Section 1, Chapter 3 - Separation Standards Flashcards
What are the requirements for providing standard separation in different classes of airspace?
Standard Separation Requirements:
Provided Between:
- All flights in Class A airspace.
- IFR flights in Class C, D, and E airspace.
- IFR flights and VFR flights in Class C airspace.
- IFR flights and Special VFR flights.
- Special VFR flights, except where a reduction is authorized by the CAA.
Class G Airspace:
- Separation between aircraft is ultimately the pilot’s responsibility.
- Controllers providing a Deconfliction Service or a Procedural Service will offer information and advice to achieve defined deconfliction minima.
When should separation standards be increased?
Separation standards, which are minima, should be increased when:
- Requested by the pilot.
- A controller considers it necessary.
- Directed by the CAA.
When can standard separation minima be reduced in the vicinity of aerodromes?
Standard separation minima in the vicinity of aerodromes can be reduced if:
- Adequate separation can be provided by the aerodrome controller when each aircraft is continuously visible to this controller.
- Each aircraft is continuously visible to the pilots of the other aircraft concerned and the pilots report that they can maintain their own separation.
- When one aircraft is following another, the pilot of the succeeding aircraft reports the other aircraft is in sight and can maintain their own separation.
When can standard separation be reduced during a Search and Rescue (SAR) escort?
Standard separation may be reduced when a SAR aircraft is escorting an aircraft in an emergency. There is no minimum separation laid down in UK FIRs, and separation may be reduced to what can be maintained visually or with airborne surveillance.
What actions should a controller take in a situation where two or more aircraft are separated by less than the prescribed minima?
If two or more aircraft are separated by less than the prescribed minima, the controller should:
- Use every means at their disposal to obtain the required minimum separation with the least possible delay.
- When practicable, pass traffic information if an ATS surveillance service is being provided; otherwise, pass essential traffic information.
What is essential traffic information and what should it include?
Essential traffic information is provided when traffic is separated by less than the specified standard separation, usually when ATS surveillance systems are not available.
It should include:
- Direction of flight of conflicting aircraft.
- Type of conflicting aircraft.
- Cruising level of conflicting aircraft and ETA for the reporting point, or for aircraft passing through the level of another with less than normal separation; the ETA for the reporting point nearest to where the aircraft will cross levels.
- Any alternative clearance.
What are the vertical separation minima between aircraft?
Vertical Separation Minima:
Between aircraft flying subsonic:
* Up to FL290: 1,000 ft
* Above FL290: 2,000 ft, except between FL290 and FL410 inclusive, 1,000 ft may be applied between RVSM approved aircraft operating in designated airspace.
Between aircraft flying supersonic and between supersonic and subsonic aircraft:
* Up to FL450: 2,000 ft
* Above FL450: 4,000 ft
Additional Considerations:
* If a pilot advises that their aircraft is no longer capable of RVSM operations, the first ATSU aware of the failure must coordinate with subsequent ATSUs.
* The Mode C of some military aircraft is accurate only to the nearest 400 ft during supersonic flight; thus, 4,000 ft separation may be applied at all levels.
* Controllers should assess the vertical distance by observing Mode C responses or obtaining level reports from pilots.
How may aircraft be instructed to change levels?
Aircraft may be instructed to change levels at a specified time, place, or rate.
Under what conditions can an aircraft be instructed to climb or descend to a level previously occupied by another aircraft?
An aircraft may be instructed to climb or descend to a level previously occupied by another aircraft provided that:
- Vertical separation already exists.
- The vacating aircraft is proceeding to a level that will maintain vertical separation.
- Either:
1. The controller observes that the vacating aircraft has left the level, or
2. The pilot has reported vacating the level.
What should be done if severe turbulence is known to exist when instructing an aircraft to change levels?
If severe turbulence is known to exist, instructions shall be delayed until the vacating aircraft is known to be at, or through, another level separated by the required minimum.
What must controllers consider when instructing an aircraft to climb or descend to a previously occupied level?
Controllers must exercise caution and consider that aircraft may climb or descend at markedly different rates. If necessary, additional measures such as specifying a maximum or minimum climb or descent rate for each aircraft should be applied to ensure the required separation is maintained.
This is particularly relevant when the aircraft are established in the same holding pattern.
Under what conditions may controllers authorize an aircraft to climb or descend in VMC?
Controllers may authorize an aircraft to climb or descend in VMC provided:
- The manoeuvre is restricted to Class D, E, F, and G airspace at or below FL100.
- It is during the hours of daylight.
- The aircraft is flying in visual meteorological conditions.
- The pilot of the aircraft climbing or descending agrees to maintain their own separation from other aircraft and the manoeuvre is agreed by the pilot of the other aircraft.
- Essential traffic information is given.
What must be considered regarding TCAS RA when authorizing VMC climb and descent in Class D airspace?
The application of VMC climb and descent could trigger a TCAS RA. Therefore, in Class D airspace when surveillance services are being provided, VMC climb and descent shall only be used where authorized and in accordance with any conditions specified in MATS Part 2.
What are the three types of horizontal separation?
The three types of horizontal separation are:
- Lateral separation
- Longitudinal separation
- Separation based on ATS surveillance system information
What does “level change” mean in the context of horizontal separation?
“Level change” refers to the portion of the climb and descent during which the vertical separation in relation to the level of another aircraft is less than the minima.
When are wake turbulence separation minima applied to aircraft on final approach according to SERA.8012?
Wake turbulence separation minima are applied to aircraft on final approach when:
- An aircraft is operating directly behind another aircraft at the same altitude or less than 1,000 ft below.
- An aircraft is crossing behind another aircraft at the same altitude or less than 1,000 ft below.
- Both aircraft are using the same runway or parallel runways separated by less than 760 m.
When are wake turbulence separation minima applied to aircraft on departure according to SERA.8012?
Wake turbulence separation minima on departure are applied when aircraft are using:
- The same runway.
- Parallel runways separated by less than 760 m.
- Crossing runways if the projected flight path of the second aircraft will cross the projected flight path of the first aircraft at the same altitude or less than 1,000 ft below.
- Parallel runways separated by 760 m or more, if the projected flight path of the second aircraft will cross the projected flight path of the first aircraft at the same altitude or less than 1,000 ft below.
Take-off clearance may be issued with an allowance for the anticipated take-off run on the runway, but the airborne time interval must reflect at least the required time separation.
