Mini-Bee

TRL4 demonstrator · Hybrid VTOL · Humanitarian aviation

Mini-Bee Hybrid VTOL

A collaborative hybrid VTOL multicopter concept designed for urgent humanitarian missions, light air ambulance operations, emergency logistics and rapid field deployment without runway dependency.

18

distributed rotors

450 km

target range

160 km/h

cruise speed

700 kg

MTOW target

Mini-Bee is a collaborative hybrid VTOL multicopter project coordinated by Technoplane SAS under the Lesser Open Bee License 1.3.

The current reference configuration is the Mini-Bee P2H18: a two-seat hybrid VTOL multicopter using 18 distributed rotors, a Rotax 916 iS thermal engine, twin EMRAX 208 high-voltage electric machines, supercapacitor support and computerized flight control.

Current maturity level: TRL4 – demonstrator stage.

Official links

• Mini-Bee website
• Collaborative Bee Wiki
• Lesser Open Bee License 1.3

Project Vision

Mini-Bee is not only a VTOL technology demonstrator. It is designed around a mission need: reaching people and equipment in difficult environments where conventional ground access is slow, damaged or unavailable.

Medical response

Rapid access for a pilot, doctor, operator or stabilized passenger in areas where ground routes are disrupted.

Field deployment

A modular logistics concept based on LD3 air cargo containers and controlled assembly near the mission area.

Lower complexity

A practical VTOL demonstrator intended to reduce deployment complexity compared with conventional helicopter logistics.

The project follows an open-innovation approach where academics, industrial partners, independent contributors and humanitarian stakeholders can contribute to the development of a practical VTOL platform.

Reference Configuration – Mini-Bee P2H18

Parameter	Current reference value
Aircraft type	Hybrid VTOL multicopter
Configuration	P2H18 – 2 persons on board, 18 rotors
Capacity	1 pilot + 1 passenger or medical operator
Propulsion	Rotax 916 iS + 2 × EMRAX 208 HV CC
Lift system	18 distributed vertical-lift rotors
Cruise speed	160 km/h target
Target range	450 km
Cruise power	100 kW target
MTOW	700 kg target
Safety approach	Rotor redundancy, ballistic parachute, emergency beacon, computerized flight control
Deployment	Modular packing into LD3 containers
Maturity	TRL4 – demonstrator stage

Visual Overview

The following visual library is prepared for the official Mini-Bee image set. The aircraft configuration must remain unchanged: white Mini-Bee fuselage, homogeneous hexagonal upper rotor structure, symmetrical metallic tubular arms, triangulated structure connected to the central hub, and exactly 18 rotors with 18 visible propellers.

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  Hero view – humanitarian VTOL concept

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  Reference product view – P2H18

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  Hybrid technical architecture

• 

  Light air ambulance mission

• 

  Disaster relief mission

• 

  Remote access mission

• 

  Emergency energy support

• 

  LD3 modular deployment

• 

  Cockpit, HMI and avionics

• 

  Tarmac assembly

Mission Logic First

The Mini-Bee project follows a mission-first design logic. The aim is not to reproduce an air taxi concept, but to study a practical aircraft for humanitarian and emergency operations.

The aircraft is intended for situations where:

• roads are damaged, slow or unavailable;
• a conventional helicopter is too costly or difficult to deploy;
• a runway is not available;
• rapid access is more important than high cruise speed;
• one pilot and one passenger/operator are sufficient;
• compact logistics and field assembly are essential.

Mission design principle

Reach the mission area first.

Mini-Bee prioritizes practical access, deployability and emergency usefulness over luxury mobility or high-speed transport.

Core Humanitarian Missions

Light Air Ambulance

Mini-Bee is primarily studied as a light air ambulance and medical response platform.

• transport of a doctor or medical operator;
• access to isolated clinics or mountain areas;
• evacuation of a stabilized patient;
• delivery of medical supplies to remote sites.

Disaster Relief

In disaster zones, the first operational difficulty is often access.

• rapid reconnaissance;
• delivery of urgent supplies;
• transport of a field operator;
• support after road or bridge damage.

Remote Access

Remote areas require aircraft that can operate without a runway.

• isolated medical sites;
• mountain rescue support;
• island-to-island emergency transport;
• temporary field operations.

Emergency Energy Support

The hybrid architecture is also studied for emergency power support.

• emergency electrical generation;
• crisis-site power support;
• mobile energy buffer using supercapacitors;
• support to temporary medical units.

Why Hybrid Propulsion Matters

A fully electric multicopter can be attractive for short missions, but humanitarian operations often face limited charging infrastructure, uncertain logistics and longer-distance access needs.

Mini-Bee therefore studies a hybrid architecture intended to combine the endurance and practicality of thermal energy with the controllability and redundancy of distributed electric lift.

Hybrid Technical Architecture

Fuel

Rotax 916 iS

EMRAX

Rectifiers

DC bus

ESCs

18 rotors

Subsystem	Role
Rotax 916 iS	Thermal power source for hybrid generation
EMRAX 208 HV CC	Electric machines used in the hybrid power chain
Rectifiers	Conversion toward high-voltage DC distribution
Supercapacitors	Buffer for transient power demands and emergency support
ESC / power controllers	Individual rotor control and thrust distribution
18 rotors	Distributed vertical lift and redundancy studies
FCU	Stabilization, flight control, degraded modes and safety logic

Flight Control Unit and Stabilization

Why a dedicated FCU is needed

Mini-Bee is neither a conventional helicopter nor a battery-only multicopter. The FCU must manage distributed lift, hybrid power behavior, assisted control and degraded modes.

• vertical take-off and landing;
• hover stabilization;
• pitch, roll and yaw control;
• power distribution across 18 rotors;
• STOP mode and emergency logic;
• telemetry and flight data recording.

Current prototyping direction

The current prototyping approach is based on STM32 / Nucleo components and inertial/environmental sensors.

• accelerometers and gyroscopes;
• magnetometer;
• barometric pressure sensor;
• GPS or positioning input;
• power and rotor monitoring.

Cockpit, HMI and Avionics

The cockpit concept is designed around simplified assisted flight control.

• one pilot on board;
• joystick-based control;
• sport / assisted mode logic;
• emergency beacon;
• Kanardia EMSIS / DAQu equipment studies;
• clear warning and alarm logic;
• computerized flight assistance.

Important status

The aircraft remains a demonstrator. The final cockpit configuration must be validated through HMI studies, simulation, ground tests and future certification-oriented reviews.

Modular Deployment with LD3 Containers

A major operational goal of Mini-Bee is rapid deployment through standard air cargo logistics.

Module	Content
LD3 – Cockpit	Main cabin, seats, avionics and central structure
LD3 – Tubes	Tubular frame, structural arms and assembly elements
LD3 – Blades / Rotors	Rotor elements, blades and mission equipment

Tarmac Assembly

1. Air transport by civil cargo aircraft.
2. Unloading of LD3 modules.
3. Controlled assembly on tarmac.
4. Ground checks.
5. Propulsion and FCU validation.
6. Mission preparation close to the intervention area.

Safety Philosophy

Distributed lift
18 rotors for redundancy studies and thrust allocation.

Emergency recovery
Ballistic parachute, emergency beacon and degraded modes.

Occupant protection
Anti-crash seats and structure as central design topics.

A single-engine hybrid multicopter does not follow the same safety logic as a conventional helicopter. For this reason, emergency descent, parachute recovery and rotor redundancy are central design topics.

Certification-Oriented Development

Mini-Bee is currently a TRL4 demonstrator. It is not presented as a certified operational aircraft.

The development approach anticipates certification logic by considering:

• CS-27 small rotorcraft logic;
• SC-VTOL capable aircraft considerations;
• hybrid propulsion compliance topics;
• electric and hybrid propulsion system references;
• EWIS and high-voltage power distribution;
• crashworthiness;
• flight control software and verification;
• requirement compliance matrices.

Collaborative Organization 2025–2026

The Mini-Bee project is collaborative by design. Academic and industrial partners contribute to specific work packages.

Work package	Main focus	2025–2026 orientation
FCU – 18 rotors	Stabilization, rotor allocation, STOP mode, degraded modes	ESTACA Saint-Quentin studies and STM-based prototyping
Hybrid power chain	Rotax / EMRAX / rectifier / supercapacitor modeling and tests	Centrale Lille studies and hybrid generation test bench
Structure and crashworthiness	Tubular structure, rotor support, crash resistance	ESTACA Bordeaux and Lycée Louis Armand studies
Avionics and HMI	Displays, joystick, warning logic, Kanardia integration	ESTACA SQY and Centrale Lille coordination
Certification framework	SC-VTOL, CS-27, compliance matrix, test logic	Progressive structuring toward pre-certification

Roadmap

Period	Target
2025–2026	Detailed design, FCU 18-rotor development, Rotax + Kanardia ground tests, hybrid generation tests
2026	Integrated ground demonstrator with propulsion, FCU and sensors
2027	Tethered flight prototype target
2028	First free-flight demonstrator target
2029	Pre-certification work and SC-VTOL / CS-27 compliance matrix

Project History

The Mini-Bee project was launched in 2015 to study lightweight personal air transportation and progressively shifted toward medical and humanitarian use cases.

Past project stages include:

• Minibee TRL1
• Minibee TRL2
• Minibee TRL3
• Minibee TRL4

Earlier presentations and public project milestones:

• File:20210414 Mini-Bee v10.pdf
• File:20210407 VTOL et Mini-Bee v2.pdf
• File:20230418 Mini-Bee v16.pdf
• File:20240417 Prez Mini Bee ECL.pdf
• File:20251012 Mini-Bee v24.pdf

The 2025 reference configuration updates the project around the P2H18 architecture with 18 distributed rotors, Rotax 916 iS hybrid power, two persons on board and LD3 deployment logic.

Relation with RED VTOL ONG

RED VTOL ONG gives the project a strong humanitarian orientation. The Mini-Bee aircraft concept is studied as a tool for missions where time, access and practical deployment are central.

• reach difficult areas faster;
• transport useful payloads or one additional person;
• support medical intervention;
• reduce dependency on runway infrastructure;
• remain more deployable than a conventional helicopter;
• provide a practical bridge between humanitarian constraints and VTOL technology.

See also:

• RED VTOL ONG

Current Limitations

 Mini-Bee is still in demonstrator stage.

• no certified operational aircraft yet;
• propulsion and FCU integration still under validation;
• structural design and crashworthiness studies still in progress;
• flight envelope not finalized;
• certification basis and means of compliance still under construction;
• mission use cases must remain demonstrator-level until validation.

Links

• Mini-Bee website
• Collaborative Bee Wiki
• Lesser Open Bee License 1.3
• EMRAX electric motors
• Rotax aircraft engines
• Kanardia avionics
• STM32 Nucleo boards

Summary

Mini-Bee is a TRL4 collaborative hybrid VTOL demonstrator designed around urgent humanitarian missions.

18 distributed rotors

Rotax 916 iS hybrid propulsion

EMRAX 208 electric machines

Supercapacitor support

Two persons on board

450 km target range

160 km/h cruise speed

LD3 modular deployment

The project continues toward an integrated ground demonstrator, tethered flight testing, free-flight demonstration and progressive pre-certification work.