Cost Index
COST INDEX
1️⃣ What is the Cost Index?
2️⃣ Which Cost Index should be used in simulation?
3️⃣ List of Cost Index values used by various airlines
4️⃣ Glossary
1️⃣ What is the Cost Index?
The Cost Index, or CI, is used to minimize the overall cost of a typical mission. This cost mainly comes from two sources: hourly operating costs (crew, maintenance) and fuel cost. The Cost Index synthesizes these aspects by calculating the ratio between these two cost sources.
The Cost Index therefore allows airlines to prioritize either flight time or fuel savings, depending on the operational conditions they wish to use.
Based on the Cost Index, the FMS optimization model can compute the optimal flight speeds and altitudes. These speeds and altitudes are pre-calculated on the ground and stored as performance models. They depend on current flight parameters—especially weight—and correspond to a nominal aircraft.
Using this data, the FMS builds the vertical profile of the trajectory using a straightforward construction method.
It should be noted that Cost Index values used by airlines are not fixed; they are often adjusted depending on fuel prices and other economic factors.
In practice, it is very common for pilots to adapt the Cost Index according to the needs of the day or the specific flight (or even their preferences), and to enter a CI different from the one planned in the flight release.
The Cost Index can be defined using a mathematical formula, but units vary depending on the manufacturer, which makes direct comparison impossible.
The formula is: CI = (Ctime) / (Cfuel)
Below are the formulas for Airbus and Boeing:
Airbus : CI = ($/minute of flight) / ($/kg of fuel)
Boeing : CI = ($/hour of flight) / ($/100 lbs of fuel)
You will find two documents HERE and HERE regarding the Cost Index for Boeing.
You will find a document HERE regarding the Cost Index for Airbus.
Summary table of typical Boeing Cost Index values
| Aircraft | MRC | Typical CI | LRC |
| 717-200 | 0 | 5 to 25 | 25 |
| 737-300/400/500 | 0 | 10to 30 | 30 |
| 737-600/700/800 | 0 | 10 to 30 | 35 |
| 757-200/300 | 0 | 15 to 50 | 85 |
| 767-300/300ER | 0 | 15 to 50 | 70 |
| 777-200/300 | 0 | 90 to 150 | 180 |
| MD-11 | 0 | 80 to 120 | 200 |
| 747-400 | 0 | 25 to 80 | 230 |
Summary table ECON cruise for Boeing aircraft
| CI | 100kt vent arrière | Sans vent | 100kt vent de face |
| 0 | 0.773 | 0.773 | 0.785 |
| 80 | 0.787 | 0.796 | 0.803 |
| Max | 0.811 | 0.811 | 0.811 |
2️⃣ Which Cost Index should be used in simulation?
A typical CI value ranges from 0 to 200, but it can be higher (up to 9999 on Boeing aircraft).
- A319/320/321 – Medium-haul: CI 50
- A319/320/321 – Short-haul: CI 80
- A319/320/321 – Shuttle operations: CI 150
- A330 – Medium-haul: CI 60
- A330 – Long-haul: CI 30
- Fokker 100 – TAY650 engines: CI 40
- Fokker 100 – TAY620 engines: CI 24 until cruise, then CI 40 during cruise
In case of a delay in the schedule, a CI of 200 may be used.
If in doubt, or if the aircraft is not listed, CI 80 is a good average value to use in flight simulation.
3️⃣ List of Cost Index values used by various airlines:
Aegean Airlines
Airbus A320
Cost Index : 20
Airbus A321
Cost Index : 25
Air Berlin
Airbus A319
Cost Index : 6
Airbus A320/A321
Cost Index : 8
Airbus A330-200
Cost Index : 80
Boeing 737-700/800
Cost Index : 8
Air France
Airbus A319/320/321 Medium haul
Cost Index : 50
Airbus A319/320/321 Short haul
Cost Index : 80
Airbus A319/320/321 Shuttle
Cost Index : 150 (250 if late)
Airbus A330-200 Medium haul
Cost Index : 60
Airbus A330-200 Long haul
Cost Index : 30
Britair
Fokker 100 - TAY650 engines
Cost Index : 40
Fokker 100 - TAY620 engines
Cost Index : climb at 24 then cruise at 40
British Airways
Airbus A318
Cost Index : 30
Airbus A319/A320/A321
Cost Index : Under FL100 CI 0 - Above FL100 CI 15
Boeing 737-300/400/500
Cost Index : 28
Boeing 747-400
Cost Index : 50
Boeing 757-200
Cost Index : 40
Boeing 767-300
Cost Index : 40
Boeing 777-200/300
Cost Index : 100
Boeing 787
Cost Index : 25
Airbus A380
Cost Index : 120
Condor
Airbus A320
Cost Index : 26
Airbus A321
Cost Index : 33
Boeing 757-300
Cost Index : 30
Boeing 767-300ER
Cost Index : 30
Delta Airline
Boeing 767-300ER
ECON - Cost Index: 113
Tail wind or early - Cost Index : 75
Headwind or late - Cost Index : 377
Boeing 747-400
Cost Index : 100
EasyJet
Airbus A319
Cost Index : 12
Airbus A320/A320SL
Cost Index : 12
Airbus A321
Cost Index : 23
Egyptair
Boeing 737-500
Cost Index : 18
Boeing 737-800
Cost Index : 22
Airbus A320
Cost Index : 23
Airbus A321
Cost Index : 25
Airbus A330-200/300
Cost Index : 35
Boeing 777-200
Cost Index : 37
Boeing 777-300ER
Cost Index : 44
Emirates
Airbus A330-200
Cost Index : 25
Airbus A340-300
Cost Index : 24
Airbus A340-500
Cost Index : 28
Airbus A380-800
Cost Index : 50
Boeing 777-200LR/200LRF
Cost Index : 35
Boeing 777-200ER
Cost Index : 36
Boeing 777-300ER
Cost Index : 36
Etihad
Airbus A319
Cost Index : 18
Airbus A320
Cost Index : 16
Airbus A320SL
Cost Index : 18
Airbus A321SL
Cost Index : 15
Airbus A330-200
Cost Index : 23
Airbus A330-200F
Cost Index : 25
Airbus A330-300
Cost Index : 26
Airbus A340-500
Cost Index : 32
Airbus A340-600
Cost Index : 32
Boeing 777-200LR
Cost Index : 41
Boeing 777-200LRF
Cost Index : 44
Boeing 777-300ER
Cost Index : 44
Fly Dubaï
Boeing 737-800 : 15
FlyGlobespan
Boeing 737-700
Cost Index : 14
Boeing 737-800
Cost Index : 13
Hamburg international
Airbus A319
Cost Index : 40
Boeing 737-700
Cost Index : 30
Icelandair
Boeing 757-200
Cost Index : 16
Boeing 757-300
Cost Index : 18
Jet2
Boeing 737-300
Cost Index : 0
KLM
Airbus A330
Cost Index : Climb at 60, cruise at 150 (300 if late) and descent at 30
Fokker 100 - TAY620 engines
Cost Index : Climb at 24 then cruise at 40
Fokker 100 - TAY650 engines
Cost Index : 40
Fokker 70
Cost Index : 40
McDonnell-Douglas MD-11
Cost Index : Climb at 50, cruise at 100 and descent at 20
Nordavia
Boeing 737-500
Cost Index : 27
Norwegian
Boeing 737-800
Cost Index : 15
Nouvelair
Airbus A320
Cost Index : 38
PIA
Boeing 777-200ER/200LR
Cost Index : 180
Boeing 777-300ER
Cost Index : 180
Qatar Airways
Airbus A319CJ
From Doha - Cost Index 9
To Doha - Cost Index 8
Airbus A320
Cost Index : 10
Airbus A321
Cost Index : 11
Airbus A330-200/200F
Cost Index : 15
Airbus A330-300
Cost Index : 15
Airbus A 340-600
Cost Index : 21
Airbus A350-900
Cost Index : 30
Airbus A380-800
Cost Index : 160
Boeing 777-200LR/200LRF
From Doha - Cost Index 120
To Doha - Cost Index 110
Boeing 777-300ER
Cost Index : 120
Boeing 787-800
From Doha - Cost Index 110
To Doha - Cost Index 25
Ryanair
Boeing 737-800
Cost Index : 30
Royal Air Maroc
Boeing 737-700
Cost Index : 34
Boeing 737-800
Cost Index : 24 (50 when departing LHR, ORY et AMS)
Boeing 767-300
Cost Index : 39
Boeing 787-800
Cost Index : 42
Southwest Airlines
Boeing 737-300/500
Cost Index : 28
Boeing 737-700
Cost Index : 36
Thomas Cook UK
Airbus A321
Cost Index : 13
Airbus A330-200
Cost Index : 27
Boeing 757-200
Cost Index : 28
Boeing 757-300
Cost Index : 29
Boeing 767-300
Cost Index : 27
Thomson Airways
Airbus A320
Cost Index : 13
Airbus A321
Cost Index : 17
Boeing 737-300
Cost Index : 10
Boeing 737-800
Cost Index : 13
Boeing 757-200
Cos Index : 23
Boeing 767-300
Cost Index : 25
Boeing 787
Cost Index : 21
Transavia
Boeing 737-800 (CFM56-7B26-26k)
Cost Index : 36
Turkish Airlines
Boeing 777-300ER
Cost Index : 26
Tunisair
Airbus A320
Cost Index : 17
Boeing 737-600
Cost Index : 13
United Airlines
Flight duration under 4h :
Airbus A319/320
Cost Index : 27
Boeing 737-300/500
Cost Index : 35
Boeing 747-400
Cost Index : 90
Boeing 757-200
Cost Index : 80
Boeing 767-300
Cost Index : 65
Boeing 777-200
Cost Index : 85
Flight duration over 4h :
Airbus A319/320
Cost Index : 22
Boeing 737-300/500
Cost Index : 30
Boeing 747-400
Cost Index : 85
Boeing 757-200
Cost Index: 75
Boeing 767-300
Cost Index : 60
Boeing 777-200
Cost Index : 80
Virgin Atlantic
Airbus A330-300
Cost Index : 32
Airbus A340-300
Cost Index : 30
Airbus A340-600
Cost Index : 40
Boeing 747-400
Cost Index : de 73 à 93 - In general CI:75 Eastbound and CI:90 Westbound
Wizzair
Airbus A320/A320SL
Cost Index : 15
4️⃣ Glossary
- CI = Cost Index
- FMS = Flight Management System
- MRC = Maximum Range Cruise
- LRC = Long Range Cruise
- ECON = Economy
- MACH = The aircraft’s speed relative to the speed of sound, expressed as a percentage.
- Example: M.82 or M0.82 = 82% of the speed of sound.
- Since the speed of sound depends only on temperature, it is impossible to give an exact speed for a given Mach number without knowing the precise ambient temperature at that moment.