(2) ATM - Vertical Separation

Question 1

How is vertical separation obtained? (1)

Answer 1

By requiring aircraft using prescribed altimeter setting procedures to operate at different levels expressed in terms of Flight Levels or altitudes

Question 2

What is the vertical separation minimum (VSM) requirement? (4)

Answer 2

1000ft <F290
2000ft at/>F290

Within designated airspace:

1000ft <F410
2000ft at/>F410

Question 3

What are the VFR cruising levels? (4)

Answer 3

• Above 3000ft
• +500ft
• levels up to F285
  (UK does not implement this)
• VFR above F290 is not approved

Question 4

What are the rules of assigning cruising levels? (9)

Answer 4

• Normally one level assigned per aircraft
• It is the responsibility of the accepting ATCU to issue clearance for further climb, as appropriate
• Aircraft authorised to employ cruise climb techniques shall be cleared to operate between two levels or above a level
• If necessary to change a cruising level of an aircraft on an ATS route, do so inside CAS (if possible)
• When an aircraft has been cleared into a CTA at a cruising level which is below the minimum cruising level for a subsequent portion of the route, the ATCU responsible for the area should issue a revised clearance to the aircraft even though the pilot has not requested the necessary cruising level change
• An aircraft may be cleared to change cruising level at a specified time, place or rate
• Cruising levels of aircraft flying to the same destination shall be assigned in a manner that will be correct for an approach sequence at destination
• An aircraft at a cruising level shall normally have priority over other aircraft requesting that cruising level
• When two or more aircraft are at the same cruising level, the preceding aircraft shall normally have priority

Question 5

How may an aircraft may be cleared to change cruising level at? (3)

Answer 5

• Specified time
• Specified place
• Specified rate

Question 6

What happens when RVSM fails? (1)

Answer 6

Conventional 2000ft separation (CVSM) above
FL290 is used

Question 7

RVSM vs CVSM table diagram

Answer 7

Question 8

What are the effects of RVSM? (6)

Answer 8

• Pilots must ensure they are RVSM compliant to fly in RVSM airspace, otherwise flight plan to fly below it
• If in RVSM and equipment fails, inform ATC asap who will issue alternate clearance
• During operations in or vertical transit through RVSM airspace for non RVSM aircraft, pilots shall report non-approved status:

1. At initial call
2. In all requests for level changes
3. in all readbacks of level clearances

Question 9

When may an aircraft may be cleared to a level previously occupied by another aircraft? (1)

Answer 9

When the previous aircraft has reported vacated of that level

Question 10

What are the exceptions of an aircraft being able to be cleared to a level previously occupied by another aircraft reporting vacated? (3)

Answer 10

1. Severe turbulence is known to exist
2. The higher aircraft is effecting a cruise climb
3. The difference in aircraft performance is such that less than the applicable separation may result

Question 11

When may pilots be able to be cleared to maintain a specified vertical separation between their aircraft during ascent or descent? (2)

Answer 11

• When in direct communication with each other
• With their joint agreement

e.g. ‘CLIMB (or DESCEND) AT (number) FEET PER MINUTE OR GREATER / OR LESS)’