ARC Bridging BVLOS Drone Insurance UK

What ARC bridging means in a UK BVLOS context

Under the UK Open / Specific / Certified framework administered by the Civil Aviation Authority, every Specific-category operation is assigned an Air Risk Class (ARC) as part of the Specific Operations Risk Assessment (SORA) methodology. The ARC reflects the probability and severity of a mid-air collision with a manned aircraft, and it drives the required level of tactical mitigation — and therefore the operational envelope the CAA will authorise.

ARC bridging arises when an operator's SORA concludes that a lower ARC applies after applying strategic and tactical mitigations, but the carrier's aviation underwriter — reviewing the same operation for hull and liability rating — treats the residual risk as sitting in a higher ARC tier. The gap is not merely academic: it affects which Tactical Mitigation Performance Requirements (TMPR) the underwriter expects to see evidenced, and it can alter the liability limit structure the carrier is willing to deploy.

Bridging disputes are most common on corridor-based infrastructure inspection and beyond-visual-line-of-sight delivery trials, where the operator has invested heavily in detect-and-avoid technology to achieve a lower ARC, but the underwriter has not yet received — or does not accept — the evidence package that supports the mitigation credit.

Why carriers and OA holders reach different ARC conclusions

The CAA's SORA guidance allows operators to claim ARC reduction through a combination of strategic mitigations (airspace design, operational volume restrictions, time-of-day constraints) and tactical mitigations (detect-and-avoid systems, ground-based observers, real-time airspace monitoring). Each mitigation layer must be evidenced to a defined robustness level. Carriers apply their own technical review of that evidence, and their assessment does not automatically mirror the CAA's authorisation decision.

A common source of divergence is the treatment of detect-and-avoid (DAA) system performance data. An operator may hold a CAA-accepted CONOPS citing a DAA solution that achieves the required TMPR robustness level, but the carrier's aviation underwriter may not have seen the underlying test data, may be applying a different failure-mode assumption, or may be working from an outdated version of the SORA guidance. Similarly, operators sometimes present an OA that was granted under a bespoke arrangement rather than a standard PDRA, making direct comparison with the carrier's rating model difficult.

Regulatory timing also plays a role. The CAA may have accepted a novel mitigation approach that the Lloyd's or company-market underwriter has not yet incorporated into their technical guidelines. In those cases the carrier is not wrong to ask questions — they are simply working from a more conservative baseline until the evidence is shared.

• DAA performance data not yet submitted to the carrier
• Operator SORA uses a bespoke OA rather than a published PDRA, reducing comparability
• Carrier's internal ARC matrix predates the current CAA SORA version
• Strategic mitigation credits (e.g. restricted airspace corridors) not reflected in the carrier's geographic data
• Conflicting assumptions about operational volume versus contingency volume

The broker's role in resolving an ARC bridging dispute

The broker is the natural intermediary between the operator's safety team and the carrier's aviation underwriter. Resolving an ARC bridging dispute is primarily a document and dialogue exercise, not a negotiation over price. The broker's first task is to obtain the complete SORA evidence package from the operator — including the CONOPS, the DAA system performance summary, the airspace assessment, and the CAA OA itself — and present it to the underwriter in a structured submission rather than as a collection of attachments.

Where the carrier's objection is specific — for example, a challenge to the robustness level assigned to a particular tactical mitigation — the broker should request a written technical query from the underwriter and route it to the operator's qualified entity or in-house safety manager for a formal written response. This creates an audit trail that protects all parties and often resolves the dispute faster than informal calls.

If the carrier maintains a higher ARC assessment after reviewing the full evidence package, the broker has three practical options: seek a co-insurance arrangement where a second carrier accepts the operator's ARC and leads the programme; place a difference-in-conditions layer that addresses the gap between the two ARC positions; or return to the operator with a recommendation to strengthen the mitigation evidence before the next placement window. Brokers should document which option was pursued and why, particularly where a flight programme is time-critical.

Insurance coverage considerations when ARC tiers are in dispute

Hull and liability coverage for BVLOS operations is structured around the operational envelope described in the OA. If the carrier has rated the policy on a higher ARC assumption than the OA reflects, there is a risk of misalignment between the insured scope and the actual operation — which can affect claims handling if an incident occurs during a flight that the carrier believed carried greater residual air risk than the operator's SORA concluded.

Liability limits for Specific-category BVLOS operations are typically quoted in GBP and must meet the minimum requirements set out in UK Regulation (EU) No 785/2004 as retained in UK law, which references Special Drawing Rights as the unit of account. Operators and brokers should confirm that the limit structure agreed with the carrier is consistent with the ARC tier the carrier has underwritten — not the tier the operator believes applies — until the bridging dispute is formally resolved.

Hull coverage terms, including deductibles and exclusions for autonomous flight modes, often tighten when the carrier assigns a higher ARC. Operators should review the policy schedule carefully to identify any endorsements that restrict coverage to specific flight modes, geographic corridors, or DAA system configurations, as these may not match the operational parameters in the OA.

Preventing ARC bridging disputes at placement

The most effective way to avoid an ARC bridging dispute is to involve the carrier's technical team early — ideally before the SORA is finalised and submitted to the CAA. Some specialist BVLOS underwriters will review a draft CONOPS and provide a non-binding ARC assessment, which allows the operator to identify any divergence before the OA is issued and before the insurance placement is time-pressured.

Operators applying for a Predefined Risk Assessment (PDRA) authorisation have an advantage here: PDRAs carry a published ARC and a defined set of mitigations, which gives carriers a clear reference point. Bespoke OA holders should prepare a concise technical summary that maps their SORA mitigations to the PDRA framework where possible, even if the operation does not qualify for a PDRA, to give underwriters a familiar structure to assess.

Annual renewal is a natural checkpoint. If the operation has evolved — new corridors, higher MTOM aircraft, upgraded DAA systems — the broker should submit an updated SORA summary at renewal rather than relying on the prior year's submission. Carriers that have not been kept informed of operational changes are more likely to apply conservative ARC assumptions.

• Submit the full SORA evidence package at inception, not after binding
• Request a pre-placement technical review from the carrier where the operation is novel
• Map bespoke OA mitigations to the nearest PDRA for carrier reference
• Update the carrier at renewal whenever the operational envelope has changed
• Agree a written ARC position with the carrier before the policy is issued

Frequently asked questions

Does my Operational Authorisation automatically determine the ARC my insurer uses?

No. The CAA's acceptance of your SORA and the ARC it reflects is a regulatory decision. Your carrier's underwriter conducts an independent technical review and may reach a different ARC conclusion based on the evidence available to them at the time of placement. The two assessments can diverge, and it is the broker's role to close that gap by sharing the full SORA evidence package with the underwriter.

What coverage does a BVLOS hull and liability policy typically include?

A Specific-category BVLOS policy typically covers physical damage to the UAS hull, third-party bodily injury and property damage liability, and — depending on the carrier — payload liability and ground equipment. Coverage is scoped to the operational envelope described in the OA. Autonomous flight modes, BVLOS corridors, and specific DAA system configurations may be subject to endorsements. Operators should review the schedule to confirm that the insured scope matches the authorised operation.

Which operators are eligible for BVLOS insurance in the UK?

Eligibility is assessed on a case-by-case basis. Carriers generally require a valid CAA Operational Authorisation for the Specific category, a completed SORA or PDRA reference, evidence of pilot competency (typically a GVC or higher qualification), and documented maintenance and airworthiness records for the UAS. Operations using novel DAA systems or flying in complex airspace may require additional technical evidence before a carrier will offer terms.

What is the broker workflow for placing a BVLOS programme?

The broker collects the operator's OA, CONOPS, SORA summary, pilot records, and UAS specifications, then prepares a structured submission for specialist aviation carriers. Where the operation is novel or involves a bespoke OA, the broker may request a pre-placement technical dialogue with the underwriter. Once terms are agreed — including a confirmed ARC position — the policy is issued and the operator receives a certificate of insurance that can be presented to the CAA or a client as evidence of cover.

What regulatory triggers require a BVLOS operator to notify their insurer mid-term?

Material changes to the operational envelope typically trigger a notification obligation under the policy conditions. These include: a change in the geographic corridor or operating area, an increase in the MTOM of the UAS, a change in DAA system or pilot-in-command, an amendment to the CAA OA, and any incident or near-miss that may give rise to a claim. Operators should review their policy's notification clause and contact their broker promptly when any of these changes occur, as operating outside the notified scope can affect claims validity.

Can a co-insurance structure resolve an ARC bridging dispute?

Yes, in some cases. Where one carrier accepts the operator's ARC and another applies a higher tier, a co-insurance arrangement can be structured so that the leading carrier's ARC position governs the primary layer and a following carrier's terms are aligned accordingly. This requires careful drafting to avoid gaps between the two carriers' coverage positions. A difference-in-conditions layer is an alternative where the gap between ARC assessments is narrow and well-defined.