Airspace

Question 1

What are the main airspace categories within the FIRs?

Answer 1

• Controlled

- Uncontrolled

Question 2

What does the airspace classification within a FIR determine?

Answer 2

• The rules which apply,
• The minimum services which are to be provided, and
• Generally termed controlled and uncontrolled airspace

Question 3

How many and what are the airspace classes in the UK?

Answer 3

There are presently 5 classes of airspace.

• A, C, D and E are classes of controlled airspace
• Class G is outside controlled airspace

Question 4

What are the requirements of controlled airspace?

Answer 4

• Aircraft which fly in controlled airspace must be equipped to a certain standard
• Pilots must hold the necessary qualifications
• Pilots must obtain a clearance from ATC to enter such airspace and,
• Pilots must follow ATC instructions implicitly, except in an emergency situation

Question 5

Class A airspace

Answer 5

• Only Instrument Flight Rules (IFR) flights are permitted.
• The most strictly regulated airspace; pilots must comply with ATC instructions at all times.
• Aircraft are separated from all other traffic

Question 6

Class C airspace

Answer 6

• Extends from FL 195 to FL 660.
• Both IFR and Visual Flight Rules (VFR) traffic operates
• Requires a clearance to enter the airspace and,
• Compliance with ATC instructions are mandatory

Question 7

Class D airspace

Answer 7

• Both IFR and VFR
• ATC clearance is needed
• Compliance with ATC instructions are mandatory
• Control areas around aerodromes are Class D
• A speed limit of 250kts below FL100 applies

Question 8

Class E airspace

Answer 8

• Both IFR and VFR
• IFR traffic requires ATC clearance and compliance with ATC instructions is mandatory
• VFR traffic does not require a clearance to enter class E airspace

Question 9

What are the types of controlled airspace?

Answer 9

• Aerodrome Traffic Zones (ATZ) - immediate vicinity of aerodrome
• Aerodrome Control Zones (CTR)
• Control Areas (CTA) - situated above ATZ, protection of larger area to a specified upper limit
• Terminal Control Areas (TMA)
• Airways
• Upper Air Routes (UARs) or Upper Airspace

Question 10

TMA

Answer 10

Normally established at the junction of airways in the vicinity of one or more major aerodromes.
LTMA (or LTCA) deals with traffic arriving and departing from:
- London Heathrow
- Gatwick,
- Luton,
- Stansted
- London City
- Northolt
- Biggin Hill
- Southend
- Farnborough
and other minor airfields in the London area

Question 11

What is Airway?

Answer 11

Airways are corridors connecting the TMAs and link up with airways in other countries too.

• Normally 10 miles wide
• Have bases between 5,000 feet and 7,000 feet
• Extend upward to a height of 24,500 feet

Question 12

What are Upper Air Routes (UARs) or Upper Airspace?

Answer 12

Sit above airways.
Vertical limits are usually FL 250-FL 460.
Both, civil and military aircraft above FL 245 are subject to full and mandatory ATC services

Question 13

Class G airspace

Answer 13

Uncontrolled airspace. Aircraft may fly when and where they like, subject to a set of simple rules.
No legal requirement to notify ATC of aircraft presence and intentions.
Pilots’s responsibility for their own safety and avoidance of other aircraft

Question 14

What services are available outside controlled airspace?

Answer 14

• Deconfliction Service
• Traffic Service
• Basic Service
  Two other types of service are:
• Alerting Service - is provided to notify appropriate organisations regarding aircraft in need of search and rescue aid and assist such organisations
• Procedural Service - is non radar-based service in which deconfliction advice is provided against other aircraft receiving a Procedural Service from the same controller.

Question 15

How are aircraft separated?

Answer 15

In controlled airspace separation is achieved by allocating aircraft different heights or by issuing headings (vectors) so that aircraft can be at the same height, but a minimum horizontal distance apart.

Question 16

What is the separation in LTMA (LTCA)?

Answer 16

In London Terminal Control Area aircraft operating under radar control must be separated 3NM from other aircraft at the same height.
If they are less than 3NM apart they must be separated by a minimum of 1,000ft.

Question 17

What is the separation outside of LTMA (LTCA)?

Answer 17

5NM if they are at the same level of 1,000ft vertically up to FL290.
Above this, 1,000ft vertical separation may continue to be provided up to FL410, subject to aircraft being suitably equipped to comply with Reduced Vertical Separation Minima (RVSM) rules, otherwise 2,000ft should be applied.