Aircraft and Instrumentation

Since 1991 the MUMM has been carrying out its observation flights at sea using a twin-engine Britten Norman Islander. This reconnaissance aircraft, with the initial call sign “B-02”, was a military aircraft until 2005, based at the School for Light Aircraft in Brasschaat. It was specially equipped by the MUMM with sensors and other instruments for the mission. In 2005, when the Defence Ministry dispensed with aircraft of this type, the B-02 was transferred to the Federal Ministry for Scientific Policy and was allocated the new call sign ’00-MMM’.

With a flight range of five hours and an average cruising speed of 120 knots the Britten Norman Islander is ideal for regular surveillance trips over the North Sea. The aircraft also has two side blister windows, which considerably improve the visual observation of sea pollution and monitoring of marine mammals.

The aircraft is also equipped with a range of sensors and instruments that are essential to effectively carrying out its core mission, namely the detection of sea pollution. In 2012, after 20 years of air surveillance, the aircraft was fitted with a new, fully integrated and digital radar remote detection system that greatly speeds up the reporting of the various observations and therefore the follow-up. In 2016 the instrumentation was further expanded so as to also be able to monitor vessel emissions.

The most important sensor is the SLAR or ‘Side-Looking Airborne Radar’ which scans the sea surface to a distance of 20 km to the left and right of the aircraft (long-range sensor). The two black tubes beneath the aircraft are the SLAR’s lateral antennae which pick up reflected radar signals. A black line or blot on an SLAR screen, in marked contrast to the surrounding water (which appears on the SLAR image as a uniform grey colour) indicates possible sea pollution. The flattening effect of oily substances on the waves lies at the basis of this kind of remote detection. Mineral oil slicks or other floating substances with a similar dampening effect can be detected day or night, in poor visibility and at a great distance. Substances which are dissolved in the seawater and have no dampening effect on the waves and/or enter the water column are identified visually in most cases.



The infrared camera is a short-range sensor. Once a case of pollution has been detected remotely, whether by day or night, and the aircraft has flown to the area, an infrared camera can obtain an additional image of the slick. The infrared camera captures temperature differences between the slick and surrounding water. Thinner areas of the oil slick are portrayed as “cooler” as a result of evaporation while the thicker areas are portrayed as “warmer” due to the warming by the sun. The ability to distinguish between the thicker and thinner areas of an oil slick is particularly essential during oil fighting operations.

The aircraft is also equipped with a digital video camera and two digital cameras. If an authorised agent makes an observation at sea, it is important for this to be well documented. Clear photographs provide immediate visual confirmation. Digital photographs can also be sent quickly to services on standby at the quayside for further investigation or intervention at sea. Digital video images permit the continuous recording of an observation, when flying over an oil slick, for example, until reaching a suspect ship.

The GPS and the Flight Management System (FMS) permit a precise location and recording of time and date, wind speed and direction, vessel course and speed, and make radar communication possible by VHF.

The central MEDUSA control unit integrates the various sensors and sensor images and is also equipped with a digital nautical map and a built-in AIS receiver to identify ships automatically from a distance.

Since 2016 the aircraft has been equipped with an SO2 sniffer sensor. Using this new sensor the aircraft can detect sulphur concentrations in the smoke plumes of vessels. If suspicious values are recorded, a ship can be subject to a thorough technical port inspection as soon as it enters a European port.



  • Model : Britten Norman Islander

  • Call sign : OO-MMM (formerly ‘B-02’)

  • Length/height : 10.9 m/3.77 m

  • Wingspan : 14.02 m

  • Cruising speed : 120 kts (220 km/h)

  • Flight range : 5 hours

  • Max weight : 3000 kg

Britten Norman Islander OO-MMM



Instrument Model
SLAR Terma SLAR 9000
IR sensor FLIR A645
SO2 sniffer sensor IGPS sniffer system
Video camera Sony FDR-FX7
GPS - FMS Garmin GTN650 (x2) – Garmin G600
Photo cameras Nikon D7000 – Nikon D800
Control unit Optimare MEDUSA system (incl. ECDIS and Comar SLR200 AIS receiver)


Surveillance area

The surveillance area for the aircraft’s principal mission, the detection of sea pollution by oil or other harmful substances originating in vessels, was defined in the Bonn Agreement as the “Bonn Agreement Joint Responsibility Zone”. This zone lies between two north latitudes in the southern North Sea and includes Belgian marine areas and the adjacent waters of neighbouring countries. Within this Bonn Agreement Joint Responsibility Zone Belgium, the Netherlands, France and the United Kingdom are entitled to carry out regular pollution control flights. This section of the North Sea is also internationally recognized as one of the world’s busiest shipping areas, presenting a high risk of operational or accidental ship discharges than can quickly affect the interests of the four neighbouring coastal nations.

The fishery control flights and other national surveillance missions for the Belgian Coastguards take place over the Belgian marine areas, which consist of the Belgian territorial waters and exclusive economic zone (or EEZ), and ensure respect for the applicable regulations. Scientific monitoring also takes place principally over Belgian marine areas.

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zones legende en


The MUMM surveillance aircraft operates several days a week over the sea, day and night, during the week and at weekends. The aircraft stability and on-board instrumentation enable the aircraft to operate in fog and bad weather. Given the nature of the mission, the flight schedule is kept strictly secret.

During each surveillance flight a pre-planned and continually changing flight route is followed between fixed coordinates. B1, FB2, UKB, NH, etc. are the waypoints used for the flight planning. Depending on the observations made at sea it is of course always possible to depart from the planned flight route.

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The waypoints used to plan flights. The black line delimits the Belgian maritime area
(including territorial waters and the Exclusive Economic Zone).

Most slicks observed at sea are the result of shipping operations and are therefore referred to as operational discharges. The discharging standards are laid down in the MARPOL 73/78 Convention: Annex 1 of this Convention regulates discharges of mineral oil; Annex II regulates vessel discharges of other harmful liquids (so-called Noxious Liquid Substances or NLS); Annex V regulates the dumping into the sea of materials and waste from ships.

In the event of a collision at sea or other shipping accidents accidental sea pollution can arise, which is detected and documented in the same way from the aircraft.

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Manoeuvre to approach a vessel in order to identify it.
Adapted from Source: Oil pollution at sea, Securing evidence on discharges from ships. Manual, Bonn Agreement, 1993
Action points Action
1 Detection
2 Camera and SLAR detection
3 Saving SLAR images
4 Descent to 500 feet
5 - 8 Camera recording of the wake
9 Descent to 500 feet
10 Camera recording of the spill
11 - 13 Camera recording of the ship (name etc.)
14 Ascent to 500 feet
15 - 17 Recording of the data by the sensors (infrared, ultraviolet, etc.)
17 - 18 Saving of sensor images
19 Documentation and report, including radio conversations between aircraft and ship


Sea pollution by oil or other harmful liquids

During a routine pollution control flight the air operators try to observe any sea pollution visually and by means of sensors.

When mineral oil pollution is detected, the operator always makes an estimate of the quantity of oil that is drifting on the water surface. This estimated oil volume is important for evaluating the severity of the discharge and its impact on the marine ecosystem.

When operational sea pollution is detected, in many cases the polluter is unfortunately already far from the area…

When a vessel is caught in the act of an illegal operational discharge, the aircraft makes a manoeuvre to approach the ship and to identify the polluter. The mission is to follow in a safe manner, by day or by night, the pollution trace in the wake of the vessel and to fly alongside the vessel to read the name and home port on the hull, and to document all of this in real time. After such confirmations a flight report must be submitted to the Coastguard Central Office as soon as possible and further research initiated by the competent policing and judicial authorities.

operational discharge


Monitoring from the air of sulphur emissions by ships at sea

Since 2015 the MUMM surveillance aircraft has also begun monitoring the sulphur emissions of vessels at sea from the air (MARPOL Annex VI control flights). This activity started up as part of the CompMon project. To determine sulphur emissions by vessels at sea the aircraft must also be able to approach a ship’s smoke plume at low altitude and fly through it in order to take an air sample using the air tube on the aircraft fuselage. The sniffer sensor used for this purpose was tested over the sea in 2015 and fitted to the aircraft in 2016. To successfully sample a smoke plume, the direction and speed of the ship must also be taken into account as well as wind speed and direction. The sniffer sensor then analyses the sulphur content of the fuel used by the ship. If a suspicious sulphur value is measured this is recorded and reported to the port inspection service at the quayside that instigates further monitoring at the vessel’s next European port of call.

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Survey Station