Key Note
Presentation(Korea)

2023. 02.10 (Friday)

Choi, Keeyoung(Prof. @ Inha Univ. , Former President of KSAS VTOL Chapter)Contents

1.Overview
2.Universities
3.Industries
4.Institutes
5.Conclusion

1/28

I. Overview

Overview Korea Government have launched several national programin last 5 years.
– In civil field : eVTOL Aircraft System Technology Development,
unmanned eVTOL for AAM– In military field : Light Armed Helicopter, Marine Attack
Helicopter, Unmanned VTOL for Observation and Delivery
Service Industry, Institute and University have worked together toreach the national R&D target for the future market
according to each capability– Industry : System Integration and Hardware Development– Institute : Core Technologies Research & Development– University : Basic Technologies Research & Development

 Next Slides shows the each activities of University, Industryand Institutes related to VTOL Technologies

II. Universities

Seoul National University
Aerospace Vehicle Design Laboratory
Prof. Kwanjung Yee | Ph. D. Candidate : 21 | Master Course : 9Ongoing researches for VTOL (1/2) – Conceptual Design
RISPECT+ (Rotorcraft Initial Sizing and Performance Estimation Code and Toolkit+)
Rotorcraft sizing, aerodynamic & acoustic performance estimation, fuel cell/battery sizing

CLOUDS (Conceptual Layout Optimization for Universal Drone Systems)
Mission-oriented performance assessment, design optimization

MADAM(Multidisciplinary Analysis and Design for Advanced Mobilty)
UAM Cost & Demand Estimation Analysis

Seoul National University
Aerospace Vehicle Design Laboratory
Prof. Kwanjung Yee | Ph. D. Candidate : 21 | Master Course : 9Ongoing researches for VTOL (2/2) – Detailed Design
Rotorcraft Aerodynamics and Aeroacoustics

Aircraft Icing Accretion

with high-order accurate scheme for vorticity conservation

ICEPAC (Ice Contour Evaluation and Performance Analysis Code)

Improved prediction accuracy using transition model

Single rotor in BVI condition

Prediction of Rotorcraft Icing Accretion
Coaxial, co-rotating rotor

Coaxial, counter-rotating rotor

Seoul National University
Structural design

Active blade aerodynamics

Multi-body dynamics analysis

NController design

Blade fabrication and test

CFD-CSD rotor higher harmonic control

Rotor test and analysis

Seoul National University
Step 1
Group
Research on the Data-based
1

conceptual design
techniques

MissionprofileGroup2

UAM configuration
DesignGroup 1-3
sharingGroup3

High precision UAM
flow/structure/noise analysis
and crash analysis

Detailed
designFinal deliverables

3D data sharing platformbased shape optimization
UAM multi-disciplinary
integrated concept
Battery life
design software
Improvement

Digital twin UAM
simulation

circuit

Robust autonomy systemdesign automation andverification

Prototype
test

Step 2

Initial deliverables

ATM/UTM coupled
automated flight technology

1st Technology
demonstration 1/5
scaled prototype

Mixedreality
operation
simulation
Noise/vibration reducing
design optimization

2nd Technology
demonstration 1/5
scaled prototype

Konkuk University
HETLAS : Component-Model based Helicopter Trim,
Linearization, and Simulation Program

Autonomous Rotorcraft Flight Control for Offensive
and Defensive Tactical Missions

Spline-RRT*-smart Algorithm on 3D Map

Autonomous Emergency Landing Flight Control
Reachable Path Planning toSafe landing Area

Adaptive Robust Nonlinear Rotorcraft Flight Control
Accurate tracking performance Nonlinear SMS/BSC DesignRobustness
 Incremental dynamics
 Immersion & Invariance (I&I)
 Tuning Function Method Variable Directional Forgetting
LS Estimator
Guaranteed Stability/Performance Lyapunov-Function Based Design

Konkuk University
HCUR: Fugelage Drag Prediction

Rotorcraft CFD Development▲ Wind tunnel experiments for HCUR scaled model▲ Dynamic stall prediction by using RBF-based grid deformation▲ CFD analysis & drag coefficient of each part with A.o.A.

Farfield Noise Prediction: Adaptive Chimera Grid
▲ LCH 5-bladed rotor in forward flight (left) & thrust in hover▲ Tip vortex-fuselage interaction

Konkuk University
Blade Design Optimization Framework

4th Generation M&S Program Development

 Develop blades while
collaborating with KARI, KAI

Int. Consortium Project: STAR (Smart Twisting Active Rotor)
NRF-BRL: Mars Atmospheric Flying Robot Laboratory

Pusan National University
Professor : Donghun Park & Sejong Oh (Emeritus prof.) Applied Aerodynamics and Design Lab. (AADL)- Development of practical & efficient aerodynamic analysis tools (ADM / ASM / Panel)- Implementation of aerodynamic tools for MDO framework
MDO Framework Implementation- Multi-fidelity based aero DB construction and design optimization
Actuator Disk/Surface Methods
CFD<Single>ADM<Tandem>

ASM<Coaxial><QTP><OPPAV>

Aerodynamic Analysis
Practical/Efficient
Aerodynamic Analysis Tools<LCH><UCCR>

Aero DB Construction & Design Optimization

Panel Method + Actuator Disk Theory

Pusan National University
Assistant professor : Yong Su Jung Computational Aerodynamics and Rotorcraft Lab (CARL) CFD Trained Invertible Neural Networks and Machine Learning for Rotor Blade Airfoil
Design (2022~2024]- Development of forward and inverse machine learning models that are trained using RANS simulations

 Line-based Unstructured Grid CFD Techniques for Rotorcraft Applications- Automated mesh refinement capability for 2-D Hamiltonian solver [2022~2024]- Improvements on a laminar-turbulent boundary layer transition model Interactional Aerodynamic/Aeroacoustics for Advanced Rotorcraft Configurations- Coaxial rotor hub flow simulations using hybrid RANS-LES- Aeroacoustic simulations for a wingtip-mounted propeller
Streamwise velocity

In-plane velocity

Chungnam National University
Professor Jae-Sang Park•

Ph.D from School of Mechanical and Aerospace Eng., Seoul National University, 2006•

Professor in Dept. of Aerospace Eng., Chungnam National University, 2013 ~ Present•

Research interests : Rotor aeromechanics analyses, Active vibration controls,
Conceptual design▪ Rotor aeromechanics analyses•

Rotorcraft comprehensive analysis tools : CAMRAD II and DYMORE II•

Conventional helicopters, Lift-offset compound helicopters, Tiltrotor aircraft
Lift at 87% span

400

2000

300

1600

200

1200

100

8000400-100-200

Present- single wake panel
Present- multiple wake panels
Flight Test- C9812

UH-60A rotor
090180Azimuth angle

270

[deg]

360

Flight test - Rotor
Flight test - Propeller
Flight test - Rotor + Propeller
Flight test - Engine
Present - Rotor
Present - Propeller
Present - Rotor + Propeller

X2 Technology Demonstrator

0-400

050

100

150

Airspeed (knots)

200250

X2TD Lift-offset
coaxial rotor

Chungnam National University▪ Rotorcraft active vibration controls•Active rotor vibration controls using Individual Blade pitch Control (IBC) or Higher Harmonic pitch Control (HHC)•

Active airframe vibration controls using Active Vibration Control System (AVCS)

Active vibration control for X2TD rotor
using Individual Blade pitch Control

Active vibration control system (AVCS) for smallscaled compound helicopter model

Active vibration control for medium utility
helicopter using Higher Harmonic pitch Control

Stacked rotor▪ Tiltrotor and eVTOL stacked rotor
UBER eCRM-001•

Whirl-flutter analyses for tiltrotor aircraft in airplane mode•

Hover performance analyses for stacked rotor of eVTOL aircraft

11Whirl-flutter analysis

1012
CAMRAD II (Present)
TEST[4]
RCAS with VVPM[4]Total rotor

9876

TiltRotor Aeroelastic Stability Testbad(TRAST, US)

5Axial Spacing ( Z/R) = 5.27%-80 -60 -40 -20

020

Index angle (deg),

406080Inha University
Vision-Based Automatic Landing System for UAM Considering Building Wind

Autonomous System with Cognitive Architecture

GIST (Gwangju Institute of Science and Technology)
Dynamic Stall Control

Multi-Copter Aerodynamics■ Dynamic stall control with impulsive jets
■ Impulsive jet‒ Sonic jet for 1 msec
‒ Generated from combustion-powered actuation‒ Breaking DSV into smaller vortices■ Control benefits■ Full Navier-Stokes Solver with overset grid
‒ OpenFOAM with SA-RC RANS
‒ CFD is validated for a hovering quadcopter■ VRS : vortex-ring state‒ Must-to-avoid condition in descending‒ Well captured in current CFD‒ Moment peak (negative) reduction by 70%‒ Lift enhancement by 20%
Dynamic Stall in
Retreating Blades
Overset grid
▲ Quadcopter in Hover𝑽𝒕𝒊𝒑 = 𝟔𝟑 m/s

𝑽𝒛 /𝑽𝒕𝒊𝒑

VerticalDescending(𝑽𝒄 /𝒗𝒉 = −𝟏)

0.2
0-0.4

Vortex-ring▲ Quadcopter in VRS (vortex-ring state)
Descending velocity 𝑽𝒄 = −𝟓. 𝟓 m/s = −𝟎. 𝟎𝟗 𝑽𝒕𝒊𝒑

[Kim, T. and Jee, S., 2023, Comp & Fluids][Park, Y. M. and Jee, S., 2023, AIAA Aviation]

theory.gist.ac.kr

GIST (Gwangju Institute of Science and Technology)
Multi-UAV Control

Collision Avoidance Control▲ Multi-UAV Control with UWB NO GPS for tagged UAV
 Positioning through RF-based UWB(ultra-wide band) with autonomous
anchored UAVs
 Decentralized position control withstable inter-vehicle communication
dcas.gist.ac.kr
Distributed Control and Autonomous System Labbiorobotics.gist.ac.kr

Gyeongsang National University (1 / 2)
 Biography
 Hakjin Lee, Ph.D. (hlee@gnu.ac.kr)•Assistant Professor, School of Mechanical and Aerospace Engineering, Gyeongsang National University•

Director, Rotorcraft Aerodynamics and Noise Simulation (RANS) Lab.

 Education•

Ph.D. in Aerospace Engineering, Korea Advanced Institute of Science and Technology (KAIST), 2019

•M.S. in Aerospace Engineering, Korea Advanced Institute of Science and Technology (KAIST), 2014

•B.S. in Aerospace Engineering, Korea Aerospace University, 2012

 Research Interests•

Rotor Aerodynamic, Aeroacousitcs•

Computational Fluid Dynamics (CFD), Computational Aeroacoustics (CAA), Vortex Methods•

Rotorcraft, Helicopter, Urban Air Mobility (UAM), Drone, Wind Turbine

 Research topic I Aeroacoustic analysis of urban air mobility•

Investigate the interactional aerodynamics and aeroacoustics of UAM•

Simulate the co-axial multi-rotor eVTOL vehicle in ground effects

Comparison of Isolated rotor and rotor-conical airframe

Acoustic dilatation field of co-axial eVTOL

Gyeongsang National University (2 / 2)
 Research topic II
 Comprehensive analysis of rotorcraft•Hybrid Lagrangian-Eulerian approach for simulating the complex rotorcraft•Provide an efficient and accurate aerodynamic analysis solution, which supports the aeroacoustic design of rotorcraft

Fundamental formulation and validation results of NVLM/VPM/CFD simulation

NVLM/VPM/CFD simulation of complete rotorcraft Research topic III
 Flow physics and aeroacoustics of iced airfoil and rotor blade•(a)Analyze the expanding process of separation bubble and noise generation of an iced airfoil

Re-attachment and turbulent separation bubble(b)Fully Separation
Turbulence wake fromIce accretionReattachment

Recirculation

Separation
Strongvorticity
Vorticityfrom TE

Instantaneous x-velocity contour and 𝝀2 iso-surface: (a) 6 deg. (b) 8 deg.

Vorticityfrom TEAcoustic dilatation field of iced airfoil

Hanseo University• Research Area: Aerodynamics


Development of a mid-fidelity aerodynamic
solver based on vortex methods
High-fidelity CFD computation for rotorcrafts

CFD computation for a tandem UAM helicopter• Research Area: Aeroacoustics

Development of a noise-prediction code forrotorcrafts (tonal/broadband/body-scattering)
Development of a community noiseassessment code

Rotor noise prediction for a 3-bladed UAV rotor

Hanseo University• Research Area: Design Optimization

Development of machine-/deep-learning
based surrogate models
Aleatory/epistemic uncertainty quantification
based on Bayes’ theorem

Design optimization of a sUAS rotor• Research Area: System Design

SketchCAD modeling

Conceptual
designPerformance
evaluation

Manufacture

Flight test

Data modelling of aircraft performances forconceptual designs
Conceptual design of aircrafts
Manufacture and flight test of designed aircrafts
Multi-Fidelity
Data Modeling

Data modelling for small-scale UAM vehicles

High-Fi.
Low-Fi.

Failed :(Design, manufacture, and flight test of a tilt-rotor UAM vehicle

Jeonbuk National University
 Development of Vibration Source Active Control Device SW forMedium Helicopter Vibration Reduction (2022~2024)- Nonlinear beam analysis coupled with aerodynamic model- Load analysis and verification with CAMRAD II Development of rigid coaxial rotor system design/manufacturing
technology (2022~2026)- High-precision rotor structural dynamics via 3D FEM and coupling withaerodynamic modelTorsionFlap<Verification of beam analysis with CAMRAD IIfor HHC application><Aeromechanical load/vibration analysis forcoaxial rotor system>

III. Industries

Korea Aerospace Industries

Korea Aerospace Industries

Korean Air
 Program Overview- KAL R&D program (Model Name : KUS-VS)- 2021. 1 ~ 2023. 8 (32 months)

 KUS-VS Characteristics

Target Gross Weight000 kg

Target Payload

00 kg

Overall Length4m

Prop Radius

1.5 m

Endurance

0 hrs

Max Speed

190 km/h- VTOL UAV for military propose- Electric & ICE Hybrid propulsion system- Long Range EO/IR/LRF Camera payload- Rapid deploy and ground transportation- STANAG 4586 Interoperability- Military Airworthiness Ready Program Milestone- '21.1Q : Scale model flight- '21.2Q : Electric proplusion system test
- '22.4Q : New OML release- '23.3Q : Design complete

Korean Air
 Program Overview- Government R&D program(Model Name : KUS-VM)- 2023. 8 ~ 2028. 7 (60 months)

 KUS-VM Characteristics

Gross Weight000 kg

Payload00 kg

Overall Length

6.4 m

Main Rotor Diameter

7.2 m

Max Endurance

0 hrs

Cruise Speed

100 km/h- VTOL UAV for Navy and Marine Corps- Long Range EO/IR and SAR/ISAR payload- Autonomous take-off and landing on
Destroyer class ship
- Military Airworthiness Ready Program Milestone- '23.3Q : Program start- '24.4Q : CDR- '25.4Q : Aircraft Roll out- '28.2Q : System development Complete

LIG Nex1
Overview

Appearance

Development of MTOW 200kg Multi-purpose Unmanned
Helicopter(Cargo/ISR)
ProgramType

Civil-MilitaryTechnology
Development

Period’17.12 ~ ’21.11

Prime Company

Sung-woo Eng.

Budget13,000,000 USD

Contractor

ADD ICMTC(Institute of Civil Military Technology Cooperation)

Progress’17.12 : Agreement and Program Start’18.04 : SRR (System Requirement Review)’18.11 : PDR (Preliminary Design Review)‘19.02 : CDR (Critical Design Review)’19.10 : TRR#1 (Test Readiness Review)‘20.02 : FFRR (First Flight Readiness Review)’20.06 : TRR#2 (Test Readiness Review)’21.11 : The program ends

Features
MTOW : 200kg+ (Payload : Max. 60kg)
Max. Speed : 150km/h+
Operational Altitude : 3km+Endurance(Payload) : 6hrs(25kg) / 3hrs(60kg)
Operational Range : 50km+
Payload : EO/IRLIG Nex1
Overview

Appearance* Localization
Development

Development of a Army Small UAV System for
Reconnaissance and Attack
ProgramTypeRapid
Demonstration
Acquisition
ProjectPeriod’20.12 ~ ’22.09

PrimeCompany

LIGNex1

Budget3,900,000 USD

Contractor**

DAPA(Defense Acquisition Program Administration)
Ground Control System*’21.11 : Delivery Completed(ROKA, 18ea)‘22.09 : ROKA Demonstration Support Report Submitted*

EO/IR/LRF*

MotorsIntegrated
FlightComputer**

Datalink

WarheadFeatures

Progress’20.12 : Contract

Image
Processing
Unit

Loitering munition for BN reconnaissance & attack missions
Operational Range : 8km+, Altitude : 300m+, Time : 30min+
Flight Speed : 90km/h, Impact Speed : 140km/h
MTOW : 15.0kg
IPX3 waterproof, Anti Jamming, KCMVP Communication Security

LIG Nex1
Overview

Appearance

Hybrid Engine based Payload 40kg Multi-copter
Cargo Drone Development for Civil-Military dual use
ProgramType

Civil-Military
Dual-use
Technology
Development

Period’20.11 ~ ’23.11

PrimeCompany

LIGNex1

Budget4,600,000 USD

Contractor

ADD ICMTC(Institute of Civil Military TechnologyCooperation)

Progress

Features’20.11 : Commencement of the agreement

Maximum Payload Weight : 40kg+’20.12 : Kick-Off Meeting

Operational Range : 10km+’21.09 : PDR(Preliminary Design Review)Operational Time : 60min+’22.05 : CDR(Critical Design Review)Operational Altitude : 400m+’23.04 : TRR(Test Readiness Review)

Maximum Flight Speed : 50km/h+’23.06 : FFRR(First Flight Readiness Review)

Powertrain : Engine Battery Hybrid’23.10 : Final Evaluation’23.11 : The program ends

LIG Nex1
Overview

Appearance

Payload 200kg Cargo Drone Technology Development
based on Hydrogen Fuel Cells
Program
TypeNational R&D
Program(MOTIE)

Period

’21.06 ~ ’25.12

PrimeCompany

LIGNex1

Budget36,000,000 USD

Contractor

Korea Evaluation Instituteof Industrial Technology(KEIT)

Progress’21.06 : Agreement’21.07 : Kick Off Meeting‘21.10 : SRR/SFR(System Requirement/Functional Review)’22.11 : PDR(Preliminary Design Review)’23.09 : CDR(Critical Design Review)’23.12 : Mid-Term Evaluation’25.01 : FFRR(First Flight Readiness Review)’25.09 : Final Evaluation’25.12 : The program ends

Features
Maximum Payload Weight : 200kg+
Operational Range : 50km+
Operational Time : 1hrs+
Maximum Flight Speed : 100km/h+
Powertrain: “Hydrogen fuel + Battery” Hybrid

Hanwha Systems
 Overair Butterfly- Capacity: 1 pilot + 5 pax- Rotor system: 4 tilt rotors withindividual blade control (IBC) system- Full-scale propulsion system test
program completed in Fall 2022

 Advanced Research onHybrid-Electric VTOL Aircraft- Feasibility study on gas turbine hybridelectric VTOL aircraftHanwha Systems
 Flight Control System of
Optionally Piloted PAV (OPPAV)- OPPAV Flight Control System Dev.
Project (Apr. 2019 - Dec. 2023)- Work scope:

FLCC SW(OFP) Design and Implementation
OPPAV HILS Configuration Setup
FCS System Integration Test (HILS & RIG)OPPAV Ground/Flight Test

 eVTOL Aircraft Flight Simulator- UAM VIPP (Virtual Integrated OperationPlatform) Project (Apr. 2022 - Dec. 2025)- Work scope: Development of fixed-base and motionplatform flight training devices for threedifferent types of eVTOL aircrafts

Fixed-base
Flight Simulator

Motion-platform
Flight Simulator

Vectored Thrust

Lift-plus-Cruise

Multicopter

IV. Institutes

Korea Aerospace Research Institute

1.OPPAV
2.High-Speed Rotor System
3.30kW-H2 Fuel Cell Unmanned Helicopter
4.Low Noise Prop-Rotor for UAM eVTOL

1. OPPAV(Optionally Piloted Personal Air Vehicle) eVTOL Optionally piloted eVTOL technology demonstrator is being
developed (2019~2023)- One seater class. (Vc > 200kph, Range > 60km)- 8 electric motors, full electric using Li-Ion, 4 tilt props and 4 fixed lift props- Airworthiness standard draft is being developed in parallel- Wind tunnel testing is completed, the first flight is planned in Jan-2023<Wind Tunnel Test of OPPAV Scaled Powered Model in KARILSWT><KARI OPPAV Concept>

3737/28

2. Rotor System for High-Speed Forward Flight Rigid Coaxial Rotor System Development for High Speed Long
Range Utility Helicopter. 2022. 12. ~ 2026.12 (Defense Acquisition Program Administration). Airspeed > 000 knot, High efficiency (FM > 0.00, L/De > 00)- Design and analysis of low drag rigid coaxial rotor planform with lift offset- Rigid composite blade design and analysis- Efficient hub control system design and analysis- Small-scaled model design, analysis, fabrication and ground & wind tunnel test

Reference model3. 30kW-H2 Fuel Cell Unmanned Helicopter Net power 30kW class fuel cell power pack system for a unmanned
helicopter with 200kg class maximum takeoff weight (2021~2025)- Rotor type : 2 bladed-coaxial rotors with 2.18m of rotor radius- Rotor RPM : 580RPM- Weight : 250kg- Propulsion system : Electric motor powered by primary fuel cell and battery<Coaxial rotor with fuel cell><Mission profile and power sharing>3939/28

4. Low Noise Prop-Rotor for UAM eVTOL
 Low noise prop rotor (2020~2023)- Five bladed prop rotor with 1.3 meter of radius- Maximum thrust 500kgf per prop rotor for Five seater class UAM- Noise level 64dBA away from 150meter in forward flight- Figure of Merit 0.7 above<Analysis of noise level in forward flight and hover><Noise level measurement of prop rotor>

4040/28

V. Conclusion

V. Conclusion
 In Civil Side, eVTOL Aircraft System Technologies werefocused on AAM(UAM, RAM) Application– Passenger Drone, Parcel Delivery Service, etc– KARI, Hanwha Systems, Hyundai Motors, KAI, Vessel
Aerospace, etc.

 In Military Side(Manned) VTOL System Technologies have been
focused on Army’s Light Armed Helicopter and Marine
Attack Helicopter– LAH Helicopter Production Start(2023~ )– Marine Attack Helicopter Development Start (2022~)– KAI

 In Military Side(Unmanned) VTOL System Technologies havebeen focused on Army’s Observation and Scout, Delivery
Service– KAI, KAL, LIG Nex1,Hanwha Systems, Vessel Aerospace

Thank you!