NASA/TM—2019–220302 

Small Unmanned Aircraft System OffNominal Operations Reporting System 

Unmanned Aircraft System Traffic Management Technical Capability 

Level 4 Implementation, Data Collection and Analysis 

Jaewoo Jung 

Ames Research Center, Moffett Field, California 

Joseph L. Rios 

Ames Research Center, Moffett Field, California 

Charles R. Drew 

Wyle Labs, Moffett Field, California 

Hemil C. Modi 

Science and Technology Corp., Moffett Field, California 

Kimberly K. Jobe 

San Jose State University, Moffett Field, California 

National Aeronautics and 

Space Administration 

Ames Research Center 

Moffett Field, California 94035-1000 

February 2020 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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NASA/TM—2019–220302 

Small Unmanned Aircraft System OffNominal Operations Reporting System 

Unmanned Aircraft System Traffic Management Technical Capability 

Level 4 Implementation, Data Collection and Analysis 

Jaewoo Jung 

Ames Research Center, Moffett Field, California 

Joseph L. Rios 

Ames Research Center, Moffett Field, California 

Charles R. Drew 

Wyle Labs, Moffett Field, California 

Hemil C. Modi 

Science and Technology Corp., Moffett Field, California 

Kimberly K. Jobe 

San Jose State University, Moffett Field, California 

National Aeronautics and 

Space Administration 

Ames Research Center 

Moffett Field, California 94035-1000 

February 2020 
This report is available in electronic form at 

https://www.sti.nasa.gov 
 

 

 

 

 

 

Table of Contents 

1. Abstract 4 

2. Introduction 4 

3. Off-nominal Reporting Setup for the TCL4 Demonstration 5 

3.1 Reporting scripted off-nominal operational situation 5 

3.2 Reporting unscripted off-nominal operational situation 7 

3.3 Off-nominal Data Model 8 

4. TCL4 Off-nominal Reports Analysis 10 

4.1 Experiential Reports 10 

4.2 Event Types 11 

4.3 Event Type Discussion 11 

5. Suggestions for the Future small UAS Off-nominal Reporting Process 12 

6. Summary 14 

References 14 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1. Abstract 

NASA performed research and development of technologies and requirements for traffic 

management of small Unmanned Aircraft Systems (UAS). In this effort, a small UAS off-nominal 

situation reporting system was developed to capture information from off-nominal situations to 

understand their nature and reduce occurrences. This Technical Memorandum (TM) describes 

the reporting system and analysis of 116 off-nominal situation reports from 352 small UAS 

operations, which were conducted at two flight test ranges in Summer 2019. 

2. Introduction 

NASA’s UAS Traffic Management (UTM) Project has been tasked with research and development 

of technologies and requirements for a small UAS traffic management system. This system is 

designed to support small UAS operations in low altitude airspace, complementing the FAA’s Air 

Traffic Management system [1,2]. The UTM Project planned a phased approach in four Technical 

Capability Levels (TCL) to accomplish the task. In TCL1, completed in 2015, Visual Line-of-Sight 

(VLOS) operations such as agriculture, firefighting, and infrastructure monitoring were addressed 

with a focus on geofencing and operations scheduling. Technologies and requirements for 

Beyond Visual Line-of-Sight (BVLOS) operations in sparsely populated areas were examined in 

TCL2 in 2016, and for operations over moderately populated areas in TCL3 in 2017 and 2018. 

TCL4 built on the earlier TCLs and focused on BVLOS operations in higher-density urban areas 

for tasks such as newsgathering and package delivery, and for managing large-scale 

contingencies [3~6]. 

The TCL4 demonstration in 2019 was a set of scenario-driven activities that integrated the UTM 

project objectives. Several scenarios were created focusing on different challenges associated 

with operations in a potential operational TCL4 environment, such as persistent, mixed tempo, 

and high-density BVLOS operations over an urban area. A total of 144 live operations were flown 

from June 18th to June 28th in the Reno, Nevada flight test range for some of the scenarios with 

nine Unmanned Aircraft (UA) made by three manufacturers. These included one vehicle from 

AirRobot GmbH & Co. KG, five from Drone America, and three from SZ DJI Technology Co., Ltd. 

Five UAS Service Suppliers (USS) developed by AirMap Inc., AiRXOS (a GE venture), ANRA 

Technologies, Avision Inc., and Uber Technologies Inc. supported the operations. A total of 208 

operations were flown from August 12th to August 16th, and August 19th to August 23rd in the 

Corpus Christi, Texas range for all scenarios with nine UA made by two manufacturers, including 

two from 3DR and seven from SZ DJI Technology Co., Ltd. Seven USS developed by AirMap 

Inc., AiRXOS (a GE venture), ANRA Technologies, Avision Inc., Collins Aerospace (a unit of 

United Technologies Corp.), OneSky (Analytical Graphics, Inc.), and Uber Technologies Inc. 

supported the operations. For all operations, arrangements were made to allow only 

demonstration participants in the defined range. Extended VLOS operations were used to emulate 

BVLOS operations. That is, the UA was in sight of designated visual observers when the operator 

was unable to see it due to obstruction (e.g., UA behind a building) or distance, and the observers 

and the operator maintained a line of communication among them to keep track of the operation. 

Details of the TCL4 demonstration are in reference [7]. 

A small UAS off-nominal situation reporting system developed in the UTM project was 

implemented by the participating USSs for the TCL4 demonstration. This system was designed 

to capture information from off-nominal situations to understand their nature and reduce 

occurrences. To test this reporting system, scripted Communications and Navigation (C&N) offnominal events, such as loss of Command and Control (C2) communication and degraded 

navigation performance, were included in the demonstration. Operators participating in such 

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events were directed to act as if their operation had encountered the scripted off-nominal situation 

and resolve the situation. The occurrence of actual (i.e., unscripted) off-nominal situations was 

anticipated and the operators were directed to prioritize safe resolution of the situation over 

scenario participation. When either scripted or actual off-nominal situations occurred, operators 

were required to submit an off-nominal report including a narrative of the situation to their 

supporting USS upon resolution of the situation. When the airborne operation became nonconforming or rogue, the report submission was required as well. A total of 116 reports were 

collected by USSs. This TM describes the TCL4 off-nominal situation reporting system 

implementation and analysis of 45 unique cases identified from the reports. Off-nominal situations 

data including the reporter narrative for the 45 cases are provided in the Appendix. The TM ends 

with suggestions for the future off-nominal reporting process. 

3. Off-nominal Reporting Setup for the TCL4 Demonstration 

3.1 Reporting scripted off-nominal operational situation 

In each of the TCL4 demonstration scenarios, one or more scripted C&N off-nominal events were 

featured. Events are changes to the operations, environment, and/or conditions that elicit a 

response from the small UAS Operator, USS, and/or UA. In particular, there are four events 

designed to test C&N off-nominal operational situations, on a small or large scale. Table 1 

describes these events. 

Table 1. Communications and Navigation Off-nominal Event 

ID Name of the 

Event 

Description 

Test 

Event 

10 

Small-Scale 

Loss of C2 

Link 

In this event at least one but not more than 25% of UA in a scenario 

encounters a loss of C2 Link condition at a specific time, 

individualized for each encounter. Each affected UA must initiate 

mitigation steps. 

Test 

Event 

11 

Large-Scale 

Loss of C2 

Link 

In this event at least 90% of UA in a scenario encounters a loss of 

C2 Link condition at a specific time and all affected UA must initiate 

mitigation steps. 

Test 

Event 

12 

Small-Scale 

Loss of 

Navigation 

In this event at least one but not more than 25% of UA in a scenario 

encounters a degraded navigation performance condition at a 

specific time, individualized for each encounter. Each affected UA 

must initiate mitigation steps. 

Test 

Event 

13 

Large-Scale 

Loss of 

Navigation 

In this event at least 90% of UA in a scenario encounters a degraded 

navigation performance condition at a specific time and all affected 

UA must initiate mitigation steps. 

The operator who participated in a scripted C&N off-nominal event was required to submit an offnominal report once the operation closed. To facilitate this submission process, USS implemented 

a feature to prompt the operator to file an off-nominal report when the following conditions 

occurred during an operation. These conditions are associated with operation states maintained 

by USS, shown in Fig. 1. Additional information about the states is in the USS specification [8]. 

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1. Operation entering NONCONFORMING state 

2. Operation entering ROGUE state 

3. Operation entering NONCONFORMING then ROGUE state 

4. Operator making UA return to the launch location, unplanned 

5. Operator making UA loiter, unplanned 

6. Operator landing UA, unplanned 

Fig. 1 Operation State Maintained by USS 

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USS developers were given the freedom to choose the reporting interface and prompting method 

as they saw fit. For example, two options were prompting operators by handing out a stand-alone 

device with an online survey form to the operator or opening a dialog window on the USS interface 

display showing a report form. A sample off-nominal reporting form provided by NASA is shown 

in Fig. 2. 

Fig. 2 Sample Off-nominal Reporting Form (filled) 

3.2 Reporting unscripted off-nominal operational situation 

In the TCL4 demonstration, the director of flight operations at the flight test range communicated 

with the operator, visual observers, and range safety personnel to manage unscripted (i.e., actual) 

off-nominal situations. Public safety officers provided support when needed. When the operation 

encountered an off-nominal situation, the operator informed the director about the situation (e.g., 

“Communications with UA is lost”). The director assessed the risk posed to the public by checking 

with the visual observers and the range safety personnel. When a risk was identified, all airborne 

operations were directed to land or loiter and planned operations were halted, depending on the 

nature of the risk. If no risk was identified or the risk was sufficiently mitigated, the operator was 

directed to return to the demonstration in progress upon the safe resolution of the situation. The 

operator was required to submit an off-nominal report before starting a new operation. 

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3.3 Off-nominal Data Model 

NASA provided a data model to USS implementers for submission of off-nominal reports to NASA, 

after the removal of Personally Identifiable Information (PII). The data model in YAML1 format is 

provided as follows. The fully expanded off-nominal data model and associated models are 

publicly available on GitHub [9]. 

OffNominalReport{ 

---- IMPORTANT NOTE ---- Please be advised: 'time_occurence' is to 

description: be included with ALL submissions of this data model (despite not being 

listed as a "required" field). -----------------------

metaDataDmpUss* metaDataDmpUss{...} 

contact PersonOrOrganization{...} 

report_id* string($uuid) 

maxLength: 36 

minLength: 36 

pattern: ^[0-9a-fA-F]{8}\-[0-9a-fA-F]{4}\-4[0-9a-fA-F]{3}\-[8-b][0-9a-fAF]{3}\-[0-9a-fA-F]{12}$ 

example: 00000000-0000-4444-8888-FEEDDEADBEEF 

A UUID assigned by the reporting USS for this instance of 

OffNominalReport. 

reason_for_report* string 

example: ROGUE 

The reason for this report. When an activated operation enters 

nonconforming or rogue state, includes scripted off-nominal event, or 

unplanned RTL, loitering, landing occurs during operation, USS must 

prompt operator to file at least one report when the operation closes. 

Reason must be one of the following Enum values: 

[NONCONFORMING, ROGUE, NONCONFORMING2ROGUE, 

UNPLANNED_RTL, UNPLANNED_LOITER, UNPLANNED_LANDING, 

VOLUNTEER]. NONCONFORMING means the operation closed after 

entering nonconforming state. When multiple nonconformances occur 

use the first one as the reason. ROGUE means the operation closed 

after entering rogue state. NONCONFORMING2ROGUE means the 

operation entered nonconforming state then rogue state then closed. 

UNPLANNED_RTL means UA made unplanned return to the launch 

location (e.g., due to unexpected low battery status). 

UNPLANNED_LOITER means UA performed unplanned loitering or 

hovering (e.g., to regain C2 link). UNPLANNED_LANDING means UA 

made unplanned landing (e.g., due to unexpected low battery status). 

VOLUNTEER means this report is filed in addition to USS prompted 

mandatory one, OR filed without USS prompt (e.g., reporter requests 

the form to be made available). 

1 “YAML” originally meant Yet Another Markup Language but has been redefined in recent years as a 

recursive acronym meaning YAML Ain’t Markup Language. 

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Enum: 

Array [ 7 ] 

scripted* boolean 

example: false 

true means operation includes scripted off-nominal event. If true, USS 

must prompt operator to file at least one report when the operation 

closes. 

contingency_id ContingencyPlan{...} 

role_responsibility* string 

minLength: 1 

maxLength: 5000 

x-utm-offnominal-prompt: Describe your role and responsibility. 

Reporter role and responsibility. Reporter MUST see the prompt text 

before inputting data. 

autopilot_maker* string 

minLength: 1 

maxLength: 1000 

maker of UA's autopilot 

autopilot_model* string 

minLength: 1 

maxLength: 1000 

UA's autopilot model 

gcs_program* string 

minLength: 1 

maxLength: 1000 

name of UAS ground control system or program 

comm_system* string 

minLength: 1 

maxLength: 5000 

x-utm-offnominal-prompt: Describe communications system including 

frequencies used for telemetry (aircraft to operator) and Command & 

Control (operator to aircraft). 

description of UAS communications system. Reporter MUST see the 

prompt text before inputting data. 

reporter_narrative* string 

minLength: 1 

maxLength: 15000 

x-utm-offnominal-prompt: Keeping in mind the topics shown below, 

discuss those that you feel are relevant and anything else you think is 

important. Include what you believe really caused the problem, and 

what can be done to prevent a recurrence, or correct the situation. 

CHAIN OF EVENTS – How the problem arose • How it was discovered 

• Contributing factors • Corrective actions. HUMAN PERFORMANCE 

CONSIDERATIONS – Perceptions, judgments, decisions • Actions or 

inactions • Factors affecting the quality of human performance 

reporter narrative about the off-nominal event. Reporter MUST see the 

prompt text before inputting data. 

flight_rule string 

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FAA rule for the operation, ONLY to be filled when value for the 

variable "reason_for_report" is "VOLUNTEER". Use the following 

Enum values: [PART_107, PART_107X, PART_101E, OTHER] 

Enum: 

Array [ 4 ] 

time_occurrence string($date-time) 

minLength: 24 

maxLength: 24 

pattern: ^([0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-

9]):([0-5][0-9]):([0-5][0-9])(\.[0-9]{3})Z$ 

example: 2015-08-20T14:11:56.118Z 

date and time of off-nominal event in UTC. 

This field is REQUIRED for all Off-Nominal Reports 

gufi* string($uuid) 

maxLength: 36 

minLength: 36 

pattern: ^[0-9a-fA-F]{8}\-[0-9a-fA-F]{4}\-4[0-9a-fA-F]{3}\-[8-b][0-9a-fAF]{3}\-[0-9a-fA-F]{12}$ 

example: 00000000-0000-4444-8888-FEEDDEADBEEF 

GUFI of the operation that is the subject of this report. 

} 

4. TCL4 Off-nominal Reports Analysis 

4.1 Experiential Reports 

Experiential incident reports were collected as part of the TCL4 UTM flight test initiative conducted 

at the Nevada and Texas test sites between June and August 2019. There were 118 initial 

experiential reports in the data set, of which 72 were from the Nevada test site, and 46 from the 

Texas test site. Of the 46 Texas reports, 2 were determined to be duplicate reports2

, and were 

therefore removed from the data set. 

In summary, there were 116 unique reports in the data set – 72 describing events at the Nevada 

test site, and 44 from the Texas test site. All available unique reports were screened and provided 

initial evaluation and classification for relevance and quality of narrative information. This 

evaluation and classification process is known as coding in aviation safety taxonomy. Of the 116 

unique reports, 71 reports contained no, or insufficient narrative data to support analysis3 ,and 

2 Duplicate reports: TCL4 Off-nominal data set Accession Numbers (ACN) 097/098, and 103/104. 3 Limited narrative or no narrative data reports: Nevada (40), Texas (31). 

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45, termed “Qualified Reports” were determined to contain sufficient qualitative narrative data to 

perform coding and analysis. 

4.2 Event Types 

Initially, a team of UTM researchers created a list of off-nominal event types to describe potential 

events in TCL4 flight testing. This list was derived from observations from previous UTM flight 

testing: 

• Exit lateral or vertical geofence 

• Lateral deviation from flight geography 

• Vertical deviation from flight geography 

• Loss of aircraft control 

• Airborne conflict with other UAS/unmanned aircraft 

• Airborne conflict with other manned aircraft 

• USS informed operator that UA was “Rogue” 

However, these previously derived event descriptions were not readily matched to narrative 

information contained in individual reports in the data set. Therefore, a more appropriate set of 

event descriptions for the TCL4 data set was developed. The events descriptions and count of 

the events from the TCL4 test are shown in Table 2. The descriptions are applicable to the TCL4 

flight test and should not be taken as a comprehensive set for UA operations in general. 

Table 2. Event Counts and Description 

Events Event Description 

19 C2 simulated loss (all were from the Nevada test site) 

7 Non-conformance with Flight Plan and/or USS requirements 

6 Ground flight control equipment problem 

5 C2 loss or interruption 

3 Track or heading deviation 

2 Navigation simulated loss 

1 Airborne conflict, with manned aircraft 

1 Aircraft equipment problem 

1 Potential conflict with other UA 

45 Unique Events 

4.3 Event Type Discussion 

Table 2 shows nine categories to capture 45 unique events. Following associates each 

category with information derived from report review. 

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C2 simulated loss (19 of 45 reports) 

Nevada conducted a simulation of loss of overall Command and Control (C2). Overall, the 

results were positive, with operators landing their vehicles in place, at an alternate landing 

site, or returning to the launch site as appropriate. Many were landed “outside of the 

operational volume,” but that would be considered acceptable in emergency or urgent 

circumstances. 

Non-conformance with Flight Plan and/or USS requirements (7 of 45 reports) 

In 7 incidents, operators did not or were unable to complete the programmed flight plan or 

were not in conformance with USS flight path and/or airspace (volume) requirements. One 

reporter noted that “USS does not have a means to schedule position holds.”, indicating 

that the USS could not dynamically update the flight plan to keep the operation in 

conformance. 

Ground flight control equipment issues (6 of 45 reports) 

iPad control issues, such as disconnection, or program failure were commonly noted in 

these reports. 

C2 Loss or interruption (5 of 45 reports) 

Several reports noted loss of communication. Two reports noted communication loss 

when line of sight data connection was interrupted by terrain or obstacles. 

Track or heading deviation (3 of 45 reports) 

In each of these reports, the reported deviation was minimal and crew were able to correct 

the deviation. In one event, the reported track deviation was only 3 to 5 feet. 

Navigation simulated loss (2 of 45 reports) 

Of the two loss of navigation reports, one reporter noted “Simulated event – loss of 

navigation. Landed on Cal Neva rooftop. In real nav loss, the aircraft would not be able 

to navigate to a safe LZ.” 

Of the remaining 3 events, 1 involved a potential conflict with a manned aircraft. The manned 

aircraft event, in which the UA did not respond as planned or directed, had a 900-foot vertical 

separation. Therefore, a Near Mid-air Collision (NMAC), defined as less than 500 feet vertical 

and 0.5 nautical miles lateral, did not occur. 

5. Suggestions for the Future small UAS Off-nominal Reporting 

Process 

During the TCLs 1 to 4, the UTM project explored different options to capture off-nominal reports 

from the UTM-participating operations, such as running a web-form server at NASA and using a 

commercial online survey service. From this exploration, submission via a USS was identified as 

the best approach for providing a reporting interface to the operator and collecting the report. 

Therefore, the following requirements were included in the USS specification [8], the baseline 

requirements for providing UAS Services within the UTM. There is an expectation that future, 

operational USSs will collect off-nominal reports. 

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When an operation enters an off-nominal condition (which would include all 

NONCONFORMING and ROGUE operations), additional reporting will be necessary. For more 

discussion and definitions for off-nominal conditions, see [UTM-OffNominal]. 

[UTM-USS-076] A USS MUST obtain an off-nominal situation report from the operator for each 

ROGUE operation. 

[UTM-USS-077] A USS MUST obtain an off-nominal situation report from the operator for each 

operation that has an unplanned return to the launch location. 

[UTM-USS-078] A USS MUST obtain an off-nominal situation report from the operator for each 

operation that has an unplanned landing. 

[UTM-USS-079] A USS MUST obtain an off-nominal situation report from the operator for each 

operation that enters an unplanned loiter. 

The definition of “unplanned” in the previous requirements relates to the active operation plan 

at the time of the landing or at the time of the loiter. It is quite possible in these cases that the 

operation goes ROGUE in the process of such a landing or loiter, but this is not necessarily the 

case. Thus, the separate requirements are needed. 

The separate requirements for unplanned landing ([UTM-USS-078]) and unplanned return to 

launch location ([UTM-USS-077]) stem from the way in which those landings may occur. For 

example manual versus automated or controlled versus uncontrolled. Through further 

discussion with stakeholders, these requirements may be refined and potentially collapsed or 

further expanded. 

[UTM-USS-080] A USS MUST obtain an off-nominal situation report from the operator 

for each operation results in the loss of the UA. 

The “loss of the UA” means either 

● a total loss of the vehicle due to a crash or hard landing, or 

● a vehicle that is unrecoverable due to its known or unknown landing location. 

[UTM-USS-081] Whenever a USS is required to obtain an off-nominal situation report from an 

operator, the USS MUST do so within 3 days of the operation completion. 

[UTM-USS-082] A USS MUST obtain data from the operator's platform per a Data Management 

Plan. 

Formatting of off-nominal situation reports will be codified in the future and may allow for 

reporting multiple events in a single form, but currently the expectation is that for each 

requirement that is met above for an operation, there will be a unique off-nominal situation. So 

an operation that goes NONCONFORMING twice would submit two reports. An operation that 

suddenly loiters and then later in the operation goes NONCONFORMING would need to file 

two off-nominal situation reports. Again, this process will be developed further in the future to 

streamline as much as possible without losing potentially vital airspace safety information. Data 

management plan details will be published in a separate document in the future. 

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For the TCL4 demonstration, the USS collected of off-nominal reports were sent to NASA and 

UTM project personnel performed evaluation and analysis. Given the scheduled closing of the 

NASA UTM project in FY 2020, it is suggested that in the future USSs should collect and submit 

off-nominal situation reports to the Aviation Safety Reporting System (ASRS) [10] so that 

evaluation and analysis continues to understand off-nominal situations and reduce their 

occurrences. This reporting should be understood as an additional process to the FAA reporting 

requirements. For example, operations under the Federal Aviation Regulations Part 107 are 

required to submit Part 107 Accident Reporting Form4 to report an accident. 

The ASRS gathers incident reports from pilots, air traffic controllers, dispatchers, cabin crew, 

maintenance technicians and others via four electronic reporting forms, General, ATC, 

Maintenance, and Cabin, and USS can use the first three forms for submitting the small UAS offnominal reports it collected. When USS fills the ASRS form, it is suggested to include data 

elements that are pertinent to small UAS operation, such as UA autopilot and ground control 

system information. The TCL4 off-nominal data model [9] should be used as a reference for 

identifying such elements. 

6. Summary 

As a part of NASA’s UTM project, a small UAS off-nominal situation reporting system was 

developed and implemented to captured information from scripted and actual (i.e., unscripted) 

off-nominal situations, from 144 small UAS operations in Reno, Nevada and 208 operations in 

Corpus Christi, Texas. A total of 116 off-nominal situation reports were collected using this 

reporting system. From these reports, 45 unique cases were identified, and this TM provides the 

description of the reporting system and analysis of the 45 cases. Given the scheduled closing of 

the NASA UTM project in FY 2020, it is suggested that in the future small UAS off-nominal 

situations reports to be sent to the Aviation Safety Reporting System so that evaluation and 

analysis continue to understand off-nominal situations and reduce their occurrences. 

References 

[1] Kopaderkar, P. et. al. “UAS Traffic Management Concept of Operations”, AIAA Paper 2016-

3292, June 2016. 

[2] “UAS Traffic Management Concept of Operations v1.0”, FAA, May 2018. 

[3] Rios, J. L., Mulfinger, D., Homola, J., and Venkatesan, P., “NASA UTM National Campaign”, 

doi: 10.1109/DASC.2016.7778080, September 2016. 

[4] Johnson, M. el. Al. “Flight Test Evaluation of UTM Concept for Multiple Beyond-Visual-Lineof-Sight Operations”, 12th USA/Europe ATM R&D Seminar, Seattle, WA, June 2017. 

[5] Homola, J. et. al. “Technical Capability Level 2 UAS Traffic Management Flight 

Demonstration: Description and Analysis”, doi: 10.1109/DASC.2017.8101994, September 2017. 

4 Available at https://faadronezone.faa.gov/#/ 

14 
 

 

[6] Aweiss, A. et. al. “Flight Demonstration of UTM at Technical Capability Level 3”, IEEE/AIAA 

38th Digital Avionics Systems Conference, San Diego, CA, September 2019. 

[7] “Flight demonstration of UTM at Technical Capability Level 4”, (to be published) 

[8] Rios, J. L. et. al. “UAS Service Supplier Specification”, NASA TM-2019-220376, October 

2019. 

[9] NASA UTM TCL4 Data Management, URL: https://github.com/nasa/utmdocs/tree/master/TCL4%20Data%20Management [retrieved 31 October 2019]. 

[10] Aviation Safety Reporting System, URL: https://asrs.arc.nasa.gov/report/electronic.html 

[retrieved 27 December 2019]. 

15 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 1 

ACN 004 

Test Site Nevada 

Date June 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter RPIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event C2 loss or interruption. 

Narrative Vehicle went out of conformance mid-flight, went back in conformance 

before 30 seconds. Reason unknown. 

Cause Unknown 

Resolution Not Reported 

Remarks Presumed to be a scripted (planned) manned aircraft incursion.

 1 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 2 

ACN 005 

Test Site Nevada 

Date June 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter RPIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event Non-conformance with Flight Plan and/or USS requirements. 

Narrative Takeoff window was delayed by several minutes. Vehicle went out of 

conformance in one volume due to missing exit window but entered 

subsequent volume, going back into (temporal) conformance. 

Cause Delay in takeoff forced enroute airspace timing problem. 

Resolution Not Reported 

Remarks

 2 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 3 

ACN 006 

Test Site Nevada 

Date June 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter RPIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event Non-conformance with Flight Plan and/or USS requirements. 

Narrative vehicle was put into position hold specified by the test card for about 8 

minutes. This caused the vehicle to miss its scheduled time window to 

move on to the next conformance volume, causing it to go rogue. Note 

that the USS does not have a means to schedule position holds. 

Cause Planned hold results in airspace violation. 

Resolution Not Reported 

Remarks

 3 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 4 

ACN 007 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model M210RTK 

Reporter RPIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event Potential conflict with other vehicles. 

Narrative Saw UVR. Invoked contingency to land safely away from UVR. 

Cause UVR. 

Resolution Aircraft was landed in accordance with contingency plan. 

Remarks

 4 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 5 

ACN 013 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Simulated C2 loss of multiple aircraft. Was advised to seek alternate 

safe landing location. Landed safely but was outside authorized volume. 

Cause Simulation 

Resolution Aircraft was landed outside protected airspace due simulated airborne 

conflict. 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 6 

ACN 014 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Alerted of major C2 loss of other aircraft and told to seek alternate safe 

landing. Safe location landed outside authorized volume. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 6 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 7 

ACN 016 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Multiple aircraft reported C2 loss, was advised to seek immediate 

landing location. Landed outside of planned route. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks Companion to ACN 107. Presumed to be a scripted (planned) manned 

aircraft incursion (repeated).

 7 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 8 

ACN 018 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Reports of massive C2 loss was announced via radio. Informed to find 

nearest safe landing location. Aircraft left volume on landing. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 8 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 9 

ACN 019 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Crew was informed C2 loss and told to find nearest safe landing 

location. Aircraft performed an automated land now procedure over the 

Pentagon Lot and landed safely. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 9 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 10 

ACN 021 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Informed of a massive C2 loss of multiple aircraft and directed to find 

nearest safe landing area. Landed in Pentagon lot, leaving volume to do 

so. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 10 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 11 

ACN 023 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Informed over radio of C2 loss and directed to find nearest safe landing 

area. Aircraft landed safely in Pentagon Lot and went outside volume as 

a result. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 11 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 12 

ACN 026 

Test Site Nevada 

Date June 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter GCS Operator 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? BVLOS 

Event C2 simulated loss. 

Narrative Precautionary landing due simulated nav loss. In real nav loss, the 

aircraft would not be able to navigate to a safe Landing Zone. 

Cause Simlulated loss of navigation capability. 

Resolution Precautionary landing due simulated navigation loss. 

Remarks

 12 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 13 

ACN 027 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Large Scale C2 loss initiated contingency plan landing in Pentagon Lot 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 13 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 14 

ACN 028 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Large Scale C2 loss initiated contingency plan landing in Pentagon Lot. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 15 

ACN 030 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Reports of large scale nav loss was reported via radio, instructed to land 

aircraft at nearest safe landing zone. Landed in Pentagon area. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 15 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 16 

ACN 032 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Ground flight control equipment problem. 

Narrative IPAD became unplugged from Ground Control Station and was showing 

as non conforming until plugged back in. 

Cause Aircraft control equipment problem. 

Resolution Insufficient information to determine cause or result 

Remarks

 16 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 17 

ACN 034 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative C2 Loss, informed to land in nearest safe position. Landed in Pentagon 

Lot. 

Cause Loss C2 of another vehicle in the area. 

Resolution Precautionary landing. 

Remarks

 17 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 18 

ACN 040 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Simulated C2 loss forced early landing at alternate landing location. 

Aircraft went rogue during the landing. 

Cause Simulated. 

Resolution Precautionary landing. 

Remarks

 18 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 19 

ACN 042 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? BVLOS 

Event C2 simulated loss. 

Narrative Aircraft had a simulated C2 loss and returned to takeoff location 

Cause Simulated. 

Resolution Precautionary landing. Return to launch site. 

Remarks

 19 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 20 

ACN 045 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Non-conformance with Flight Plan and/or USS requirements. 

Narrative UVR went in place mid-route, went rogue while transiting through UVR. 

Cause UVR causes raiuge operation. 

Resolution Not Reported 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 21 

ACN 046 

Test Site Nevada 

Date June 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter USS manager 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? BVLOS 

Event Non-conformance with Flight Plan and/or USS requirements. 

Narrative Simulated loss of NAV & went ROGUE due to going past operation time 

limits. 

Cause Simulated. 

Resolution Not Reported 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 22 

ACN 049 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Simulated C2 loss, held in place to reestablish C2 and landed in place at 

designated Contingency Area 

Cause Simulated. 

Resolution Precautionary landing. Land in place. 

Remarks

 22 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 23 

ACN 052 

Test Site Nevada 

Date June 2019 

Vehicle Make AirRobot 

Vehicle Model AR-200 

Reporter Flight Test Director. 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Non-conformance with Flight Plan and/or USS requirements. 

Narrative Vehicle launched over GCS 1 and climbed to 150' AGL. During the climb 

the operator noticed that we were inside a UVR. We took imminent 

action to send the vehicle to a safe landing location. Landing was 

complete outside volume due to UVR avoidance. 

Cause Unknown. 

Resolution Precautionary landing. 

Remarks

 23 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 24 

ACN 053 

Test Site Nevada 

Date June 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter Data Collector 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event Ground flight control equipment problem. 

Narrative Actual RTL triggered – suspected cause UgCS software error on GCS, 

or possible LTE latency. No loss of navigation. No loss of C2. 

Cause Ground control equipment software problem. 

Resolution Precautionary landing. Return to launch site. 

Remarks

 24 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 25 

ACN 054 

Test Site Nevada 

Date June 2019 

Vehicle Make DJI 

Vehicle Model M210RTK 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event C2 Loss or interruption. 

Narrative Aircraft lost connection and initiated a straight line return to home. 

Aircraft exited its conformance volume, but landed safely. 

Cause Vehicle/GCS communication loss. 

Resolution Ground control equipment software problem. 

Remarks

 25 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 26 

ACN 061 

Test Site Nevada 

Date July 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter GCS Operator 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? BVLOS 

Event Navigation simulated loss. 

Narrative Simulated event – loss of navigation. Landed on Cal Neva rooftop. In 

real nav loss, the aircraft would not be able to navigate to a safe LZ. 

Cause Simulated. 

Resolution Precautionary landing. 

Remarks

 26 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 27 

ACN 062 

Test Site Nevada 

Date July 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Large Scale C2 loss initiated contingency plan landing in Pentagon Lot. 

Cause Simulated. 

Resolution Precautionary landing. 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 28 

ACN 063 

Test Site Nevada 

Date July 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Large scale loss of C2, initiated contingency plan through USS and 

landed safely in Pentagon Lot. 

Cause Simulated. 

Resolution Precautionary landing. 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 29 

ACN 065 

Test Site Nevada 

Date July 2019 

Vehicle Make Drone America 

Vehicle Model NavXTCL4 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? BVLOS 

Event Navigation simulated loss. 

Narrative Simulated nav loss – route cut short & landed on Cal Neva rooftop. 

Cause Simulated. 

Resolution Precautionary landing. 

Remarks

 29 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 30 

ACN 066 

Test Site Nevada 

Date July 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative Reports of large scale nav loss was reported via radio, instructed to land 

aircraft at nearest safe landing zone. Landed in Pentagon area. 

Cause Simulated. 

Resolution Precautionary landing. 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 31 

ACN 068 

Test Site Nevada 

Date July 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Ground flight control equipment problem. 

Narrative iPAD became unplugged from Ground Control Station and was showing 

as non-conforming until plugged back in. 

Cause Ground control equipment problem. 

Resolution Reconnected iPad. 

Remarks

 31 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 32 

ACN 070 

Test Site Nevada 

Date July 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter PIC 

Scripted Event? No 

Simulated? Yes 

Line Of Sight? VLOS 

Event C2 simulated loss. 

Narrative C2 Loss, informed to land in nearest safe position. Landed in Pentagon 

Lot. 

Cause Simulated. 

Resolution Precautionary landing. 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 33 

ACN 073 

Test Site Texas 

Date August 2019 

Vehicle Make Tarot 

Vehicle Model X6 

Reporter GSCO 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Track Deviation. 

Narrative While on path [course], GPS began reporting right 3-5 feet from actual 

position, causing it to go rogue. 

Cause GPS tracking problem. 

Resolution Not Reported 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 

ACN 

Test Site 

Date 

Vehicle Make 

Vehicle Model 

Reporter 

Scripted Event? 

Simulated? 

Line Of Sight? 

Event 

Narrative 

Cause 

Resolution 

Remarks 

34 

074 

Texas 

August 2019 

Tarot 

X6 

GSCO 

No 

No 

Unknown 

Track Deviation. 

Took a turn a little wide, going rogue. [Track error.] 

Not reported. 

Not Reported 

34 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 35 

ACN 080 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 210 

Reporter GSCO 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Ground flight control equipment problem. 

Narrative The iPad/GCS application closed and wasn't sending telemetry for a few 

seconds till it got reopened. 

Cause GCS software problem. 

Resolution None required. 

Remarks

 35 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 36 

ACN 085 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 600 Pro 

Reporter Operator 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Non-conformance with Flight Plan and/or USS requirements. 

Narrative Need[ed] to loiter outside the volume so went non-conforming. 

Cause Unknown. 

Resolution Not Reported 

Remarks

 36 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 37 

ACN 087 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 200 

Reporter GSCO 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event C2 loss or interruption. 

Narrative UAV flew BVLOS behind building creating a low telemetry warning. 

Cause LOS communication interuption. 

Resolution UAV communication was reaquired. 

Remarks USS does not have a means to schedule position holds.

 37 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 38 

ACN 088 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 200 

Reporter GSCO 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event C2 loss or interruption. 

Narrative After UAV flew behind building, low telemetry level warning came up for 

about a second, then came back up. 

Cause LOS communication interuption. 

Resolution UAV communication was reaquired. 

Remarks Unable to determine if pilot had sufficient notice of UVR.

 38 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 39 

ACN 092 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 210 

Reporter PIC 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Ground flight control equipment problem. Non-conformance with Flight 

Plan and/or USS requirements. 

Narrative Emergency operation, received an alert, put drone in a loiter 

state. Initiated contingency plan. Attempted to use RTB button on the 

controller. Controller was lagging and was hot to the touch which caused 

an issue. New volume expired. Drone continued on original mission, 

going rogue. 

Cause Unknown. 

Resolution Anomaly accepted. 

Remarks

 39 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 40 

ACN 101 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 200 

Reporter GSO 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event Ground flight control equipment problem. 

Narrative Tablet on the PIC transmitter overheated and shut down. PIC manually 

RTL. 

Cause Ground control equipment problem. 

Resolution Crew assumed manual control and conducted RTL. 

Remarks Flight crew may not have checked to see if UVR active before departure.

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 41 

ACN 106 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 210 

Reporter GSCO 

Scripted Event? No 

Simulated? No 

Line Of Sight? VLOS 

Event Track deviation. 

Narrative GCSO updated the flight plan on Avision website but did not push the 

update to the flight controller's iPad. As a result, UAS flew according to 

the old/out-dated flight plan which made it go to a waypoint that no 

longer existed causing it to go rogue. UAS returned to the outlined path 

and landed with no issues. 

Cause Operator error. Executed Incorrect flight plan. 

Resolution UAS flew back into conformance from next waypoint. 

Remarks

 41 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 42 

ACN 107 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 200 

Reporter GSCO 

Scripted Event? Yes. 

Simulated? No 

Line Of Sight? BVLOS 

Event Airborne conflict. 

Narrative On manned AC incursion, was told to loiter but was unable to on UgCS. 

We did get low telemetry level warnings. We reloaded FP and tried to 

loiter again. Unsuccessful. Manned AC was about 1000 ft. and we were 

at 100 ft. We continued mission. 

Cause Unable to communicate with UAS, leading to airspace violation, LTSS 

with manned aircraft. 

Resolution None. Vehicles de-conflicted without intervention. 

Remarks Big sky theory.

 42 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 43 

ACN 108 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 200 

Reporter GSCO 

Scripted Event? Yes 

Simulated? No 

Line Of Sight? BVLOS 

Event C2 loss or interruption. 

Narrative In this event manned AC incursion earlier, was able to hold (loiter) UAV, 

after manned AC cleared, we were unable to continue mission due to 

low telemetry levels. After several attempts to resume mission and/or 

upload mission again, we were not able to resume mission. We decided 

to RTB immediately. 

Cause Low telemetry levels led to inability to continue mission as planned. 

Resolution Precautionary landing. Return to launch site. 

Remarks

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UTM TCL-4 Off-Nominal Data Set 

Data Set No. 44 

ACN 109 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 200 

Reporter GSCO 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event Aircraft equipment problem – low battery. 

Narrative Auto RTL due to low battery after WP 12. 

Cause Low battery level. 

Resolution Precautionary landing. Return to launch site. 

Remarks It does not seem that a 3-5 foot error should be considered a track 

deviation.

 44 of 45 
UTM TCL-4 Off-Nominal Data Set 

Data Set No. 45 

ACN 114 

Test Site Texas 

Date August 2019 

Vehicle Make DJI 

Vehicle Model Matrice 200 

Reporter GSCO 

Scripted Event? No 

Simulated? No 

Line Of Sight? BVLOS 

Event Non-conformance with Flight Plan and/or USS requirements. Altitude 

deviation. 

Narrative Having to change take off/landing elevation, I copied the same flight 

plane with way points in reverse. I didn't check the altitudes for that 

which was 70' at take off and 300' at 2nd way point which was right next 

to each other. Will fix on the next run. 

Cause Operator error. 

Resolution Not Reported 

Remarks

 45 of 45