Debrief was originally produced in 1995 in the Maritime Warfare Centre to act as a desktop viewer for results produced by the MWC's ASSET submarine simulator. In use it quickly became apparent that real exercise data could also be viewed in the application removing the requirement for clerical staff to produce paper plots for use in analysis. The initial version of Debrief was a 16-bit MS Windows C++ application.

Debrief was updated in late 1996 to 32 bits, in order to exploit the richer user interface components available for 32 bit Windows applications. It was at this stage that the application was demonstrated and subsequently issued under license to COMSUBDEVRON 12 of the US Navy.

In 1999 development of an updated version of Debrief, Debrief 2000 was started. Over the previous four years a number of fresh requirements had arisen, requirements which could not be economically met using the existing architecture. Accordingly development of the Debrief 2000 application started from a fresh-whiteboard, adopting a modern modular approach to allow incremental implementation and insertion of future modules as they were required. The rapid maturity experienced by Java together with the availability of cheaply available development environments, rich application libraries (serialisation, Java3D and XML in particular) and its platform independence made Java the natural choice for the application.

During 2000 Debrief gained wider use within the Maritime Warfare Centre, being used for more varied types of submarine exercise analysis together with analysis in surface-related warfare areas.

In Summer 2000 the Maritime Warfare Centre committed to switching the Debrief application to Open Source status. The adoption of the Open Source licensing model affects MWC in a number of ways:

At the end of 2000, Ian Mayo, the developer and project manager (see Table 1, “List of acknowledged Debrief users”) of Debrief, left full-time employment at the Maritime Warfare Centre to setup his own software development consultancy, PlanetMayo Ltd, now known as Deep Blue C Technology Ltd.

A competitive open tender process was conducted during late 2001 to supply the Maritime Warfare Centre with Debrief support. The contract was won by Deep Blue C, who grouped up the implementation of the MWC's fresh requirements in a major update to Debrief, titled Debrief 2001. This update bought new, large areas of functionality to Debrief including vectored chart data, display of narrative text, and display of sensor-data.

Debrief development continued in 2002, with the update to Debrief 2002, which bought greatly improved 3D plotting facilities and a number of incremental improvements to other areas of functionality.

The year 2002 also saw the first conference paper extolling the virtues of Debrief and the Open Source principles behind it, at Undersea Defence Technology 2002 in La Spezia, Italy. The paper itself is available for viewing at the Debrief web site.

Another significant step forward for Debrief in 2002 was the contribution from NUWC of an algorithm and code suitable for shifting tracks. NUWC developed a set of experimental classes used to perform track shifting (see Section 3.1.3, “Track shifting”). The algorithms used in these classes were taken and modified to complement the Debrief look and feel, and to provide greater usability resulting in the track-shifting editor included in Debrief 2002.

Through 2003-2007 Deep Blue C continued to provide MWC with contracted support for Debrief. This support included user guidance, bug fixes and addition of new features. Additionally, this support contract was used to deliver Debrief 2003 (including the provision of a bathymetric bottom in 3D views, presentation of TMA data, and improved time-variable graphs), and the fundamental rebuild of Debrief into Debrief NG (providing a modular architecture ready to seamlessly accommodate ad-hoc analysis tools).

In 2009 MWC extended Debrief to support Single Sided Reconstruction, that is the derivation of a Red track from a Blue track plus sensor data. These extensions also included Track Grooming changes that support the removal of jumps and general data smoothing.

2011 saw the introduction of support for plotting chart backdrops in GeoTiff format. Unfortunately, this exposed performance shortcomings in the render cycle and has been temporarily removed pending streamlining / cacheing of the render pipeline.

Charting support recommenced in Spring 2012, and a suitable implementation was found (See Chapter 10, Using chart backdrops). Support was also introduced for using Debrief in the process of Exercise Planning (See Chapter 8, Exercise planning).

In 2015, under DSTL sponsorship, support for the Natural Earth dataset and sponsorship for the development of Semi Automatic Track Construction, was added to Debrief. Both are of enormous value, the former to the wide body of Debrief users (see Section 7.1, “Natural Earth data”), and the latter to specialists interested in this small but select niche (see Section 12.3, “Semi-Automated TMA generation”).