Document ID: chunk:federal_register_of_legislation:F2023C00696:body:0:p58
Version: federal_register_of_legislation:F2023C00696
Segment Type: other
Provision Reference: 
Character Range: 222471–225373

in the ATC's estimation of future positions of the aircraft in conflict;

(d)         a control tolerance of ±2 MIN for control factors such as communications delays, clock errors and human factors;

(e)         each of these tolerances is combined by the root sum square (RSS) method; and

(f)            a buffer of 3 MIN added arithmetically.

10.9.3.2         The minimum time separation between two aircraft which are neither laterally nor vertically separated, therefore, equals:
 MIN,

Where:
d = magnitude of the CEP (NM) and
G/S  = minimum groundspeed (KT).

10.9.3.3         10 MIN separation between aircraft flying the same or reciprocal tracks may apply within controlled airspace provided that:

(a)         for aircraft equipped with single INS/IRS the average groundspeed on a route section is not less than:
(i)            240 KT in CTA/TCTA/OCA and the update interval does not exceed 3 hours; or

(ii)          330 KT in OCA and the update interval does not exceed 5 hours; and

(b)         for aircraft equipped with two or more INS/IRS, the average groundspeed on a route section is not less than 240 KT and the update interval does not exceed 5 hours.

10.9.3.4         15 MIN separation between aircraft flying the same or reciprocal tracks may apply within controlled airspace provided that:

(a)         for aircraft equipped with single INS/IRS, the update interval does not exceed 5 hours; and

(b)         for aircraft equipped with two or more INS/IRS, the average groundspeed on a route section is not less than 240 KT and the update interval does not exceed 12 hours.

10.9.3.5         20 MIN separation between aircraft flying the same or reciprocal tracks may apply within controlled airspace provided that:

(a)         for aircraft equipped with single INS/IRS, the update interval does not exceed 5 hours; and

(b)         for aircraft equipped with two or more INS/IRS, the update interval does not exceed 12 hours.

10.9.4              Distance Standards

10.9.4.1         The longitudinal separation minima based on distance are derived using the following assumptions and methods:

(a)         the along-track navigational tolerance of an aircraft is taken as the same as for the time standards;

(b)         when "NO CLOSING SPEED" is stipulated as a condition, minor variations of 4% of TAS of each aircraft, taken as 450 KT for the initial climb and 600 KT maximum thereafter, are allowed;

(c)          when separation is to be checked at  "FREQUENT INTERVALS" to ensure that the minimum will not be infringed, the maximum interval between checks is taken as 15 MIN;

(d)         each of these tolerances is combined by the RSS method;

(e)         except in the case of the R2 (definite passing) standard, a buffer of 10 NM is added arithmetically. The distance standard, therefore, equals:

where:
 d = magnitude of the CEP (NM)
 dc = 'closure' distance of