18 Aerodrome Distances Flashcards
The TODR is the greater of:
- 1.15 x the all-engine TOD, and
- The gross one-engine-out TOD.
V_1wet
A wet runway has a reduced braking, coeffcient of friction which means less deceleration during a rejected take-off.
If the decicion at V1wet is to continue, the AC need only be 15ft at the end of the TODA.
The requirement for TOD on a wet runway?
- TOD_dry: The take-off distance on a dry runway described on the previous page, i.e., TOD_N dry and 1.15 × TOD_N dry.
- TOD_wet: The horizontal distance along the take-off path from the start of the take-off to the point at which the aeroplane is 15 ft above the take-off surface for a wet runway, assuming the critical engine fails at a V_EF corresponding to V_MU wet, and ensuring that V_2 is achieved before the aeroplane is 35 ft above the take-off surface.
The TOR on a dry runway?
The take-off run on a dry runway is the greater of:
- TOR_N dry: The horizontal distance along the take-off path from the start of the take-off to the point equidistant between V_LOF and where the airplane is 35 ft above the take-off surface with an engine having failed at V_EF.
- 1.15 × TOR_N dry: 115% of the horizontal distance along the take-off path from the start of the take-off to the point equidistant between V_LOF and where the airplane is 35 ft above the take-off surface with all engines operating.
The TOR on a wet runway?
The take-off run on a wet runway is the greater of:
- TOR_N wet: The horizontal distance along the take-off path from the start of the take-off to the point at which the airplane is 15 ft above the take-off surface for a wet runway, consistent with achieving V2 before reaching 35 ft, with the critical engine failing at V_EF.
- 1.15 × TOR_N wet: 115% of the horizontal distance along the take-off path with all engines operating from the start of the take-off to a point equidistant between the point at which V_LOF is reached and the point at which the airplane is 35 ft above the take-off surface.
ASD on a dry runway?
- The ASD on a dry runway is the greater of the all-engine ASD and critical-engine-out ASD (ASD_N-1).
- As per CS-25.109(f), we take no account of reverse thrust on a dry runway.
ASD_N-1
ASD_N-1 is the sum of the distances necessary to:
- Accelerate the aeroplane from a standing start with all engines operating to V_EF for take-off from a dry runway.
- Allow the aeroplane to accelerate from V_EF to the highest speed reached during the RTO, assuming the critical engine fails at V_EF and the PF takes the first action to reject the take-off at V_1 on a dry runway.
- Come to a full stop (no reverse thrust) on a dry runway from the highest speed reached, plus a distance equivalent to two seconds at the V_1 speed
ASD_N
ASD_N is the sum of the distances necessary to:
- Accelerate the aeroplane from a standing start with all engines operating to the highest speed reached during the rejected take-off, assuming the PF takes the first action to reject the take-off at V_1 for take-off from a dry runway.
- Come to a full stop on a dry runway plus a distance equivalent to two seconds at the V_1 speed.
The ASD on a wet runway?
- The ASD on a dry runway.
- ASD_N and ASD_N-1 as above for a dry runway except that the runway is wet and the corresponding wet runway values for V_EF and V_1 are used. The effects of reverse thrust may be included.
The advantage of a balanced field?
Can be used to find the runway limiting mass.
Balanced field?
ASDA = TODA
Balanced take off?
Aircrafts OEI TOD, (TODn-1) equals the AC accelerate stop distance.
How does TODn-1 vary with V1?
How does ASD vary with V1?
Where is balanced field in terms of TODn-1 and ASD?
