EU OPEX will launch its main testing phase in Portugal on 28 September. As part of the European-Defence-Agency (EDA)-run operational experimentation exercise, five European loitering munition manufacturers will compete for €1.8 million in prizes in the second stage of EDA’s Sentinel Strike Challenge.
Sentinel Strike is a prize competition rather than a procurement program, meaning victory does not automatically result in an EU weapons contract. But it’s an important staging post, letting the startups show off what they can do to national representatives who will play a significant role in their countries’ procurement processes – and it lets those startups stack up their technology against their rivals.
The systems competing weigh no more than 25kg and have an operational range of up to 40km.
Stage 1 consisted of a competitive technical proposal assessment. The top five – Helsing, Destinus, C-Astral, UAVision, and Spirit Aeronautical Systems (SAS Technology) – each received a €30,000 prize and advanced to Stage 2.
Stage 2 is operational field testing at the Santa Margarida Military Training Area in Portugal. The trials will take place as part of EU OPEX26, alongside the Portuguese Army’s ARTEX26 technological experimentation exercise.
The systems will be evaluated across the full precision-strike mission cycle. The loitering munitions will also be tested for resilience in degraded and contested environments.
Pre-trial system acceptance and safety testing began this week and runs through Friday, 25 September.
The main experimentation phase is then scheduled for 28 September to 9 October.
“Defence innovation produces no shortage of promising systems. The harder problem is generating evidence that allows military users to compare them properly: same operational problems, comparable conditions, real users and enough experimentation to discover where the brochure stops matching reality. Testing before investing sounds obvious, but doing it properly takes considerably more work than the slogan suggests,” Tim De Zitter, a lifecycle manager at Belgian Defence, wrote on LinkedIn.
Startups Stage 2 winners are expected to be announced in early 2027.












