can automatically downgrade the runway condition to the current one. 

The RCDF provides awareness of the downgrading via a message on the FMA (fig.11), as well as an update of the runway condition indication on the ND.

On A320 family aircraft, ROPS Step 3 is not equipped with a  ROW/ROP deactivation pushbutton-switch. It can be manually deactivated via the MCDU _SURV CONTROLS_ page, accessible via the _DATA INDEX_ page.

Airbus demonstrated that ROPS Step 3 is compliant with the ROAAS mandate.

(fig.12) ROPS Step 3 alerts

A ROAAS function is also being developed for A220 aircraft. It is not yet certified at the time of publication of this article.
The A220 ROAAS slightly differs from the ROPS installed on the other Airbus aircraft, but the same principle applies.

The flight crew can select the runway condition from the MFD PERF page.
The DRY, WET, and WET GROOVED will be available at the introduction of the ROAAS. The other runway conditions will be available after additional certification. 

As for ROPS, the A220 ROAAS is composed of an air phase divided into two parts by an altitude threshold and an on-ground phase requesting the use of all the deceleration means in the case of a risk of overrun.

(fig.13) A220 ROAAS function

All A380 aircraft are equipped with ROPS Step 2 and all A350 aircraft are fitted with ROPS Step 3. 

On A320 family and A330 aircraft, various ROPS standards are currently in service. This can lead to operators having fleets with mixed ROPS standards. However, this is manageable as the operational differences between standards are minor and easily recognizable.

During the cockpit preparation, the flight crew can check if ROPS is installed on their aircraft using the Aircraft Configuration Summary table of the QRH.

No action related to ROPS is required for aircraft equipped with Step 2. 

On aircraft equipped with ROPS Step 2+, the flight crew should use the ROW/ROP runway condition selector to select the DRY or WET condition depending on the reported conditions.

On A320 aircraft with ROPS Step 3, during the FMS preparation, the flight crew will see a _ROW/ROP >_ prompt at the bottom of the _PERF APPR_ page. This leads to the _RWY COND FOR ROW/ROP_ page (A320 family) where the flight crew can select the appropriate runway condition.

(table 1) ROPS actions during descent preparation

Regardless of the ROPS standard, during final approach, 

• If an amber message appears on the PFD, the flight crew must quickly analyze the situation: If IF WET : RUNWAY TOO SHORT appears (step2), they must perform a go-around if the runway is not dry or contaminated, and can continue the approach if the runway is dry. If RUNWAY TOO SHORT appears (Step2+ or Step 3), the flight crew should consider a go-around depending on the situation
• If a red RUNWAY TOO SHORT message appears, the flight crew must immediately perform a go-around.

(table2) ROPS actions during final approach

During the landing roll, there is no difference between the ROPS standards. The handling of alerts is identical.

(table 3) ROPS actions during landing roll

Level B (aided instruction) training is needed for the use of ROPS. Computer Based Training (CBT) is available, free of charge, and covers the following topics:

• ROW/ROP objectives
• Operating domain
• ROW/ROP function overview

⁽*⁾ hardware modification to add the ROW/ROP runway condition selector

(table 4) Simulator package for A320 family and A330 aircraft

The below table  provides the date of availability of each ROPS standard (table1). The year of application of the current default standard installed in the production line (linefit) for each aircraft type is highlighted in green.

Today, all newly delivered A320 family, A330, and A350 aircraft are equipped with a ROPS standard compliant with the ROAAS mandate.

The introduction of the ROAAS on A220 aircraft is expected in 2027. An exemption period of the ROAAS mandate is expected pending the availability of the function.

(table 5) Date of availability of each ROPS standard

Operators with A320 family or A330 aircraft that are not equipped with ROPS can retrofit one of the ROPS standards, provided that the necessary system prerequisites are installed.

In November 2025, the in-service fleet status concerning the ROPS function shows that 35.4 % of the A320 family in-service fleet is equipped with ROPS, representing 3 859 aircraft. It also highlights that 2 708 additional A320 family aircraft could easily activate ROPS since they have all the system hardware prerequisites already installed.

Similarly, 22.9 % of the A330 in-service aircraft fleet is equipped with ROPS and 308 A330 aircraft have all the hardware prerequisites to  activate ROPS. 

Operators wishing to retrofit ROPS on their aircraft can contact Navblue via https://www.navblue.aero/contact/.

(fig.14) ROPS in-service fleet status