Takeoff dispatch
Choose the aircraft configuration and the runway you are actually using, then let VPT work through the applicable limits.
Performance Calculation
Aircraft performance.
Aircraft performance.
Like real pilots.
Takeoff and landing performance built from detailed aircraft, airport, obstacle and weather data.
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Performance calculations run
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Aircraft variants modelled
EASA · FAA
Certification frameworks
16 airports included. No credit card required.
01 / Why performance matters
Every result has a limiting factor.
Aircraft are certified and operated within defined performance margins. Before takeoff and landing, operators use dedicated performance systems to determine whether the aircraft can safely and legally operate from the selected runway under the expected conditions.
The important point for VPT users is simple: runway length alone is not enough. Wind, temperature, slope, obstacles, aircraft configuration, engine-out climb capability, braking and operational restrictions can all change the result.
A performance calculation is not a single formula. It is a comparison of multiple limits — and the most restrictive one becomes the answer.
02 / The tool
The complexity is real.
The complexity is real.
Using it doesn't have to be.
VPT is designed to give beginners a clear result while still exposing the technical detail experienced pilots expect. Much of the input can be automated, while the calculation itself evaluates the full set of applicable performance limits behind the scenes.
Same workflow, every family
Field length, climb, obstacles, tyres and brakes are evaluated independently, whichever aircraft you fly.
Landing dispatch
Before departure, VPT returns the maximum allowable landing weight for the destination and alternate.
Landing enroute
Before arrival, the same model runs again against the latest conditions to return actual landing distance and braking options.
03 / Takeoff performance
Takeoff dispatch
VPT determines how much weight the aircraft can take off with, which speeds to use, and which configuration produces the appropriate result for the runway and conditions selected.
The final performance-limited takeoff weight is simply the lowest weight allowed by all applicable limits.
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performance calculations run through VPT to date
The most restrictive limit sets the final takeoff weight.
Use the margin
Full thrust isn't always necessary.
If the actual takeoff weight is below the performance-limited takeoff weight, the aircraft does not necessarily need full rated thrust.
That available performance margin can often be exchanged for reduced takeoff thrust, lowering engine temperature and reducing engine wear while still meeting the required takeoff margins. Reduced-thrust takeoffs are commonly achieved through a fixed derate, assumed temperature / FLEX, or a combination of both where supported.
Derate
A fixed derate selects a lower certified takeoff thrust rating. For that takeoff, the engine is treated as a lower-rated engine, reducing the available thrust limit.
Because the certified thrust rating itself is lower, minimum control speeds such as VMCG and VMCA may also be reduced.
Assumed temperature / FLEX
Assumed Temperature — called FLEX on Airbus — reduces commanded takeoff thrust by telling the performance system to calculate as though the outside temperature were higher than it actually is.
Unlike a fixed derate, the engine's certified rating has not changed. The minimum control speeds therefore remain based on the applicable full-rated configuration rather than receiving the same benefit as a derated rating.
Why the difference matters
When VMCG is the limiting factor, a fixed derate can sometimes improve the result in a way that assumed temperature alone cannot, because the lower certified thrust rating can also reduce the applicable minimum control-speed limitation.
Example — 737-700 BBJIts short fuselage gives the rudder a relatively shorter moment arm, while the CFM56-7B27-B3 engines provide very high thrust. At low weights, that combination makes VMCG the limiting factor rather than runway length or climb performance.
At full-rated thrust, an acceptable takeoff solution may therefore not exist.
Selecting a fixed derate lowers the applicable certified thrust rating and can reduce VMCG enough to bring the calculation back within the allowable speed range. Assumed temperature alone cannot provide the same benefit because it does not change the certified thrust rating used for the control-speed limitation.
VPT Optimum RatingVPT can handle this automatically. When using Optimum Rating, VPT evaluates the available thrust ratings and determines the performance-limited takeoff weight at the highest suitable rating that is not constrained by VMCG, avoiding the need to manually test each derate.
On supported aircraft, a derated thrust rating can also be combined with assumed temperature to further reduce thrust while remaining within the available performance margin.
Deeper performance detail
V1 isn't always one fixed number.
For a given takeoff, V1 can exist within an allowable range. Changing V1 changes the balance between the accelerate-stop distance required and the engine-out takeoff distance required.
VMCG ≤ V1 ≤ VR
Lower V1
Shorter accelerate-stop distance required. Longer engine-out takeoff distance required.
Optimum V1 — VPT
Balances the applicable go and stop requirements.
Higher V1
Longer accelerate-stop distance required. Shorter engine-out takeoff distance required.
VPT uses an optimum V1 strategy to balance the applicable takeoff-go and accelerate-stop requirements while considering factors such as runway, wind, slope and obstacle limitations.
Development note
VPT currently applies its own V1 optimization logic automatically. We are investigating an option that would allow users to select the V1 logic or strategy used for the calculation. This remains under evaluation, with no release timeframe announced.
Technical note
Why VPT may disagree with the CDU/MCDU
Your CDU/MCDU does not perform the complete runway-performance calculation. It may provide reference or default takeoff speeds, but it does not account for every optimization available to a dedicated performance tool, such as optimum V1, improved climb, runway slope or obstacle limitations.
Operator procedures and manufacturer documentation direct crews to use the result from the applicable performance system — such as OPT or FlySmart — when determining takeoff performance. A difference is therefore not necessarily an error; in many cases it is the expected result of a more complete calculation.
Improved climb
Excess runway can be exchanged for higher takeoff speeds, increasing engine-out climb capability and potentially improving the allowable takeoff weight.
Extended 2nd segment
Keeping takeoff configuration longer before accelerating can improve obstacle clearance when distant obstacles are limiting. VPT accounts for the applicable acceleration-height and engine-time constraints where supported.
Line-up correction
When runway entry geometry prevents the aircraft from starting exactly at the threshold, the usable takeoff distance may need to be reduced. VPT applies the appropriate alignment correction where required.
04 / Engine-out performance
Engine Failure Procedures
When terrain or obstacles make a straight-ahead engine-out departure unsuitable, the takeoff calculation may depend on an Engine Failure Procedure (EFP) tailored to that runway and airport.
VPT uses the applicable engine-out path to evaluate obstacle clearance instead of assuming the aircraft simply continues along the runway heading.
From published text to performance process
An Engine Failure Procedure is not just a text instruction for the pilot. The published text is the operational translation of a much deeper performance process. For each applicable aircraft and runway, the EFP defines the cone in which terrain and published obstacles must be gathered and analysed.
VPT uses that cone to:
- build the obstacle-analysis cone
- analyse terrain and published obstacles inside it
- identify the obstacles that can affect takeoff performance
- store those relevant obstacles for use in the takeoff calculation
The EFP defines the cone in which terrain and obstacles are gathered and evaluated for the takeoff calculation.
Aircraft-specific analysis
The limiting obstacles are then evaluated whenever the corresponding takeoff performance calculation is performed. This analysis is aircraft-specific: the engine-out path and the resulting obstacle set may depend on the runway, the procedure, and the applicable aircraft type / variant performance characteristics.
Why it matters
The engine-out flight path used after takeoff can materially change the obstacle-limited takeoff weight.
Why custom EFPs are not supported
VPT cannot accept arbitrary user-created Engine Failure Procedures because a valid procedure requires more than a text description or a set of waypoints. The corresponding obstacle-analysis geometry and obstacle dataset must also be generated and validated for the relevant runway and aircraft before the procedure can be used reliably in performance calculations.
Explore how VPT builds airport and obstacle data
Contamination can behave in unexpected ways.
Runway condition is more than simply dry or wet. Depending on the aircraft, manufacturer performance data may include conditions such as Dry, Wet, Slippery Wet, Good, Good-to-Medium, Medium, compacted snow, standing water, slush, dry snow and wet snow, together with applicable contaminant depths.
VPT uses the runway conditions and contaminants supported by the manufacturer performance data available for each aircraft type, rather than applying one generic penalty to every degraded runway.
A shallow layer of contamination may primarily reduce braking effectiveness. As loose contamination becomes deeper, however, it can also create additional displacement, impingement and rolling resistance during the takeoff roll.
Because these effects interact differently depending on contaminant type and depth, a deeper contaminant is not always associated with a lower performance-limited takeoff weight than a shallower one.
VPT models the applicable manufacturer data rather than assuming that every increase in contamination produces the same type of performance penalty.
Did you know?
Assumed Temperature / FLEX is not permitted for every contaminated-runway condition.
On some slippery or contaminated surfaces, aircraft procedures prohibit assumed-temperature reduced thrust even though a fixed derate may still be permitted. The exact restriction depends on the aircraft and its approved performance data.
VPT applies the corresponding aircraft-specific limitation automatically, preventing an assumed-temperature / FLEX solution where the applicable performance data does not permit it.
05 / Landing performance
One landing calculation.
One landing calculation.
Two different moments in the
flight.
Landing performance answers two different questions depending on when the calculation is performed.
Before departure
Landing Dispatch
Can the aircraft be dispatched to the destination and alternate at the expected landing weight and forecast conditions?
Key output
Maximum allowable landing weight
VPT determines the most restrictive applicable landing weight from:
- Field length
- Landing climb
- Approach climb
- Tyre speed
- Brake energy
- Missed-approach climb gradient
- Maximum structural landing weight
- Most favourable runway limitation, where applicable
Maximum landing weight is computed both as a normal landing weight and a with-ice landing weight where applicable.
Before arrival
Landing Enroute
Using the latest aircraft and runway conditions, VPT determines the actual landing-distance information and braking options needed for the arrival.
Key output
Actual landing distance & braking
Includes:
- Factored and unfactored landing distances
- Autobrake settings
- Runway exits
- Brake cooling schedule, where supported
- Expected brake temperature, where supported
- Applicable non-normal penalties
Landing Enroute builds on the same underlying landing-performance model as Dispatch, but uses the latest conditions and provides operational landing-distance information.
Deeper landing detail
MACG
Some procedures require a higher-than-standard missed-approach gradient because of terrain or obstacles.
Quick turnaround
Where supported, VPT calculates the maximum landing weight compatible with the required turnaround constraint.
Autoland increment
Where required, VPT applies the manufacturer's additional autoland landing-distance increment automatically.
Brake cooling
Where supported, VPT provides expected ground / air cooling information after landing.
Runway exits
Landing distance can be compared with available exits for a more realistic braking strategy.
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runway exits in the database
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non-standard missed-approach climb gradients implemented
06 / Automatic inputs
Weather in.
Weather in.
Calculation ready.
VPT can retrieve and decode METAR, TAF and VATSIM/IVAO ATIS data, then use METAR2VPT to populate much of the performance calculation automatically — including wind, runway condition, anti-ice requirements and other relevant inputs.
As pilot in command, you remain responsible for reviewing the imported conditions before calculating. Significant conditions such as gusts, precipitation, low visibility or convective weather are highlighted for review.
Real-world D-ATIS
Planned for a future update.
07 / Advanced operations
When the operation becomes less routine.
VPT extends beyond the standard case, accounting for changing airport conditions and aircraft-specific operational penalties where supported.
Live Airport Updates
Performance-relevant airport changes can be incorporated into the calculation as they occur. At airports covered by Active Monitoring, the Provider's performance officers review operational changes, while Automated Runway Monitoring detects runway closures across the full database.
Explore airport monitoringNNC
Where aircraft data supports it, applicable Non-Normal Checklist penalties can be applied directly to the landing calculation.
Check aircraft availabilityMEL / CDL
Where supported, dispatch performance can account for applicable MEL/CDL penalties directly in the calculation.
Check aircraft availabilityAircraft-specific availability NNC and MEL/CDL coverage varies by aircraft variant and available performance data. See the Fleet page for current support.
Performance, made accessible
Professional-level performance.
Professional-level performance.
A few clicks away.
Behind every result sits aircraft data, airport data, weather, operational configuration and a chain of performance limits. VPT brings that complexity together so you can focus on the flight — while still seeing what drives the numbers.
Virtual Performance Tool is intended exclusively for flight simulation and training purposes and is not approved for real-world flight operations.