RQ 11 Raven Operational Risk Management (ORM) Assessment Tool

The RQ Raven Small Unmanned Aerial Vehicle is one of the most frequently used UAS in the US military. With the ability to be operated in a manual or autonomous mode, it can be rapidly deployed and used in low-altitude surveillance and reconnaissance missions. With a wing spanning about 4.5 feet and weighing 4.2 pounds, the Raven can fly and ay missions for up to 10 kilometers. (Aerovironment, 2019). In order to reduce the chance of mishaps, it is important to manage the risks associated with the operation of the UAS using the Operational risk Management assessment tool.

 Preliminary Hazard List

The first task is to identify the potential hazards that will likely be encountered during operation of the UAS. This involves brainstorming with stakeholders and coming up with the potential list of hazards and then assigning a probability and severity level to the identified risks/hazards. In the list, hazards that have been identified are System Malfunctions, Loss of Link/Communication, Wrong Maintenance, Remote Pilot Error, Mid-air collision, Terrain collision, stall, flyaway, Aggressive maneuvers, and failure to launch vehicles.

Preliminary Hazard List
Track#	Hazard	Probability	Severity	RL	Mitigating Action	RRL	Notes
						1
1.	System Malfunction	occasional(C)	Critical II	3	Preventive maintenance	1
2	Loss of Link/Communication	probable(B),	Marginal	3	Reposition GCS	1
3	Wrong Maintenance	remote (D)	Critical	1	Proper Maintenance, training	1
4	Remote Pilot Error	Probable(D)	Critical	2	Proper training, procedures	1
5	Mid-air collision	Remote(D)	Catastrophic	3	Check flight data, weather conditions before the flight	1
6	Terrain collision	Probable(B)	Critical	1	Avoid High obstacle areas	1
7	Stall	Remote(D)	Critical	1	Adjust altitude	1
8	Flyaway	Remote(D)	Critical	1	Verify routes before the flight	1
9	Aggressive maneuver	Occasional (C)	Marginal	1	Return UAS to Base	1
10	Failure to launch	Frequent(A)	Critical	2	Check procedures before launch, Use mounted launch	1

Preliminary Hazard Assessment (PHA)

The next phase is to conduct a preliminary hazard analysis (PHA) by finding the best possible ways to mitigate the listed hazards or risks. Based on the listed hazards, the mitigation procedures are listed in Table 1. After the mitigation procedures are applied to the risks, another probability and severity level is conducted showing the residual risk. The residual risk is usually equal or less than the risk/hazard initially.

Operational Hazard Review and Analysis (OHR&A)

The Operational Hazard Review and Analysis (OHR&A) tool is like a preliminary hazard list. The difference is that the OHR&A is used to analyze whether the mitigation procedures adequately addressed the risks listed in the PHL. If they were not adequately addressed, they are listed again in the OHR&A.

RQ 11 Raven Risk Assessment
UAS flight training
Risk		Risk Level
		1	2	3	4
Pilot Error		Automated Pilot			Manual control
Terrain collision		Large area free of obstacles	Large area with some obstacles	No obstacle	Obstacle present in area
Failure to launch		Mounted launch			Hand launch
Stall		100-300ft AGL			400ft AGL
Total Value
Low	0-20
Moderate	21-40
High	41-60

Finally, an ORM&A table showing if it is safe to fly the UAS. Each line of risk is added to get the total risk which determines the level of risk for the mission. for example, the total of the risk assessment is 25, which places the mission at moderate risk.

Reference

Aerovironment. (2019). Retrieved from https://www.avinc.com/uas/view/raven