Intelligence, surveillance and reconnaissance, or ISR: there is a lot of technology wrapped up in those three letters, and while the global requirement for ISR systems is still growing, in numbers and capability, there is no hard definition as to what it really is. Each end-user struggles to specify exactly what he needs, balancing the requirements of his missions against available aircraft; the state of current products; and the costs of the upgrade of his airborne platforms, any necessary upgrades to the infrastructure with which it needs to interface, and any additional support for the new ISR system.

So how can we define the basic requirements of ISR?


Intelligence is the processed data derived from the other two mission systems as integrated into the operations network, typically ground based. It is the very reason the mission requirement exists: to gather sufficient data so that accurate, current and actionable intelligence can be derived and disseminated to the agencies that need it.

An intelligence system requires interfaces to the:

  • sensor and platform subsystems
  • processors that filter the mass of sensor data in order
  • to create the required data for the mission
  • recorders that store the data for post-mission processing
  • communications systems that disseminate the right information to the right people at the right time.

The type of interfaces, processors, recorders and communications systems are determined by the unique requirements of each end-user – every end-user starts with a different baseline of existing infrastructure and unique sensor and mission management network requirements.


Surveillance is the act of discretely gathering real-time situational information over a predefined area, and usually involves a predefined set of target types, which are the focus for a predefined period.

The predefined area can be a point in space (for example. a meeting location), a line (a road or border), an area (a city) or even a volume (airspace above a war zone). Target types can be an object such as a briefcase, an individual, vehicles, groups (such as an attack team), an RF transmission, an event or something out of the ordinary (from disturbed earth to unusual movements or gunshots). The predefined period can be a specific time of day, a specific length of time or an indefinite period (until something of note is detected).

From an airborne perspective, sensors typically used are long-range, real-time imagers (visible spectrum, long, mid or short wave, or the specific frequency range of infra red), radar, imaging systems (such as LiDAR or multispectral scanners), RF scanners and direction finders. Sensor data is usually observed in real time by on or off-platform operators, and is typically geo-referenced for real-time processing and post-mission analysis.


Reconnaissance is the gathering of detailed information about a specific area to assist in the preparation of a mission, typically a troop movement or assault. Such information includes weather, terrain, building locations, vehicle and personnel density, activity and movements. The same surveillance sensors and systems are typically used, although stealthy passive remote sensors may be more critical due to the need for the protection of personnel.

Airborne platforms used may be rotary, fixed wing or airships (manned or unmanned). The platforms are as varied as the sensors and other ISR equipment used, and each integration is customised to each platform.

ISR capability implementation

Establishing an ISR capability on an existing airborne platform (or fleet) is a significant process. The platform will affect the cost of implementation and operations, range and duration of missions, and weight and power limits, among other critical parameters. Ergonomically, smaller platforms are more appropriate for contortionists when integrated with a full ISR suite. Larger platforms (the CN235 or C130) not only allow for greater range and capability (not to mention ergonomically superior operator environments), but also enable the use of ro-ro modular mission suites (such as SABIR) that provide greater mission options and flexible mission profiles, while also cutting modification costs.

Sensors selection is driven by mission needs, but typically includes at least a stabilised long-range high-definition EO/IR imaging system (Wescam MX15 or FLIR Star SAFIRE) and radar (Telephonics or Selex). A 2D or 3D terrain scanner, an RF scanner and/or direction finder, a mission workstation (such as Z-Microsystems) with software (for instance, Cartenav AIMS or CLAW), some operator displays (Barco or Avalex), some LOS communications equipment (such as COFDM – coded orthogonal frequency division multiplexed), some OTH communications equipment (satcom, for example), video and data recorders, AIS, and any other specific equipment or subsystems required by the mission profile should be added.

The ranges, resolutions, sensitivities and other critical parameters of the sensor systems are also driven by the end-user’s mission requirements and environments, and the level of performance may be limited by end-user location or use, possibly incurring technical limitations due to international export restrictions. Supportability and political sensitivites within the region also affect sensor selection.

Finally, just when the end-user has determined the right balance for all the above parameters, they may find they do not have the budget for the ideal system, so they have to start compromising performance against inclusion of mission elements, thereby limiting overall mission capability.

Achieving interoperability

As if these challenges were not enough to weaken the knees of any mission commander faced with a required upgrade of his squadron’s ISR capabilities, he also has to consider the interoperability of the systems with his existing mission support infrastructure (and with that of his coalition partners).

There are few standards on which he can rely to do this. The way the data is processed, transmission protocols, and compatibility of his data and encryption method with other mission data systems – even the compatibility of his mapping systems with the mission workstation software itself – may severely limit his choice.

Once he has overcome all of these challenges, it is not unusual to drive the implementation of one ISR solution across a range of aircraft fleets to simplify the overall system upgrade in terms of training and support (including spares). Often an airborne ISR upgrade can be completed and operational before the ground communications infrastructure upgrades required to support the new airborne ISR system are even started.

The final touches

When the budgets are finalised and financial challenges arise, the adjustments are usually done by dropping subsystems rather than degrading the performance of a specific subsystem. The baseline is usually the EO/IR or radar and mission workstation. Communication systems are added as budgets allow because they are not fully operational until the equivalent compatible system is added to the ground network infrastructure, which usually falls under another budget at another time.

Satcom is the last item to be added as it is the most expensive for air and ground infrastructures, and typically provides more limited bandwidth, although unlimited coverage throughout the satellite’s footprint is a large advantage.

Supportability elements are frequently not considered as a major part of the procurement unless the commander has had problems in the past, and are covered by a separate budget.

Airborne ISR upgrades and retrofits are not for the faint of heart, and the lack of standards further complicates the process. At the end of the day, budgets drive the final decisions. The ideal solution is rare, but ISR platforms pared down for very specific mission profiles are common; there are even standard complete ISR platforms available for purchase or lease. Further upgrades can, of course, also be implemented when new mission requirements present themselves.