According to a press release published on the Finnish Ministry of Defence website on February 24, the Finnish Defence Forces (FDF) have been authorised to order an additional 155 mm BONUS Mk II (BOfors NUtating Shell) anti-armour artillery from French contractor Nexter. The FDF has had 155 mm BONUS rounds in stock since 2014, and while the press release does not specify the quantities to be contracted, the total value of the procurement is estimated to be around EUR 35 million.
The BONUS project began in 1985 as a study project for the Swedish Defence Materiel Administration (Försvarets materielverk/ FMV). The goal was to find a way to improve artillery"s effectiveness in engaging enemy armoured units. Development was completed in 1992 through collaboration between Bofors (now BAE Systems Bofors) in Sweden and Nexter in France, with the French and Swedish armies introducing the munition into service in 2000. Since then, both BAE Systems Bofors and Nexter have produced the BONUS round.
While neither the BONUS carrier shell nor the submunitions are guided, the combination of two submunitions per shell, the broad search pattern of the submunition sensors, and the use of the sensors to trigger the warhead significantly increase artillery"s ability to engage hostile heavy armour, to the point where BAE Systems Bofors claims a probability of hit greater than one target per shell. The BONUS is conceptually similar to the German 155mm SMArt artillery round. The primary difference is that SMArt submunitions use parachutes instead of wings during their descent and target scanning phase. Norway, like France, Sweden, and Finland, employs BONUS rounds. France has also donated them to Ukraine.
