TOLD Definitions

Question 1

Takeoff Speed (TOS)

Answer 1

Speed at which main gear lifts off runway

Question 2

Takeoff Distance (TOD)

Answer 2

Distance from brake release to main gear liftoff

Question 3

SETOS (Single-Engine Takeoff Speed)

Answer 3

Speed at which the aircraft is able to climb, once clear of ground effect, at a minimum of 100 fpm with gear down, flaps 60%

Question 4

Critical engine failure speed (CEFS)

Answer 4

Speed at which aircraft accelerates with both engines experiences an engine failure and permits either acceleration to SETOS and T/O (approximately 700’ from start of rotation at SETOS) or decelerate to a stop in the same distance

Question 5

Critical field length (CFL)

Answer 5

Total runway length required to accelerate with both engines operational to CEFS, experience an engine failure, and accelerate to SETOS and T/O (approximately 700’ from start of rotation at SETOS) or decelerate to a stop in the same distance.

Question 6

Normal Acceleration Check Speed (NACS)

Answer 6

Speed an average T-38 should reach at a specified check distance

Question 7

Minimum Acceleration Check Speed (MACS)

Answer 7

Minimum acceptable speed at check distance with which T/O should be continued

Question 8

Refusal Speed

Answer 8

The max speed to which the aircraft is able to accelerate with both engines operating in MAX and either abort with BEO (both engines operating) or abort with EF (engine failure)

Question 9

Decision speed

Answer 9

Minimum speed at which the aircraft is able to experience instantaneous engine failure and still accelerate to SETOS and T/O (approximately 700’ from start of rotation at SETOS) in the remaining runway

Question 10

Landing distance

Answer 10

Ground roll distance after touchdown

Question 11

TORA (takeoff run available)

Answer 11

Length of runway available and suitable for T/O ground run

Question 12

TODA (takeoff distance available)

Answer 12

Length of runway available and suitable for T/O ground run plus clearway length

Question 13

ASDA (accelerate-stop distance available)

Answer 13

Runway plus stopway length available and suitable for acceleration and deceleration of an aborting aircraft

Question 14

LDA (landing distance available)

Answer 14

Runway available and suitable for ground run of aircraft landing

Question 15

Rotation speed

Answer 15

The speed at which aft stick is initiated

Question 16

50’ Obstacle Speed

Answer 16

A 7.5 degree pitch attitude is held through an altitude of 50’

Question 17

What are the assumptions about CFL?

Answer 17

“SA”

S-SETOS is what it’s valid up to
A-Assumes no aerobraking

Question 18

What are the assumptions about RS?

Answer 18

3 WANA DAB?
3-3 sec delay to recognize and react and pull throttles to Idle
W-wheel braking not used with aerobraking
A-Accel continues in MAX on both engines Idle (BEO) or one engine Idle, other windmilling (EF)
N-Nose settles to rwy at 120 knots
A-Attitude is 7.5 deg until 120 knots if abort with nose in TO attitude
D-desired braking in 2 sec if jet is in 3 pt attitude and a/s<130 and brakes gradually applied
A-Assumes no aerobrake
B-braking is cautious 100-130, optimum below 100

Question 19

What are the assumptions about SETOS?

Answer 19

RAM D Roc
Rotation initiated at SETOS for SE takeoff
Accelerate in 3 pt attitude, rotate NET SETOS
Minimum SETOS is 2-engine TOS
Delaying rotation improves performance (consider rwy length and tire limits)
Roc: (best rate of climb) 200 knots, gr down, 60% flaps
220 knots, gr down, flaps up

Question 20

What are the assumptions about DS?

Answer 20

3ARA
3 sec delay to react
Acceleration continues in       
  MAX on one engine, other windmilling
Rotation speed reached, jet begins 
   rotation to t/o attitude 
Attitude is 3 pt and aircraft accel to   
   SETOS with neutral stick at end of 3 
   sec reaction time

Question 21

What are the assumptions about MACS?

Answer 21

AC
Allows variation in throttle setting, engine trim, pilot technique
Compute by subtracting 3 knots from NACS per 1000’ rwy length excess of CFL

Question 22

What are the assumptions about NACS?

Answer 22

NC
Normal acceleration
Check distance speed must be less than go/no go speed; if not, recompute check distance