NASA ERAST Non-Cooperative DSA Flight Test
Author / Presenter:
Russell C. Wolfe, Modern Technology Solutions Inc.
Phone: (703) 212-8870 x126
Fax: (703) 212-8874
[email protected]
www.mtsi-va.com
Executive Summary
The National Aeronautics and Space Administration (NASA) Environmental Research
Aircraft & Sensor Technology (ERAST) Non-Cooperative Detect, See, and Avoid (DSA) flight
test was accomplished between March 31st and April 4th 2003 at the Mojave Airport (KMHV)
located in Mojave, CA.
The purpose of the test was to demonstrate the ability for a remotely operated aircraft
(ROA) to detect non-cooperative manned aircraft flying on near-collision trajectories and make
the appropriate maneuver to avoid the collision; while always maintaining a minimum of 500
feet separation. To meet this objective, a 35-GHz radar was installed on the Scaled Composites
Proteus Optionally Piloted Aircraft to detect the approaching aircraft. Data from this radar was
then down linked to a ground control station, where an ROA Pilot would assess the data
displayed on his monitor. If necessary, the ROA Pilot would initiate the appropriate maneuver to
maintain safe separation and avoid the potential collision.
A total of 20 near-collision flight test scenarios were completed against seven different
manned aircraft, each with different radar cross-section characteristics. These scenarios included
both single and multiple intruder aircraft in various collision geometries (+/- 90o Az. and +/- 10o
El.) and closing speeds (30 – 610 knots). In addition, both line-of-sight and over-the-horizon
systems were used to downlink the data and uplink the commands during the flight test
scenarios.
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The Challenge
Currently ROA are permitted to operate within the National Airspace System (NAS) with
an FAA approved Certificate of Authorization (COA). However, a COA will only be approved
if the applicant meets the requirements found in FAA Order 7610.4J, which is entitled “Special
Military Operations” and dated 12 July 2001. Within this order, Chapter 12, Section 9-2
specifically addresses the operation of ROA outside Restricted Areas and Warning Areas.
Sub-paragraph a.4 of Section 9-2 states that all requests to operate ROA must provide the
FAA with the “method of pilotage and proposed method to avoid other traffic.” In addition, this
sub-paragraph goes on to state that “Approvals for ROA operations should require the proponent
to provide the ROA with a method that provides an equivalent level of safety, comparable to
see-and-avoid requirements for manned aircraft. Methods to consider include, but are not
limited to; radar observation, forward or side looking cameras, electronic detection systems,
visual observation from one or more ground sites, monitored by patrol or chase aircraft, or a
combination thereof.”
Also related to the topic of conflict avoidance is FAR Part 91.113 – Right of Way Rules.
This rule states that: “regardless of whether an operation is conducted under instrument flight
rules or visual flight rules, vigilance shall be maintained by each person operating an aircraft so
as to see and avoid other aircraft…”
In order to satisfy the requirements identified within 7610.4J and Part 91.113, all ROA
must be able to reliably avoid collisions with cooperative and non-cooperative intruder aircraft,
both in the air and on the ground. At a minimum, the ROA DSA system should provide enough
time for the ROA pilot and/or autonomous flight executive to perform the appropriate maneuver
necessary for avoiding the cooperative or non-cooperative aircraft.
Addressing the Challenge
To help address this see and avoid challenge, the NASA Environmental Research
Aircraft and Sensor Technology (ERAST) Project Office based at Dryden Flight Research
Center in Edwards, California sponsored a flight test during the week of March 31st through
April 4th, 2003. During this test, a series of 20 near-collision flight test scenarios were conducted
within the Isabella Military Operating Airspace (MOA), located near Mojave, CA (below R2508 and west of R-2515).
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The purpose of this test was to demonstrate a real-time capability for ROA Pilots to
detect, see, and avoid non-cooperative aircraft using an onboard radar and a specially developed
situational awareness DSA Display, located within the ground control station (GCS). As such,
the primary objective of this test was to demonstrate the ability of the non-cooperative system to
detect, track, and avoid non-cooperative targets using a 35 GHz, Ka-band Amphitech OASys
Radar. A secondary focus of the test attempted to assess the increased ability of the ROA Pilot
to detect, track, and avoid cooperative targets using data provided by both the cooperative
Skywatch HP traffic advisory system and the non-cooperative Amphitech OASys radar. Figure
1 depicts a concept of operations for this flight test demonstration.
Inmarsat III
AOR-W
er
Ov
ori
e -H
-th ink
L
Lineof-Sit
Link e
zon
ch
ar
e
r S me
da olu
a
R V
Inmarsat
Ground
Earth Station
Proteus GCS
(Mojave Airport)
Figure 1: Flight Test Concept of Operations
In addition to the program sponsor, NASA’s Dryden Flight Research Center (DFRC), this
test was performed with the cooperation and assistance of several NASA ERAST Alliance
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members. Participants included:
Scaled Composites, LLC (SCI),
Modern Technology Solutions
Incorporated
Amphitech
Technical
(MTSI),
International,
Analysis
and
Applications Center (TAAC),
and the Naval Air Warfare
Center (NAWC) - China Lake.
Figure 2 provides a list of these
companies and a summary of
their individual responsibilities
leading up to and during the
flight test. The success of the
test was largely due to the hard
Figure 2: Non-Coop DSA Flight Test Participants
teamwork demonstrated by all.
The key enabling technologies demonstrated within this test included the Amphitech
OASys radar [Figure 3] and the Goodrich, Skywatch HP traffic advisory system [Figure 4].
Both of these systems were integrated onto the Proteus [Figure 5] optionally piloted aircraft
(OPA) and provided the ROA Pilot, who was located in a ground control station (GCS), with the
necessary situational awareness to be capable of safely avoiding mid-air collisions.
The
Amphitech radar was installed just below the nose of the Proteus aircraft, and provided the
capability to detect all non-cooperative aircraft within +/- 85o azimuth, +/- 10o elevation, and out
to a range of 4 to 6 nmi depending upon the aircraft’s RCS signature. The orange radar search
Fig. 3: Amphitech, OASys Radar
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Fig. 4: Goodrich, Skywatch HP
4
volume depicted in Figure 1 shows the basic shape of the radar’s search volume. The Goodrich
Skywatch HP was installed just above and behind the cockpit of Proteus and provided detection
capability of all cooperative-only aircraft within +/- 9,900 feet altitude and 35 nmi range from
Proteus. The data from both of these systems was downlinked to the ROA ground control station
via either a line-of-site (LOS) telemetry link or through the Inmarsat Mini-M SATCOM system.
Both of these data-link systems were used to transmit data to the ground control station and to
transmit commands uplinked to the Proteus aircraft. Both means of data-link were alternated
throughout the 20 flight test scenarios to evaluate impacts of SATCOM latency on the overall
system performance.
Skywatch HP
Inmarsat Mini-M
Amphitech
Radar
Figure 5: Proteus OPA with Amphitech Radar and Skywatch HP Systems
Since the test largely depended upon the performance of the Amphitech radar, a variety
of non-cooperative aircraft were selected to represent a wide range of RCS signature aircraft.
These included a variety of propulsion types (single prop, dual prop, and jet) as well as structural
differences (metal, composite, and cloth). The aircraft used during the test may be seen in Figure
6 and included: a glider (composite, no engine); Stinson (cloth, single prop); Long EZ
(composite, single prop); Extra-300 (metal, single prop); Beech Duchess (metal, dual prop);
King Air (metal, dual prop); and an FA-18 Hornet (metal, jet engine). All seven intruder aircraft
were supplied by NASA DFRC and Scaled Composites. The NASA test aircraft and personnel
operated out of Edwards AFB, and the SCI test aircraft and personnel operated out of the Mojave
Airport.
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Stinson
BeechDuchess
Duchess
Beech
-
Long EZ
Extra 300
F/A-18
Glider
NASA King Air
Figure 6: Non-cooperative Intruder Aircraft
To demonstrate the ability to detect, track, and avoid non-cooperative intruder aircraft, a
series of twenty-two (22) near-collision scenarios were designed. All scenarios were performed
in accordance with the NASA ERAST Non-Cooperative DSA Flight Test Plan, Revision 0, dated
February 28, 2003 and developed by Modern Technology Solutions, Inc. This test plan, in
addition to a set of flight test cards, were the final products culminating from a five-month
planning phase leading up to the flight test activities.
Each scenario was designed and
choreographed to place Proteus and the intruder aircraft above the same location on the ground at
the same time, thereby forcing a near-midair collision scenario. Each of these scenarios also had
a 200-foot altitude separation buffer built into the intruder aircraft’s flight path for safety
reasons. Regardless of this separation buffer, a maneuver still had to be initiated by the ROA
Pilot to ensure no aircraft came within 500 feet of Proteus. Keeping all aircraft outside this 500foot bubble was one of the many evaluation criteria used for this test, and is based upon the
direction provided within FAA-Order 8700.1. This FAA Order categorizes a missed distance of
500 feet or greater as a “no hazard”, and is therefore a non-reportable incident. Anything less
than 500 feet of separation is considered reportable.
For safety precautions, the test plan also provided explicit instructions for the test pilots
to react appropriately in the case of an ABORT situation. For this, the intruder aircraft would
deconflict to a safe altitude and either set up for the next scenario or redo the current scenario.
The onboard Proteus pilots would also assume control of the aircraft and avoid the near-collision
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by operating in accordance with the ABORT procedures and returning to its initial altitude. The
ROA Pilot or any of the test pilots had authority to call an abort.
Although 22 scenarios were developed, only 20 of these could be completed. Both of the
scenarios that were not completed involved a hot-air balloon, which was unable to be flown due
to the high wind conditions in Mojave during the week of the flight test. The test scenarios
included a variety of collision geometries, a wide range of closing speeds, as well as single and
multiple intruding aircraft.
The collision geometries were confined to the radar gimbals
limitations of +/- 85o azimuth off the nose and +/- 10o elevation above and below the nose.
Some geometries were co-altitude while others involved the intruder climbing or descending into
Proteus. The closing speeds ranged anywhere from 30 KTAS for a scenario involving Proteus
overtaking the Stinson from behind, up to 610 KTAS for a head-on scenario with the FA-18
Hornet.
13 of the 22 scenarios involved a single intruder aircraft, while the remaining 9
scenarios involved two intruder aircraft approaching at the same time. Other variations included
changing the means of data-link from LOS to SATCOM. For this, 10 scenarios were controlled
using LOS while the remaining 12 were controlled using SATCOM. The last variation involved
providing radar-only data to the ROA Pilot for 9 of the scenarios and radar data plus Skywatch
data for the remaining 13. Table 1 shows how these variables changed for each scenario.
Table 1: Non-Cooperative DSA Scenarios Variable Matrix
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Some of these scenarios were designed as near-mid-air collisions, thus posing a threat to
Proteus and requiring it to maneuver, while other flight scenarios were not threatening and
therefore did not require an evasive maneuver be taken. In each scenario, it was ultimately up to
the ROA Pilot to determine which of the intruder aircraft were flying on potential collision
trajectories and which were not a concern. To do this, the ROA Pilot used the Amphitech radar
data that was downlinked to the GCS from the Proteus aircraft. When it was determined that an
aircraft was flying on a near-collision track, the ROA Pilot would initiate an evasive maneuver
from the GCS by entering a desired altitude and heading change for the Proteus aircraft using
only the computer’s keyboard and mouse. This command was then uplinked, via the LOS or
SATCOM link, to the Proteus’ onboard Flight Management System computer. This would then
cause the Proteus to perform the desired evasive maneuver at a 3o/sec rate of turn. Adjustments
to altitude and heading could be made at any time during or after the maneuver. For all 20
scenarios performed, the Proteus ROA Pilot was able to assess which aircraft posed a threat and,
if necessary, safely maneuver the Proteus aircraft while always maintaining at least 500 feet of
separation.
A specially designed display, located within the GCS, provided a “TCAS-like” DSA
display [Figure 7] of all non-cooperative aircraft (shown as red diamonds) flying within the
radar’s search volume. The DSA display also had the capability to simultaneously overlay the
Skywatch HP data onto the same screen showing the cooperative aircraft (shown as white
diamonds) within 35 nm of the Proteus. As the aircraft would move across the DSA display
screen, a track history of the intruder’s past 5 updates was also displayed using small blue
diamonds as can be seen in Figure 7. This target-track history not only enabled the ROA Pilot to
better visualize the intruder aircraft’s flight path, but also the speed of the intruder. The slower
the intruder, the closer together the blue diamonds appeared, whereas the faster the intruder the
more separation appeared between the blue diamonds. One additional feature of the DSA display
was the ability to zoom-in and get a close-up of all intruders within 4 nm or zoom-out to get a
big picture of all cooperative intruders within 35 nm. This DSA display essentially provided the
ROA Pilot with the necessary situational awareness of all cooperative and non-cooperative
intruder aircraft within the respective surveillance volume of the radar and Skywatch systems.
In addition to the DSA display, the ROA GCS also included a GPS moving map display
of where Proteus was operating, as well as all of the essential cockpit avionics essential for
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operating the vehicle. Other information located on the GCS screen included state-of-health
information, fuel-tank capacities, and data link status for the LOS and SATCOM equipment.
Proteus avionics and
State of Health data
Radar data symbol (red
diamond), showing two
aircraft: one located 300
feet below at ~3 nmi
range and one 1,400 feet
above at ~ 5 nmi range.
INTRUDERS = 3
GPS moving map
showing Proteus’
position.
- 03
Track history of
the target (small
blue diamond)
+ 14
2 Nmi
Skywatch HP data
symbol (white diamond),
showing an aircraft
located 700 feet below
and climbing (up arrow).
4 Nmi
- 07
8 Nmi
Figure 7: Proteus Ground Control Station Display
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Lessons Learned
One of the benefits to using the Proteus aircraft is the fact that there are pilots onboard
that can take over the controls of the aircraft if the ROA Pilot fails to command the appropriate
maneuver in sufficient time. Another added benefit to having human pilots on board was the fact
that they had a front row seat to the collision scenario as it developed and could provide instant
feedback following each run. The Proteus pilots, as well as the pilots of the intruder aircraft
could critique the maneuver performed by the ROA pilot by providing information such as
whether or not it was the appropriate maneuver for the given collision scenario and whether the
maneuver was made at the correct time (too soon or too late). The insight and feedback that was
provided by the pilots was formally captured in a questionnaire that was developed prior to the
flight test. Questions were asked of all test pilots and the ROA Pilot following the completion of
each scenario while everyone was setting up for the following scenario. The results of this
questionnaire were captured in the final flight test report.
Of particular interest was recording the time at which the pilots were able to first detect
the approaching aircraft. Even though the Proteus pilots had the flight cards in front of them and
knew where to look for the oncoming traffic, they typically could not see the aircraft until it was
within 1 to 1 ½ nm away. Given the high closing speeds of some of the scenarios, the pilots
often stated that they would have been very challenged to get out of the way in time to avoid the
collision.
In most of the radar-only scenarios, the ROA Pilot was usually aware of the
approaching aircraft when it was between 4 nm and 5 nm from Proteus. This variation in the
radar’s detection range was largely due to the RCS signature of the approaching aircraft. This
RCS signature could vary greatly with respect to the
aspect angle of the collision, structural material of the
intruder aircraft’s body, and the type of propulsion
system. Regardless of the scenario, the ROA Pilot was
always aware of the approaching traffic long before
the pilots on board Proteus detected the intruder
aircraft. The table to the right shows the difference in
time-to-collision, based on detection range, for a headon scenario at 500 knot closing speed. Here it can be
seen that for the onboard human pilots, a 1.5 nm
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detection range equates to having only 10.8 seconds to react; whereas for the average radar
detection range of 4.5 nm the ROA Pilot had approximately 32.4 seconds to react before
reaching the collision point.
For those scenarios where only the radar data was made available to the ROA Pilot, the
stress level largely depended upon the closing speed of the collision scenario and when/where
the intruder aircraft was first detected.
For those scenarios in which the closing speed was
between 100 to 300 KTAS and the intruder was detected at least 4 to 5 nmi away, the ROA Pilot
typically had enough time to track the intruder for several seconds, determine the collision
potential and react accordingly with an appropriate maneuver (if necessary). However, for the
scenarios that had faster closing speeds of greater than 300 KTAS and/or a detection range of
less than 4 nm to 5 nm, the ROA Pilot could not successfully complete an assessment of the
situation before exceeding his minimum time to collision. One reason for this was due to the
relatively slow update rate of the radar, which was approximately 3.5 seconds. Therefore, in a
typical 30 to 40 second timeframe following the first detection only 10 to 13 radar hits,
respectively, would be expected. The ROA Pilot would need to base his decision on when and
how to maneuver based upon this few number of radar hits. Increasing the update rate of the
DSA sensor could greatly improve the prediction accuracy of the ROA Pilot and reduce the time
needed to make a decision.
Since the developers of the test plan suspected that the radar’s range capability would not
be sufficient for the faster closing speed scenarios (those > 400 KTAS) all scenarios involving
closing speeds of > 400 KTAS allowed the ROA Pilot to have both radar and Skywatch HP data
available. For those scenarios where both the radar data and Skywatch HP data were available to
the ROA Pilot, the cooperative aircraft were almost always detected at least 15 nm away,
resulting in more than a minute of time that could be used to track the target and determine if it
might pose a potential threat. In each of the scenarios in which the ROA Pilot had both radar
and Skywatch data sets available, the comfort factor and ease of deconfliction was noticeably
improved. Quite often the ROA Pilot had ample time to think about what evasive maneuver he
wanted to make and could focus on selecting the most optimal maneuver before it was necessary
to react. One item of note was that the radar azimuth data was usually more accurate than the
Skywatch data, whereas the Skywatch elevation data was always more accurate than the radar’s
elevation data. Table 2 lists the detection ranges at which the radar and Skywatch systems first
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detected the intruder aircraft and provides whether the radar range was adequate for assessing the
scenario and allowing time for the ROA Pilot to make a well thought out maneuver.
Table 2: Detection Range of Radar and Skywatch HP by Scenario
Scenario
1**
2**
Slow Closure
3**
4**
5
6
7
8
9
10
Medium Closure
11**
12**
13**
14**
15
16
Fast Closure
17**
18
19**
Intruder
Aircraft
Closing
Speed
(KTAS)
Radar Detection
Range (nm)
Skywatch
Detection
Range (nm)
Was Radar Range
Adequate for
Scenario
Extra 300
210
4.1
16
Yes
Extra 300
210
2.5
Off
No
Extra 300
Long EZ
Extra 300
Long EZ
Stinson
Long EZ
210
220
210
220
190
220
30
(over taking)
Not
performed
Not
performed
4.2
Not detected
Not detected
2.1
3.1
3.9
Glider
Stinson
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12
Off
Yes
No
No
No
No
No
4.8
16
Yes
Not
performed
Not
performed
Not
performed
Not
performed
Not
performed
Not
performed
165
4.0
Off
Yes
Glider
165
3.5
Off
Yes
Duchess
230
4.9
16
Yes
Duchess
230
4.3
16
Yes
Duchess
230
4.2
Off
Yes
Duchess
King Air
Duchess
King Air
Duchess
King Air
230
290
230
290
230
290
4.9
Not detected
4.2
2.9
2.2
5.2
FA-18
610
6.1
18
No
FA-18
610
4.3
18
No
FA-18
610
7.2
16
No
5.1
6.2
4.3
5.1
4.1
7.4
17
20
12
20
18
16
No
No
No
No
No
No
Balloon
Balloon
King Air
290
FA-18
410
King Air
290
21**
FA-18
410
King Air
290
22
FA-18
410
** Designates scenarios flown using SATCOM
20**
Off
Off
16
12
Off
Yes
No
Yes
Yes
Yes
No
12
Post-Test Data Analysis
Following the test demonstration in Mojave, a detailed analysis of the test data was
performed to verify that all test objectives and evaluation criteria were satisfactorily met. The
data analyzed included: GPS position data collected onboard all test aircraft; FAA radar data on
all participating aircraft; Amphitech radar data gathered on all intruder aircraft, Skywatch HP
data on all cooperative aircraft within 35 nm of Proteus; Flight Management System data stored
onboard Proteus, and the data downlinked to the GCS. This data was analyzed to ensure none of
the data was degraded during the downlink/uplink telemetry, as well as ensuring that none of the
aircraft punctured the 500-foot bubble that was to be maintained throughout each collision
scenario. To verify this, several 3-D plots were generated using the GPS test data gathered on
board each test aircraft as a means to determine the closest point of approach. The 500-foot
bubble was never penetrated for any of the 20 scenarios. FAA ARSR-4 radar data was also used
to verify these results.
Figure 8, reveals an example of one of the 3-D data plots generated for all three test
aircraft flown during scenario #15. In this scenario, the Proteus was commanded to perform a
climb to maneuver above the two approaching aircraft prior to reaching the impact point (yellow
triangle). For this scenario, the closest point of approach to the King Air was 4,950 feet (green
diamond) and to the Duchess was 3,600 feet (red diamond). A complete detailed analysis of all
20 scenarios can be seen in the NASA ERAST Non-cooperative DSA Final Test Report.
13000
12500
Proteus
King Air
Duchess
12000
11500
11000
10500
10000
Altitude (feet)
13000
12500
12000
11500
11000
10500
10000
9500
9000
9500
35.5
35.45
35.4
La
titu 35.35
de
35.3
9000
35.25
-118.35
-118.3
-118.25
-118.2
-118.1
-118.15
ude
Longi t
Figure 8: 3-D Plot of Scenario #15
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Suggested Improvements to the System
Although each of the flight test objectives and supporting evaluation criteria were met,
the system did not operate flawlessly and additional software and hardware changes to the entire
system would have made the test that much more successful, and should be considered for future
testing. These modifications should include the following:
•
Displaying traffic on the ground control station relative to the aircraft’s ground track (not
body axis heading). Winds aloft made it necessary for the Proteus to crab in order to
maintain the fixed ground track required by the Test Plan. Since the GCS DSA Display
showed the intruder aircraft relative to the Proteus’ nose, the display was often misleading,
resulting in inappropriate evasive maneuvers on a few occasions.
•
Integration of predictive tools into the ground station that would provide the ROA Pilot with
course prediction and closure rate information. These tools could be similar to those used
currently by air traffic control and the CDTI software developed at NASA Ames.
•
The Amphitech OASys radar detected and tracked most aircraft at a distance of ~4.5 nm
from the Proteus. Although this range was sufficient for scenarios with less than 300 KTAS
closures, it was not adequate for the faster scenarios. Increasing the range by a factor of 2
would greatly increase the ability to detect even the fastest of collisions scenarios. However,
it should be noted here that if an ROA is autonomously maneuvered, it could be argued that
the radar’s current 4.5 nm detection range would have been sufficient for many of the faster
scenarios. Having the human in the loop forces a longer time-to-collision, which ultimately
drives the detection range outward for the faster scenarios.
•
The radar data should have been sent after each azimuth raster scan, not after every 3 raster
scans as was employed during this DSA testing. This modification would give the ROA
Pilot a faster update rate and better resolution on the intruder aircraft’s track.
•
Enhanced line of sight telemetry performance.
This could be accomplished by better
placement of the line of sight telemetry antenna on the aircraft relative to the ground station
or by increasing the power output of the transmitter.
•
Although the Inmarsat Aero Mini-M SATCOM system worked well for this test, there are
other more capable over-the-horizon systems now available. These newer systems provide
greater bandwidth, better coverage, and in many cases are cheaper to operate. The Mini-M
system relies on a gimbaled antenna that has a tendency to lose link in turns with bank angles
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exceeding twenty degrees. This link loss causes the GCS pilot to go blind at the critical time
just following a commanded maneuver.
Summary
Before ROA are allowed to operate within the NAS, the challenges associated with
detecting and avoiding other aircraft must be overcome. The NASA ERAST ROA Subsystems
project has begun to develop the sensor requirements necessary to provide an equivalent level of
safety, as well as to demonstrate a method for how this may be done in an operational
environment. The flight test, performed during the week of 31 March 2003 at the Mojave
Airport, was performed to demonstrate the ability for a ROA to detect non-cooperative manned
aircraft flying on near-collision trajectories and make the appropriate maneuver (if necessary) to
avoid the collision; while always maintaining a minimum of 500 feet separation. Data from the
commercially available Amphitech OASys radar was used by the ROA Pilot to assess the
collision scenario and then make the appropriate maneuver needed to maintain safe separation
and avoid the potential collision. It was also demonstrated that by providing the ROA Pilot with
situational awareness data from both a cooperative and non-cooperative sensor, his ability to
safely avoid the potential collision greatly increases, compared to when only one data source is
made available.
A total of 20 near-collision flight test scenarios were successfully completed against
seven different manned aircraft, each with different RCS characteristics.
These scenarios
included both single and multiple intruder aircraft, ranging in collision geometry and closing
speed. In addition, both line-of-sight and over-the-horizon data-link systems were used to
downlink the data and uplink the commands during the flight test scenarios. A formal flight test
report was written, capturing the results from the data analysis performed on all flight scenarios,
as well as providing a very comprehensive list of lessons learned gained from performing this
enabling technology demonstration.
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