Short Haul – The Methodology Calculations for Fuel Cost Saving

The methodology used to estimate the annual fuel cost savings from reducing a typical short-haul aircraft weight by 1 kg.

Establishing the Assumptions

Before diving into the math, we start by laying out all the assumptions:

  • Flight Distance for a Typical Short-Haul Aircraft: 1,140 km per flight.
  • Fuel Savings Factor: It is assumed that reducing the weight by 1 kg saves about 3 grams (0.003 kg) of fuel per kilometre flown. This rule-of-thumb is based on typical performance data and aerodynamic considerations.
  • Flight Frequency: 4-6 flights per day (average 5 flights per day).
  • Annual Flight Distance: 1.8 million km per year.
  • Fuel Cost: $0.675 per kg of fuel.
  • Weight Reduction: 1 kg.

These assumptions simplify the real-world complexities of aircraft operations but provide a good baseline for estimation.

Calculating Fuel Savings per Flight

The first step is to determine how much fuel is saved on a single flight when the aircraft’s weight is reduced by 1 kg.

Step 2.1: Apply the Fuel Savings Factor

For every kilometre flown, a 1 kg weight reduction saves 0.003 kg of fuel. Therefore, for a flight covering 1,140 km:

  • Fuel saved per flight: 1,140 km × 0.003 kg/km = 3.42 kg.

Thus, each flight saves approximately 3.42 kg of fuel.

Estimating Annual Fuel Savings

Next, we extend the per-flight savings to an annual figure by incorporating the number of flights the aircraft makes in a year.

Step 3.1: Multiply by Annual Flight Frequency

  • Annual flights: 5 flights/day × 365 days/year = 1,825 flights/year.
  • Annual fuel savings: 3.42 kg/flight × 1,825 flights = 6,241.5 kg.

So, over the course of one year, a 1 kg weight reduction would save approximately 6,241.5 kg of fuel.

Converting Fuel Savings into Cost Savings

Finally, we translate the fuel savings into a monetary value using the given fuel cost.

Step 4.1: Multiply by Fuel Cost per Kilogram

  • Annual cost savings: 6,241.5 kg × $0.675 per kg ≈ $4,210.

Rounded off, the annual savings are roughly $4,210.

Integrating Findings from the First Methodology

Based on the first methodology, we know that a 1 kg weight reduction yields significant financial savings and emissions impact:

  • Financial Savings: $20,000 for 1 kg weight reduction.
  • Emissions Impact: 0.0945 kg of CO2 per 1,000 km for 1 kg weight reduction.

Updated Calculations for 1 kg Weight Reduction

  1. Annual Fuel Savings:
    • Fuel saved per flight: 3.42 kg.
    • Annual fuel savings: 3.42 kg/flight × 1,825 flights = 6,241.5 kg.
  1. Annual Cost Savings:
    • Annual cost savings: 6,241.5 kg × $0.675 per kg ≈ $4,210.
  1. Emissions Savings:
    • CO2 savings: 0.0945 kg of CO2 per 1,000 km for 1 kg weight reduction.

Considerations and Caveats

  • Rule-of-Thumb Estimate: The factor of 0.003 kg fuel saved per km per 1 kg weight reduction is a simplified estimate. Actual savings can vary based on flight conditions, aircraft configuration, and operational procedures.
  • Flight Profile Variability: Different flight distances, altitudes, or weather conditions could alter the fuel burn rate.
  • Operational Factors: The frequency of flights, actual route distances, and variations in fuel prices can all impact the final cost savings.
  • Aerodynamic and Engine Efficiency: The effect of weight reduction is non-linear in practice; changes in drag and engine performance might slightly alter the savings compared to this simple calculation.

 

 

Conclusion

In summary, under the assumed conditions—a 1,140 km short-haul flight on a typical short-haul aircraft, 1,825 flights per year, a fuel savings factor of 0.003 kg/km per 1 kg weight reduction, and a fuel cost of $0.675 per kg—a 1 kg weight reduction would save:

  • 3.42 kg of fuel per flight.
  • 6,241.5 kg of fuel per year.
  • Approximately $4,210 in fuel cost annually.
  • 0.0945 kg of CO2 per 1,000 km.

This expanded methodology shows how to combine operational assumptions, per-flight fuel savings, and annual flight frequency to arrive at an estimated annual cost savings and emissions impact from a small weight reduction.

References:

  • Eurocontrol Data Snapshots and aviation overview reports for traffic statistics and utilization trends​
  • Airbus and industry publications for aircraft utilization (flight hours and cycles) of A320-family short-haul jets​
  • IATA and ch-aviation data on European fleet sizes and airline counts
  • Airline annual reports (e.g. easyJet, Ryanair) for utilization metrics corroborating these averages​

Each source provides context for the typical operational tempo of short-haul aircraft in Europe.

 

Below is a list of sources and references that underpin the methodology and rule‐of‐thumb used in our fuel cost savings calculation. Note that the 3 g/km per kg reduction is a widely cited industry estimate that draws from multiple technical documents, industry reports, and academic studies. While not all sources state the figure explicitly, they provide the context for its use:

Ready to start a conversation?

Bournemouth Office:
Building 307,
Aviation Park West,
Bournemouth Airport,
Dorset,
BH23 6NW
France Office:
ATL Europe,
3 rue Franche Comté,
Pépinière d’Entreprises BP311,
50103 Cherbourg en Cotentin,
France