2.
For Frankfurt Airport, a calculation was carried out for all landing directions, and the results are presented in the chart enclosed.
The runway occupancy time is defined as the elapsed time a landing aircraft is on a runway, from crossing of threshold until vacating the runway by reaching a distance of 30 m from the runway centre line.
The runway occupancy time is composed of different phases;
-Time from crossing the threshold to touchdown;
-Time from touchdown to the runway turn-off point (braking time), including, if necessary, time for transition or a transition route after touchdown without run-up;
-Time from the turn-off point to vacating the runway until reaching a distance of 30 m from the runway centre line.
3. In order to determine the runway occupancy time, the following assumptions were taken as a basis.
-In order to calculate the turn-off time from the runway to vacating the runway, an approach speed of 120 kt is assumed for a B 727, for an A 300 an approach speed of 130 kt, and for a B 747 an approach speed of 140 kt. These assumptions are important for the determination of the roll-out distance.
-The touchdown point is the location of the glide path transmitter;
-After touchdown and roll-out, the aircraft takes the nearest (rapid) exit taxiway.
4. The results have shown that under the above-mentioned circumstances and assumptions runway occupancy times of 50 seconds and less can be achieved.
The table also includes the following details:
-The delay values b which were arithmetically calculated for the braking distance after touchdown; and
-The distance of the following aircraft from the threshold in NM or km when the preceding aircraft has vacated the runway by reaching a distance of 30 m.
Runway Occupancy Time Airport Frankfurt
Runway Heading Taxiway Approach speed Runway Occupancy Time Decel-aration factor (b) Distance of following aircraft to touchdown (Initial separation 2,5 NM)
KT sec m/sec.2 NM km
25 R Gto Ato Ato Ato 120 120 130 140 39,2 44,3 1) 47,5 1) 49,8 - 2,3 - 1,8 - 2,3 - 1,8 1,19 1,02 0,78 0,56 2,210 1,895 1,450 1,045
25 L G Hto Hto Hto 120 120 130 140 41,0 48,9 1) 50,0 1) 49,0 1) - 2,4 - 1,5 - 2,4 - 2,5 1,13 0,87 0,69 0,59 2,100 1,610 1,290 1,100
07 R Cto Cto Cto 120 130 140 44,8 1) 48,1 1) 50,0 - 1,8 - 2,3 - 1,7 1,00 0,76 0,56 1,850 1,410 1,045
07 L Mto Mto Mto 120 130 140 47,1 1) 50,0 1) 49,2 1) - 1,6 - 2,1 - 2,1 0,93 0,69 0,59 1,720 1,290 1,085
Hto (07) planned 120 42,7 - 1,9 1,08 2,000
1) transition zone calculated without braking
