UAS and Manned Aircraft Autonomy

UASs have become so useful due to their ability to do jobs that have been classified, too dull, dirty, and dangerous for humans. To be able to accomplish these tasks, UAS will have to fly autonomously, that is, fly without a human directly manipulating the flight systems inside the aircraft. However, the definition can be very vague. Many UAS missions still require humans to supervision and intervention, and most times, preprogram flight paths. For this reason, most UAS can be said to be automated. However, many UAS have are becoming autonomous with varying levels of autonomy. The levels of automation range from level 0 where the pilot has complete control of the UAS to Level 5, where the UAS has control of all flying operations and tasks. For a UAS to be deemed fully autonomous, the UAS will have to control itself under all circumstances with no human intervention. This includes full automation of all flying operations under any given conditions (Radovic, 2019).     

For automation, most aircraft use autopilot systems that the pilot can switch to especially during cruise altitudes. This autopilot mode is especially useful because humans generally need rest during long periods of the task. Airbus aircraft are integrated with a fly-by-wire technology that assists the pilot makes precise control inputs during highly dynamic maneuvers with large surface controls.  stabilize the aircraft and adjust the flying characteristics without the pilot's involvement and to prevent the pilot operating outside of the aircraft's safe performance envelope.                                                                                                                             

  However, just like many current autonomous systems, humans are still required to monitor autonomous systems and take control when necessary. Although equipped with fly-by-wire technology, the A320-214 Flight 1529 that got ditched into the Hudson was able to allow the pilot to assume control of the aircraft to successfully and safely ditch. For a UAS to be deemed fully autonomous, the UAS will have to control itself under all circumstances with no human intervention. This includes full automation of all flying operations under any given conditions (Radovic, 2019). AI can be applied to UAS automaton capabilities such as sense and avoid capabilities so the UAS can precisely determine the best course of action and maneuver to avoid a collision.

Reference

Radovic, M. (2019, March 11). DroneII. Retrieved from DroneLife: https://dronelife.com/2019/03/11/droneii-tech-talk-unraveling-5-levels-of-drone-autonomy/

Physiological Issues in UAS

We all know that some drugs may compromise a pilot’s ability to control the aircraft and/or adversely affect judgment and decision making. The difficulty comes for investigators in trying to quantify the known detriment that comes with various medications and the physical conditions that require their use. The Federal Aviation Authority. The FAA has provided pilots with a list of medications that are generally safe when used to treat a common ailment (GO) and those that are not (NO-GO) (FAA, 2019). Under these guidelines, FAA says to avoid medications or ingredients that are Sedating or having a Hang-over effect. Such medications can include brompheniramine, Benadryl Dayquil Advil PM, Tylenol PM which contains diphenhydramine.

When conducting UAS operations and one needs to take OTC medications, it is generally safe to follow dosing intervals suggested by the FAA. The dosage interval suggests that If a medication says to take it 4 times per day, the dosing interval would be 6 hours and the wait time after the last dose would be 30 hours (6 hours x 5 = 30 hours). Therefore, the UAS operator can continue operation after the 30hours.

Fatigue, irritability, confusion, and other changes to your mental state such as a brain fog, which is usually characterized by memory problems, lack of mental clarity, poor concentration, and inability to focus which will make any operation of the UAS unsafe.

Reference

FAA. (2019). Retrieved from https://www.faa.gov/news/safety_briefing/2018/media/SE_Topic_18-10.pdf

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

UAM, UTM, NextGen and NAS Integration

NASA and other aviation and transportation companies like Uber and Blade are developing a system of air transport in Urban areas to solve the issues of traffic congestions. While air transportation in urban areas such as the use of helicopters has been around for a while, the focus of research and technological development has been mainly in the development and integration of Unmanned Aerial Systems (UAS). NASA has been involved in the development of safe and efficient air transport and package delivery above populated areas (NASA, 2019).

In order to safely integrate these UAM vehicles and other  unmanned aerial vehicles into the National Airspace System(NAS), NASA has partnered with other UAV developers and the Federal Aviation Authority to develop the UAS Traffic Management System(UTM), with a focus on developing technologies and procedures (NASA, 2019).The bulk of UTM flight tests involve pilots maintaining constant visual contact with the UAS. However, UTM flight research is beginning to fly extended distances. The challenge now is identifying airspace operations requirements to enable safe visual and beyond visual line-of-sight drone flights in low-altitude airspace (FAA, 2019). UTM will also work with FAA’s Next Generation Air Transportation System (NextGen) to establish procedures for effective control of airspace from the surface to 400 ft AGL. The UTM will enable the management of low-altitude uncontrolled UAS operations  (FAA, 2019).

To effectively fly Beyond Line of Vision (BLOV), UAS operating within the NAS will have to be installed detect, sense, and avoid (DSA) systems as per FAA regulations. The DSA systems which includes systems like the Automated Dependent Surveillance-Broadcast (ADS-B) and Terrain alert and Collision Avoidance System (TCAS) will help UAS meet FAA regulatory requirements for integration into the NAS.