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KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

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KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

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W831-TOC i 01 MAY 06

TABLE OF CONTENTS 

1.0 INTRODUCTION ............................................................................................... 1-1 

2.0 OBJECTIVES .................................................................................................... 2-1 

3.0 SPECIFICATION AND CERTIFICATION .......................................................... 3-1 

4.0 TERMINOLOGY ................................................................................................ 4-1 

5.0 BASIS FOR PERFORMANCE CHARTS ........................................................... 5-1 

6.0 ENGINE-OUT TAKEOFF PROFILE .................................................................. 6-1 
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1.0 INTRODUCTION 

The KC-10 Mission Planning Performance training consists of two phases of 

instruction. The first phase is strictly academic with interactive computer-based 

training and workshops supplemented by workbooks. There are three CBT 

lessons, seven workbooks, and ten workshops for the Flight Engineers and five 

for the Pilots. Two workbooks, W831 Introduction to KC-10 Takeoff Performance 

and W834 Takeoff and Landing Data, are optional. Information included in the 

two optional workbooks is thoroughly covered in the three CBT lessons. The 

exercises included in the other five workbooks are optional. Questions and 

answers are provided in the workbooks. The second phase of training is done 

during the simulator phase of training, where you will apply procedures taught in 

the academic phase. A TOLD card with different environmental, aircraft and 

runway conditions will be presented for completion for each simulator mission. 

Your instructor will cover each card in detail. 

1.1 SCOPE 

The workbooks follow the Airline Transportation Association (ATA) numerical 

code in the performance manual. ATA code assigns numbers to each system 

and subsystem that all users can use to identify pieces of equipment or systems 

to report malfunctions. These codes are found in the front of the technical 

manuals. Workbooks One and Two mirror the CBT lessons and amplify the 

terminology, definitions, and procedures presented in those lessons. They also 

provide you with a "hard copy" of the material covered in computer-based 

training. Workbooks Three through Seven follow the sections of the performance 

manual from Climb through recovery and Flight/Fuel Planning. The Performance 

Manual, T.O. 1C-10(K)A-1-1 and T.O. 1C-10(K)A-1CL-1 are the primary 

reference sources for the workbooks. Additional background information is 

presented from the following sources: Air Force Instruction (AFI) 11-202, Volume 

3; AFI 11-230; AFI 11-2KC-10, Volume 3; Air Force Manual (AFMAN) 11-217, 

Volume 1, AFMAN 51-9; Federal Aviation Administration Order 8260.3B, US 

Standard for Terminal Flight Instrument Procedures (TERPS); and KC-10 Flight 

Schedule/Computerized Flight/Fuel Plan. 

1.2 INSTRUCTIONS 

This workbook is optional. 
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1.3 BACKGROUND 

When the Air Force decided to augment the KC-135 tanker force, a decision was 

made to purchase an existing airframe rather than design a new aircraft. 

Consideration was given to three existing commercial aircraft: the Boeing 747; 

Lockheed 1011; and the McDonnell Douglas DC-10-30 Freighter. DC-10 was 

chosen. 

It was quite a simple conversion. The aircraft was already equipped with three 

integral wing tanks and an auxiliary or extended range tank in the center 

fuselage. The forward and aft baggage compartments were converted to house 

bladder fuel tanks. This became the Center Wing Tank. There were a few more 

superficial changes, but essentially the KC-10 is a converted DC-10-30 Freighter 

with an air refueling receptacle, boom and centerline drogue. 

The DC-10 had been in commercial service for several years and was fully tested 

and certified by the FAA, so all performance data was certified to FAA standards. 

The test program for the acceptance of the KC-10 was not the same certification 

procedure all over again, but primarily a test of the modifications. The Air Force 

bought the complete package: Aircraft; Flight Manuals; Checklists; and 

Certification Procedures. That makes the KC-10 a "hybrid" animal. Since most 

military aircrews are used to Military Specifications and Terminology, it also 

makes aircraft performance a little more challenging. 

Not only are different procedures used to certify commercial aircraft, many times 

the conditions and definitions used to describe those procedures differ. For 

instance, Ground Minimum Control Speed, or VMCG is defined the same way for 

both civilian and military aircraft; however, the FAA certifies VMCG with a wet or 

icy runway with zero wind, while military aircraft take advantage of the effect of 

nose gear steering and apply crosswind component and RCR. 

Most of the charts you will be using in computing KC-10 takeoff performance are 

compiled directly from the DC-10 charted test performance data. This data was 

reformatted to MILSPEC tolerances where possible. Where data was not 

available, actual flight test data was used. In many cases, notes were added to 

the charts to make the information fit the KC-10 performance criteria. 

This lesson will introduce you to those items, differences in definitions and 

terminology, and their impact on KC-10 Takeoff Performance. 
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2.0 OBJECTIVES

Upon completion of this workbook you will be required to complete a CBT lesson 

followed by a multiple choice CBT test. You must accomplish the test with an 85% 

accuracy. 

A. Identify the differences between specifications used to certify performance 

for commercial and military aircraft. 

B. Identify the definitions for the terminology associated with performance 

calculations. 

C. Identify the criteria used to establish KC-10 performance criteria. 

D. Identify the events and parameters specific to the engine out takeoff 

profile. 
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3.0 SPECIFICATION AND CERTIFICATION

3.1 RUNWAY REQUIRED FOR TAKEOFF-COMMERCIAL CERTIFICATION

Figure 3-1. Three Engine Takeoff. 

All commercial aircraft must satisfy three field length criteria. The first, shown 

above (figure 3-1), is the distance required to accelerate on all engines to attain a 

height of 35 feet at the departure end of the runway, multiplied by 115 percent. 

You will hear this referred to as "Screen Height". All civilian Standard 

Instrument Departures take this into consideration. 

Figure 3-2. Takeoff Continued. 

Second: The distance required to accelerate on three engines to decision speed, 

lose a critical engine, and continue the takeoff to be at a height of 35 feet over 

the end of the runway (figure 3-2). The important thing to remember here is the 

height at the end of the runway. 

ALL ENGINE TAKEOFF DISTANCE TO

CFL

35 FT

X 115%

V LOF

ALL ENGINE ACCELERATION

35 FT

V 1

V LOF

TWO ENGINE ACCELERATION
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Figure 3-3. Takeoff Aborted. 

Third: The distance required to accelerate on three engines to critical engine 

failure speed, lose an outboard engine, and stop in the remaining runway 

distance (figure 3-3). 

ALL ENGINE ACCELERATION STOP DISTANCE 

V1
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3.2 RUNWAY REQUIRED FOR TAKEOFF-MILSPEC CERTIFICATION

Now look at the runway requirement for military aircraft. 

Figure 3-4. Takeoff Continued.

Military Specifications or MILSPECS specify two criteria for the limiting runway. 

The first is distance required to accelerate on three engines to decision speed, 

lose a critical engine, and continue the takeoff and liftoff at the end of the 

runway (figure 3-4). 

Note: While the commercial version places the aircraft at a height of 35 feet over 

the departure end of the runway, the military version will be at zero feet. 

Figure 3-5. Takeoff Aborted.

And secondly, the distance required to accelerate on three engines to decision 

speed, and stop in the remaining runway is considered as a criteria. The runway 

available in both cases being Critical Field Length. 

Complete the following exercise before continuing. 

ALL ENGINE ACCELERATION

V 1

TWO ENGINE

ACCELERATE/STOP DISTANCE

CFL

V R V LOF

ACCELERATION

ALL ENGINE ACCELERATION

V 1

STOP DISTANCE
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3.3 LESSON EXERCISE

1. The KC-10 is a variant of the _____________________________ aircraft. 

2. Terminology and definitions of terms are the two major differences 

between ______________________________________ certification and 

_________________________ certification. 

3. Where possible, the DC-10 flight test data was used in the KC-10. This 

was often accomplished by adding ____________________ to the charts. 

4. One of the major differences in the takeoff distance certification 

procedures between FAA and Military specifications is that the civilian 

version must achieve an engine-out altitude of ______________ feet at 

the end of the runway while the Military version is ______________ feet. 

5. This height at the end of the runway is sometimes referred to as 

____________ height, and is incorporated into commercial standard 

instrument departures. 

6. Military certification procedures require that the aircraft be able to 

accelerate to ______________ speed on __________ engines, lose a 

_________________________, and either ____________ the takeoff or 

_____________ in the ___________ runway. 

7. The distance required to accomplish the events in question 6 is called 

__________________________________. 
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3.4 LESSON EXERCISE ANSWER KEY

1. DC-10-30 Freighter 

2. Military/Commercial 

3. Notes 

4. 35/zero 

5. Screen 

6. Decision/all/critical engine/continue/stop/remaining 

7. Critical Field Length 
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4.0 TERMINOLOGY

4.1 GROUND DISTANCE REQUIREMENTS

Figure 4-1. Critical Field Length (CFL).

Critical Field Length (CFL) is defined as the distance required to accelerate from 

brake release to Critical Engine Failure Speed (VCEF) with all engines operating at 

takeoff power; lose an engine and either continue the takeoff on two engines or stop 

in the same distance (figure 4-1). The KC-10 performance charts optimize the flap 

setting in an attempt to make Critical Field Length equal to Runway Available. If 

performance calculations are followed accurately, the Critical Field Length will 

always be equal to or less than Runway Available. 

Figure 4-2. Lineup Distance.

Lineup distance is defined as the distance required to taxi on to the runway and align 

the aircraft for takeoff. This distance for the KC-10 is 300 feet (figure 4-2). This is a 

nominal distance under ideal conditions. For unusual runway entry requirements or 

180-degree turns on the runway, always use the actual distance required. 
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Figure 4-3. Standard Stressed Overrun.

Stressed Overrun is defined as a paved surface that will support aircraft that are 

authorized to takeoff or land at that airport. The overrun is depicted as light shaded 

areas at the end of each runway. The length and width are provided. This is the 

standard overrun at most airports. Figure 4-3 shows the Airfield Diagram for Travis 

AFB, CA. Notice that runways 03R and 21L have the standard overrun distances. 

OVERRUN 

1000’ X 300’

OVERRUN 

1000’ X 300’
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Figure 4-4. Non-Standard Stressed Overrun.

OVERRUN 

700’ X 200’

NO 

OVERRUN 
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Figure 4-4 is the Airfield Diagram of Norfolk Naval Air Station, Chambers Field, 

Virginia. Notice that Runway 28 has a paved overrun of 700 feet, and Runway 10 

has no overrun. The minimum allowable runway for KC-10 operation is 7,000 feet, 

unless waived by the command authority. For mission accomplishment, if takeoff 

end overruns are available and stressed or authorized for normal operations, they 

may be used to increase the runway available for takeoff. Departure end overruns 

(if stressed and authorized) may also be used for landing if needed. Consult with 

HQ AMC/A37V for suitability guidance. 

4.2 SPEEDS USED IN THE TAKEOFF SEQUENCE

Figure 4-5. Ground Minimum Control Speed (VMCG). 

Ground Minimum Control Speed, or VMCG, is defined as the minimum airspeed at 

which the airplane, while on the ground, can experience a wing engine failure and 

maintain directional control, with takeoff thrust set on the remaining engines, without 

exceeding a lateral deviation of 25 feet from runway centerline (figure 4-5). During 

reduced thrust takeoffs, power on remaining engines may be increased to takeoff 

thrust only after reaching 135 knots (worst case wet/icy VMCG / VR MIN). The KC-10 

charted VMCG is the FAA recognized version, using zero crosswind and a wet/icy 

runway. The KC-10 chart has a note added to allow 10 knots to be subtracted from 

this charted value to account for the benefit of nose wheel steering when the RCR is 

10 or greater. Data are shown for RCR values less than 10, VMCG correction if RCR 

greater than or equal to 10. If RCR is greater than or equal to 10 and no RSC exists 

and crosswind component less than or equal to 10: subtract 10 knots. 

RCR < 10 - NG STEERING NOT EFFECTIVE

FULL RUDDER

INOPERATIVE

25'

V

>_

DEFLECTION

ENGINE

RCR 10 - NG STEERING EFFECTIVE

V MCG
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Figure 4-6. Decision Speed (V1).

Decision Speed, or V1, is defined as that speed used to determine whether to 

continue the takeoff or abort following an engine failure. It is the higher of Critical 

Engine Failure Speed (VCEF) or Minimum Ground Control Speed (VMCG), not to 

exceed Maximum Braking Speed (VMBE). Decision Speed is normally associated 

with an engine failure at or near V1. Decision Speed is usually Critical Engine 

Failure Speed and may not be lower than Ground Minimum Control Speed or higher 

than Maximum Braking Speed. The takeoff is aborted before V1 if a serious 

emergency/loss of thrust occurs because the takeoff may not be achieved in the 

remaining runway. If an emergency occurs after V1 is reached, the takeoff is 

committed because there may not be enough runway remaining to stop (figure 4-6). 

Hence the name, “Decision Speed". See Section 5 of this workbook for an 

explanation of Critical Field Length verses Runway Available. 
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Figure 4-7. Minimum Unstick Speed (VMU).

Minimum Unstick Speed, or VMU, is defined as "that speed at which an aircraft may 

be lifted off without demonstrating unstable flying characteristics". There are no 

charts in the Performance Manual for this speed; however, speeds such as 1.0g 

Stall Speed, Rotate Speed, and Liftoff Speed are based directly on VMU. Take a look 

at Figure 4-8. 

Figure 4-8. Positive Angle of Incidence. 

Many aircraft, such as the C-5, are designed with a positive angle of incidence 

between the wing and fuselage, which generates lift (and drag) throughout the 

takeoff roll (figure 4-8). When the speed is sufficient to generate the required lift, the 

aircraft automatically lifts off. This increased drag however, results in a longer 

takeoff ground roll. 

V MU

a e

V

V

e theta

a alpha

= Relative Wind

= Pitch Attitude

= Angle of Incidence
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Figure 4-9. Neutral Angle of Incidence.

The KC-10 is designed with an almost neutral angle of incidence (figure 4-9). It 

generates very little lift (or drag) during the takeoff ground roll. 

V

e theta

a alpha

e

a

V

= Relative Wind

= Pitch Attitude

= Angle of Incidence

a
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Figure 4-10. 1.0g Stall Speed.

Due to the nearly neutral angle of incidence, the aircraft must be deliberately and 

forcibly rotated from a three point attitude to achieve an angle of attack that will 

produce enough lift for flight. At some point during the rotate sequence, the lift 

produced by the wings will equal the weight of the aircraft (figure 4-10). This is the 

definition of 1.0g Stall Speed and is the basis for all takeoff speeds from rotate 

through V2. This speed is one of two charted stall speeds in the Performance 

Manual. It is a "Power On" stall speed and is considerably higher than the "Minimum 

Stall Speed.” 

> a

LIFT

WEIGHT
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Figure 4-11. Air Minimum Control Speed (VMCA).

Air Minimum Control Speed, or VMCA, is the minimum speed at which an aircraft 

while airborne, can experience a wing engine failure maintain directional control 

using full rudder deflection and not more than five degrees of bank angle (figure 4-

11). This speed is not limiting on the KC-10 with a fully operational rudder system. 

YAWING MOMENT COEFFICIENT

AIR MINIMUM

FROM MAXIMUM USABLE

INDICATED AIRSPEED

5 DEGREES OF BANK

RUDDER DEFLECTION

FROM ASYMMETRICAL THRUST

CONTROL SPEED

YAWING MOMENT COEFFICIENT
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Figure 4-12. Minimum Stall Speed (VS).

Minimum Stall Speed, or VS, is the minimum speed at which an aircraft will cease 

to produce enough lift to sustain flight. This occurs during a period of the stall where 

the lift generated is less than the weight of the aircraft. This is referred as a "Power 

Off" speed. That is: The speed is reduced in increments of one knot per second 

while maintaining altitude. The speed at which the altitude can no longer be 

maintained is the Minimum Stall Speed (figure 4-12). It is the basis for all approach 

and landing speeds. 

Figure 4-13. Rotate Speed (VR).

Rotate Speed, or VR, is that speed at which the KC-10 must be deliberately and 

forcibly rotated from a three point attitude to pitch angle that will produce enough lift 

to sustain flight. This speed is based on 1.0g Stall Speed. The charts are based on 

a four second time frame for this event. This time equates to approximately 800 to 

1,200 feet of runway required from start of the rotate sequence to liftoff (figure 4-13). 

Charted VR has been increased by approximately 8 knots to provide adequate boom 

clearance at rotate. 

SPEED IS REDU CED AT 1 KN OT PER SEC ON D

STALL

1.5 VS 1.4 VS 1.15 VS 1.05 VS 1.0 VS

AP PRO X 1,000'

V R
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Figure 4-14. Liftoff Speed (VLOF).

Liftoff Speed, or VLOF, is the speed at which the aircraft becomes airborne. For 

planning purposes in the KC-10, this occurs at the end of the runway at a 

predetermined pitch angle what will allow continued acceleration to Climbout 

Speed, or V2. This speed was increased the same increment as Rotate. 

Figure 4-15. Climbout Speed (V2).

Climbout Speed, or V2, is defined by the FAA as 115 percent of the charted 1.0g 

Stall Speed. Since Rotate and V2 have both been increased by 8 knots, the KC-10 

Climbout Speed, or V2, always exceeds the FAA minimum requirement. This speed 

is achieved at a height of 50 feet above the ground with the gear handle in the up 

position, and with the flaps and slats in the takeoff configuration (figure 4-15).

V LOF

V LOF

50'

V 2
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Figure 4-16. Climbout Speed 2 or 3 Engine.

The minimum Climbout Speed for the KC-10 is based on V2 for 2 engine climb and 

V2 plus 10 Knots for 3 Engine climb (figure 4-16). These speeds were chosen to 

provide the maximum amount of height for the minimum horizontal distance, or 

simply, the best angle of climb. Since the takeoff data is based on the runway 

available and required climb gradient, this speed will assure the minimum climb 

gradient or the gradient required by an obstacle will be achieved with an engine 

inoperative. Now look at some climb gradient criteria. 

V LOF

50'

V 2

2 ENGINE CLIMB

V LOF

50'

V 2 + 10

3 ENGINE CLIMB
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4.3 CLIMB GRADIENT

Figure 4-17. Climb Gradient.

Climb Gradient is defined as the net vertical height divided by the horizontal distance 

(figure 4-17). You have more than likely used this formula to determine either height 

at a given distance, or distance at a given height. You recall that the minimum 

allowable climb gradient for the KC-10 is 2.5%. Using that formula, at one nautical 

mile, the KC-10 should be at 152 feet. 

152' X 100 = 2.5% 6080 X 2.5% = 152

6080' 

OR 

40:1 

RATIO

Figure 4-18. Gradient = Height/Distance (G=H/D).

First, using the height-divided-by-distance linear equation, you can determine that a 

height of 152 feet in one nautical mile will require a 2.5% gradient; or 152 divided by 

6,080 feet will yield a gradient of 2.5% (figure 4-18). However, take a look at a KC10 climb gradient chart and see why this will not work (figure 4-19). 

GRADIENT = H (HEIGHT)

GRADIENT %

H

D

D (DISTANCE)
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Figure 4-19. Gross Climb Gradient.

Figure 4-19 is an extract of sheet 3 of the Climbout Flight Path series in the 

Performance Manual. Enter this chart with 6,080 feet and apply the most limiting 

flap setting correction. Intersect the 2.5% gradient line, and read the height at the 

left. Notice the height is well below 152 feet. This is because the KC-10 climb 

gradient charts are based on a "gross" gradient and not a "net" gradient.

6,080′

110′
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Figure 4-20. Net Climb Gradient.

Now look at the actual or "net" gradient required to achieve 152 feet in one nautical 

mile (figure 4-20). Again, enter the chart with 6,080 feet and the most limiting flap 

correction and now intersect the desired height of 152 feet. Note that the gross 

gradient required to achieve the required height is 3.5% (based on no tailwind). The 

standard linear equation cannot, under any circumstances, be used to 

152′

6080’ 
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compute KC-10 climb performance. The only acceptable method is to enter the 

charts with the obstacle height and distance from the departure end of the runway 

and use the resulting charted gross gradient to compute all obstacle clearance 

calculations. 

Now take look at the KC-10 Climbout Flight Path (One Engine Inoperative) and 

actual criteria for Obstacle Clearance. 

Figure 4-21. Engine Out Climb Segments.

For the purposes of this discussion, the KC-10 Obstacle Clearance Criteria is 

divided into four areas of consideration: This will cover only the Engine Out 

Profile. 

1. FIRST SEGMENT 

2. SECOND SEGMENT 

3. TRANSITION SEGMENT 

4. FINAL CLIMB SEGMENT 

1. The first segment begins just after liftoff and continues until the landing gear is 

retracted. The speed will vary between VLOF and V2 at 50 feet. 

2. The second segment starts at the point the gear is fully retracted and continues 

until the aircraft reaches Pressure Height for Acceleration. The minimum speed 

for this segment is V2. 

3. The transition segment is the portion of the flight path during which the airplane is 

accelerated in level flight to the VSR. Flaps and slats are retracted as the 

recommended flap and slat retraction speeds are reached. 

4. In the final segment, the airplane climbs at VSR using MCT power with the gear, 

flaps, and slats retracted. 
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Before discussing the KC-10 Climb Segments in detail, take a look at the basis for 

the climb profiles, as far as the FAA is concerned. 

The following paragraphs are extracted from FAA Departure Order 8260.3B, Volume 

4, Departure Procedure Construction. 

GENERAL. 

IFR departure procedures may be designed and published for 

all runways authorized by the approving authority. For civil 

procedures, runway/taxiway separations, and airport obstacle 

free zones (OFZ) must meet the standards in Advisory Circular 

(AC) 150/5300-13, Airport Design, or appropriate military 

directives for military procedures for specified departure visibility 

minimums. 

Departure Obstacle Clearance Surface (OCS) Application. 

The OCS is an inclined surface associated with a defined area 

for obstacle evaluation. The OCS slope is 40:1. This equates to 

152 ft/NM which is expressed as a 2.5% linear climb gradient 

(6080 ÷ 152 = 40). The minimum climb gradient of 200 ft/NM 

also provides for an additional Required Obstacle Clearance 

(ROC) of 48 feet (152 + 48 = 200). The OCS begins at the DER 

at DER elevation. EXCEPTION: Adjust the origin height up to 35 

feet above DER as necessary to clear existing obstacles. 

Evaluate proposed obstacles assuming the OCS origin is at 

DER elevation.

Diverse Departures.

A Diverse Departure is a departure without restrictions to the 

route of flight. At many airports, a prescribed departure route is 

not required for ATC purposes or as the only suitable route to 

avoid obstacles. In spite of this, there may be obstacles in the 

vicinity of the airport that should be considered in determining 

that restrictions to departures are to be prescribed in a given 

sector(s). The areas and surfaces described herein are to be 

used to identify such obstacles. Areas are described by 

bearings and distance from Departure Reference Point (DRP). 

NOTE: Air Force Instruction dictate specific guidance and 

restrictions concerning Diverse Departures. 

 

This directive has much more extensive information on Diverse Departures, but for 

this discussion you need only concern yourself with the following areas; Initial Climb 

Area, Diverse “A” area, and Diverse “B” area. 
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Figure 4-22. Initial Climb Area.

INITIAL CLIMB AREA (ICA). 

The ICA is an area centered on the runway centerline extended used to evaluate 

obstacle clearance during the climb to 400 feet above Departure End of Runway 

(DER) at a minimum climb gradient of 200 ft/NM. 

ICA Baseline (ICAB). 

The ICAB is a line extending perpendicular to the runway centerline ± 500 at DER. It 

is the origin of the ICA. 

ICA End-line (ICAE). 

The ICAE is a line at the end of the ICA perpendicular to the runway centerline 

extended. The splay of 15° and length of the ICA determine its width. 

Area: 

Length. 

The ICA length is normally 2 NM, measured from the ICAB to the ICAE along 

runway centerline extended. It may be less than 2 NM in length for early turns by 

publishing a climb gradient, or a combination of climb gradient and reduction in Take 

Off Runway Available (TORA). The ICA may be extended beyond 2 NM to maximum 

length of 10 NM. A specified altitude (typically 400' above DER) or the interception of 

Positive Course Guidance (PCG) route must identify the ICAE. 

Width. 

The ICA origin is 1,000 feet (± 500 perpendicular to runway centerline) wide at the 

DER. The area splays outward at a rate of 15° relative to the departure course 

(normally runway centerline). 

OCS. 

The OCS originates at the ICAB, normally at DER elevation. Apply the OCS by 

measuring the shortest distance from the ICAB to the obstacle. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-19 01 JUL 13 

 

Figure 4-23. Diverse ”A” and “B” Areas

GENERAL. 

Evaluate diverse “A” and “B” areas to a distance of 25 NM for non-mountainous 

areas and 46 NM for mountainous areas. If obstacles do not penetrate the OCS, 

unrestricted diverse departure may be authorized; publish standard takeoff 

minimums. 

Diverse "A" Area. 

All areas on the DER side of the DRL. Calculate the height of the OCS at any given 

location in the diverse "A" area by measuring the distance from the obstacle to the 

closest point on the centerline of the runway between the DRP and DER, or the 

closest point on ICA boundary lines as appropriate. The beginning OCS elevation is 

equal to the MSL elevation of the ICAE. 

Diverse "B" Area. 

All areas on the Starting Elevation of Runway (SER) side of the DRL. Evaluate 

obstacles in the Diverse "B" area by measuring the distance in feet from the obstacle 

to the DRP. 

Note: Additional information can be found in Air Force Instructions (AFI) and Air 

Force Manuals (AFMAN), e.g. AFI 11-2KC-10 Vol. 3, AFI 11-202 Vol. 3, AFI 11-230, 

and AFMAN 11-217, Vol. 1. Such information can be referenced; instrument 

departure criteria, obstacle clearance requirements, climb gradients, minimum climb 

rates, all engine criteria, one engine inoperative criteria, Special Departure 

Procedures, diverse departures, departure routes, standard instrument departures 

(SIDs), etc. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-20 01 JUL 13 

Figure 4-25. First Climb Segment.

As stated earlier, for the purposes of this discussion, the engine-out climbout flight 

path is broken down into four segments. This is the first segment. A climbout flight 

path is plotted from liftoff to the start of the pressure height for acceleration. The 

minimum plot is based on a 2.5% gradient with two engines at takeoff power, V2 set 

by 50 feet AGL, and flaps and slats in the takeoff configuration. Any object which 

penetrates this plane will be cleared by requiring a higher climb gradient or 

increasing the distance to the obstacle by reducing the runway available. HEIGHT 

AT 50 FEET 

GEAR HANDLE UP AT V2

T.0. FLAP AND SLATS EXTENDED 

10 MILES 

DISTANCE

1500’
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-21 01 JUL 13 

Figure 4-26. Second Climb Segment.

The second segment starts at the point the gear is fully retracted and continues until 

the aircraft reaches Pressure Height for Acceleration. The minimum speed for this 

segment is V2. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-22 01 JUL 13 

Figure 4-27. Transition Segment. 

This segment begins approximately 10 nautical miles from liftoff and continues for 

another 10 miles (figure 4-27). This altitude is 1,500 feet for standard day 

temperatures, and is adjusted up or down as required. At this point, the aircraft is 

leveled off and allowed to accelerate to a point where the flaps and slats are 

retracted. The aircraft is flown in the clean configuration at slat retract speed. No 

object shall penetrate this pressure height for acceleration. If an obstacle exists 

within this envelope, the obstacle height becomes the pressure height for 

acceleration. HEIGHT 

DISTANCE
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-23 01 JUL 13 

Figure 4-28. Final Climb Segment.

The final segment begins at the end of the transition segment with the aircraft in a 

clean configuration at slat retract speed (figure 4-28). The airplane climbs at VSR

using MCT power with the gear, flaps, and slats retracted. The purpose of the 

transition segment was to set up this final climb segment in order to clear distant 

obstacles. This schedule and flight path is a procedure that will assure that distant 

obstacles will be cleared. 

Please complete the following exercise before continuing. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-24 01 JUL 13 

4.4 LESSON EXERCISE

 1. Since the KC-10 performance charts optimize the flaps to the length of 

the runway, the critical field length will always be equal to or less than 

the _________________________________. 

 2. The lineup distance for the KC-10 is ___________ feet. 

 3. You are planning a takeoff on a runway that is 9,700 feet long with 500 

feet of paved overrun. What is the runway available for takeoff? 

Ans.___________________. 

 4. VMCG is the speed at which directional control can be achieved using 

full rudder deflection and not deviate more than __________ feet from 

runway centerline. 

 5. When the RCR is 10 or greater, subtract ___________ knots from 

charted VMCG to account for the effect of 

_________________________________. 

 6. Decision speed, or V1, is usually VCEF but not lower than ___________ 

or higher than _______________. 

 7. The speed at which an aircraft may be lifted off without displaying 

unstable flying characteristics is called 

_______________________________ , and is the basis for 1.0g Stall 

Speed. 

 8. All takeoff airspeeds are based on Power On _______________ stall 

speed. 

 9. The KC-10 is not VMCA limited as long as all 

________________________ are operational. 

10. Minimum Stall Speed is a much lower speed than 1.0g Stall Speed. It 

is used as a basis for _____________ and __________ speeds. 

11. A ___________ second time frame is allocated to rotate the aircraft 

from a three-point attitude to a pitch angle for takeoff. 

12. All takeoff speeds have been increased by __________ knots over 

charted test data to allow for adequate 

______________________________. 

13. V2, or Climbout Speed, should be achieved at a height of _________ 

feet above the takeoff elevation. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-25 01 JUL 13 

14. Climbout speeds were chosen to approximate the best ___________ 

of climb in order to achieve the highest ___________ distance for the 

minimum horizontal distance traveled. 

15. The minimum climb gradient required for the KC-10 is _________ 

percent. 

16. This gradient is a __________ gradient and not a net gradient; 

therefore, the conventional gradient formula cannot be used to 

determine a given height for a given distance. 

17. The Obstacle Clearance Surface slope is a ________ to ________ 

ratio. 

18. This height equates to ________ feet per nautical mile or a climb 

gradient of ______ percent. 

19. Any obstacle that lies within __________ degrees of the Initial Climb 

Area (ICA), and penetrates the obstacle clearance surface (OCS) shall 

be identified on the departure. 

20 The standard geometric pressure height for acceleration is _______, 

and is adjusted up or down for non standard ________________. 

21. After leveling off at the pressure height for acceleration, the aircraft is 

allowed to accelerate to ____________________________ where the 

____ _________________ are retracted; then to 

__________________________________ where the __________ are 

retracted. The aircraft is now climbed at 

_____________________________ until all obstacles are cleared or 

the minimum altitude for enroute operations is reached. 

22. The Pressure Height for Acceleration level off and clean up is the only 

way to insure that ___________ obstacles are cleared. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

CH 5

W831-04 4-26 01 JUL 13 

4.5 LESSON EXERCISE ANSWER KEY 

1. Runway Available 

2. 300 

3. 9,400 

4. 25 

5. 10/nose wheel steering 

6. VMCG/VMBE

7. Minimum Unstick Speed 

8. 1.0g 

9. Rudder Systems 

10. Approach/Landing 

11. 4 

12. 8/boom clearance 

13. 50 

14. angle/vertical 

15. 2.5 

16. gross 

17. 40/1 

18. 152/2.5 

19. 15 

20. 1,500 feet/temperatures 

21. flap retract speed/flaps/slat retract speed/slats/slat retract speed 

22. distant 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-1 01 JUL 13 

5.0 BASIS FOR PERFORMANCE CHARTS

Up to this point the discussion has been on concept, methodology, definitions 

and procedure. Now you will cover the criteria used to establish the basis for the 

charted data in the performance manual. You will look at four areas affecting 

performance calculations. First you will cover engine data and the relationship 

between thrust and temperature, pressure altitude, and speed. Next you will 

define the environmental envelope; establish takeoff thrust requirements; and 

finally; cover the methods for determining reduced power takeoff criteria.

5.1 ENGINE DATA

0 1234 5678 9 32

34

36

38

40

42

44

46

48

50

52

54

56

ALTITUDE, 1000 FT

-50M

-45A

-50C

-50A

-6D1

-6D

-45B

IDEAL THRUST,

TAKEOFF THRUST VARIATION WITH ALTITUDE

1000 LB

AT FLAT RATE TEMPERATURE

-CF6-50C2*

*DESIGN TEST DATA

Figure 5-1. Constant Temperature Varied Altitude.

The KC-10 is equipped with three General Electric CF6-50C2 engines. This 

engine is a variant of the basic 50 series that has been in service for many years. 

Figure 5-1 shows the relationship of thrust with altitude at a constant 

temperature. 

Note that the thrust decreases as a function of altitude if the temperature remains 

constant. All performance charts in the performance manual make use of this 

linear decrease. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-2 01 JUL 13 

ENGINE CF6-50C2

SEA LEVEL STATIC, UNINSTALLED 

TAKEOFF 

 IDEAL THRUST (LB) 

 REAL THRUST (LB) 

 SFC (IDEAL)

* 52,500 

51,800 

.394

MAX CONTINUOUS 

 REAL THRUST (LB) 

 SFC

46,300 

.385

35,000 FT M=0.85, UNINSTALLED

MAX CLIMB 

 REAL THRUST (LB) 

 SFC

11,500 

.664

MAX CRUISE 

 REAL THRUST (LB) 

 SFC

10,800 

.654

* DESIGN TEST DATA 

Figure 5-2. Constant Altitude Temperature Varies. 

The thrust also varies as a function of temperature at a constant altitude. One of 

the characteristics of a flat rated engine is that it will produce a predictable, 

constant amount of thrust over a wide range of environmental conditions. Figure 

5-2 shows the thrust and specific fuel consumption for various power settings. 

Temperature is the second leg of the power equation. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-3 01 JUL 13 

Figure 5-3. Constant Altitude Constant Temperature Velocity Increase.

This figure shows the relationship between increased velocity, or airspeed and 

thrust. Note that the available thrust decreases as the MACH increases. This is 

a very small variant during the takeoff sequence; however, it becomes a player at 

climb and cruise airspeeds. All performance charts are built around these three 

factors: Temperature, Altitude and Speed. 

TAKEOFF THRUST VARIATION 

WITH MACH NO. 

REAL NOZZLE

THRUST 

1000 LB 

MACH NO.

CF6-6D 

CF6-6D1 

CF6-45A/B 

CF6-50M 

CF6-50E

CF6-50C 

CF6-50A 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-4 01 JUL 13 

Figure 5-4. Thrust VS. N1 RPM.

As you have seen, the thrust available for a given set of conditions is built into 

the performance charts. Unlike many other aircraft, you do not use a "Thrust 

Factor", "Takeoff Factor" or for that matter, any other factor except temperature 

and pressure altitude to determine performance calculations. The N1 RPM is the 

sole measure of thrust in the KC-10. In the takeoff range, 1 percent N1 equals 

about 1.8 percent of the available thrust for a given set of conditions. 

Now take a look at the performance factors of a "Flat Rated Engine". 

RPM
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-5 01 JUL 13 

5.2 ENVIRONMENTAL ENVELOPE

BREAK POINT:

FLAT-RATED THRUST

NOTE:

TEMPERATURE

MAXIMUM CERTIFIED TEMPERATURE

THRUST N1

THERE IS A SIMILAR

LINE FOR EACH

ALTITUDE UP TO THE

MAXIMUM CERTIFIED

ALTITUDE

REDUCED THRUST

PERMITTED

Figure 5-5. Flat Rated Engine.

The CF6-50 engine is flat rated. It will produce a constant amount of thrust at a 

given altitude as a function of temperature. In figure 5-5 you see one altitude line 

as would be depicted on a performance chart or the environmental envelope. 

There is a line from the bottom of the envelope to the maximum certified altitude. 

From the minimum temperature to the break point, the thrust will remain 

constant. At the break point the thrust will decrease as a function of temperature 

until the maximum certified temperature is reached. 

14

12

10

8

6

4

2

0

-1

-54 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

STANDARD DAY

BREAK POINT TEMPERATURE

Figure 5-6. Break Point VS. Altitude.

Figure 5-6 adds the remaining lines with the break point temperature for each 

line. Note that the break point remains the same from -1,000 feet to an altitude 

of 2,400 feet. From here the temperature decreases until it reaches 5,000 feet. 

It now remains the same up to the maximum certified altitude of 14,000 feet. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-6 01 JUL 13 

Figure 5-7. Standard Day + 40.

Figure 5-7 shows the standard day plus 40 degree line plotted against the 

standard day temperature. It starts at the maximum allowable ambient 

temperature of 50 degrees Celsius, remains constant until 2,400 feet. It then 

parallels the standard day temperature line until the maximum certified altitude of 

14,000 feet is reached. 

14

12

10

8

6

4

2

0

-1

-54 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

M AXIMU M CER TIFIED

14,000'

STANDARD DAY TEM P + 10 DE G.

Figure 5-8. Maximum Certified Temp + 10.

Figure 5-8 depicts the last line on the temperature vs. Altitude graph. This graph, 

and all the charts in the takeoff section of the performance manual, are extended 

by 10 degrees to allow assumed temperature to be used in computing reduced 

power takeoffs. Now look at the environmental envelope. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-7 01 JUL 13 

Figure 5-9. The Environmental Envelope.

Here is the complete Environmental Envelope (figure 5-9). The KC-10 is certified 

to operate within this range of temperatures and altitudes. 

1 ALTITUDE: -1,000 FEET TO 14,000 FEET. 

2 TEMPERATURE: -54 TO 50 DEGREES C. NOT TO EXCEED STD 

DAY + 40 ABOVE 2,400 FEET. 

3 BREAK POINT: DEFINES THE LOWER LIMIT FOR ASSUMED 

TEMPERATURE. 

4 MAX TEMP + 10: DEFINES THE UPPER LIMIT FOR ASSUMED 

TEMPERATURE. 

These temperature and altitude grid lines are repeated in each performance 

chart that deals with temperature and pressure altitude as a function of thrust 

available. Operation outside of this envelope is not permitted. Take a look at 

one of the charts in the takeoff section of the performance manual. 

14

12

10

8

6

4

2

0

-1

-54 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

STANDARD DAY

ENVIRONMENTAL 1

4

2

STANDARD DAY 3

FLAT RATED THRUST

2

<

>

<

1

BREAK POINT TEMPERATURE

PLUS 40 DEG.

ENVELOPE PLUS

10 DEG.
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-8 01 JUL 13 

Figure 5-10. Chart Design.

Figure 5-10 is a replica of Sheet 5 of the Climb Gradient Limiting Weight series. 

All charts that are entered with temperature and pressure altitude have these 

same grids. You should recall the Environmental Envelope plots. Here are 

those same plots with the altitude grids reversed and the same lines plotted on 

the performance chart. 

Now look at Thrust Settings for Takeoff. 

Reduced power 

takeoffs permitted 

inside this area

Heavy line represents Break Point of Environmental Envelope

and the Minimum Assumed Temperature as a function of Altitude.

Dashed line represents Upper limit or Maximum Assumed Temperature as a 

function of Altitude. (Environmental Envelope + 10°).
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-9 01 JUL 13 

5.3 POWER REQUIREMENTS

Conditions permitting, full rated thrust is seldom used for normal operations. 

Where possible, thrust is reduced to match the environmental and weight 

conditions for the assigned mission. Here are the conditions that require a full 

power takeoff: 

Reduced thrust usage is not permitted if: 

■ RCR value is less than 10. 

■ RSC is used for TOLD computations. 

■ The anti-skid braking system or one main gear wheel brake is inoperative. 

■ One center gear wheel brake is inoperative and takeoff gross weight is greater than 460,000 pounds. 

■ Headwinds are used for mission accomplishment. 

■ Suspected windshear is reported. 

■ Commercial Type II deicing/anti-icing fluid has been applied. 

NOTE 

The takeoff performance of the aircraft is not affected by the application of MIL 

SPEC or Commercial Type IV deicing/anti-icing fluid. 

Figure 5-11. Power Set by 80 Knots.

In order to guarantee charted takeoff performance, takeoff power must be 

established between 40 and 80 knots. After 80 knots, no adjustments are made 

except to prevent engine overboost. Takeoff Rated Thrust is permitted up to 

2,000 feet above the takeoff altitude, not to exceed five minutes for three engine 

operation and 10 minutes with an engine out (figure 5-11). These limits are valid 

for full and reduced power takeoffs. 

Before you continue, take a look at the relationship between temperature, throttle 

position, and N1 RPM. 

POWER SET BY

5 MINUTES - 3 ENGINES

10 MINUTES - 2 ENGINES

FIELD ELEVATION

2,000'

80 KNOTS
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-10 01 JUL 13 

Figure 5-12. Throttle, Temp, and RPM.

As stated before, a flat rated engine is capable of producing a given amount of 

thrust over a wide range of environmental conditions. Because of this, it is 

capable of producing an enormous amount of power at very low ambient 

temperatures. The area of the chart (figure 5-12) bordered in heavy black lines 

represents the area where full throttle is required to produce the predicted thrust. 

From the bottom of the environmental envelope to the maximum certified altitude 

as a function of temperature, the thrust will remain the same for a given altitude 

from -54 degrees C. to the Break Point Temperature. 

At the Break Point, full throttle will be reached. From that point, up to the 

maximum allowable ambient temperature, the thrust and N1 RPM will decrease. 

This area is shaded and inside the thick outlined area in Figure 5-12 and in the 

blackened area in Figure 5-13. 

14

12

10

8

6

4

2

0

-1

-54 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

AREA OF CONSTANT POWER -

FULL

N1

PART FULL

BREAK POINT

N1

PART THROTTLE

THROTTLE

AREA

THROTTLE THROTTLE
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-11 01 JUL 13 

Figure 5-13. Throttle, Temp, and RPM.

Figure 5-13 depicts the Sea Level altitude line with N1 RPM and representative 

throttle positions for a series of temperatures: 

(1) -30 Deg C. 101.9% 

(2) -20 Deg C. 103.9% 

(3) 0 Deg C. 108.0% 

(4) +20 Deg C. 111.9% 

(5) +30 Deg C. 113.7% - Breakpoint 

(6) +50 Deg C. 108.4% 

Note that as the temperature increases, the throttle and RPM increase 

proportionally until the break point is reached. From the break point to the 

maximum allowable temperature, the thrust and RPM decrease. 

Now look at the concept, methodology, and procedures involved in computing 

reduced thrust takeoffs. 

14

12

10

8

6

4

2

0

-1

-54 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

101.9 103.9 108.0 111.9 113.7 108.9

(1) (2) (3) (4) (5) (6)

BREAKPOINT

RPM

DECRE ASE
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-12 01 JUL 13 

5.4 REDUCED POWER TAKEOFFS

Many years ago, several airlines and aircraft manufacturers commissioned a 

feasibility study to determine the maintenance cost savings if reduced takeoff 

thrust were used in day-to-day operations. Baseline data were developed and 

several models were sent to the FAA for approval. The FAA approved two 

procedures and set down restrictions where, in their opinion, safety was a factor. 

The FAA approval was based in part, on the following factors: 

● Thrust may not be decreased more than 25 percent of takeoff rated thrust. 

● The operator must establish a procedure to identify an engine incapable of 

producing takeoff rated thrust. 

● The operator must develop procedures to assure that safety is not 

compromised, and submit those plans to the FAA for approval prior to 

implementing such procedures. 

There are two approved methods for determining reduced power for takeoff. 

One is a flat percentage of available thrust, based on predetermined airfield data, 

and the other is based on the amount of thrust available in excess of the amount 

required, based on aircraft and environmental conditions. 

● Flat Percentage Based on Airfield Analysis: 

Limited Use. 

Not Valid for all Stations. 

Used only on a Dry Runway. 

Does not make use of all Excess Thrust Available. 

Only Two Options--Full Derate or No Derate. 

● Based on Environmental and Aircraft Conditions: 

Totally Flexible. 

Use at any Station. 

Maximum Use of Excess Thrust. 

Always within FAA Tolerances. 

Allows for Partial Reductions. 

The KC-10 uses the second method. It is based on a simple argument: If the 

maximum allowable gross weight for takeoff is based on temperature and 

pressure altitude, then for every pound weight less than maximum there is a 

temperature at which that gross weight would be the maximum allowable. This is 

called Assumed Temperature and is the basis for reduced thrust takeoffs in the 

KC-10. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-13 01 JUL 13 

Figure 5-14. Thrust Reduction VS. RPM.

Figure 5-14 illustrates power reduction based on assumed temperature. In this 

case the OAT is 30 degrees C. at Sea Level. The performance charts tell you 

that with these conditions the maximum temperature would be 50 degrees C. 

This would reduce the N1 RPM by 8.5% for a net thrust decrease of 15%. 

 

Now take a look at the charts involved in determining the Maximum Allowable 

Takeoff Gross Weight, for the existing temperature, or the maximum allowable 

temperature for the existing gross weight. 

0

0

3 0

1

2

3

4

5

6

7

8

9

1 0

1 1

1 2

3 .4

3 5

* *

7 .6

4 0

1 1. 2

4 5

* * * *

1 5. 0

5 0

1 8.4

5 5

*

* * *

*

6 0

2 0. 2

THRUST R EDUCTION - %

THR U ST RED U C TION = DE LTA N 1 (%) X 1.8

CO NDITIONS :

ENGINES:

A M BIE NT TEM P E RATUR E:

P RES SU RE AL TITU DE:

CF6 -50 C2

3 0 DEG . C.

SEA LEVEL

N 1

R

P

M

%

A SS UMED TE MPE RAT URE

8.5%

 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-14 01 JUL 13 

Figure 5-15. Maximum Allowable Takeoff Gross Wt.

5° RALW 504.0 

18° FLAP SETTING 

MTOGW 544.0 

RA = 10,000’ EFL = 9,750’ 

25° CGLW 518.0 

20°C 

MAXIMUM TAKEOFF GROSS WEIGHT AT OPTIMUM TAKEOFF FLAP SETTING 

RCR = 23 to 18 / WITH REVERSE THRUST 

REDUCED THRUST TAKEOFF 

20°C 

SHEET 1 SHEET 2 SHEET 3 SHEET 4 SHEET 5 

UNCORRECTED 

CGLW 524.0 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-15 01 JUL 13 

Figure 5-15 depicts a series of five charts in the Takeoff Section of the 

Performance Manual. Sheets one and two yield a runway available gross weight 

at five degrees of flaps. Sheets five and four yield a climb gradient limiting 

weight at 25 degrees flaps. Sheet three converts these weights to a Flap Setting 

and Maximum Allowable Takeoff Gross Weight. The conditions yield a Maximum 

Weight of 544,000 pounds at a Flap Setting of 18 degrees. If the actual gross 

weight of the aircraft is less than the MTOGW, then there is excess thrust 

available. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-16 01 JUL 13 

Figure 5-16. Maximum Allowable Temperature VS. Weight. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-17 01 JUL 13 

Using the same set of charts, follow the flap line down to intersect the actual 

takeoff gross weight (figure 5-16). Parallel the weight grids to the RALW and 

CGLW at 5 degrees and 25 degrees respectively. Using this RALW enter chart 2 

and intersect the altitude line. Read the Temperature at the bottom of the chart. 

In this case it is 47 degrees. Enter sheet 4 with the CGLW and apply the same 

conditions. Continue on to sheet 5 and intersect the altitude line and read the 

temperature at the bottom. In this case it is 44 degrees. The lowest of these two 

temperatures becomes the Assumed Temperature and is used for all takeoff 

computations with the exception of Pressure Height for Acceleration. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-18 01 JUL 13 

Figure 5-17. Area where Reduced Thrust is Permitted. 

Here is the Environmental Envelope again (figure 5-17). The shaded area 

represents the limits of assumed temperature as a function of altitude. The 

assumed temperature may not be less than the break point temperature, or 

higher than the environmental envelope plus 10 degrees. 

14

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8

6

4

2

0

-1

-54 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

STANDA RD DAY

FLAT RATED THRUST

STANDARD DAY

ENVIRO NMENTAL

2

1

4

5

3

5

4

3

2

1

NOTE:

PRESSURE ALTITUDE FROM MINUS 1,000 TO 14,000 FT

TEMPERATURE FROM MINUS 54 TO 50 DEGREES C

AMBIENT TEMPERATURE MAY NOT EXCEED STANDARD DAY PLUS

40 DEGREES C ABOVE 2,400 FT PRESSURE ALTITUDE

THE ASS UMED TEMPERATURE MAY NOT BE LESS THAN THE

FLAT-RA TED BREAK POINT TEMPERATURE

THE ASS UMED TEMPERATURE MAY NOT EXCEED THE

ENVIRONMENTAL ENVELOPE BY MORE THAN 10 DEGREES C

PLUS 40 DEGREES

ENVELO PE PLUS

10 DEGREES

BREAK POINT TEMPERATURE
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance

CH 5

W831-05 5-19 01 JUL 13 

Figure 5-18. Assumed Temp. Limits on Charts.

The same information is available on any chart in the performance manual that 

has a temperature and altitude grid (figure 5-18). Minimum assumed temperature 

is where the altitude line "bends"; The maximum assumed temperature is where 

it "ends". 

Reduced power 

takeoffs permitted 

inside this area

Heavy line represents Break Point of Environmental Envelope

and the Minimum Assumed Temperature as a function of Altitude.

Dashed line represents Upper limit or Maximum Assumed Temperature as a 

function of Altitude. (Environmental Envelope + 10°).
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Figure 5-19. Runway Available Equals Critical Field Length (RA = CFL).

One other point before you finish this section. Many aircrews are reluctant to 

perform reduced power takeoffs at any gross weights above some arbitrary figure 

that is within their comfort zone. This is mainly due to a misconception. It is said 

that reduced power takeoffs make every takeoff a "max effort", because when 

power is reduced, Critical Field Length becomes Runway Available. For 

example, if the ambient temperature were 15 degrees and the assumed 

temperature were 50 degrees, a check of the CFL charts would agree that RA = 

CFL, providing you enter the chart with 50 degrees. 

A LL E N G IN E A C CE LE R A T IO N

V 1

TW O ENGINE

A C C E LE R A T E /S T O P D IS TA N C E

CFL

V R V LOF

RA = 10,000'

C FL = 10 ,00 0'

ASS UM ED TE MP ER ATU R E 50E

AM BIEN T T EM PER AT U RE 15 E

R UNW A Y

ACCELERATION
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ASSUMED 

TEMP 

7 30°

6 35°

5 40°

4 45°

3 50°

2 55°

1 60°

AMBIENT TEMP 

15°

15°

15°

15°

15°

15°

15°

Figure 5-20. Runway Available > Critical Field Length (RA > CFL).

There is an inherent "pad" or safety margin that results from the fact that the 

aircraft and engines are operating in the actual ambient temperature, and NOT 

in the assumed temperature. Since you are basing all speeds and distances 

on the assumed temperature, there is always additional runway available that is 

directly proportional to the spread between actual and assumed temperature. 

Figure 5-20 shows that relationship of additional runway available as a function 

of the difference in Actual and Assumed Temperature. The difference is greatest 

at the highest spread and decreases as assumed and actual temperatures 

converge.

ASUMED TEMP 

DISTANCE 
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CFL = RA

30 30

15E

CFL < RA

2

1

3

Figure 5-21. Assumed VS. Actual Temp. 

Here is another way of looking at the same thing (figure 5-21). The temperature 

at the left is the ambient temperature and the temperature at the right is 

assumed. As the temperatures become closer, until at some point they are 

equal. When the Assumed Temperature and the Actual Temperature are the 

same, then reduced thrust is TRT and Runway Available will equal Critical Field 

Length. 

1 AS AMBIENT TEMP APPROACHES 

2 ASSUMED TEMPERATURE 

3 THE RA APPROACHES CFL 
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5.5 LESSON EXERCISE

 1. The KC-10 is equipped with General Electric CF6-50C2 engines. They are 

flat rated and the total thrust output varies with __________________, 

________________________________, and ___________. 

 2. The engine instrument that shows the power output of the engines is the 

________ indicator. 

 3. A flat-rated engine will produce a given amount of thrust over a wide range of 

altitudes as a function of ___________________. 

 4. At a given altitude, the thrust will remain the same up to the ___________ 

______________ temperature, then decrease proportional to the 

temperature. 

 5. Above 2,400 feet, the maximum allowable ambient temperature is standard 

day plus ___________ degrees. 

 6. The temperature grids in the performance manual exceed the environmental 

envelope by __________ degrees. This is to allow for ________ power 

takeoffs. 

 7. The environmental envelope altitude grids are from __________ feet to 

___________ feet. 

 8. The environmental envelope temperature grids are from ___________ to 

__________ degrees, not to exceed standard day plus 40 degrees. 

 9. Conditions permitting, full power takeoffs are seldom used. Regardless of 

the type of takeoff being accomplished, takeoff power must be set prior to 

________ knots. 

10. As the temperature increases from the bottom of the envelope, the N1 RPM 

will increase until the _____________________________ is reached. At that 

point, the N1 RPM will decrease as a function of _______________. 

11. The FAA approves reduced power takeoffs up to _________ percent. 

12. The KC-10 uses the ____________________________ method for reduced 

power takeoffs. 

13. The power setting for a reduced power takeoff is based on the lowest of 

_____________________________________ temperature or ___________ 

_______________________ temperature. 
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14. The _____________________ temperature is the minimum allowable 

assumed temperature. 

15. The Maximum Allowable Assumed temperature is the environmental 

envelope plus _________ degrees. 

16. The same information found in the Environmental Envelope can be found on 

any takeoff performance chart that has an ________________ and 

_____________ grid. 

17. When making a reduced power takeoff, the critical field length will always be 

equal to or less than runway available; the difference being the spread 

between the __________ temperature and the _____________ temperature. 

18. The difference between the charted performance during a reduced power 

takeoff and the actual performance is because the aircraft and engines are 

operating in the actual temperature while the distance and speed charts are 

entered with the ___________ temperature. 
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5.6 LESSON EXERCISE ANSWER KEY 

 1. temperature/pressure altitude/velocity 

 2. N1 RPM 

 3. temperature 

 4. break point 

 5. 40 

 6. 10/reduced 

 7. -1,000/14,000 

 8. -54/50 

 9. 80 

10. break point temperature/temperature 

11. 25 

12. assumed temperature 

13. runway available limiting/climb gradient limiting 

14. break point 

15. 10 

16. altitude/temperature 

17. assumed/actual 

18. assumed 
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6.0 ENGINE-OUT TAKEOFF PROFILE

 This is the final subject in this workbook. It covers the engine-out climb profile 

from lineup to the end of the pressure height for acceleration. You will use this 

profile and the associated events to expand and amplify the terms and definitions 

described in the previous segments. You will cover the balanced field concept; 

determine the type of takeoff required for the conditions; compute obstacle 

distance and height; define the best speed for engine-out obstacle clearance; 

and cover the concept of the pressure height for acceleration, to include the 

effect of obstacles. 

Figure 6-1. Engine Out Profile.

The following examples will use this profile as a visual reference to discuss each 

event in the takeoff sequence (figure 6-1). Where speeds and distances are a 

factor, the values for a brake release gross weight of 590,000 pounds, standard 

day conditions for sea level, and a runway available of 10,000 feet. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

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6.1 BALANCED FIELD CONCEPT 

Figure 6-2. Balanced Runway Concept.

The KC-10 "Maximum Takeoff Gross Weight at Optimum Takeoff Flap Setting" 

charts attempt to balance the runway required to accelerate to decision speed, 

lose a wing engine, and either continue the takeoff on two engines or stop in the 

same distance. That distance is Critical Field Length. There are 200 possible 

flap settings for takeoff; however, only one will yield a maximum gross weight 

that will satisfy the runway available limiting weight and the climb gradient limiting 

weight. 

OPTIMIZATION OF 

TAKEOFF FLAP SETTING 

ALLOWABLE 

TAKEOFF REGION 

GROSS WEIGHT 

ALL ENGINE ACCELERATION 

CFL

STOP 

OR 

CFL

VCEF

ALL ENGINE ACCELERATION TWO ENGINE 

ACCELERATION 

VCEF 

VLOF 
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6.2 TYPES OF TAKEOFFS 

Figure 6-3. Static Takeoff.

A static takeoff may be accomplished if conditions permit. The procedure is to 

apply the brakes, advance the throttles to the approximate takeoff power setting, 

release the brakes, and establish the final power adjustment prior to 80 knots. 

The wind direction and velocity must be within the designated area of the Wind 

Component - Takeoff chart (figure 6-4). 
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Figure 6-4. Rolling Takeoff.

Crosswind disturbs the engine inlet airflow, especially when the brakes are set 

and takeoff power is applied. Because of this, a rolling takeoff must be 

performed if the wind direction is 45 degrees off runway heading or the crosswind 

component exceeds 23 knots. The rolling takeoff takes advantage of the forward 

momentum gained during taxi-on to the runway. As the aircraft is aligned for 

takeoff, the throttles are smoothly advanced to takeoff power. Takeoff power has 

to be set at 80 knots, if takeoff power is not set by 80 knots, charted takeoff 

performance may not be achieved (figure 6-4). 

TAKEOFF POWER SET: BRAKES RELEASED – POWER SET – 80 KNOTS 
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Figure 6-5. Lineup Distance.

The aircraft requires a minimum of 300 feet of runway for lineup (figure 6-5). This is a 

nominal distance when the aircraft is taxied into position from a point at the beginning of 

the runway. When unusual circumstances exist, such as a 180 degree turn or another 

entry point, then actual distance required should be used. This line-up distance is 

subtracted from the runway length or Max Liftoff Point (SDP) to determine runway 

available for takeoff. 

Figure 6-6. 80 Knots Power Set. 

 

Figure 6-6. 80 Knots Power Set 

Regardless of the type of takeoff being accomplished, the Pilot Not Flying will call "80 

Knots" and the Flight Engineer will ensure takeoff power is set and state "Power Set". 

The next event is Decision Speed, or V1. 

VSR

MCT 

VCEF

(ENGINE FAILURE) V2

300’ 

“EIGHTY KNOTS, 

POWER SET” 
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Introduction to KC-10 Takeoff Performance 

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W831-06 6-6 01 JUL 13 

6.3 DECISION SPEED/TIME 

Figure 6-7. Decision Speed (V1).

Decision Speed (V1) is the higher of Critical Engine Failure Speed (VCEF) or Ground 

Minimum Control Speed (VMCG), not to exceed Max Braking Speed (VMBE). In this case, 

VCEF is Decision speed, or 163 knots. 

Figure 6-8. Decision Sequence.

At Decision Speed, the Pilot has three seconds of reaction time from an engine failure 

to make the abort decision. Because number two engine is centerline mounted, two 

ENG FAIL lights are installed on the glare shield to alert the crew if an engine fails 

during takeoff ground roll. The system is armed when the N1 is advanced past 85% and 

is activated when an 11% difference or greater is detected. At V1, the aircraft is 

accelerating at approximately 275 feet per second and will cover about 825 feet. 

 HIGHER OF VMCG OR VCEF 

 NOT TO EXCEED VMBE

 

3 SECONDS FROM V1 WITH 

TWO ENGINE ACCELERATION 

ACCELERATE STOP DISTANCE 

ALL ENGINE ACCELERATION STOP DISTANCE 
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Introduction to KC-10 Takeoff Performance 

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Figure 6-9. Abort Sequence.

Once the decision is made to abort the takeoff, there is a 1.1 second time frame 

of constant speed where the throttles are pulled to idle, maximum anti-skid 

braking is applied, full reverse thrust applied, and the spoilers are deployed 

(figure 6-9). This will add another 300 feet to the total distance. The abort 

decision sequence, in this case, required approximately 1,125 feet of runway. 

The aircraft will now stop in the remaining runway. 

Figure 6-10. Takeoff Continued.

If the decision is made to continue, the Pilot will maintain directional control using 

rudder and nose wheel steering while the aircraft accelerates to Rotate Speed or 

187 knots. 

ALL ENGINE ACCELERATION STOP DISTANCE 
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W831-06 6-8 01 JUL 13 

When performing a reduced thrust takeoff and an asymmetric 

power condition results from loss of a wing engine; advancing 

power to takeoff rated thrust on remaining engines prior to 

reaching 135 KIAS may result in insufficient lateral control and 

aircraft may depart the confines of the runway since VMCG is 

calculated using assumed temperature. 

Figure 6-11. WARNING.

The above WARNING (figure 6-11) applies only to reduced power takeoffs. 135 

knots is chosen because it is the worst case, wet/icy VMCG / VR MIN. It would not 

apply to Rotate because VR MIN guarantees lateral control. 

Figure 6-12. Rotate Speed (VR).

The next event is Rotate Speed (VR). This speed must be equal to or greater 

than VR MIN. VR MIN is the wet/icy charted VMCG. In this case charted VR is 179 

knots. The charted VR speed, which is 105% of minimum unstick speed (VMU), 

has been increased by 8 knots above the basic DC-10 rotate speed to allow 

adequate boom clearance at rotate. 
KC-10 Aircrew Training System 

Introduction to KC-10 Takeoff Performance 

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W831-06 6-9 01 JUL 13 

Figure 6-13. Distance During Rotate.

At VR, a four second time frame (figure 6-13) is allocated to allow the aircraft to 

be rotated from a three point attitude to an angle of attack that will allow 

continued acceleration through minimum unstick speed (VMU) to liftoff speed 

(VLOF). At 179 knots or 300 feet per second, the four seconds equates to an 

approximate distance of 1,200 feet between VR and VLOF. 

Figure 6-14. Liftoff Speed (VLOF). 

At VLOF, the flight guidance system will command a pitch that will allow continued 

acceleration to Climbout Speed (V2). This flight path assumes gear retraction is 

initiated three seconds after liftoff and completed 10.5 seconds later. From VLOF

to 50 feet AGL, the aircraft is accelerated to V2 (figure 6-14). 
KC-10 Aircrew Training System 

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6.4 SPEED FOR BEST ANGLE OF CLIMB 

Figure 6-15. Climbout Speed (V2).

Climbout speed (V2) is established at a height of 50 feet above the takeoff altitude and 

is maintained, with the flaps and slats in the takeoff configuration, until the Pressure 

Height for Acceleration is reached (figure 6-15). This speed satisfies the FAA 

requirement of 115% of the 1.0g stall speed. If Rotate Speed (VR) was increased to 

equal VR MIN, then V2 must be increased by the same increment. 

Figure 6-16. Pressure Height For Acceleration.

At the acceleration height, the aircraft is leveled off and the flaps and slats are retracted 

according to the recommended schedule. (Figure 6-16). 

2 ENGINE 

ACCELERATION 

STANDARD FLIGHT PATH 

(LOSS OF AN ENGINE)

MCT 

VSR

PRESSURE HEIGHT 

FOR ACCELERATION 

50 FT 

V2

VCEF

(ENGINE FAILURE) 

VR VLOF

VFR

80 KNOTS 

80 KNOTS 

PRESSURE HEIGHT 

VLOF V2 FOR ACCELERATION 

50’ 

ALL ENGINE 

ACCELERATION 

CFL 
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Introduction to KC-10 Takeoff Performance 

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W831-06 6-11 01 JUL 13 

6.5 PRESSURE HEIGHT FOR ACCELERATION

Figure 6-17. Climbout Flight Path.

The two-engine pressure height for acceleration is the height that level off, 

acceleration and cleanup should be accomplished. This is done to ensure the 

climbout flight path for obstacle clearance is achieved. The charted pressure 

height is a base geometric height of 1,500 feet above the takeoff altitude, based 

on standard day temperatures. This base height is adjusted up or down to 

account for non-standard conditions (figure 6-17). 

CLIMBOUT FLIGHT PATH 

PRESSURE HEIGHT 

FO ACCELERATION

OBSTACLE HEIGHT ABOVE LIFTOFF 

CLIMBOUT FLIGHT PATH 

7.0 

3.88 

6.0 

5.0 

3.88 

3.0 

3.5 

3.0 

3.5 

2.5 

2.5 
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W831-06 6-12 01 JUL 13 

 

 

Figure 6-18. Two Engine Pressure Height For Acceleration.

The minimum height for acceleration with an engine inoperative is based on two 

conditions: Pressure Height for Acceleration or 400 feet above the runway 

(AGL). Pressure Height for Acceleration is based on obstacle clearance height 

and accounted for with the computed climb gradient. (figure 6-18). 

CHARTED PRESSURE HEIGHT FOR ACCELERATION 

400’ AGL (Does Not Ensure Obstacle Clearance) 

or

2

1
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W831-06 6-13 01 JUL 13 

6.6 OBSTACLE HEIGHT AND DISTANCE COMPUTATIONS

Figure 6-19. Distant Terrain Clearance.

Remember, after operating at takeoff rated thrust for ten minutes or upon 

reaching 2000 feet pressure altitude above the airfield, whichever occurs first, the 

thrust is reduced to MCT. Clearing distant obstacles, such as high terrain, is 

predicated on leveling off at the pressure height for acceleration, retracting the 

flaps and slats, and climbing at slat retract speed until terrain clearance is 

achieved or the minimum height for enroute operations is reached. Now look at 

some procedures for defining obstacles. 

STANDARD FLIGHT PATH 

(LOSS OF AN ENGINE) MCT 

VSR VFR VCEF

(ENGINE FAILURE) V2

80 KNOTS VR VLOF

2 ENGINE 

ACCELERATION 

PRESSURE HEIGHT 

FOR ACCELERATION 

50 FT 

LEVEL OFF AND 

ACCELERATE 

AT CHARTED 

PRESSURE HEIGHT 

FOR ACCELERATION 

MCT AT VSR

DISTANT 

TERRAIN 

ALL ENGINE 

ACCELERATION 
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Figure 6-20. Obstacle Height & Distance.

You recall that the obstacle distance is measured from the Departure End of the 

Runway (DER). The height is listed as above mean sea level (MSL). 

Remember, field elevation on the TOLD card is the highest point on the airport’s 

usable runways. If the runway has no slope, then simply subtract the field 

elevation from the obstacle height to find the actual obstacle height AGL (figure 

6-20). 

846

-746

100'AGL

1

1 846'

OBSTACLES

SPOT ELEVATION

OBSTACLE

HIGHEST OBSTACLE

HIGHEST SPOT ELEVATION

GROUP OF OBSTACLES

DOUBTFUL ACCURACY
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Figure 6-21. Airfield Diagram.

Most Flight Information Publications in use today have Airfield Diagrams and Standard 

Instrument Departures included. The Airfield Diagrams have the Departure End of 

Runway Elevation or DER Elev (figure 6-21) listed and the SIDs have the controlling 

obstacles identified for the specific departure route. If the DER elevation is known, 

subtract this from the obstacle height to obtain the obstacle height AGL.

DER 

ELEV 
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OBSTACLE IS 100' ABOVE FIELD ELEVATION

FIELD RW

SLOPE 1.2%

1,300 MSL

ELEVATION

1,200'

LENGTH

12,200'

OBSTACLE IS 100' ABOVE FIELD ELEVATION

FIELD RW

SLOPE 1.2%

1,300 MSL

ELEVATION

1,200'

LENGTH

12,200'

Figure 6-22. DER Elevation Not Known.

If the departure end of the runway elevation is unknown and you are using field 

elevation to compute the obstacle height, you must correct the published 

obstacle height for downhill runway slope. Figure 6-22 shows an obstacle at 

1,300 MSL with a field elevation of 1,200 feet. If you subtract the field elevation 

from the obstacle height you would find the obstacle height to be 100 feet AGL. 

However, the runway shows a 1.2 percent downhill gradient. Now look at figure 

6-23. 

OBSTACLE HEIGHT (AGL) = OBST HT (MSL) - (FIELD ELEVATION - RUNWAY LENGTH X SLOPE) 100

Figure 6-23 Formula 

To determine obstacle height above ground level (AGL) with a downhill slope: 

a. Multiply the runway length by the runway slope. 12,200 x 1.2 = 14,640

b. Divide the result by 100. 14,640 / 100 = 146.4

c. Subtract the result from the field elevation. 1,200 - 146 = 1054

d. Now, subtract this number from the obstacle height (MSL). 1,300 - 1054 = 246

e. This is the corrected obstacle height (AGL). 246 feet (AGL)

Note: If you use the "percent" (%) function of your computer, skip the "divide by 

100" step. 
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W831-06 6-17 01 JUL 13 

Figure 6-24. Result.

Here you see the result of your calculation and the necessity for it (figure 6-24). 

The obstacle is only 100 feet above the field elevation. However, the downhill 

slope takes you below the obstacle. The obstacle is actually 246 feet above the 

departure end of the runway. The last 146 feet of that water tank would ruin your 

whole day!! 

OBSTACLE IS 100' ABOVE FIELD ELEVATION

FIELD RW

DOWNHILL SLOPE

1,300 MS

BUT

OBSTACLE IS 246' ABOVE DEPARTURE END OF RUNWAY

146' ADDITIONAL

ELEVATION

1,200'

LENGTH

12,200'

1,300 MSL
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Figure 6-25. Delta Obstacle Height Correction.

Even if the departure end of the runway elevation is known, any downhill slope 

must be applied to the obstacle height prior to entering the climb gradient 

chart. This has nothing to do with elevation, but rather the aircraft downhill 

trajectory. The momentum of an aircraft with the mass of the KC-10 is such that 

it will take the aircraft below the charted flight path. “A” in figure 6-25 shows the 

charted vs. actual flight path with no correction. “B” in figure 6-25 shows the flight 

path after the delta height correction. There is a chart for close-in obstacles, and 

a standard 24 feet for each one percent of runway slope for the rest. 

(NOT CORRECTED 
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Figure 6-26. Runway Reduction.

Because of the way KC-10 takeoff performance is calculated, with engine out 

liftoff at the end of the runway, there are times when close-in obstacles require a 

climb gradient in excess of 9.0%. Since 9.0% is the highest gradient available, 

the distance to the obstacle must be increased by decreasing the runway 

available by a like amount (figure 6-26). Both uphill and downhill slope is applied 

to the decreased runway increment and the obstacle height adjusted accordingly. 

This procedure will be covered in detail in another workbook. 
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W831-06 6-20 01 JUL 13 

6.7 SPECIAL DEPARTURE PROCEDURE 

 

 The Air Force Flight Standards Agency (AFFSA) has contracted with Jeppesen 

 to provide safe engine out departure procedures for bases used by the KC-10 to 

 provide the maximum takeoff weight possible and miss any obstacles should an 

 engine fail during takeoff. Special Departure Procedure information is found at 

 “http://www.jeppesen.com” on the Internet. 

Jeppesen analyzes terrain and obstacle data against aircraft specific 

performance data to determine the best engine out departure and takeoff weight 

for each runway at a given location. Username and passwords change 

periodically; please contact your instructor or squadron for current information. 

Once logged into the website, click on OpsData, which will take you to the 

OpsData Search menu. Now select KC-10A/A/CF6-50C2 under Aircraft and type 

in Airport Keyword (ICAO identifier). The next screen will allow you to view 

specific airport data. You can also select the View Entire List to allow selection of 

any airfield within the data base. 

A User Guide can be viewed or downloaded and is also available below the Ops 

Data menu. Only bases that have approved procedures are listed on the 

Jeppesen website. This website should be checked during mission planning. If 

an approved procedure is available, it must be briefed and used if an engine 

failure occurs on takeoff. TOLD and/or SDP departure plate information can be 

found on the website, and has been approved by the Air Force for TOLD 

computations. 

Complete the lesson exercise prior to continuing. 
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6.7 LESSON EXERCISE

 1. The concept that the distance to continue the takeoff on two engines or 

stop in the same distance is called the ________________________ 

concept. 

 2. The "Maximum Takeoff Gross Weight at Optimum Flap Setting" charts 

attempt to balance the runway required for takeoff by varying the 

____________ setting based on runway available and required climb 

gradient. 

 3. A static takeoff may be accomplished if the wind direction is less than 

__________ degrees off the runway heading or the crosswind component 

is ________ knots or less. 

 4. At V1 the Pilot has _________ seconds of reaction time from an engine 

failure and make the abort decision. 

 5. If the decision is made to abort the takeoff, ____________ seconds are 

allocated to bring the throttles to idle and commence the abort process. 

 6. The engine fail system is armed when the N1 is advanced past 

__________ and is activated when an ___________ difference or greater 

is detected. 

 7. When performing a reduced power takeoff, takeoff rated thrust may not be 

applied until an airspeed of 135 knots. This is because Ground Minimum 

Control Speed has been computed using ________________ 

Temperature. 

 8. Rotate Speed may never be lower than VMCG ___________/________, 

which is VR MIN. 

 9. The KC-10 is rotated from a three-point attitude to an angle of attack that 

will allow enough lift to become airborne at VLOF. This will take 

approximately _______ seconds. 

10. The flight path assumes that gear retraction is initiated _______ seconds 

after liftoff and completed __________ seconds later. 

11. From Liftoff to a height of________ feet, the aircraft is accelerated to 

__________ speed (V2). 

12. If Rotate Speed was increased to equal VR MIN, then _____________ must 

be increased by the same increment. 
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13. Engine out climbout speed is maintained using takeoff power for ten 

minutes or ____________ feet pressure altitude above the airfield, 

whichever occurs first. Power is then reduced to __________. 

14. The two engine minimum pressure height for acceleration is __________ 

feet AGL; the height of the ______________________________; or 

charted _________ __________ for _________________. 

15. The only means to guarantee distant obstacle clearance is to level off at 

_______________________________________, cleanup, and maintain 

_____________________ speed until the obstacle is cleared or the 

minimum altitude for enroute operations is reached. 

16. Obstacle distance is the horizontal distance from the ______________ 

end of the runway to the obstacle. 

17. Obstacle height is depicted as height above __________________. 

18. Field Elevation is the highest point on the runway surface. It may be used 

to compute obstacle height if the runway has no ___________. 

19. If the elevation at the departure end of the runway is not known, and a 

downhill slope exists, the actual obstacle height can be calculated using 

the runway ________ times the runway slope in percent, and that height 

added to the obstacle height as computed from the field elevation. 

20. In all cases, a downhill slope will require a obstacle height correction to 

account for the _________________________ of the aircraft. 

21. In some cases, when the climb gradient required exceeds 9.0%, the 

distance to the obstacle must be increased. This is done by decreasing 

the _____________________ until a gradient of 9.0% or less is attained. 
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W831-06 6-23 01 JUL 13 

6.8 LESSON EXERCISE ANSWER KEY

 1. balanced field 

 2. flap 

 3. 45/23 

 4. 3 

 5. 1.1 

 6. 85%/11% 

 7. assumed 

 8. wet/icy 

 9. 4 

10. 3/10.5 

11. 50/climbout 

12. V2

13. 2,000/MCT 

14. 400/controlling obstacle/pressure height/acceleration 

15. pressure height for acceleration/slat retract 

16. departure 

17. mean sea level 

18. downhill slope 

19. length 

20. downhill trajectory 

21. runway available 
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W831-06 6-24 01 JUL 13 

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