CAP3319: CAA Publishes Guidance on Dual-Use Drone Testing and Multiple Simultaneous Operations

The UK Civil Aviation Authority (CAA) has published CAP3319, Guidance for Industry: Dual-Use UAS Development, Testing and Evaluation.

Published on 22nd October 2026, the document brings together the regulatory routes available for organisations developing unmanned aircraft and related technologies that could be used for both civil and defence purposes.

It covers testing under the Open Category, PDRA-01 and UK SORA, along with pre-assessed test sites, flightworthiness, counter-UAS testing and the division of responsibilities between the CAA and the Military Aviation Authority (MAA).

One section is particularly relevant to commercial operators: the CAA has now published guidance on how organisations can seek approval for Multiple Simultaneous Operations (MSO), where more than one unmanned aircraft is managed at the same time.

What is CAP3319?

CAP3319 is guidance for manufacturers, developers and operators undertaking UAS testing and evaluation. It is intended to help organisations choose a suitable regulatory route and gather evidence that may support later operational approvals.

The document is aimed particularly at dual-use technology. A company developing a navigation system, detect and avoid capability or autonomous aircraft for possible defence use may need to test it under civil aviation rules before any formal Ministry of Defence involvement.

CAP3319 explains how that can be approached using existing CAA frameworks.

It is not a new regulation or a general exemption for experimental flights. The normal operating category, authorisation and airspace requirements continue to apply.

New guidance for multiple simultaneous operations

Chapter 5, pages 26 and 27, covers Multiple Simultaneous Operations.

The CAA uses MSO to describe arrangements in which a single remote pilot, flight monitor or control system manages more than one unmanned aircraft concurrently. Examples include one-to-many operations, fleet operations, swarming and coordinated autonomous aircraft.

The CAA says MSO introduces additional risks that would not arise in the same way during conventional one-pilot, one-aircraft operations. These include remote pilot workload, the design of the human-machine interface, command and control arrangements, contingency management and failures affecting several aircraft at once.

CAP3319 states that MSO is assessed as an additional element of a Specific Category Operational Authorisation. The operator must demonstrate that the proposed arrangement manages the human and technical risks to an acceptable level.

How does the CAA recommend applying?

For developmental programmes, the CAA recommends starting with an authorised one-to-one operation for the aircraft and intended activity.

The operator should then gather evidence of aircraft performance, command and control, normal procedures and how abnormal situations are managed.

Once that baseline has been established, an operator outside a pre-assessed test site or permanent danger area is advised to seek MSO approval through a variation to its existing Operational Authorisation.

The variation must include an MSO Concept of Operations (ConOps) explaining how the additional complexity will be managed.

CAP3319 sets out a different starting point for operators working at a pre-assessed test site or in a permanent danger area. They may proceed directly to submitting an application or variation to the CAA.

The CAA recommends increasing aircraft numbers, tasks and autonomy progressively as evidence is collected. It also states that adding MSO to an existing UK SORA authorisation is a significant operational change requiring further assessment.

This guidance does not specify an acceptable pilot-to-aircraft ratio. Any approval will depend on the proposed operation and the evidence supplied.

Has the CAA changed its position on MSO?

The CAA's existing Operations covered by UK SORA webpage lists MSO among activities for which general policy has not been developed. It instructs prospective applicants to contact [email protected] before applying.

CAP3319 now provides a recommended assessment approach for developmental MSO programmes, including the possibility of a variation to an existing authorisation.

The two publications address different points. CAP3319 explains how the CAA recommends approaching a particular type of application; it does not establish a standard permission for MSO or remove the instruction to engage with the CAA.

Earlier in October, NATS reported that Wing had secured UK approval for one pilot to operate up to four drones. The conditions of that approval have not been published, and CAP3319 does not confirm whether Wing followed the route described in the new guidance.

Civil and military oversight

CAP3319 also explains how the CAA and MAA decide which regulator should oversee development work.

An aircraft intended for future defence use is not automatically exempt from civil aviation regulation. Where a dual-use system is flown in civil airspace without Ministry of Defence sponsorship, the CAA says its civil requirements apply.

The CAA and MAA use a joint process where the appropriate regulatory route is unclear. Relevant factors include who will operate and own the aircraft, its intended purpose, operating environment, payload and any planned transition to military service.

For organisations developing technology for both markets, the CAA recommends early engagement. The document says future editions will include further MAA guidance on the boundaries between civil and military testing.

Testing at pre-assessed sites

CAP3319 refers to the existing CAP3145 pre-assessed test site framework.

Under that framework, the CAA can pre-assess ground and air risks at a test site. Operators can use the relevant assessment when applying for a UK SORA Operational Authorisation, provided their proposed operation stays within the site's assessed conditions.

The framework can support VLOS and BVLOS testing up to SAIL II. It does not mean that an operator can simply arrive at a listed test site and fly without the appropriate authorisation.

CAP3319 also discusses the developing Light UAS Operator Certificate (LUC) approach, under which qualifying organisations could eventually self-authorise operations within agreed privileges. The publication does not itself grant those privileges or introduce a new general LUC application route.

Counter-UAS and intentional collision testing

Another section deals with testing aircraft interception systems, including intentional collisions between unmanned aircraft.

The CAA explains that the UAS regulatory framework does not expressly prohibit intentional aircraft-to-aircraft collisions. Operators must still comply with other applicable requirements, including Article 241 of the Air Navigation Order, which prohibits reckless or negligent endangerment of people or property.

The CAA expects most interception or collision testing to require a UK SORA-based Operational Authorisation because of the associated air and ground risks. Applicants should explain the aircraft involved, the intended interception, containment arrangements, airspace management and safety mitigations.

The guidance concerns controlled testing. It does not provide general approval to deploy counter-UAS interception systems operationally.

Testing flight termination systems and other mitigations

CAP3319 also gives examples of evidence that may be needed when testing flight termination systems, parachutes and geocaging.

For flight termination systems, it refers to BS EN 4709-006 as an example of a recognised standard. It discusses reliability evidence and the need to consider both termination and containment where a system is intended to support both requirements.

For parachutes, it refers to ASTM F3322-24a or equivalent standards and discusses descent rate, deployment time and the effect on ground risk calculations.

These sections describe considerations for generating technical evidence. They do not replace the applicable UK SORA requirements or the need to show that a mitigation works as intended on the aircraft concerned.

What does this mean for UK operators?

For most operators, CAP3319 does not change the permissions needed to fly.

Its main practical addition is the published advice for organisations developing MSO capabilities. The CAA recommends a staged approach based on a conventional authorised operation, evidence gathering and further assessment before multiple aircraft are introduced. Operators using pre-assessed test sites or permanent danger areas have a different recommended starting point.

Anyone considering MSO should continue to contact the CAA before applying, as instructed by its UK SORA guidance.

CAP3319 also gives manufacturers and developers a single reference for existing civil testing routes and for deciding when CAA or MAA oversight may apply.

The full publication is available from the CAA's CAP3319 page.