What is S/C on Airbus A320? (Step Climb)

Step Climb, abbreviated as S/C, is a climb procedure used by Airbus A320 aircraft to optimize fuel efficiency during long-haul flights. It involves executing a series of incremental altitude increases at predetermined waypoints along the flight path. Step climbing allows the aircraft to operate at higher, more fuel-efficient altitudes as the aircraft’s weight decreases throughout the flight. This technique helps to reduce fuel consumption, lower operating costs, and minimize the environmental impact of the aircraft.

In this article, we will explore the concept of Step Climb in more detail, understanding its purpose, benefits, and considerations for implementing this procedure on the Airbus A320.

The Importance of Step Climb

Step climbing plays a crucial role in optimizing the performance and efficiency of the Airbus A320 during long-haul flights. As an aircraft burns fuel during flight, its weight gradually decreases. By increasing the altitude incrementally, the aircraft can take advantage of the thinner air at higher altitudes, which reduces drag and improves engine efficiency.

Step climbing provides several benefits for both airlines and the environment. Let’s take a look at some of the key advantages:

1. Fuel Efficiency

Step climbing allows the aircraft to operate at more fuel-efficient altitudes as it progresses through the flight. As the aircraft’s weight reduces, the engines require less power to maintain the desired speed. By climbing to higher altitudes, the aircraft experiences reduced drag and can operate at a more optimal thrust setting, resulting in lower fuel consumption.

According to Airbus, implementing step climb procedures on the A320 aircraft can lead to fuel savings of up to 2-3% on long-haul flights. For airlines operating multiple A320s on a daily basis, this translates to significant cost savings and a reduced environmental impact.

2. Increased Range

By utilizing step climbing, the Airbus A320 can extend its effective range without the need for additional fuel. As the aircraft climbs to higher altitudes, it benefits from the increased lift provided by thinner air. This allows the aircraft to fly more efficiently, cover greater distances, and potentially reach destinations that would be challenging without step climbing.

For airlines, this expanded range opens up new route possibilities, improving their operational flexibility and enabling them to serve a wider range of destinations.

3. Environmental Impact

Step climbing also contributes to reducing the environmental impact of air travel. By optimizing the aircraft’s altitude according to its decreasing weight, step climbing minimizes fuel burn and, consequently, reduces greenhouse gas emissions.

A study conducted by Eurocontrol, the European Organization for the Safety of Air Navigation, demonstrated that implementing step climb procedures can lead to an overall reduction in CO2 emissions. The study estimated that step climbing can reduce emissions by up to 8% on long-haul flights, contributing to the industry’s sustainability goals.

Implementing Step Climb on the Airbus A320

While step climbing offers significant benefits, its implementation on the Airbus A320 requires careful planning and coordination between the flight crew, air traffic control, and airline operations. Here are some considerations for implementing step climb:

1. Weight and Balance

As the aircraft burns fuel and passengers consume onboard supplies, the weight gradually decreases. To optimize step climb, airlines should ensure an accurate estimate of the fuel burn and passenger consumption to plan the timing and altitude increments of each step. Incorrect weight predictions could result in premature or delayed step climb, impacting the fuel efficiency of the flight.

Proper weight and balance calculations are essential for achieving the desired fuel savings and maintaining the aircraft’s performance within safe limits.

2. ATC Clearance

Prior to initiating a step climb, the flight crew must obtain the necessary clearance from air traffic control (ATC). Clearances for step climbs are typically granted based on factors such as airspace congestion, traffic separation requirements, and aircraft performance capabilities.

Effective communication with ATC ensures a smooth and safe transition between altitudes, minimizing disruption to other aircraft operating in the surrounding airspace.

3. Optimal Cruise Altitude

The selection of the optimal cruise altitude is crucial for maximizing the benefits of step climbing. A careful evaluation of factors such as wind patterns, temperature variations, and airspace restrictions helps determine the most fuel-efficient altitudes at different stages of the flight.

Flight planning tools and performance calculations assist the flight crew in identifying the optimal cruise altitude for each segment of the flight, allowing for efficient step climbing.

While step climbing offers significant advantages, it is important to analyze each flight’s specific conditions and consult with company procedures to ensure the appropriate application of this technique.


Step Climb, or S/C, is an essential procedure for optimizing fuel efficiency and performance during long-haul flights on the Airbus A320 aircraft. By incrementally climbing to higher altitudes as the aircraft’s weight decreases, step climbing allows for reduced fuel consumption, increased range, and a minimized environmental impact.

Airlines that adopt step climb procedures on the A320 can benefit from significant fuel savings, extended range capabilities, and contribute to the industry’s sustainability goals. However, it is essential to consider factors such as weight and balance calculations, ATC clearances, and the selection of optimal cruise altitudes to ensure the successful implementation of step climbing.

With proper planning and coordination, step climb serves as an effective tool for enhancing operational efficiency, reducing costs, and promoting a more sustainable future for air travel.

For More: What is ASI on Airbus A320? (Air Speed Indicator)