London City home
General Procedures
Approved aircraft
Files and links

Essex RAM home

 Come and
ride the glide!

Effective 10th February 2004

Click here to download file

1: Introduction

These notes have been written for Special VFR in the London/London City Control Zones but the general principles are applicable throughout Vatsim-UK.

A Special VFR flight is a flight made in a control zone under circumstances which would normally require the flight to be made under the Instrument Flight Rules (IFR) but is made under special conditions and with the permission of ATC instead of under full IFR.

Separate regulations will be published for helicopters.

2: Operating on a Special VFR clearance

SVFR clearance is required for a pilot unable to comply with IFR in order to fly

  • at any time in a Class A Control Zone
  • in any other control zone
    • at night
    • when visbility is too poor for VFR (In Class D below 3000ft and 140 knots, the minimum visibility for VFR is 5km)

When operating on a Special VFR clearance the pilot must

  • obtain an ATC clearance and comply with ATC instructions
  • fly within the limitations of the pilot's licence
  • remain clear of cloud, in sight of the surface and clear of obstructions
  • comply with the low-flying regulations

a) fly at sufficient height to be able to land clear of the area and without danger to people or property if an engine fails
b) NOT fly closer than 500 ft to any person, vessel, vehicle or structure, unless landing or taking off

  • avoid aerodrome traffic zones unless prior permission has been obtained from ATC

SVFR clearance exempts the pilot from the 1500ft rule.

SVFR clearance will not normally be granted for aircraft with an All Up Weight greater than 5700kg and that are capable of flight under IFR

SVFR clearance will only be granted when traffic conditions will enable the flight to take place without hindrance to normal IFR flights.

Weather minima

Vatsim pilots are assumed to hold an IMC rating. This permits flight on a SVFR clearance with a minimum flight visibility of 3km and in sight of the surface. The minimum visibility for take off or landing is 1800m.

ATC will not issue a SVFR clearance to any fixed-wing aircraft for departure from an aerodrome within a control zone when the visibility is 1800m or less, or the cloud ceiling is less than 600ft.

The following additional criteria apply to SVFR clearances into/out of Heathrow
i) inbound fixed wing:  visibility at least 10km, cloud base not less than 1200ft
ii) helicopters:             visibility at least 2km


Standard separation of 3nm or 1000ft is applied between IFR and Special VFR flights, and between all Special VFR flights. Traffic information will be passed on known VFR aircraft.

No separation can be provided between Special VFR flights flying in the access lanes and local flying areas for Denham (EGLD), White Waltham (EGLM) and Fairoaks (EGTF) aerodromes.

In order to maintain separation ATC may impose a height limitation which will require the pilot to fly at or not above a specific level. A specific geographical route may be given, and it may be necessary to issue a radar heading to maintain lateral separation.

The pilot must inform ATC if ATC instructions would prevent him from complying with the flight conditions in para 2.  Alternative instructions will then be given

Requests for clearance
A full flightplan is not required, but ATC must be given brief details of the call sign, aircraft type and pilot's intentions. A request for Special VFR clearance to enter or transit a Control Zone may be made while airborne; it must specify the ETA for the selected entry point, and be made 5-10 minutes beforehand.
Radio failure

In the case of radio failure

  • squawk 7600 and Mode C
  • if not yet in the CTR, remain clear even if Special VFR clearance has been given
  • if in the CTR and inbound to an aerodrome in the CTR, proceed in accordance with Special VFR clearance to the aerodrome and land as soon as possible
  • if transiting the CTR, continue flight not above the cleared altitude to leave the CTR by the most direct route, taking into account weather limitations, obstacle clearance and areas of known dense traffic.
3: ATC procedures

On Vatsim- UK ATC services to Special VFR traffic in the London/London City Control Zones are provided by Thames Radar on 132.70. In the absence of Thames Radar, the service will be provided by EGLL_N_APP if available.

The London/London City squawk codes for Special VFR are 7030-7047. Traffic survey aircraft will operate on permanently assigned squawk codes: Capital Radio (CAP) on 7100, and London Executive Aviation (LNX 500) on 7200.


Standard radar separation of 3nm or 1000ft must be provided between all traffic under the control of the Special VFR controller. The SVFR controller is also responsible for providing separation between that traffic and any other controlled traffic i.e. IFR traffic in the London/London City CTR and airways, and London Heliport traffic.  IFR traffic takes precedence over SVFR except in an emergency.

Traffic information will be passed to VFR flights on IFR and SVFR flights and vice versa.

Separation will be provided by altitude restriction, geographical routing, or vectors. Wherever possible specific headings and altitudes should be avoided. Altitudes “not above xxxx ft” and geographical routes are preferred.

At London Heathrow, arriving aircraft on the ILS, ,and departing aircraft following the SIDS will cross 7dme at 2000ft. To avoid conflict SVFR flights should remain at least 3nm north or south of the EGLL extended runway centre line. Zone transits will be granted outside 7dme, and will be via the official routes specified in para 3.6.

Within the London City Zone traffic which has been instructed to remain north of the River Thames and traffic which has been instructed to remain south of it can be considered to be adequately separated as long as all pilots are kept informed of relevant traffic.

Altitude restriction
Where possible altitude restrictions should be expressed as “not above xxxxft”. This allows aircraft to change altitude below the restriction to remain in VMC without needing to repeatedly inform ATC. The altitudes are allocated to ensure aircraft remain below TMA airspace, and to maintain separation from traffic inbound to Heathrow on the ILS.

Minimum altitudes (see chart)
A minimum altitude of 1500ft will normally be applied to all SVFR aircraft

1) within the sector 020º to 140º from Heathrow in the Heathrow Control Zone.

2) In the London City Control Zone: all aircraft operating in the London City Zone west of a line North/South through the Isle of Dogs, except for helicopters following H4.

In order to provide vertical separation from IFR traffic approaching or departing EGLL or EGLC, SVFR aircraft transiting the zone may need to be restricted to a maximum altitude of 1500ft (see para 3.6). To conform to both maximum and minimum altitudes it may be necessary to issue the instruction to fly “at 1500ft”.

Outside the Heathrow 020º to 140º sector, aircraft should only be instructed to fly lower than 1500ft if it is necessary to maintain separation. Separate regulations apply to helicopters.

Maximum altitudes (see chart)
The maximum available altitude for SVFR traffic is 2400ft. To provide separation from Heathrow inbound traffic aircraft transitting the zone on a north-south line have more stringent restrictions.

i) Aircraft transiting the London zone via Ascot/Burnham should be not above 1000ft between Ascot and BUR NDB to remain well below the ILS. Arrivals into the zone using this route should enter at 1500ft; northbound traffic may climb to 2000ft after BUR. Both the SVFR transit and the IFR traffic should be closely monitored in case of deviation from the required route.

ii) When runway 27L or 27R is in use aircraft transiting the London zone via Battersea should be at 1500ft

iii) Between a north/south line through Battersea and a north/south line through Vauxhall Bridge , aircraft must not fly above 1500ft. Between the north/south lines through Vauxhall Bridge and London Bridge the maximum altitude is 2000ft. Transit through the London City zone can be offered Crystal Palace – Isle of Dogs – Lee Valley not above 2400ft, or remaining west of Vauxhall Bridge at 1500ft.


SVFR aircraft inbound to Heathrow or London City without a formal flightplan must be notified to the appropriate tower controller. Expected joining instructions and hand-off to TWR will follow standard VFR procedures.

If Thames requires to allocate an altitude above those specified in para 3.6 then co-ordination must be effected with:

  • EGLL_APP if Heathrow is on Westerlies
  • The relevant LON_CTR if Heathrow is on Easterlies
4: Maps

A detailed map of the Control Zones showing roads, railways and the River Thames can be downloaded from

Ruth McTighe
February 2004