Autonomous and automatic air-to-air refuelling

The European Defence Fund call EDF-2026-RA funds research actions to develop sensor systems, sensor fusion, optical sensing, image processing, flight control algorithms and pilot assistance interfaces for autonomous probe-and-drogue air-to-air refuelling to enable precise relative navigation and manned-unmanned teaming. Multi-beneficiary consortia are mandatory, typically requiring at least three independent legal entities from three EDF-eligible countries (EU Member States and Norway); the topic has an indicative budget of €20 million and funds Research Actions at 100% of eligible costs with equipment reimbursed via depreciation. Proposals must target technology maturation up to TRL 6, include studies, design and knowledge integration, and demonstrate technologies through simulation and flight tests with a dry-contact demonstration; boom technology is excluded. Submissions are single-stage via the EU Funding & Tenders Portal with a deadline of 29 September 2026, 17:00 Brussels time, and applicants must comply with EDF security, ownership and ethics requirements.

Autonomous and automatic air-to-air refuelling (EDF-2026-RA-AIR-A4R)

What the call funds

Research activities (studies, design, knowledge integration up to TRL 6) that develop and test sensor systems, sensor fusion, optical sensors, image processing, flight control algorithms, pilot assistance interfaces and CONOPS for autonomous and automatic air to air refuelling of manned and unmanned receivers. Flight test data capture (dry and wet contacts) and standardisation outlines are expected.

Who can apply

Consortia of legal entities established in EDF eligible countries (EU Member States and Norway as an associated country). Multi beneficiary applications are mandatory. Subcontractors and associated partners may participate under EDF rules; participation by non EU entities is subject to strict conditions and security guarantees. Applicants must follow EDF security, ethics and eligibility rules and submit via the Funding & Tenders Portal Funding & Tenders Portal.

Deadline:29 September 2026, 17:00 Brussels time.

Indicative funding available:€20 000 000 indicative budget for this topic within the EDF-2026-RA call; the overall EDF-2026-RA call budget is about €110 000 000 ¹.

1. 1Type of action: EDF Research Actions implemented via actual cost grants. Funding rate for research actions is 100%
2. 2Eligible activities: generating knowledge, studies, design; prototyping, testing, qualification and certification are generally not funded under this topic
3. 3Security: projects may generate classified information and must comply with EDF security rules (PSI) and national facility and personnel clearance requirements

Start the submission in the Funding & Tenders Portal. Read the call document and annexes carefully for admissibility, eligible countries, consortium composition, budget rules (equipment depreciation, indirect costs options), security and required templates before applying EDF Topic Page. ¹

Footnotes

1. 1Call document, topic description, conditions, templates and submission entry are available on the Funding & Tenders Portal topic page: EDF Topic Page.

Autonomous and automatic air-to-air refuelling (EDF-2026-RA-AIR-A4R) — Call for Proposals Overview

Programme: European Defence Fund (EDF) — Research actions implemented via actual cost grants (EDF-2026-RA). Type of action: EDF-RA (EDF Research Actions). Model Grant Agreement: EDF Action Grant Budget-Based [EDF-AG]. Deadline model: single-stage. Opening date: 11 February 2026. Deadline: 29 September 2026 at 17:00 Brussels time. Submission via the EU Funding & Tenders Portal.

Scope, Objectives and Expected Outcomes

Air-to-air refuelling (AAR) is critical to mission endurance and reach. Today’s operations rely on manual coordination between tanker operators and receiver pilots, which is complex and labour-intensive. This topic advances automated and autonomous AAR to reduce crew workload, increase safety, and enable refuelling of future unmanned aircraft. It directly contributes to the Strategic Technologies for Europe Platform (STEP) in defence technologies.

Specific objectives:Explore, develop and adapt up to TRL 6 sensors, sensor fusion, data exchange and control technologies to enable precise relative navigation between tanker, receiver(s) and refuelling equipment (probe-and-drogue), including in adverse conditions. Design and validate enhanced optical sensing and image processing, flight control algorithms and supervision interfaces that improve docking and refuelling safety and time efficiency for manned and unmanned aircraft.

Targeted outcomes:Receiver autopilot functions enabling autonomous AAR; interoperable sensor fusion and data links between tanker and receivers; an A4R concept of operations (CONOPS) for multi-receiver scenarios including unmanned aircraft; a standardisation outline proposal for autonomous AAR; technology demonstrations including flight tests (dry contact mandatory, wet contact desirable) to collect validation data; enhanced visual tracking and processing systems for autonomous approach and docking.

Activities, TRLs and Work Content

Mandatory tasks:Integrating knowledge: Define an A4R CONOPS ensuring interoperability in international operations. Studies: Integrate sensor systems (hardware and fusion) for precise relative navigation among tanker, receiver and refuelling system, including in adverse conditions and EMCON; assess optical sensors and image processing; develop a standardisation outline for A4R; produce a technical and functional evolution roadmap for autonomy on current and future tanker and receiver aircraft; identify hardware and fusion challenges for accurate relative navigation. Design: Design flight control modes and algorithms, crew interfaces and assistance, and actively controlled or stabilised drogue systems to facilitate docking and refuelling, improving safety and time efficiency; for unmanned receivers, design a higher-level mission management system enabling full autonomous AAR with multiple aircraft; make available or develop test environments and procedures across lab components, integrated simulators, sub-scale and full-scale flight tests.

Should-cover tasks:Studies: Integrate AI in search and tracking, flight control modes and algorithms, pilot interfaces and drogue stabilisation, showing a credible pathway towards certification; develop navigation sensor fusion and relative position algorithms; specify special requirements for tanker/receiver communications, data links and telemetry for autonomous AAR that can be integrated into current and future manned and unmanned aircraft. Flight demonstrations: Dry contact required; wet contact demonstration desired to gather verification and validation data; visual tracking and processing demonstration for autonomous operations as per the CONOPS.

Optional tasks:Computing technologies: Identify computing capabilities needed to integrate autonomous AAR in real operational environments.

Target TRL progression:Adaptation and maturation up to TRL 6 in representative environments for key subsystems and algorithms, supported by simulation, sub-scale and flight tests.

Functional Requirements and Interoperability

• Automatic and autonomous modes for AAR operations.
• Support teaming of manned and unmanned aircraft and multiple refuellings per mission.
• Reliable operation across receiver flight envelopes and in adverse weather and night conditions.
• Compatibility and integration with existing aircraft systems.
• Interoperability with applicable standards, for example ATP 3.3.4.10, and between refuelling assets.
• Provision of monitoring and supervision features to assure safety.
• Data links and telemetry supporting autonomy with EMCON and contested environments considered.

Expected Impact

• Higher safety and reliability of AAR operations.
• Reduced aircrew workload and lower mission cancellation rates.
• Faster, more efficient refuelling cycles.
• Progress towards standardisation and interoperability of AAR procedures and systems.
• Enablers for manned-unmanned teaming in air operations.
• Contribution to EU strategic autonomy by reducing or preventing strategic dependencies.

Eligibility, Consortium and Country Conditions

Eligible Applicant Types:Public or private legal entities established in EU Member States or in the EDF associated country Norway and having their executive management structure in these countries. Typical applicants include SMEs, mid-caps, large enterprises, prime contractors, avionics and sensor suppliers, software and AI firms, universities, research and technology organisations, and public research institutes. Defence ministries and governmental entities may participate within EDF rules. Entities controlled by non-associated third countries may participate only under strict guarantees approved by national authorities, ensuring no contravention to EU security and defence interests; they are generally not eligible for EDF funding.

Consortium requirement:Multi-beneficiary applications are mandatory. While the call document details the exact composition rules in section 6, EDF research actions typically require a cross-border consortium with at least three independent legal entities established in at least three different EU Member States and/or Norway. Subcontractors and associated partners can be included as per EDF rules; associated partners from non-eligible countries may participate under strict conditions and without EDF funding.

Geographic eligibility:EU Member States and Norway (EDF associated country). Recipients and subcontractors involved in the action must be EU- or Norway-based, with executive management in those countries. Work, equipment and assets must be located in eligible countries throughout the action; limited exceptions apply but would be ineligible for reimbursement and subject to strict safeguards.

Mentioned countries and regions:EU Member States; Norway.

Funding, Cost Eligibility and Financial Conditions

Funding type and rate:Grant. EDF Research Actions are funded at up to 100% of eligible costs.

Indicative budget:€20,000,000 for this topic. Several proposals may be funded. The budget year contribution for the overall EDF-2026-RA multi-topic package is €110,000,000.

Cost eligibility highlights:Actual costs under a budget-based grant; indirect costs at 25% flat-rate or as actual indirect costs if national authorities certify usual accounting practices for defence; depreciation only for equipment costs under this topic; VAT is generally ineligible if deductible; subcontracting must follow best value for money and EDF limitations; Financial Support to Third Parties (cascade funding) is allowed within ceilings set in the call and Annex 4. For details see the EDF/ASAP/EDIRPA Model Grant Agreement and the call document.

Co-funding requirement:For Research Actions, the EU funding rate is 100% of eligible costs; co-funding is not generally required, though non-eligible costs, VAT (if deductible), and any costs outside eligibility must be covered by applicants.

Application, Evaluation and Timeline

Application type and stages:Open call, single-stage submission through the EU Funding & Tenders Portal. One stage of proposal evaluation followed by grant agreement preparation for selected proposals.

Evaluation framework:Award criteria, scoring, thresholds and the submission/evaluation processes follow sections 8 and 9 of the call document. Security scrutiny applies as needed. Priority order rules for same-score proposals apply. Business coaching may be offered to successful SME beneficiaries.

Success rates:No success rate information is provided for this topic; competition is expected to be high given the indicative budget and the number of proposals foreseen.

What to Deliver: Technical and Standardisation Content

• A4R Concept of Operations (multi-receiver, manned and unmanned).
• Integrated sensor system architecture and sensor fusion for precise relative navigation under adverse conditions; EMCON considerations.
• Optical sensors and advanced image processing for drogue and receptacle tracking; visual tracking demonstration.
• Flight control modes/algorithms and actively controlled or stabilised drogue system designs to increase safety and time efficiency.
• Crew interfaces and pilot assistance tools with supervision/monitoring features.
• Autonomy enablers for unmanned receivers, including mission management for multi-aircraft AAR.
• Data links and telemetry requirements for autonomous AAR compliant with current and future platforms.
• Standardisation outline proposal for autonomous AAR and regulatory/certification pathways, including AI considerations.
• Laboratory, simulation, sub-scale and flight test plans and results, including dry-contact demonstration and data; wet-contact desirable.
• Roadmap for technical and functional evolution towards operational integration on tankers and receivers.

Security, Ownership and Compliance

• Security and eligibility conditions are strict: beneficiaries and core subcontractors must be established in eligible countries with executive management located therein.
• Entities controlled by non-associated third countries require ownership/control guarantees approved by competent national authorities using the Ownership Control Guarantee template; otherwise they may be excluded.
• If Galileo PRS information is needed, the PRS declaration by competent authorities must be included.
• Background and results must remain free from control or restriction by non-associated third countries; technology transfer controls apply.
• Classified information handling complies with the EDF Programme Security Instruction (PSI) and the Model Grant Agreement annexes.

Templates and Application Package Structure

Core application structure (Part A and Part B):Part A is completed online in the Portal: administrative data, consortium, budget, declarations. Part B is a narrative technical description uploaded as a single AES-256 encrypted, password-protected zip archive. Observe page limits and formatting set in the call document. Part B includes: 1) Excellence and potential of disruption; 2) Innovation and technological development; 3) Competitiveness; 4) EDTIB autonomy; 5) Creation of new cross-border cooperation; 6) Lifecycle efficiency (n/a for RAs); 7) Member State cooperation (n/a for RAs); 8) Implementation with work plan, WPs, resources, risk management and communication; 9) Ethics and Security; 10) Declarations.

Key annex templates to include where applicable:Participant information: legal and operational profile, key staff, relevant projects, affiliated entities/associated partners, and security/ownership explanations. Location of infrastructure, facilities, assets and resources: full addresses, ownership, FSC status, and justifications if outside eligible countries. Actual indirect cost methodology declaration: details of usual accounting practices, cost elements, apportionment keys/bases, adjustments and at least two comparable national defence projects; signed by national pricing authority. Ownership control guarantee: measures ensuring no undue foreign control or access to sensitive information or IPR; requires competent authority approval. PRS declaration: confirmation by competent PRS authority if Galileo PRS access is needed. Detailed budget table (EDF RA): by participant, budget category, and activity types aligned with WPs. Model Grant Agreement (EDF/ASAP/EDIRPA) terms apply post-selection.

Administrative and Legal Particulars

• Equipment costs: depreciation only under this topic; rental/leasing eligible within depreciation-equivalent limits; no financing fees.
• Subcontracting: must not cover core tasks or WP leadership; normally should be limited and justified; best value for money; strict limits may apply in certain calls.
• Financial Support to Third Parties: allowed within ceilings; must define purpose, eligibility and selection procedures; costs managed under D.1 and excluded from indirect cost base.
• Indirect costs: 25% flat-rate of eligible direct costs (excl. volunteers, subcontracting, FSTP, and exempted categories) or actual indirects via certified methodology.
• Security scrutiny and potentially classification of deliverables; dissemination levels set during grant preparation.
• No letters of support from Ministries required for RA calls; equal treatment rules apply.
• Business coaching may be offered to successful SMEs.

Categorisation Answers

Eligible Applicant Types:SMEs, mid-caps, large enterprises, aerospace primes and tier suppliers, universities, research and technology organisations, public research institutes, nonprofit research bodies, and government entities involved in defence R&D. Subcontractors and associated partners can include specialised firms and laboratories. Startups are eligible and welcome; financial capacity is checked at grant preparation stage.

Funding Type:Grant (budget-based, actual costs), EDF Research Actions at 100% funding rate for eligible costs.

Consortium Requirement:Consortium. Multi-beneficiary applications are mandatory; cross-border composition per EDF rules (typically at least three independent entities from three different EU Member States and/or Norway).

Beneficiary Scope (Geographic Eligibility):EU Member States and Norway (EDF associated country). Executive management must be in eligible countries; strict rules on ownership and control by non-associated third countries.

Target Sector:Defence aviation; systems engineering; sensors and sensor fusion; optical sensing and image processing; flight control and guidance; autonomy and unmanned systems; avionics and data links; safety and certification. Cross-cutting enabling technologies include AI and software, communications, and human-machine interfaces.

Mentioned Countries:EU Member States; Norway.

Project Stage:Development, validation and demonstration up to TRL 6 in representative environments, including simulation, sub-scale and flight test demonstrations (dry contact mandatory; wet contact desirable).

Funding Amount:Indicative topic budget €20,000,000; several proposals may be funded. Per-project grant sizes will depend on the number and quality of proposals and the topic budget.

Application Type:Open call, single-stage electronic submission via the EU Funding & Tenders Portal.

Nature of Support:Financial support (grant). Non-financial support includes potential SME business coaching.

Application Stages:1 stage (single-stage submission and evaluation), followed by grant agreement preparation for selected proposals.

Success Rates:Not specified for this topic.

Co-funding Requirement:No co-funding required for eligible costs under EDF Research Actions (funding rate 100%). Applicants must cover any ineligible costs and ensure liquidity for project cashflow if prefinancing does not cover all early expenditures.

How to Apply and Key References

• Start submission: select EDF Research Actions [EDF-RA], EDF Action Grant Budget-Based [EDF-AG] on the portal.
• Refer to the 2026 Call Document, especially sections 5-10 (admissibility, eligibility, award criteria, legal and financial set-up).
• Use the Standard Application Form (EDF), Detailed Budget Table (EDF RA), Participant Information, List of Infrastructure and Facilities, Actual Indirect Cost Methodology Declaration, Ownership Control Declaration/Guarantee, PRS Declaration (if applicable).
• Consult the EDF, ASAP and EDIRPA Model Grant Agreement for cost eligibility, reporting, security and IPR provisions.
• Guidance resources: Funding & Tenders Portal Online Manual; Rules for Legal Entity Validation, LEAR and Financial Capacity; EU Grants AGA — Annotated Model Grant Agreement; EDF Programme Security Instruction (PSI).
• Partner search and announcements available on the portal; NFPs can assist with consortium building.

Practical Tips for Applicants

• Align your work packages strictly with eligible activity types (b, c, d) and show TRL progression towards TRL 6 through simulation, lab, sub-scale and flight testing.
• Plan for at least a dry-contact flight test and explain constraints, risk mitigations and safety cases; describe wet contact plans if feasible.
• Cover AI elements with a realistic certification pathway and explain assurance, verification and validation strategies for safety-critical autonomy.
• Map interoperability and standardisation pathways, including ATP 3.3.4.10 and a clear standardisation outline proposal for A4R.
• Detail data links and telemetry requirements including contested-spectrum and EMCON scenarios.
• Include a clear security-by-design approach and demonstrate compliance with PSI and classified information handling if applicable.
• Use the Ownership Control Declaration/Guarantee early if any entity has non-EU ownership/control; obtain national approvals in good time.
• For actual indirect costs, coordinate with national pricing authorities well ahead of submission; otherwise consider the 25% flat-rate.
• Ensure facilities have or can obtain necessary facility security clearances; list all assets and locations comprehensively.
• Demonstrate strong cross-border industrial cooperation, SME roles and robust supply chain security within EU/NO.

Summary

This EDF Research Action funds collaborative cross-border projects that will design, study and integrate technologies enabling autonomous and automatic air-to-air refuelling, a mission-critical capability for future airpower including unmanned aircraft. The topic focuses on high-fidelity relative navigation with robust sensor fusion, enhanced optical sensing and image processing, advanced flight control and supervision interfaces, interoperable data links and standardisation. Proposals must produce an A4R Concept of Operations, a standardisation outline, and demonstrate technologies through lab, simulation, sub-scale and flight testing, including a dry-contact demonstration and ideally a wet-contact trial, achieving up to TRL 6. The funding rate is 100% of eligible costs under a budget-based actual cost grant, with equipment reimbursed by depreciation only. Multi-beneficiary consortia from EU Member States and Norway are required, with strict eligibility and security provisions on ownership and control and on handling of classified or sensitive information. The indicative topic budget is €20 million with several projects expected to be funded. Applications are single-stage via the EU Funding & Tenders Portal and must follow the EDF call document, Model Grant Agreement and security instructions. Successful projects will reduce crew workload, increase safety and efficiency of refuelling, and enable manned-unmanned teaming while advancing EU strategic autonomy and interoperability.

Autonomous and Automatic Air-to-Air Refuelling (EDF-2026-RA-AIR-A4R)

This call under the European Defence Fund (EDF) Research Actions programme seeks proposals to develop sensor systems, hardware, sensor fusion, optical sensors, image processing, flight control algorithms and pilot assistance interfaces for autonomous air-to-air refuelling (A4R). The focus is on enabling accurate relative navigation between tanker, receiver and refuelling systems in adverse conditions, reducing crew workload and supporting manned-unmanned teaming.

Objectives and Scope

The general objective is to enhance endurance and efficiency of military aerial operations through automated refuelling, crucial for future manned and unmanned aircraft. Specific objectives include exploring sensor technologies up to TRL 6 for relative navigation, docking and refuelling processes. Proposals must address receiver autopilot functions, sensor integration, A4R concept of operations (CONOPS), standardisation outlines and flight test demonstrations including dry contact.

Targeted Activities

• Integrating knowledge (mandatory)
• Studies (mandatory): sensor integration, optical systems, standardisation, roadmaps, challenges
• Design (mandatory): flight control modes, crew interfaces, mission management systems, test environments
• Generating knowledge (optional)

Proposals must exclude boom technology and synergise with prior activities like EDF-2021-AIR-D-CAC on collaborative air combat interoperability.

Eligibility and Who Can Apply

Multi-beneficiary applications are mandatory with at least three independent legal entities from three EDF eligible countries (EU Member States or Norway). Beneficiaries must be established in eligible countries with executive management there. Non-EU entities may participate under strict conditions ensuring no control by non-associated third countries without approved guarantees. SMEs and mid-caps are encouraged.

Eligible Countries:EU Member States and Norway. Details in section 6 of the call document.

Consortium Requirements

• Minimum three beneficiaries from three eligible countries
• Coordinator from eligible country
• Associated partners allowed but cannot lead work packages

Funding Details

Indicative Budget:€20 million for this topic under EDF-2026-RA call. Several proposals may be funded.

Funding Rate:100% of eligible costs for Research Actions (EDF-RA).

Equipment costs: depreciation only. FSTP allowed within set ceiling. Detailed budget table required.

Timeline and Deadlines

Evaluation timeline in section 4 of call document. Grant agreement preparation follows.

Application Process

1. 1Register in EU Funding & Tenders Portal
2. 2Prepare proposal: Part A (administrative), Part B (technical, page limits per call document)
3. 3Submit via Portal as password-protected ZIP (AES-256 encryption)
4. 4Include annexes: Detailed budget table, participant information, ownership control declarations, etc.
5. 5Evaluation: Award criteria in section 9 (excellence, impact, implementation)

Admissibility: Page limits and layout per section 5. Full details in call document and Online Manual.

Key Requirements and Conditions

Functional Requirements

• Automatic/autonomous modes
• Teaming manned/unmanned aircraft
• Operate within receiver flight envelope
• Compatible with existing systems
• Interoperable with standards (e.g. ATP 3.3.4.10)
• Day/night, adverse weather operations
• Safe monitoring features

Security and Ethics

Proposals may involve sensitive/classified information. Comply with EDF Programme Security Instruction (PSI). Ethics self-assessment required. Ownership control declarations mandatory.

Evaluation Criteria

Thresholds and full details in section 9 of call document.

Expected Impact

• Improved reliability/safety of refuelling
• Faster/more efficient operations
• Enhanced standardisation/interoperability
• Reduced crew workload
• Lower mission cancellation rates
• Manned-unmanned teaming
• Reduced strategic dependencies

Contributes to STEP objectives in defence technologies.

Key Documents and Resources

Primary source: EU Funding Portal. Call document, templates, MGA available there. EDF Regulation 2021/697, Work Programme 2026.

Support: National Focal Points, IT Helpdesk, Online Manual. Partner search available on Portal.

Footnotes

1. 1All details subject to official call document. Verify latest information on Funding & Tenders Portal.