A Complete Guide to Creating a BVLOS Concept of Operations (CONOPS) – Part 2

Dec 8, 2020

In this article, we’ll go over some of the basic frameworks and topics that you should cover in your CONOPS plan—but make sure to check out Part 1 first.

Aircraft and Technical Specifications

When the FAA reviews the CONOPS document, they will want a detailed overview of the proposed aircraft system to be used. Include a specification sheet of the aircraft, as well as any OEM-provided standard operating, maintenance, and emergency procedures for the aircraft. If one is unavailable, you can always check with Iris Automation to see if we have one created specifically for your chosen aircraft. 

Component Diagram

Given that there are multiple hardware and software components working together inside the aircraft, provide a component diagram that shows how each piece of equipment is connected and interacts with the other.

Collision Avoidance

Collision avoidance technology is an important component of a BVLOS operation. Iris Automation’s Casia system is an excellent example of collision avoidance technology that you should include and detail in the CONOPs. Detailed information about the technology can be found in the Casia Long Range System Outline and Test Methods document, as well as the Casia Quick Start Guide. Both of these documents are provided within the Safety Case documentation. 

The documentation covers the following:

  • When Casia should be used
  • The system’s architecture and functions
  • Technical specifications
  • Its compliance with detect-and-avoid standards currently in development
  • How the system is tested
  • Environments and conditions in which it has been tested for use
  • System limitations
  • System performance—including all test results from the system to date

Critical Component Descriptions

Include descriptions of the following equipment as part of the systems overview:

  • Radio & Ground Control Station (GCS) Configuration
  • ADS-B equipment onboard 
  • Datalink (including C2 and non-C2 datalink)
  • Autopilot and mission planning software
  • Reliability data around the aircraft being used

Additional Details

Any additional information that is relevant to the sUAS system being used should be included; these may include the following:

  • Design and production process of the aircraft (if the aircraft is custom-built)
  • Configuration management (Configuration Management policies and procedures in place for the proposed operations)
  • Maintenance procedures for the sUAS system
  • Any other additional equipment used to support operations. This could include a launch and recovery system, generators, power supplies, etc

Mission Specifications & Operational Volumes

Any good CONOPS documentation will have a detailed description of the mission to be conducted, the proposed operational area, and the risk mitigation processes in place. The operational area should include a map of the area, and proposed operational, contingency, emergency and ground risk buffers (SORA containment volume). 

Additionally, include details about the surrounding area (e.g. population centers, aerodromes, any airspace of note, etc), as well as your launch and recovery area. It’s also important to detail your operations over people (OOP) mitigation methodology that should include either ensuring people not involved with the flight operation do not enter the operations area or the kinetic energy of the UAS is reduced to such a level that any impact with an unsheltered human is non-lethal. 

Standard Operating Procedures and Limitations

Generally describe the following documentation, and reference where it is attached in the waiver submission packet:

 ● Standard Operating Procedures

 ● Flight Operations Manual

 ● Emergency Procedures

 ● Fleet Management System

 ● Maintenance Procedures

Risk assessment and mitigation

Operational Risks

This adage in aviation summarizes risk mitigation aptly: “Never let an airplane take you somewhere your brain didn’t get to five minutes earlier.” The governing principle behind risk assessment and mitigation is to determine all possible risks that may arise in a flight operation and to have measures in place to mitigate these risks. These should be laid out in the CONOPs, and include a description of the risk as it is presented in the operation, followed by methods by which this risk is being addressed or mitigated. Examples of risks include avionics failure, flight planning errors, RPIC errors, and so on. 

Intrinsic Ground Risk Class (GRC) and Mitigation

Intrinsic UAS ground risk relates to the risk of a person being struck by the UAS (in the case of loss of UAS control with a reasonable assumption of safety). A follow-up to this is the mitigation strategy to be used to prevent this (e.g. having a deployable parachute on the UAS, or by visually detecting and preventing ground intruders from entering the operational volume).

Air Risk Class (ARC) and Mitigation

Air Risk here refers to airspace collision risks as present in the airspace in which the UAS is operating. The competent authority, ANSP, or UTM/U-space service provider, may elect to directly map the airspace collision risks using airspace characterization studies. These maps would directly show the initial Air Risk Class (ARC) for a particular airspace. The ARC is a qualitative classification of the rate at which a UAS would encounter a manned aircraft in typical generalized civil airspace. The ARC is an initial assignment of the aggregated collision risk for the airspace, before mitigations are applied.

Strategic Mitigation

A description of strategic mitigation steps taken to address air risk classes should be detailed out. These include steps like using pre-flight checklists to reduce the likelihood of component failure mid-air, ensuring flight paths don’t interfere with manned aviation operations, etc. 

Tactical Mitigation 

Tactical mitigation refers to the usage of detect-and-avoid (DAA) technology on-board the UAS in the event of BVLOS operations, or using a visual observer in the case of VLOS operations. For any BVLOS operation, avoiding both ADS-B cooperative and non-cooperative intruders is paramount. If DAA is used, the system outline and testing methods document for the DAA system is provided within the Safety Case Documentation. 

Generalized Risk Mitigation

Additionally, the CONOPS should include strategies to reduce the overall risk of the operation by adopting general risk mitigation strategies, like the following:

  1. Operation restriction by boundary

2. Operation restriction by chronology, i.e. conducting operations during times of the day when traffic is demonstrated to be at the lowest density

3. Operation restriction by time exposure—this involves limiting the duration of transit of the UAS through high risk areas

4. Strategic mitigation by common flight rules—common CFR mitigation strategies include things like anti-collision lighting, filing flight plans, transponders, etc that enhance the overall safety of operations, similar to the use of a Notice to Airmen (NOTAM). 

5. Strategic mitigation by Common Airspace Structure—these can take a number of shapes from designated airspace corridors to Unmanned Traffic Management systems separating aircraft during takeoff or holding patterns

Final Air Risk Classification (ARC) and Final Ground Risk Classifications (GRC)

Using the JARUS SORA methodology, a final ARC and GRC is determined. This is based on the intrinsic ARC and GRC as determined by the operations, but incorporates the reductions from the mitigation strategies taken to arrive at the Final ARC and GRC. 

Specific Assurance Integrity Level (SAIL)

The SAIL is a way to turn the ARC and GRC into a single metric from which safety objectives can be assigned. Typically each ARC and GRC combination is mapped to a SAIL value. 

Operational Safety Objectives (OSO)

Based on the SAIL determination, the SORA recommends a list of OSOs that should be met at a level of robustness corresponding to the appropriate SAIL. These OSOs provide guidance as to the recommended procedures, documentation, and training milestones necessary to ensure safe operations.

Feeling overwhelmed? We can help! 

Iris Automation’s Regulatory Resource Center is your one-stop center for preparing your BVLOS program for regulatory compliance. It includes frameworks and methodologies you can use to create risk classifications, guidance on evaluating the performance of tactical mitigation, and has samples of how proposed operational, contingency, emergency, and ground risk buffer volumes should look. 

The Regulatory Resource Center is an online tool supported by aviation policy experts providing consulting that manages the BVLOS waiver application process end-to-end for Casia system customers and other organizations looking to fly BVLOS. The RRC provides CAA access to successfully apply for BVLOS while reducing the overall time of approval. Iris Automation’s trusted aviation policy specialists have thousands of man-hours assessing operational risk and establishing compliant BVLOS flight operations with and without a DAA system.

Useful Sources

JARUS guidelines on Specific Operations Risk Assessment (SORA)

Building your Operational Risk Assessment

Strategic Mitigation Collision Risk Assessment