1. Low Level RPAS Traffic Identification and Management
Milano, July 2017
Low Level RPAS Traffic Identification and Management
C. Le Tallec, P. Le Blaye

2. RPAS Traffic Management Motivations
Market opportunities and expected benefits of small RPAS operations below 500 feet AGL (VLL), in Visual Line of Sight & Beyond VLOS
© SNCF
Railway & powerline inspection
Aerial firefighting & SAR operations
Agriculture & parcel delivery
Potential exponential growth of RPAS low level flights in many types of location, in various classes of airspace

3. RPAS Traffic Management Motivations
The VLL airspace is also used by many manned aircraft…

4. SAFETY The LLRTM project A 3-year project to:
Develop and to demonstrate an integrated system for the management of RPAS operations below 500 feet in uncontrolled airspace (classes F-G) using a combination of solutions:
Airborne cooperative devices
Ground sensor to detect cooperative and non-cooperative traffic
Connection to existing networks on the Internet
Define CONOPS and design HMI for 2 human roles:
Remote Pilots (RP)
RPAS Traffic Manager(s) (RTM)
SAFETY
The role of the RTM would be to manage the RPAS traffic, ie: 1) watch the global traffic 2) alert the remote pilots of incoming manned traffic and 3) coordinate multi RPAS operations
Funding
Consortium 4 4

5. RPAS Traffic Identification motivations
Enforce compliance with existing flight regulations (no fly zones, max flight altitudes)
Defense of sensitive buildings and infrastructures
Deny illegal photography
Protect people gatherings
Protect civil security & safety emergency operations…
Nuclear power plant
Sensitives locations
Crowd protection

6. SECURITY The LLRTId extension
The LLRTM project has been extended (LLRTId ) to satisfy the legal requirements for mandatory RPAS identification
Use a combination of solutions similar to the LLRTM ones:
Airborne cooperative devices, but simplified to only report position and identification
Ground sensor to detect adequately equipped RPAs
Connection to existing surveillance networks on the Internet
Define CONOPS and design HMI for 2 human roles:
Sensitive area managers (Fixed stations for situation awareness)
Police officers (Mobile stations for surveillance and law enforcement)
SECURITY
The role of the RTM would be to manage the RPAS traffic, ie: 1) watch the global traffic 2) alert the remote pilots of incoming manned traffic and 3) coordinate multi RPAS operations
Funding
Consortium 6 6

7. Flight safety issues and potential solutions
Problem statement:
Remote pilots compliance with RoA without being on board is especially challenging (“See and avoid” )
Pilots of manned aircraft may not be able to see and avoid small RPAs (conspicuity issue)
Current consensus is that RPAs should remain clear of manned a/c (RWC) (e.g. French CAA 2015, Eurocontrol RPAS CONOPS 2017)
The following assumptions are also made:
- It is not acceptable to mandate any additional equipment to legacy users in order to accommodate RPAS at low altitude
- It is not acceptable to deny the use of the VLL airspace to legacy users

8. Flight safety issues and potential solutions
Potential technical solutions to RWC :
Equip small RPAs with an onboard Detect & Avoid system  
Airspace segregation: creation of corridors or layers for RPAS exclusive use 
Transfer the D&A function to the ground (GBDAA) by providing remotes pilot and RPAS traffic managers (RTM) with all traffic information to enable RPAs to remain well clear of all manned traffic
The following assumptions are also made:
- It is not acceptable to mandate any additional equipment to legacy users in order to accommodate RPAS at low altitude
- It is not acceptable to deny the use of the VLL airspace to legacy users

9. Flight security issues and potential solutions
Problem statement:
RPAS can be used illegally:
Voluntarily
By mistake or ignorance of flight restrictions
Law enforcement is not easy if the drone is not identified
Registration of any flying RPA is difficult to check
Lack of objective RPAS traffic information for security analysis (building a data base of RPAS flights, identification of “unusual” behavior…)
The following assumptions are also made:
- It is not acceptable to mandate any additional equipment to legacy users in order to accommodate RPAS at low altitude
- It is not acceptable to deny the use of the VLL airspace to legacy users

10. Flight safety issues and potential solutions
Potential technical solutions to the Id mandate :
Equip the small RPA with an onboard identification and tracking system
Makes the capability of this system extendable for D&A
Makes the overall system affordable thanks to mass production of the various sub-systems made with off-the-shelf components (both on board and on ground)   
The following assumptions are also made:
- It is not acceptable to mandate any additional equipment to legacy users in order to accommodate RPAS at low altitude
- It is not acceptable to deny the use of the VLL airspace to legacy users

11. Strategic level of the LLRTM CONOPS
RPAS vs manned A/C
RPA flights below 500 ft.
Mandatory flight declaration
Global traffic awareness using web services
RPAS vs RPAS => Strategic deconfliction
Semi-circular rule for vertical separation
Trajectory planning, possibly with 4D contracts

12. RPA/RPA conflict probability issue
Lower the probability of RPA/RPA head-on conflict
Semi-circular rule below 500ft for RPAs
Issues:
Flight altitude reference
Vertical navigation accuracy
500 ft AGL limit
Manned traffic safety buffer zone limit
East-bound (EB) flying zone
EB / WB 4D buffer zone
West-bound (WB) flying zone
Terrain safety buffer zone limit
50 ft
175 ft
50 ft
500 ft
175 ft
50 ft
Ground
Sea

13. Infrastructure manager
LLRTIM architecture
optional
Police officer
Infrastructure manager PO 13

14. Functional architecture and levels of automation
Low
High
Low
High
Low
High
Levels of automation

15. Candidate technologies for onboard identification devices
New needs, no legacy system
Cellular networks (GSM, GPRS..): coverage issues and technology not yet proven for aeronautical usage
Adapted FLARM (Flight Alarm):
Transmit the a/c identification and GPS position at regular time intervals under a coded radio protocol (868 MHz)
Over FLARMs already equip gliders, GA aircraft, some police and medical rotorcraft will receive the information
Not certified.. but designed by electronic industry standards and providing safety benefits as acknowledged by EASA and FAA
Existing network of ground receivers and web services (OGN)
NB: For commercial reasons, only PowerFLARM is approved for use in the US and Canada, using the a different frequency band ( MHz) .

16. Candidate technologies for onboard traffic awareness and collision avoidance devices
Needs for traffic awareness & collision avoidance between aircraft is not new, legacy systems already exist
Transponders 1090ES, ADS-B
TCAS
FLARM (Flight Alarm):
Complement the identification device with the functionalities of the conventional FLARM
Traffic awareness and alert devices based on a concept patented by ONERA in 1998, initially designed for glider pilots
Transmit and receive the a/c identification and GPS position at regular time intervals under a coded radio protocol (868 MHz)
‘PowerFLARM’ extended to receive ADS-B and transponders
Existing network of ground receivers and web services (OGN)
NB: For commercial reasons, only PowerFLARM is approved for use in the US and Canada, using the a different frequency band ( MHz) .

17. The existing network of ground receivers (OGN)

18. Available information on © OGN
Normal mode
Aircraft Id
Transmitter Id
Aircrat model (as stored in the OGN data base)
« Stealth » mode
Only position and aircraft type are shown

19. Global situation awareness and local RPAS traffic management: LLRTM
Global view
(Internet OGN)
Large coverage
Situation awareness
Local view
(LLRTM GS)
Accurate and real time
Assistance for RWC

20. Global situation awareness and local RPAS traffic surveilllance: LLRTId
Global view
(Internet OGN)
Large coverage
Large area surveillance
Local view
(LLRTId GS)
Accurate and real time
Assistance for law enforcement

21. LLRTM preliminary testing (07/2016)
One RPAS vs one intruder (VLA) in various encounter conditions
Focus on the detection range, signal acquisition and stability

22. LLRTId Demo flights for remote Id (03/2017)
Ident. and tracking of three drones at distances up to 1 km High gain antenna for extended range HMI improvements and adaptation
LLRTM presentation to JARUS, May 18, 2017

23. Planned tests of the LLRTM system
Support of the Remote Pilot for D&A
Involving tow planes on the airfield of Salon AFB
Focus on traffic alerting, timing and avoidance strategy
Support for BVLOS operations
Drone on the first commercial parcel delivery line (> 20 km distance)
Involving helicopter(s), VLA and drone intruders

24. Research questions Human roles and HSI
To which extent and how should the remote pilot (RP) be kept in the loop?
Separation & traffic avoidance: RP in the loop?
Collision avoidance: RP on the loop, then automated?
What should be the role of the RPAS traffic manager (RTM)? How and when should the RTM coordinate with the remote pilots? How many RPAS could be actually managed simultaneously?
What should be the requirements for HMI design, standardization, integration and validation?

25. Research questions Regulatory basis
What are the appropriate protection volumes and time thresholds not to scare the pilots of manned a/c? Should they depend on the type of RPA? on the type of operation?
What about transition between LLRTM and ATM?
Architecture, technologies, algorithms, software
What is the appropriate allocation of functions (air-ground and human-machine) to insure the required level of safety?
What are the sensors and equipment to be used on ground and onboard the RPA?
Which communication links and frequencies should be used?
Navigation at low altitude AGL (accuracy, terrain and obstacles),

26. Thank you for your attention
Conclusion
The increase of RPAS VLL operations requires efforts from the whole community to complement the regulation and to design systems to integrate these new users of the airspace, taking into account safety and security issues
LLRTIM (LLRTM & LLRTId) provides a solution for
for RPAS identification, based on proven technologies
for RPAS traffic management
Having a single system for both RPAS Id and RPAS traffic management functions:
Makes costs lower
Reduce the mass of the systems to be carried aboard the RPA
Thank you
for your attention