INTAVAL is the MOD’s primary tool for the assessment of the vulnerability of air targets (aircraft, helicopters, missiles).  LMUK Ampthill has been responsible for its development, subsequent refinement and maintenance from its inception in 1979.

INTAVAL consists of a suite of computer models that enable the interaction between a weapon and the target to be addressed in detail, either from the point of view of target vulnerability or of weapon lethality.  Weapon types include proximity-fuzed missiles, direct hitting missiles, internally bursting shell and gun-fired shot.  Damage mechanisms include penetration and blast effects, plus secondary effects from fragment shatter, fires, explosions or hydraulic shock.  Damage is assessed at target component level and the functional response of the target is determined using a ‘survival tree’ logic.
The MoD has now initiated work on the successor to INTAVAL. This project, called the Unified Weapon Model (UWM), will be tri-service and will also bring together models from launch through to consequence. LMUK Ampthill is the Prime Contractor for the Weapon Target Interaction (WTI) module of UWM, leading a team of eight UK defence contractors. Current development work is focused on the modelling of the interception of ballistic missile targets.