Hi everyone,
As discussed in our recent meetings and per AIP-006, I would like to formally open the discussion for a new heavy-lift initiative: Project Caribou.
Project Caribou is a heavy-lift hexacopter with a max take-off weight of around 200kg, designed specifically for heavy cargo and agriculture. It will take the best lessons learned from Project Feather and Project Quiver and use them to create a drone that will bring us back into the heavy-lift area. It’s the best way to build the operational experience we need for future larger aircraft, without the immediate risks of a manned eVTOL.
I would love to hear your thoughts on the following initial project proposal and requirements.
Project Proposal Draft
1. Project Summary Project Caribou is a heavy-lift hexacopter initiative. The goal is to develop a platform capable of lifting around 100kg. To achieve this cost-effectively, Caribou will focus on a mixed Steel, Aluminum, CF frame. Based on recent feedback, we will also explore scalable electronic architectures and frames that utilize less welding (e.g., CF tubes with 3D printed aluminum or stainless steel connectors). This makes the drone rugged, easily repairable in the field, and accessible to manufacture. The main operating fields will be Heavy Cargo Logistics (~100kg payload capacity) and Precision Agriculture (High-volume spraying).
2. Regulatory Strategy & Certification Designing a 200kg+ MTOW aircraft places us in the “Specific Category” (EU) or requires heavy exemptions (US). Scope Limitation: This project lays the technical groundwork for flight permits on an individual basis. We are NOT pursuing a general “Type Certificate” in this phase, as the requirements for daily commercial operations vary significantly between regions:
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EU (EASA): Requires SORA (Specific Operations Risk Assessment) and LUC (Light UAS Operator Certificate) for scale.
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US (FAA): Requires Section 44807 Exemption and Part 137 for Agriculture.
Full commercial certification will only be assessed in a future project phase once specific partners are secured.
3.1. Phase 1: Proof of Concept & Electronics Integration
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Objective: Validate the structural integrity of the core frame and the power architecture. Focus on developing the electronic system and integrating it into an existing test frame.
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Test frame: Steel tube inner structure with aluminum motor beams. Beams will be detachable (see Design Reference).
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Design Studies: Alongside the test drone, create CAD studies for scalable frames that require less welding, utilizing CF tubes and 3D printed aluminum/stainless steel connectors.
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Milestone: Successful construction, power-on tests, and a stable tethered hover flight demonstrating the power architecture’s ability to handle the target loads. Phase 1 ends with a general test of the electronic system and a successful flight with the test drone.
3.2. Phase 2: Scalable Design Overhaul
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Objective: Transform the test frame into a deployable prototype. This phase kicks off with a DAO review of the new scalable frame concepts to reach a consensus on the best structural path forward, as well as exploring specific business targets for the prototypes (e.g., cargo, winch operations, agricultural dispensing, or firefighting).
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Tasks: Based on the DAO consensus, we will easily scale the system and potentially build two frames in parallel (e.g., 50kg and 100kg payload variants). The construction of a second prototype in the USA will be pursued (e.g. for Javelina) to gather more flight hours and obtain feedback on manufacturing.
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Design Improvements: Implementation of foldable motor beams, optimized battery placement, and electronics improvements.
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Payload Integration: Development of payload bay prototypes for cargo and liquids or other spcific use cases.
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Milestone: Successful tethered hover flights carrying and operating:
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Liquid Config: Incremental load testing (40 / 60 / 80 Liters of water).
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Cargo Config: Demonstration of loading/unloading mechanics with multiple packages (e.g., 8 packages of 10kg each).
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3.3. Phase 3: Field Readiness
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Objective: Refine the user experience and conduct initial real-world mission simulations.
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Tasks:
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Minor structural improvements for weight reduction.
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User-experience upgrades regarding the payload operation.
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Milestone: Production of 2 “Beta” units for testing with partners in real-world scenarios.
3.4. Phase 4: Documentation
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Objective: Finalize technical documentation to ensure a seamless transition to the next project steps (e.g., certification or commercialization).
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Tasks:
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Create documents for flight logs and stress-test data.
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Finalize Bill of Materials (BOM), assembly guides, operating manual.
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Milestone: Publication of the full Caribou Engineering Report.
4. Project Timeline
Target official project start date: April 1, 2026.
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Phase 1: Proof of Concept (Months 1-4)
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Phase 2: Design Overhaul (Months 5-10)
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Phase 3: Field Readiness (Months 11-16)
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Phase 4: Documentation (Month 17-18)
5. Budget Cap Project Caribou operates in the heavy-industrial sector, requiring larger motors and high-capacity batteries.
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Labor Costs: $25,000/month
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Hardware Costs: $5,000/month
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Total Monthly Cap: $30,000/month.
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Note: Unspent funds do not roll over.
A multisig wallet will be established after approval to receive funds. The seats on the multisig will be; Project Lead (Julius) and GBC.
6. Governance Project Charter: A GitHub repository will be established upon approval to host the project data. AIP-007 Amendment: Upon approval, Project Caribou will be added to AIP-007 as an ACTIVE project. After each project phase a public vote will take place to proceed to the next phase. These votes will also offer the opportunity to adjust the budget, timeline or deliverables.
7. Project Lead I, Julius, will serve as the Project Lead. My responsibilities include architectural decisions, safety protocols for heavy-lift operations, and managing the development team.
8. Project Team I, Julius, will assemble the project team under the approved project budget.
9. Deliverables
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Prototype UAVs: Development and refinement of UAV prototypes through each project phase.
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Engineering Reports: Prepared for each major milestone, clearly outlining technical specifications, decisions, and current project status.
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Design Files: CAD models, PCB layouts, and software repositories accessible for community collaboration.
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User Guide / Flight Manual: Comprehensive manuals detailing UAV operation, maintenance, and troubleshooting.
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Manufacturing Guides: Up-to-date instructions & bill of materials enabling community-built prototypes.
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Meeting Summaries: Documentation of meeting attendance, key decisions, and action items recorded and shared via GitHub.
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Structured Documentation: Documents assigned unique identifiers for transparency, consistency, and version control.
Project Caribou: Technical Requirements & Objectives
1. Abstract & Mission Profile
Project Caribou aims to develop a heavy-lift hexacopter capable of high-capacity aerial logistics. Unlike lightweight composite drones, Caribou serves as an industrial drone prioritizing ruggedness and cost-effectiveness over absolute weight savings.
- Primary Mission: Heavy Cargo Transport & Precision Agriculture (Spraying).
- Target MTOW: Approximately 200 kg.
- Target Payload: 100 kg (useful load including payload mechanism).
- Design Philosophy: Hybrid material construction (Steel/Aluminum/CF), leaning toward less welding and more CF tubes with 3D printed aluminum/stainless steel connectors.
2. Structural Integrity
- 2.1 Hybrid Airframe: The central fuselage core SHALL be constructed from metal or composite tubing. It can be welded, screwed or glued. This provides a rigid backbone for the heavy payload and landing gear.
- 2.2 Modular Arms: The six motor arms SHALL be constructed from aluminum or CF tubing to reduce swing weight while maintaining strength.
- Phase 1 Config: Arms MUST be detachable via secure screw interfaces for transport.
- Phase 2 Config: Arms MUST feature a robust folding mechanism to allow the aircraft to fit a standard commercial van or car trailer without disassembly.
- 2.3 Landing Gear: The landing gear MUST be capable of absorbing hard landings at full MTOW.
3. Propulsion & Power Architecture
- 3.1 Configuration: The aircraft SHALL utilize a Hexacopter (6-rotor) configuration. This offers the best balance between redundancy, power and simplicity.
- 3.2 Thrust Margins: The propulsion system SHALL generate sufficient thrust to hover at 50-60% throttle with a full 100kg payload.
- 3.3 High-Voltage System: The power architecture SHALL operate at around 60-100V (18-24S) to include most off-the-shelf solutions for motor/inverter combinations.
- 3.4 Safety Disconnects:
- A physical, exterior-mounted High-Voltage disconnect (Kill Switch) MUST be accessible.
- A remote electronic circuit breaker/switch MUST be integrated for emergency shutdown.
4. Payload Capabilities
- 4.1 Universal Bay: The airframe MUST feature a Payload Bay that can be adjusted for missions.
- 4.2 Liquid Configuration: The bay SHALL accommodate a tank with a capacity of up to 80 Liters, including mounting points for pumps and spray booms.
- 4.3 Cargo Configuration: The bay SHALL accommodate a secure cage or latch mechanism capable of holding standard logistics packages (e.g., 8x 10kg boxes).
5. Avionics & Control
- 5.1 Flight Controller: The aircraft SHALL utilize an industry-standard, open-source ecosystem (e.g., Cube/Pixhawk series running ArduPilot).
- 5.2 Telemetry: A long-range telemetry link (>5km) is REQUIRED.
- 5.3 Redundancy: Critical sensors (IMU, GPS, Compass) MUST be redundant (Triple-redundant preferred).
- 5.4 Vision Feedback: The drone MUST incorporate a camera system for visual feedback to the operator.
I will adjust this post with updates over time.
Update 1 (05.03.2026):
- Added the possibility to scale the frame and power system (to 50kg payload for example).
- Added a possible prototype build in phase 2 in the US.
- Added the target project start date: April 1, 2026.
Concept presentation
