UK Aeronautical Information Services

NATS Swanwick, Room 3115

Sopwith Way,

Southampton, SO31 7AY

01489 887462

01912 032329 (Distribution)


AIC for United Kingdom

Aeronautical Information Service


P 015/2020

Effective 12 MAR 2020


1 — Introduction

1.1 In accordance with UK procedures for the control of non-operational jamming, this circular gives notification of radio jamming activity, to intentionally provide interference and/or spoofing to Global Navigation Satellite System (GNSS) signals, which includes the Global Positioning System (GPS).
1.2 This Circular includes the details and locations of the GNSS jamming, description of the predicted impact area and a point of contact.

2 — Date, Times and Areas Affected

2.1  Date: 28 March – 09 April 2020 Inclusive.
2.2  Location: The jamming events will take place throughout the UK FIR/UIR north of 50 degrees North:
2.2.1 Overland and over sea off the West Coast of Scotland (Fast Jet Area South and South East);
2.2.2 Overland and over sea off the North coast of Scotland (Danger Areas and Fast Jet Area North).
2.3  Timing: There will be continuous, opportunity based and pre-planned events during the period.
2.3.1 Duration: Duration of activity dependent on location: Faraid Head - No Longer than 90 mins in duration and followed by an uninterrupted period of GPS service of no less than 60 mins; Loch Ewe – no longer than 60 mins duration and followed by an uninterrupted period of GPS service of no less than 60 mins.
2.4 Jamming will be limited to daylight hours and will not take place during times of restricted visibility.

3 — GPS Jamming

3.1 GNSS jamming will take place on the following frequencies:
3.1.1 1227.60 MHz (GPS L2)
3.1.2 1575.42 MHz (GPS/Galileo L1)
3.2 The following types of interference is planned:
3.2.1 GNSS denial of service only.
3.3 Text describing the predicted GNSS interference areas is supplemented with coverage graphics, representing the interference effect on GNSS receivers at 25 M AMSL, 5,000 FT AMSL, 20,000 FT AMSL, and 40,000 FT AMSL (And Above) from the jammer location. Graphics show the areas within which a GNSS receiver is likely to encounter jamming. No allowance is made for airframe masking or the reduction of antenna gain towards the horizon seen in all receiver systems. Therefore, the worst possible case for receiver vulnerability is considered.
3.4 Predictions show that the coverage area where GNSS signals are likely to be affected is as follows:
3.4.1 Faraid Head

Jamming events will take place from Faraid Head

583616N, 0044612W


36 NM in an arc 270°T clockwise to 100°T.

11 NM in all other directions.

5,000 FT AMSL

105 NM in an arc 285°T clockwise to 040°T.

25 NM in all other directions.

20,000 FT AMSL

140 NM in an arc 285°T clockwise to 040°T.

25 NM in all other directions.

40,000 FT AMSL (And Above)

140 NM in an arc 285°T clockwise to 040°T.

25NM in all other directions.

3.5  Loch Ewe

Jamming events will take place from Loch Ewe

575130N, W0054121


For shipping in the North Minch to 28 NM in an arc 285°T clockwise to 040°T

Areas of high ground with clear line of sight to an extreme range of 47 NM

5,000 FT AMSL

100 NM in an arc 330°T clockwise to 070°T.

50 NM in all other directions.

20,000 FT AMSL

140 NM in an arc 300°T clockwise to 095°T.

115 NM in all other directions.

40,000 FT AMSL (And Above)

135 NM in all directions.

4 — Use of GNSS

4.1 Although GNSS equipment is an accepted means of compliance with B-RNAV and P-RNAV requirements, one of the conditions of its use is that the aircraft must carry serviceable radio navigation equipment in order to allow reversionary means of navigation. Operators of aircraft should not rely on GNSS for B-RNAV and P-RNAV operations in the areas predicted to be affected by the jamming trials and should be prepared to revert to the alternative means of navigation.
4.2 For IFR en-route and terminal area operations, only radio navigation equipment required by the rules for IFR operations should be used.
4.3 For VFR operations, conventional means of navigation including dead reckoning should always be used. Operators of aircraft should be prepared for erroneous readings if cross checking with GNSS in the area predicted to be affected by the jamming trials.
4.4 Air Traffic Controllers should be alerted to the potential for aircraft to require navigation assistance during the period of the trial.

5 — Points of Contact

5.1 General (non urgent) queries regarding these trials should be made in the first instance to:

Stuart Rankin

Civil Aviation Authority

Aviation House

Gatwick Airport South

West Sussex


Tel: 03301-382919


5.2 During the period of the exercise, the formal cease jamming contact number is:

Cease jamming procedures to be published by NOTAM

This number is only to be used in case of emergency in order to ask for jamming to cease. As with previous exercises, safety of life operations will at all times take precedence over exercise activities.