1. TAKEOFF PERFORMANCE
The performance data for takeoff and landing an aircraft can be obtained from the aircraft's flight manual or pilot's operating handbook. The actual performance of an aircraft is affected by many variables which must be taken into account.

2. TAKEOFF CONSIDERATIONS
Factors to Consider:
Aircraft Gross Weight
Available Engine Thrust
Field Elevation
Pressure Altitude
Temperature
Winds
Runway Length
Runway Slope
Runway Condition
Terrain & Obstacles
MEL/CDLs
Icing
Improving Performance:
Engine Bleeds Closed.
Static vs. Flex Takeoff.
Flap Configuration (Less flaps = longer takeoff roll but better climb performance).
The weight of an aircraft is one of the basic factors that determines the length of the landing roll of an aircraft. An increase in weight increases the stall speed of an aircraft. Stall is a reduction in the lift coefficient generated by a wing as angle of attack increases. Therefore, the minimum approach speed is much higher in case of heavier aircraft's. The kinetic energy  that has to be overcome to stop an airplane, is a function of the mass of the airplane and the square of the speed at touchdown. The kinetic energy in case of heavier aircraft's is higher and the brakes have to absorb this greater energy, increasing the landing run of an aircraft.
A decrease in density of air results in decrease in both aircraft and Engine performance. High elevation airports are characterized by low pressure and high ambient temperatures. The  TAS will be higher than the Indicated airspeed indicated by the Airspeed indicator to the pilot in air of low density. This increase in TAS leads to greater touchdown speed hence increases the landing roll. More energy has to be absorbed by the brakes thus demanding the need of a longer runway. An increased density altitude means a longer landing distance.
The headwind reduces the landing distance for an aircraft. Landing into a headwind reduces the GS for the same TAS. This is beneficial to both, the pilots as well as the Air traffic controllers (ATC). An aircraft landing into a headwind will require lesser runway and will be able to vacate the runway sooner. If the headwind decreases near the ground, there's a decrease in the performance of the aircraft and it will tend to sink and possibly under shoot the aiming point. Tailwind increases the Ground Speed of an aircraft for the same TAS and thus a longer runway distance will be required for an aircraft to land. Landing in a tailwind situation could lead to a stall because of the tendency of the pilot to reduce the airspeed while landing. Also, there's a chance of over shooting the runway and colliding with objects or terrain.

3. TAKEOFF SPEEDS V1 (Takeoff Decision Speed)
V1 is selected so that if an engine failure is recognized:
1) at or above this speed, the takeoff may be continued with one engine inoperative, or
2) at or prior to this speed a stop may be initiated and completed within the runway remaining.
The stopping distance is based on retarding the thrust levers to idle, maximum braking on a dry runway, and full spoiler extension.
The effect of reverse thrust is not included in the computation.
Jeppesen computes V1 for its customers based on the worst performing jet aircraft is use – the B with the smaller engines. They guarantee that if your pilots reject at or after V1, that they will clear all obstacles on departure as their aircraft will out perform a B

4. TAKEOFF SPEEDS VR (Rotation Speed)
The speed at which the pilot begins to rotate the aircraft to the takeoff attitude. The rate of rotation may vary but rotation at the optimum rate will result in a minimum liftoff speed (Vlof).
This optimum rotation rate will result in attaining V2 speed at 35 feet at the end of the runway with one engine inoperative, or attaining the V2 speed at 35 feet over the runway with 15% of the runway remaining from that point with all engines operating.
Keep in mind that the main gear are still on the runway at this point.
This is where the nose wheel comes off the runway.

5. TAKEOFF SPEEDS VLOF (Lift-off Speed)
The speed at which the aircraft first becomes airborne.
* Takeoff speeds vary with aircraft weight, aircraft configuration (flaps, bleeds, anti-ice, anti-skid, etc.), and runway conditions (contamination).
This speed is not computed by dispatchers or pilots. This is when the main gear leaves the runway surface.

6. TAKEOFF SPEEDS V2 (Takeoff Safety Speed)
The greater of a speed at 35 feet above the takeoff runway or a speed at least 20% above the stall speed, with the aircraft in the takeoff configuration.
The correct V2 is a result of proper rotation and liftoff procedures and allows the aircraft to maintain a specified gradient in the climb.
This is essentially the best one-engine operative angle of climb speed for the aircraft and should be held until clearing obstacles after takeoff, or until at least 400 feet above the ground also known as “first segment climb”.
V2 is the speed based on the lower of two weights, the runway limit weight and the climb limit weight which guarantees obstacle clearance if an engine is lost at or after V1.
Upon achieving V2 speed, the crew can retract the first notch of flaps, retract the gear, and now bank the aircraft up to 15 degrees in a turn, if necessary.

7. TAKEOFF SPEEDS Vmc (Minimum Control Speed)
Minimum control speed with the critical engine inop.
Vmcg (Minimum Control Speed/Ground)
Minimum speed at which directional control can be maintained on the ground using only control surfaces after an outboard engine fails during takeoff.
Vmca (Minimum Control Speed/Air)
Minimum speed at which straight flight can be maintained with zero yaw and no more than 5 degree bank towards the operative engine after an outboard engine fails and takeoff power on the operative engine(s).
V2 is the speed based on the lower of two weights, the runway limit weight and the climb limit weight which guarantees obstacle clearance if an engine is lost at or after V1.
Upon achieving V2 speed, the crew can retract the first notch of flaps, retract the gear, and now bank the aircraft up to 15 degrees in a turn, if necessary.

8. CLEARWAY & STOPWAY
Clearway refers to specific conditions existing in conjunction with a particular runway that may be used by the operator to improve the performance margin of the aircraft through extension of the runway length requirement when operationally advantageous.
A Clearway is defined as an area beyond the runway, not less than 500 feet wide, centrally located about the extended centerline of the runway, above which no obstacles protrude.
A Stopway is an area beyond the takeoff runway able to support the aircraft during an aborted takeoff, without causing structural damage to the aircraft. Cannot be used in takeoff computations.
These definitions may be asked of the student on the FAA computer exam.

9. DECLARED RUNWAY DISTANCES
TORA Takeoff Run Available (Takeoff Ground Run Available)
TODA Takeoff Distance Available (TORA + Clearway)
ASDA Accelerate-Stop Distance Available (TORA + Stopway)
LDA Landing Distance Available
These distances are the basis for runway performance calculations and do no necessarily correspond to the lengths depicted on the Jeppesen charts.
Nice to know but not on the FAA computer knowledge exam or asked on the FAA practical exam.

10. TAKEOFF
The regulations require specific operational limitations for operations on or near the runway environment and during initial climb away from the terminal environment.
Weight planning and establishing weight limitations for the aircraft allows the airline to ensure the aircraft meet these requirements depending on ambient conditions.
Separate weight limitations are created for the Runway (the Runway Limit Weight) for operations up to 35 feet above the surface, and for the Climb (the Climb Limit Weight), which covers initial climb from 35 feet to 1500 feet.
This data is created through testing during aircraft certification and is further refined by engineers (Jeppesen, Aerodata, etc.) and published in the “Runway Analysis.”
There are 4 segments of the climb terminating at 15,00 ft AGL as defined by the manufacturers.
More on this shortly.

11. MGTOW
The Maximum Gross Takeoff Weight is computed by finding the most restrictive (lowest weight) of the following:
1. Takeoff Runway Limit Weight (Performance)
2. Takeoff Climb Limit Weight (Performance)
3. Structural Takeoff Limit Weight (Structural)
The Takeoff Climb Limit Weight is also known at the WAT limit.
W – Weight
A – After
T- Takeoff, or
Weight, altitude, temperature.

12. TAKEOFF RUNWAY LIMIT WEIGHT
The minimum takeoff length required varies with gross weight, temperature, altitude, wind, runway gradient, & clutter.
The Takeoff Runway Limit Weight ensures, that based on ambient conditions, we will have enough runway available to comply with all the following distance requirements: Accelerate-Stop Distance Takeoff with an Engine Failure Distance All-Engine Take-Off Distance
Dispatchers & crews will make sure the airplane is within weight limitations that ensure there is enough runway to either reject the takeoff and stop, or climb to a prescribed altitude above the runway with one or all engines operating (35 feet).
The idea is to make money which means carry as much payload as possible.
If the weights are restricted with the first calculation, try a chart with a different flap setting for takeoff.
The crews can ask for a different runway, preferably with a headwind component, which will give them better performance.
Turning the PACKs (Pressurization and Air Conditioning Kits) Off will allow a higher payload because the PACKs use bleed air from the engines, and now they will have more power in an OFF condition.
Lots of variables allows the dispatcher and pilots to manipulate the numbers for best payload.
Supplemental (charter) flights will often depart at night when the ambient temperature is cooler, allowing for a higher payload.

13. TAKEOFF RUNWAY LIMIT WEIGHT
Accelerate-Stop Distance
The distance required to accelerate to the decision speed (V1) with all engines operating normally, experience the loss of an engine at V1, retard the thrust lever(s) on the operating engine(s), and bring the airplane to a full stop.
Only spoilers and anti-skid brakes are used for stopping. Reverse thrust is not utilized in demonstrating this distance.
A stopway can be calculated as part of this distance, but not all airlines do this.
Stopway 13

14. TAKEOFF RUNWAY LIMIT WEIGHT
Takeoff Distance With an Engine Failure
Distance required to accelerate to V1 with all engines operating normally, experience the loss of an engine, continue to accelerate on the remaining engine(s) to Vr at which time rotation is commenced so as to reach a height of 35 feet above the runway surface at V2.
The clearway distance can be used in this computation.
Sometimes referred to as the Accelerate-Go Distance. 14

15. TAKEOFF RUNWAY LIMIT WEIGHT
All Engine Takeoff Field Length
Demonstrated distance from brake release to a point where a 35 feet height above the surface is reached with all engines operating normally plus 15% of the runway distance.
Essentially 115% of our distance to reach 35 feet on all engines operating must still put us over the runway surface.
A clearway can be used in distance calculation. 15

16. TAKEOFF RUNWAY LIMIT WEIGHT
Balanced Field Length
The runway length (or runway length plus clearway) where, for the takeoff weight, the engine-out accelerate-go distance equals the accelerate-stop distance.
The stopway is not used in computing a balanced field.
When the runway length is balanced, this often results in the shortest runway distance required and the highest allowable takeoff weights.
Takeoff speeds are usually calculated in such a way to create a balanced field length. 16

17. AIRPORT/RUNWAY ANALYSIS
Takeoff
Data ensures compliance with basic takeoff limiting conditions - Field Length, Minimum Climb Gradient, Obstacle Clearance, Tire Speed, and Brake Energy.
Jeppesen combines required runway performance and obstacle clearance into the published runway limit weight.
The published runway limit weight assures required performance and obstacle clearance up to 1500’ AGL or until all obstacles are cleared up to 30 NM from the departure airport.
The published Climb Limit Weight does not guarantee obstacle clearance - just a positive single-engine rate of climb at the temperature and pressure altitude on the chart to meet 2nd segment climb requirements.

18. AIRPORT/RUNWAY ANALYSIS
Takeoff
Limit Codes:
F =Field T =Tire Speed B =Brake Energy V =VMCG * =Obstacle or Level-Off Altitude W=(Tail)Wind Takeoff Not Allowed
These abbreviations will be found on the Airport Analysis pages to tell you what is affecting the weight number on a particular runway.

19. REDUCED-THRUST TAKEOFF
Used when required thrust would be more than what is safely required for takeoff and climb.
The engines assume the OAT (Outside Air Temperature) is higher (using the Assumed Temperature column) and allows the use of a lower thrust (N1) setting.
Saves on engine wear and reduces fuel burn.
Adjusted takeoff speeds and thrust settings found by using performance charts or the FMS.
Safety margins are maintained on performance as the true airspeed at the actual temperature is always less than it would be at the assumed temperature = more runway remaining to stop at V1.
Pilots may still go to full thrust at anytime during takeoff or climb.
Offers a lower noise footprint departing the airport.
The airlines encourage the pilots to do reduced thrust takeoffs after the first flight of the day to save wear and tear on the engines; to save a little fuel, and to reduce the noise footprint over the neighborhoods on the departure path.
The standard is a 10% power reduction.

20. REDUCED THRUST TAKEOFF
Should not be utilized when:
The runway is contaminated or slippery.
There is a temperature inversion or windshear.
The Anti-Skid system is inoperative.
The runway analysis does not allow it.
end

21. TAKEOFF CLIMB LIMIT WEIGHT
After the aircraft has reached the 35 foot height with one engine inoperative, there is a requirement that it be able to climb at a specified climb gradient. The aircraft’s performance must be considered based upon a one-engine inoperative climb up to 1,500 feet above the ground.
The aircraft must clear all obstacles either by a height of at least 35 feet vertically, or by at least 200 feet horizontally within the airport boundaries and by at least 300 feet horizontally after passing the boundaries.
The takeoff profile is broken down into 4 segments with specific operating requirements in each segment.
The Climb Limit Weight allows us to maintain operational compliance with these requirements.

22. TAKEOFF CLIMB LIMIT WEIGHT
Gradient Requirements
This method of calculating climb performance during the various flight path segments is basically a percentage of the horizontal distance traveled in zero wind.
Example: if a 2.4% climb gradient is required, for every 1000 feet that the aircraft travels horizontally, it must climb 24 feet.

23. TAKEOFF CLIMB LIMIT WEIGHT
First Segment : This segment is included in the takeoff runway charts, and is measured from the point at which the aircraft becomes airborne until it reaches the 35-foot height at the end of the runway distance required. Must achieve V2 at 35 ft AGL.
Second Segment : This is the most critical segment of the profile. The second segment is the climb from the 35 ft height to 400 feet above the ground. The climb is done at takeoff power on the operating engine(s) at V2 speed and the first flap retraction occurs. The required climb gradient in this segment is 2.4% for two-engine aircraft, 2.7% for three-engine aircraft, and 3.0% for four-engine aircraft.
The aircraft can be banked up to 15 degrees.
This is the most restrictive of the climb segments due to speed, weight, height above ground, and outside air temperatures.

24. TAKEOFF CLIMB LIMIT WEIGHT
Third Segment : During this segment, the airplane is considered to be above 400 feet AGL and accelerating from the V2 speed to the final climb speed. The remaining flaps are raised and power may be maintained at the takeoff setting up to 5 minutes maximum.
Fourth Segment : This segment continues to 1,500 foot AGL with power set at maximum continuous thrust. The required climb in this segment is a gradient of 1.2% for two-engine airplanes, 1.55% for three-engine airplanes, and 1.7% for four-engine airplanes.

25. TAKEOFF CLIMB LIMIT WEIGHT

26. TAKEOFF CLIMB LIMIT WEIGHT
1500’ AGL
Gross Path
Final Climb
Net Path (Gross - 0.8%)
35’ min
3rd
Accelerate
1.We start with the runway and continue through the four climb segments
... airplane accelerates through V1, rotates at VR and must reach V2 before it is 35 feet above the takeoff surface.
The point at 35 ft is also called “reference zero” because that is when Segment One begins. The airplane should climb out at a speed as close as practical to, but not less than, V2 speed until the selected acceleration height is reached.
The first segment climb ends at gear retraction with a positive climb established.
2.In Segment two...the gear is up; V2 speed constant with a 2.4% min climb gradient.
The acceleration height is chosen by the operator but may not be less than 400 feet.
3. Segment three ... After the airplane reaches the acceleration height of 400 ft, the Third and Final climb segments begin with the transition to enroute climb configuration The operator has considerable latitude in choosing the transition method. One extreme is to climb directly over the obstacle at V2, with takeoff flaps and takeoff thrust. The opposite extreme is to level off at the selected acceleration height, accelerate in level flight to the flaps-up climb speed, and then continue climbing and reducing thrust to MCT. An infinite variety of flight paths between these two extremes may be used. In any event, the flight path chosen to show obstacle clearance must extend to the end of the takeoff flight path.
4. Segment four… The takeoff flight path ends not lower than 1,500 ft for Part 25, and commuter category airplanes.
2nd
35’ min
1st
Min 400’ AGL
Existing
Man-made obstacle
Existing
Terrain obstacle VR V1
35’
Accelerate-stop or
1 Engine take-off distance V2
Take-off Flight Path

27. ACCELERATE/GO
The distance required to accelerate to V1, suffer a failure of the critical engine, & continue the takeoff to 35 ft above the runway surface (V2). This distance must be completed over the rwy.
These definitions may be asked of the student on the FAA computer exam.

28. ACCELERATE/STOP
The distance required to accelerate to V1, suffer a failure of the critical engine, & bring the to a complete stop.
These definitions may be asked of the student on the FAA computer exam.