Low Cost Ground Surveillance Manchester (MHT) Onsite Testing Quicklook Report

Transcription

1 Manchester (MHT) Onsite Testing Version 0.1 4/12/2012 Office of NextGen Technology Evaluations Branch ANG-C51 Federal Aviation Administration 800 ndependence Avenue, S.W. #335 Washington, DC Prepared by: U.S. Department of Transportation Volpe National Transportation Systems Center 55 Broadway Cambridge, MA 02142

2 Table of Contents Table of Contents ntroduction Test Activity Summary Onsite Test Overview Test Vehicles Test Descriptions and Results Test T1 Target Size and Detection Probability with FTR Test T2 Coverage and Accuracy with Small Aircraft Test T3 Coverage and Accuracy with Ground Vehicle Test T4 Target Resolution Test T5 Target Movement Test T6 Simulated Maneuvers with Aircraft Test T7 - Simulated Maneuvers with Ground Vehicle Test T8 Altitude Suppression Test T9 Normal Approach and Landing for Runway Test T10 Aggressive VFR Approach and Landing for Runway Test T12 Approach and Go-Around Maneuver for Runway Preliminary Assessment of External Flight Plan Data Use by the LCGS System Conclusions LCGS Technical Requirements Reference

3 1. ntroduction This report has been prepared to document the results of onsite testing of the LCGS system candidate provided by Thales and installed at Manchester Boston Regional Airport (MHT). Onsite testing was conducted at MHT during the months of February and March of An overview of the tests performed and preliminary results are presented in this report. An airport diagram is provided in Figure 1 as a reference for airport layout and taxiway labeling. The performance of the LCGS system is assessed relative to the requirements set for the LCGS program and documented in Preliminary Program Requirements for Low Cost Ground Surveillance, dated September 9, A table of the selected requirements addressed by the tests performed during onsite testing is provided in Section 5 of this report. Further investigation of these requirements will be completed during offsite evaluation of the LCGS system. Furthermore, additional system requirements not addressed during onsite testing will also be considered and evaluated. Figure 1: Airport Diagram for Manchester Boston Regional Airport 3

4 2. Test Activity Summary 2.1 Onsite Test Overview A series of tests were completed onsite at MHT using a combination of various ground vehicles, a small aircraft, a fixed radar target reflector and a Differential Global Positioning System (DGPS). Testing was conducted with the support of FAA Air Traffic Control, MHT Airport Operations and FAA Technical Operations. All onsite tests were completed during clear weather conditions. Table 1 lists the tests conducted as part of the onsite test evaluation. A detailed description of each test and results are included in Section Error! Reference source not found. of this report. Table 1: Tests Conducted During MHT Onsite LCGS Testing Test # Title Date Requirements T1 Target Size and Detection Probability with FTR 3/6/2012 R05, R06, R09, R22 T2 Coverage and Accuracy with Small Aircraft 3/12/2012 R01, R02, R06, R09, R18, R19, R22, R82, R83 T3 Coverage and Accuracy with Ground Vehicle 2/16/2012 R01, R02, R06, R09, R18, R19, R22, R82, R83 T4 Target Resolution 3/6/2012 R16 T5 Target Movement 3/22/2012 R17 T6 Simulated Maneuvers with Small Aircraft 3/12/2012 R18, R19 T7 Simulate Maneuvers with Ground Vehicle 3/6/2012 R18, R19 T8 Altitude Suppression 3/12/2012 R04, R84 T9 Normal Approach and Landing for Runway 3/12/2012 R87 T10 Aggressive VFR Approach and Landing for Runway 3/12/2012 R86, R87 T12 Approach and Go-Around Maneuver for Runway 3/12/2012 R86 Limited Assessment of System Use of External Flight Plan Data 3/17/2012 R86, R87 4

5 2.2 Test Vehicles The test vehicles and aircraft used during onsite testing are summarized in Table 2. Table 2: Test Equipment Used During Onsite Assessment of LCGS System at MHT Aircraft/Vehicle Type Width Length Cirrus SR20 Small Aircraft 35 Feet 27 Feet Ford F350 Truck 6 ½ Feet 18 Feet Toyota Highlander SUV 6 ¼ Feet 17 Feet 5

6 3. Test Descriptions and Results 3.1 Test T1 Target Size and Detection Probability with FTR The LCGS system was tested for minimum target size and detection probability with the use of a fixed target reflector (FTR). This aspect of the system was tested at six different locations utilizing a FTR with a radar cross section (RCS) of 3 m 2. The FTR is a metal trihedron with a base length of 17.3 cm for each of the triangular planes of the reflector. The dimensions of the FTR result in an effective cross-section of 3 m 2 for the 9.17 GHz frequency used by the surface movement radar (SMR) when the open end of the FTR is directed at the radar tower. For Test T1, the FTR was mounted on a tripod approximately 4 feet above the airport surface at each of the six selected test locations shown in Figure 2. The FTR was rotated in a manner to direct its open end at the surface movement radar tower. The results of this test are summarized in Table 3. The LCGS system at MHT demonstrates satisfactory performance with respect to the LCGS program minimum target size and detection probability requirements, R05 and R06. The system also meets program requirements, R09 and R22, for track update intervals. Figure 2: FTR Locations for Test T1 Test Location Time Span of Data (Seconds) Table 3: Summary of Test T1 Results LCGS Number of Detections Required Number of Detections Probability of Detection LCGS Update Gaps > 1.01 Seconds % % % % % % 0 6

7 Test T1 of the candidate LCGS system addresses the following requirements: Low Cost Ground Surveillance R05 The LCGS system sensor shall detect targets with a minimum radar cross section area of 3 m 2 within the sensor coverage area. The FTR, with a radar cross-section equivalent to the minimum target size requirement of 3 m 2 was detected at each of the six locations evaluated during this test. R06 The LCGS system shall detect a target of minimum radar cross section area within the sensor coverage area with a minimum detection probability of 90%. The minimum probability of detection was met at the six locations evaluated. Detection of the FTR at each location was continuous with an updated track status for each LCGS system track update cycle. R09 The LCGS system shall provide sensor supported target and track updates at rate of 1 ± 0.1 seconds. The track update requirement was met with LCGS system track updates occurring with a track refresh rate of 1 ± 0.1 seconds. R22 The LCGS system shall update each track at least once during each minimum update cycle. The individual track update requirement was met. 3.2 Test T2 Coverage and Accuracy with Small Aircraft A limited surface movement area coverage test was performed using a Cirrus SR20 aircraft. The test was conducted along taxiways parallel to airport runway 35 and on the runway itself. Runway 24 was only partially covered and this was done during a landing and hold short of runway 35. The SMR coverage of the eastern portion of runway 24 and the portion of taxiway J along the runway was assessed with a ground vehicle as described in Section 3.3. The airport surface area traversed during the ground coverage test in Test T2 is shown in Figure 3. The LCGS system is required to provide system track positions that are within a defined error limit with respect to the target s true position. For a target that is either stationary or traveling with an acceleration of less than 1 ft/s 2, this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow by an additional 5 feet for each 1 ft/s 2 of acceleration. The true position of the target for this test is defined as the coordinates provided by the DGPS installed in the aircraft. The minimum allowable error for LCGS provided track position is 52 ½ feet from the true position of the aircraft s centroid based on the 7 Figure 3: Path of Aircraft Ground Coverage Test

8 dimensions of the Cirrus SR20 aircraft, as summarized in Table 2, and a 10 feet allowance to account for DGPS data accuracy. A plot of the measured error in position of the track coordinates provided by the LCGS system relative to the aircraft s true position is shown in Figure 4. Only four data points had a measured positional error that exceeded the allowed limit adjusted for target acceleration. t is noted that data points associated with coasted tracks as the aircraft entered any blind spots in SMR coverage were removed. The positional data for these points is not indicative of the positional accuracy of SMR confirmed tracks for the system. Figure 4: Positional Error for Aircraft Ground Coverage Test The LCGS system demonstrates satisfactory performance with respect to the LCGS program requirements R01 and R20 for non-cooperative surveillance and track initiation. The system provides track position and velocity in a coordinate system that is in compliance with requirements R82 and R83. The system also complies with requirements R18 and R19 for track positional accuracy. Test T2 of the candidate LCGS system addresses the following requirements: R01 The LCGS system shall provide non-cooperative surveillance. The test aircraft was detected without cooperative means by the LCGS system on the taxiways and runway surfaces traversed during this test. 8

9 R18 and R19 The LCGS system shall provide system track positions that are within a defined error limit with respect to the target s true position. For non-accelerating (acceleration of less than 1 ft/s 2 ), this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow by an additional 5 feet for each 1 ft/s 2 of acceleration. Positional error remained within acceptable limits during the ground coverage test for all but four of the track updates. Overall, the positional error requirements are fully met by the system. R09 and R22 The LCGS system shall provide sensor supported target and track updates at a rate of 1 ± 0.1 seconds with each track updated at least once during each minimum update cycle. During the test, LCGS tracks were updated with a minimum refresh rate of 1 ± 0.1 seconds. R20 The LCGS system shall initiate and update tracks corresponding to detected targets. During the test, the LCGS system initiated and updated LCGS tracks upon persistent surface radar detection of a target on the surface area without user input. R82 and R83 The LCGS system shall provide track position in a Cartesian (X, Y) coordinate system in a plane tangent to the Earth s surface with a configurable system reference center. For a track position, the X-component shall be relative to true East and Y-component shall be relative to true North. The components of velocity provided by the LCGS system shall be consistent with this coordinate system. Track position and velocity components shall both be provided in a SAR message. The LCGS track information collected during Test T2 is in conformance with these requirements regarding coordinate system orientation and message packaging and transmittance. 3.3 Test T3 Coverage and Accuracy with Ground Vehicle A full surface movement area coverage test was performed using a Ford F350 vehicle. The test was conducted along taxiways parallel to airport runway 35 and runway 24. The runways themselves were also covered during this test. n addition, taxiways E, G, M, and N leading to and surrounding the airport terminal building were also included. The airport surface area traversed during the ground coverage test in Test T3 is shown in Figure 5. The LCGS system is required to provide system track positions that are within a defined error limit with respect to the target s true position. For a target that is either stationary or traveling with an acceleration of less than 1 ft/s 2, this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow 9 Figure 5: Coverage Path of Vehicle Ground Coverage Test

10 by an additional 5 feet for each 1 ft/s 2 of acceleration. The true position of the target for this test is defined as the coordinates provided by the DGPS installed in the vehicle. The minimum allowable error for LCGS provided track position is 44 feet from the true position of the aircraft s centroid based on the dimensions of the Ford F350 vehicle, as summarized in Table 2, and a 10 feet allowance to account for DGPS data accuracy. t was observed during Test T3 that some gaps in SMR coverage exist along portions of taxiway J along the east end of runway 24, taxiway J1, and parts of taxiways M, E, and N near the airport terminal building. These areas are shown with red lines in Figure 6. Overall, SMR coverage is provided for approximately 90% of the surface movement area. t is noted that placement of the SMR was optimized to reduce loss of coverage. A plot of the measured error in position of the track coordinates provided by the LCGS system relative to the vehicle s true position is shown in Figure 7. A total of Figure 6: MHT Airport Surface Areas in SMR Coverage Gap 62 data points had a measured positional error that exceeded the allowed limit adjusted for target acceleration. t is noted that data points associated with coasted tracks as the vehicle entered any blind spots in SMR coverage were removed. The positional data for these points is not indicative of the positional accuracy of SMR confirmed tracks for the system. The LCGS system demonstrates satisfactory performance with respect to the LCGS program requirement R02 for minimum surveillance coverage area. 10

11 Figure 7: Positional Error for Vehicle Ground Coverage Test Test T3 of the candidate LCGS system addresses the following requirements: R01 The LCGS system shall provide non-cooperative surveillance. The test aircraft was detected without cooperative means by the LCGS system on the taxiways and runway segments traversed during this test. R02 The LCGS system shall provide a minimum surface surveillance coverage area of rectangular shape with a 10,000 foot length and 2,000 foot width (20 million square feet). The requirement for a minimum coverage area of 20 million ft 2 is met. The sensor coverage area also meets the minimum width length of 2,000 feet and length requirement of 10,000 feet. R06 The LCGS system shall detect a target of minimum radar cross section area within the sensor coverage area with a minimum detection probability of 90%. Test T2, demonstrated that sensor coverage does not extend across the entire surface movement area. There are two regions of the surface area that are obstructed by buildings on and off the airport confines. Part of taxiways M and E are blocked by the airport terminal building. This region consists of portions of the taxiways leading to and along the terminal building. The other area where lack of SMR coverage exists is the portion of taxiway J along the east end of runway 24 and taxiway J1. This area has been masked due to obstruction and persistent reflections off of a warehouse building that lead to false targets. Overall, the vehicle ground coverage test demonstrated sensor coverage of approximately 90% of the airport movement surface area. R18 and R19 The LCGS system shall provide system track positions that are within a defined error limit with respect to the target s true position. For non-accelerating (acceleration of less 11

12 than 1 ft/s 2 ), this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow by an additional 5 feet for each 1 ft/s 2 of acceleration. Positional error remained within acceptable limits during the ground coverage test for all but 62 of the 1,834 track updates. These data points exceeding the allowed error represent 3% of the vehicles positions recorded during this test. Overall, the positional error requirements are met by the system. R09 and R22 The LCGS system shall provide sensor supported target and track updates at rate of 1 ± 0.1 seconds with each track updated at least once during each minimum update cycle. During the test, LCGS tracks were updated with a minimum refresh rate of 1 ± 0.1 seconds. R20 The LCGS system shall initiate and update tracks corresponding to detected targets. During the test, the LCGS system initiated and updated LCGS tracks upon persistent surface radar detection of a target on the surface area without user input. R82 and R83 The LCGS system shall provide track position in a Cartesian (X, Y) coordinate system in a plane tangent to the Earth s surface with a configurable system reference center. For a track position, the X-component shall be relative to true East and Y-component shall be relative to true North. The components of velocity provided by the LCGS system shall be consistent with this coordinate system. Track position and velocity components shall both be provided in a SAR message. The LCGS track information collected during Test T3 is in conformance with requirements R82 and R83 regarding coordinate system orientation and message packaging and transmittance. 3.4 Test T4 Target Resolution Target resolution of the candidate LCGS system was tested using two ground vehicles. The test was designed to determine the separation distance at which two distinct radar targets would merge into one. The system was also tested to determine the distance required before two merged radar targets would separate into distinct targets (i.e., radar plots not display tracks). The test results outlined in this section are indicative of the separation distances of the LCGS filtered radar visual feed and not LCGS initiated tracks. The visual determination of merging and unmerging of targets did not require the tagging of the ground vehicles with LCGS provided track numbers. The test was conducted with a Ford Explorer and a Ford F350 with the dimensions shown in Table 2. The test was conducted at three locations as shown in Figure 8. At each location, the Ford Explorer was driven into position and designated as the stationary target for the remainder of the test at that location. Once the Figure 8: Target Resolution Test Locations 12

13 Explorer was in position, the Ford F350 backed away from the stationary vehicle until it was clearly displayed as a separate radar target on the LCGS display. The F350 then proceeded to approach the stationary vehicle until the separate and distinct radar targets merged into one target. The distance at which this occurred was measured. Then, the F350 backed away from the stationary vehicle until two separate radar targets were again clearly noted. The distance at which radar separation occurred was also measured. This was done at each location with the F350 approaching and backing away from the Explorer from four perpendicular directions. The results of this test are summarized in Table 4. Table 4: Test T4 Results Summary Position Direction of Merge Unmerge Position Description Number Approach Distance Distance 1 Taxiway H and Runway 24 NE 44 Feet 68 Feet 1 Taxiway H and Runway 24 SW 32 Feet 56 Feet 1 Taxiway H and Runway 24 SE 46 Feet 101 Feet 1 Taxiway H and Runway 24 NW 41 Feet 63 Feet 2 Taxiway A and Taxiway C NE 35 Feet 85 Feet 2 Taxiway A and Taxiway C SW 44 Feet 88 Feet 2 Taxiway A and Taxiway C SE 31 Feet 82 Feet 2 Taxiway A and Taxiway C NW 35 Feet 54 Feet 3 Taxiway A1 and Runway 35 NE 28 Feet 60 Feet 3 Taxiway A1 and Runway 35 SW 33 Feet 76 Feet 3 Taxiway A1 and Runway 35 SE 61 Feet 100 Feet 3 Taxiway A1 and Runway 35 NW 43 Feet 101 Feet Based on Test T4, taking all cases into an average, the LCGS candidate system met the requirement: R16 The LCGS system shall resolve two targets of minimum radar cross section or greater that are separated by at least 80 feet as separate displayed targets. This requirement is met as two objects approach each other as seen by the merge distances recorded in Table 4. The displayed targets when approaching one another were merged or indistinguishable as two separate targets at a distance between feet. However, a merged pair of targets did not resolve into two clearly distinct targets as one of the objects moved away from the other until beyond 80 feet in some cases. The distance for target separation in this situation ranged from feet, with an average target separation of 78 feet with a standard deviation of 17.5 feet. 13

14 3.5 Test T5 Target Movement Resolution of target movement was tested in Test T5 at three different positions on the airport surface area as shown in Figure 9. n this test, a Ford F350 truck was brought to a stop at each test location. The vehicle was slowly driven in a radial direction relative to the surface movement radar (SMR) sensor. The distance traveled by the vehicle was measured when movement of the corresponding radar target was noted on the LCGS display. This same procedure was repeated at each location for movement in a direction tangential to the SMR. The results of this test are summarized in Table 5. The LCGS system demonstrates satisfactory performance with respect to the LCGS program requirement R17 for target movement resolution. Figure 9: Target Movement Test Locations Table 5: Test T5 Results Summary Test Location Location Description Direction of Movement Distance Traveled for With Respect to SMR Display Movement 1 NE End of Runway 24 Radial 29 Feet 1 NE End of Runway 24 Tangential 36 Feet 2 SE End of Runway 35 Radial 29 Feet 2 SE End of Runway 35 Tangential 48 Feet 3 Taxiway B and Runway 35 Radial 45 Feet 3 Taxiway B and Runway 35 Tangential 30 Feet Test T5 of the candidate LCGS system addresses the following requirements: R17 The LCGS system shall detect a minimum RCS target s movement of 50 feet or greater and display this movement. During this test, the maximum distance traveled before target movement was noted was 48 feet. Compliance with this requirement is demonstrated by the results of this test. 14

15 3.6 Test T6 Simulated Maneuvers with Aircraft A land and hold short maneuver, as depicted in Figure 10, was performed with a Cirrus SR20 aircraft. The test aircraft approached and landed on runway 6 and held short of the intersection with runway 35 before turning off on taxiway A. The LCGS system is required to provide system track positions that are within a defined error limit with respect to the target s true position. For a target that is either stationary or traveling with an acceleration of less than 1 ft/s 2, this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow by an additional 5 feet for each 1 ft/s 2 of acceleration. The true position of the target for this test is defined as the coordinates provided by the DGPS installed in the aircraft. The minimum allowable error for LCGS provided track position is 52 ½ feet from the true position of the aircraft s centroid based on the Figure 10: Land and Hold Short Maneuver Performed With Small Aircraft dimensions of the Cirrus SR20 aircraft, as summarized in Table 2, a and a 10 feet allowance to account for DGPS data accuracy. A plot of the measured error in position of the track coordinates provided by the LCGS system relative to the aircraft s true position is shown in Figure 11. Only one data points had a measured positional error that exceeded the allowed limit adjusted for target acceleration. t is noted that data points associated with coasted tracks as the vehicle entered any blind spots in SMR coverage were removed. The positional data for these points is not indicative of the positional accuracy of SMR confirmed tracks for the system. 15

16 Figure 11: Positional Error for Aircraft Maneuver Test Test T6 of the candidate LCGS system addresses the following requirements: R18 and R19 The LCGS system shall provide system track positions that are within a defined error limit with respect to the target s true position. For non-accelerating (acceleration of less than 1 ft/s 2 ), this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow by an additional 5 feet for each 1 ft/s 2 of acceleration. Positional error remained within acceptable limits during the aircraft maneuver performed for all but one of the track updates. Overall, the positional error requirements are fully met by the system. 16

17 3.7 Test T7 - Simulated Maneuvers with Ground Vehicle Test T7 included a total of three ground vehicle maneuvers that were performed with a Ford F350 truck. These manuevers included a simulated land and hold short, rapid taxi and stop, and a high speed turnoff. The high speed turnoff was performed by driving down runway 24 and turning off on taxiway M. The rapid taxis and hold short was conducted on taxiway H with the vehicle holding short of runway 24. Finally the land and hold short manuever was performed on runway 24 with the vehicle holding short of runway 35. Representations of these maneuvers are shown in Figure 12. a) b) Figure 12: Representation of Maneuvers Performed with Ground Vehicle a) High Speed Turnoff Maneuver and b) Land and Hold Short and Rapid Taxi and Stop The LCGS system is required to provide system track positions that are within a defined error limit with respect to the target s true position. For a target that is either stationary or traveling with an acceleration of less than 1 ft/s 2, this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow by an additional 5 feet for each 1 ft/s 2 of acceleration. The true position of the target for this test is defined as the coordinates provided by the DGPS installed in the vehicle. The minimum allowable error for LCGS provided track position is 44 feet from the true position of the aircraft s centroid based on the dimensions of the Ford F350 vehicle, as summarized in Table 2, and a 10 feet allowance to account for DGPS data accuracy. Plots of the measured error in position of the track coordinates provided by the LCGS system relative to the aircraft s true position for each maneuver are shown in Figure 13. All data points collected during the maneuvers conducted during this test had a measured positional error that was within the allowed limit adjusted for target acceleration. 17

18 a) b) Figure 13: Positional Error for Simulated Ground Vehicle Maneuvers Test a) High Speed Turnoff Maneuver, b) Land and Hold Short and c) Rapid Taxi and Stop c) Test T7 of the candidate LCGS system addresses the following requirements: R18 and R19 The LCGS system shall provide system track positions that are within a defined error limit with respect to the target s true position. For non-accelerating (acceleration of less than 1 ft/s 2 ), this limit is defined by a distance no greater than 25 feet outside of the smallest circle that fully encloses the target. The error is allowed to grow by an additional 5 feet for each 1 ft/s 2 of acceleration. Positional error remained within acceptable limits during the simulated vehicle maneuvers performed, except for two data points during the rapid taxi and stop. Overall, the positional error requirements are met by the system. 18

19 3.8 Test T8 Altitude Suppression Test T8 was designed to investigate the track suppression feature of the candidate LCGS system. During this test, a flyover of MHT Runway 35 was performed at approximately 180 feet above ground level (AGL). This was then followed by a second flyover at approximately 280 feet AGL. The first flyover at 180 feet AGL was detected and displayed on the LCGS system display. However, the second flyover at 280 feet AGL was not displayed on the LCGS system display. The results of this test demonstrate compliance with requirement R04 which states that vertical coverage extend more than 50 feet AGL but less than 500 feet AGL is met. Test T8 of the candidate LCGS system addresses the following requirements: R04 The LCGS system vertical coverage shall extend from the surface to a height greater than or equal to 50 feet AGL but not greater than 500 feet AGL. This requirement was met as demonstrated by LCGS display of the flyover at 180 feet AGL, but not at 280 feet AGL. R84 The LCGS system shall provide the capability to filter display of tracks associated with external surveillance tracks that include altitude information and exceed a site adaptable altitude threshold where the threshold value is specified in units of feet above ground level. A user defined parameter setting the altitude threshold for external track data may be set in the LCGS system interface. 3.9 Test T9 Normal Approach and Landing for Runway A normal approach and landing was performed on Runway 35 with a Cirrus SR20 aircraft. The intent of this test was to assess the system with regards to requirements R86 and R87 which relate to automatic tag generation from externally provided flight plan data and maintenance of tag association. The Standard Terminal Automation Replacement System (STARS) provided track data block information for the test aircraft including callsign. The LCGS system uses a coasting algorithm to transition data from the externally supplied flight plan data onto a coasted LCGS track prior to the aircraft being detected by the SMR. The LCGS system automatically acquired the callsign tag from STARS during test T9 and applied it to the LCGS track during the track coasting phase. However, the tag was then rejected by the LCGS system for the track once the LCGS surface radar acquired the aircraft. The coasting algorithm attempts to match the coasted track with a surface radar track by comparing position. The two are correlated if the positions of the coasted and actual track are within a set distance from one another. n this case, the coasted track was not correlated to the LCGS SMR track and the STARS flight plan data on the coasted track was not transferred. 19

20 The LCGS system at MHT demonstrates satisfactory performance with respect to the LCGS program requirements R86 and R87 for the use of external flight plan data. Test T9 of the candidate LCGS system addresses the following requirements: R86 Displayed tracks shall be automatically associated with a displayed data block including the flight plan data available externally from the LCGS system when the flight plan can be associated with the track. According to the requirement, the LCGS track was correctly assigned the externally provided tag during coasting. R87 Once associated, data block information provided for displayed tracks shall be maintained correctly. The callsign provided to LCGS from STARS was not retained on the LCGS track after the coasting phase was completed. The system appropriately dropped the data block information when it could not adequately match an LCGS radar track with the tagged coasted track Test T10 Aggressive VFR Approach and Landing for Runway An aggressive VFR approach and landing was conducted with a Cirrus SR20 aircraft on Runway 35. The intent of this test was to further assess the system with regards to automatic tag generation and maintenance of association. The maneuver was successfully completed without any automatic tag generation by the LCGS system. This is likely a result of the aggressive approach and the design of the LCGS coasting algorithm. The test aircraft in this maneuver entered the system s coasted track initiation region in an unexpected manner and the system did not initiate a coasted track. Therefore, there was no transition of flight plan data to the LCGS system for track association when the aircraft was detected by the SMR. Regardless, the system meets requirements R86 and R87 by not incorrectly tagging the LCGS track of the aircraft upon touchdown. Test T10 of the candidate LCGS system addresses the following requirements: R86 Displayed tracks shall be automatically associated with a displayed data block including the flight plan data available externally from the LCGS system when the flight plan can be associated with the track. According to the requirement, the LCGS track for the aircraft during the maneuver was not assigned an externally provided tag. The system could not definitively associate the LCGS track with an externally provided track and related data block information. R87 Once associated, data block information provided for displayed tracks shall be maintained correctly. A tag was never assigned to the LCGS track, therefore making this requirement for track tag retention irrelevant during this test. 20

21 3.11 Test T12 Approach and Go-Around Maneuver for Runway Low Cost Ground Surveillance An approach and go-around maneuver was performed using a Cirrus SR20 aircraft on Runway 35. The external STARS track of the aircraft included a data block with an aircraft callsign. The LCGS system automatically acquired the callsign tag from STARS and applied it to the LCGS track during the track s coasting phase. However, the tag was then rejected from the track once the LCGS SMR acquired the aircraft. The coasted track was not correlated to the radar target due to too large a difference between the coasted track position and the actual target position upon SMR acquisition. Test T12 of the candidate LCGS system addresses the following requirements: R86 Displayed tracks shall be automatically associated with a displayed data block including the flight plan data available externally from the LCGS system when the flight plan can be associated with the track. According to the requirement, the coasted LCGS track was correctly assigned data block information provided externally from the LCGS system Preliminary Assessment of External Flight Plan Data Use by the LCGS System A limited assessment of the system capability and efficacy in utilizing external flight plan data from the FAA (STARS) was conducted. The LCGS track info and STARS broadcast messages were collected over the period of one day to determine the integration performance of the two systems. Tools and a methodology were developed to automate the assessment of the data use. The auto-match of LCGS generated tracks to STAR provided data was reviewed with two components evaluated. First, the transition of STARS callsign data to LCGS tracks was considered. Second, the maintenance of autotagged LCGS tracks callsigns was assessed. A more extensive evaluation of the system capability will be conducted on data collected over a longer timeframe. The LCGS requirements with regards to LCGS system use of external flight plan data include: R86 LCGS tracks, when appropriate, shall be automatically associated with flight plan data available externally from the LCGS system with a minimum probability of correct initial association (PCA) of 99%. R87 Once associated, either by automatic or manual methods, data block information provided for LCGS tracks shall be maintained correctly with a probability of correctly maintained association (PCMA) of 99%. t is not required for the system to automatically tag targets from externally provided flight plan data if the system cannot associate the external and LCGS tracks with sufficient certainty. t is preferred that the 21

22 system not initiate data block information for an incoming track if the correlation between the LCGS and STARS track is not certain. t is also preferred that the LCGS system drop the data block information for a LCGS track if it is uncertain of the continued validity of the tag. Data for a preliminary assessment of PCA and PCMA was collected for the full day of March 17 th, A total of 52 arrivals occurred with corresponding STAR callsigns. Of these arrivals, a total of 46 of them were associated with either a coasted or SMR substantiated LCGS track. This association resulted in correct initiation of the LCGS track data blocks for all cases resulting in a percentage of correct initial association of 100%. The data block information was correctly maintained and then dropped as appropriate per LCGS program requirements resulting in a PCMA of 100%. The preliminary assessment demonstrates accordance of the LCGS candidate system with the following requirements: R86 Automatic initiation of LCGS track data blocks with information from externally provided flight data shall result in a minimum probability of correct initial association (PCA) of 99%. The preliminary results show a percentage of correct initial association of 100% for the data sample considered. A more extensive pool of data will be collected to perform a statistical assessment to infer PCA. R87 Maintenance of LCGS track data blocks with information from externally provided flight data or manual tagging shall be maintained correctly with a probability of correct maintained association (PCMA) of 99%. The preliminary results show a percentage of correct maintained association of 100% for the data sample considered. A more extensive pool of data will be collected to perform a statistical assessment to infer PCMA. 22

23 4. Conclusions All requirements, as outlined in this report, for the candidate LCGS system installed at Manchester Regional Airport were met. Additional observations and areas for consideration highlighted by onsite testing include the following: t is known that a few areas of the airport surface area are not provided coverage by the surface movement radar (SMR) due to obstructions by an offsite warehouse and the airport terminal building. These areas include the very end of Runway 17, taxiways J and J1 leading onto Runway 17, and parts of taxiways M and N. Radar detection and LCGS track initiation and track maintenance are not available in these reasons. n addition to lacking radar visual feed, a LCGS numbered and labeled track will lose its track identification when passing in these no-coverage regions. When reinitiated after re-entering the SMR coverage area, these targets will not be labeled and likely will not be assigned the same LCGS track number. A number of aircraft initiated LCGS coasted tracks with correct data block association from STARS, but the data block information was not always transferred to the LCGS ground track. The coasting algorithm attempts to extrapolate the aircraft position as it enters a defined area near the end of a runway on approach. This extrapolation is based off the last known STARS position and a system set average speed. n some cases the extrapolated track either lags or precedes the actual aircraft by too large a distance for the system to associate the coasted track to the actual ground track when it is initiated by the system. As a result, the system does not transfer the data block data from STARS to the LCGS ground track. This is acceptable per the program requirements, but reduces the overall number of cases where this feature is employed. 23

24 5. LCGS Technical Requirements Reference A complete list of requirements for the LCGS Program is documented in Preliminary Program Requirements for Low Cost Ground Surveillance, dated September 9, This report addresses each requirement as currently written as of the date of publication. t is noted that requirements may change and affect the observations from the testing results detailed in this report. A table summarizing the LCGS requirements addressed by the onsite testing discussed in this report is found below in (). This table, referred to as the Verification Requirements Traceability Matrix (VRTM) provides a requirement number, requirement verbiage and verification method(s) to be used for evaluation. The verification methods are categorized as A for analysis, for inspection, and T for test. The verification methods used in Table 6 are defined generally as: 1. Analysis is a method of verification where hardware or software design information is compared with known scientific and technical principles, procedures, and practices to estimate the capability of the proposed design to meet the requirements. 2. nspection is a method of verification to determine compliance without the use of special test equipment, procedures, or services, and consist of a non-destructive static-state examination of the hardware, software, and/or the technical data and documentation. 3. Test is a method of verification wherein performance is measured during or after the controlled application of functional and/or environmental stimuli. Quantitative measurements are analyzed to determine the degree of compliance to the performance requirements. The process uses standardized laboratory equipment, procedures, hardware, and/or services. Table 6: VRTM Table R# Requirement Verification Methods R01 The LCGS system shall provide non-cooperative surveillance. A, T R02 The LCGS system shall provide a minimum surface surveillance coverage area of rectangular shape with a 10,000 foot length and a 2,000 foot width (20 T million square feet) wherein all requirements must be met. R03 The LCGS system surface surveillance coverage area shall be scalable to over a maximum surface surveillance coverage area of 100 million square feet, A wherein all requirements must be met. R04 The LCGS system vertical coverage shall extend from the surface to a height greater than or equal to 50 feet above ground level (AGL) but not greater than 400 feet AGL wherein all requirements must be met over the surface, A surveillance coverage area. R05 The LCGS system sensor(s) shall detect targets with a minimum radar cross section (RCS) area of 3 m 2 within the sensor surface surveillance coverage area. T 24

25 R# Requirement R06 R07 R08 R09 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 The LCGS system sensor(s) shall detect all targets of minimum RCS within the sensor surface surveillance overage area and in accordance with the system s minimum update rate, with a minimum detection probability (PD) of 90% and with a maximum probability of false alarm (PFA) of The LCGS system shall automatically initialize and begin operation within 15 minutes of startup. The LCGS system shall operate in accordance with all requirements without the need for manual adjustments once optimized. The LCGS system shall provide sensor supported target and track updates at an update rate of once every second, plus or minus 0.10 seconds. The LCGS system shall maintain the target and track update rate under wind loading conditions of up to 85 knots. The LCGS system shall monitor operational status and key system performance parameters. The LCGS system shall log and timestamp operational status changes of the overall system. The LCGS system shall log an timestamp operational status changes of the system sensors. The LCGS system shall log and timestamp changes to key system performance parameters. The LCGS system shall preserve logs for a minimum of 12 weeks to a maximum of 26 weeks. The LCGS system shall resolve two targets of the minimum RCS or greater that are separated by at least 80 feet as separate displayed targets or tracks. The LCGS system shall detect a minimum RCS target s movements of 50 feet or greater and display this movement to the user. The LCGS system shall locate the centroid position of any non-accelerating (acceleration less than or equal to 1 foot per second per second) target or track that is correlated with the true position of the aircraft or vehicle with an error no greater than 25 feet outside of the smallest circle that fully encloses the aircraft or vehicle. The LCGS system shall locate the centroid position of any particular accelerating (acceleration greater 1 foot per second per second) target or track that is correlated with the true position of the aircraft or vehicle with an error no greater than 25 feet outside of the smallest circle that fully encloses the aircraft or vehicle plus 5 feet per foot per second per second times the magnitude of the directional acceleration (listed in feet per second per second). The LCGS system shall initiate and update tracks corresponding to detected targets. The LCGS system shall initiate tracks within a configurable number of successive target reports after the initial report where the configurable number is an integer ranging from 1 to 5. The LCGS system shall update each track at least once each minimum update cycle. The LCGS system shall coast the track positions which are not updated by sensor plot reports at least once per minimum update interval. Verification Methods T D A T A D D D D A T T T T T, D T T 25

26 R# Requirement R24 R25 R26 The LCGS system shall drop tracks after a configurable number of successive system update intervals where no target is detected and associated with the track where the configurable number is an integer ranging from 1 to 5. The LCGS system shall produce no more than 2 false tracks in any hour of operation. The LCGS system shall produce no more than 2 track anomalies other than false tracks in any hour of operation where other track anomalies include split tracks, merged tracks, and swapped tracks. Low Cost Ground Surveillance Verification Methods R27 The LCGS system shall provide four Air Traffic Control (ATC) user displays. R28 The LCGS system shall display a color presentation of the airport surface movement area, and of all stationary/moving aircraft and ground vehicles within these areas. R29 The LCGS system shall indicate overall system health on all displays. R30 The LCGS ATC user display shall distinguish five kinds of map areas in the airport surface movement area including runways, taxiways, ramps, background 1 and background 2. R31 No map area shall cover or interfere with the presentation of a target or track icon or data block. R32 Each map area be displayed in an independent color. R33 Areas that are not represented by the five defined map areas shall display the root color. R34 Runway map area shall include all runway surface areas. R35 Runway map area shall include all helicopter landing areas. R36 Taxiway map area shall include all taxiway surface areas. R37 Taxiway map area shall include all non-taxiway movement areas. R38 Taxiway map area shall include all helicopter taxiing areas. R39 Ramp map areas shall include loading ramps, parking areas, and other noncontrolled movement areas near the terminal. R40 Background 1 map areas shall include islands between runways and taxiways and areas outside of runways and taxiways. R41 Background 2 map areas shall include other significant geographical landmarks such as bodies of water, roadways, buildings, bridges. R42 All colors shall be constructed using standard RGB value sets. R43 The system configuration parameters shall include two or more color palettes. R44 The ATC display shall allow the user to select from two or more color palettes for display during operation. R45 Each color palette shall include colors defined for the display components including root color, runways, taxiways, ramps, background 1, background 2, generic target icon, cursor, and data block text. R46 R47 R48 All fonts shall be a non-proportionally spaced font in the sans serif class of fonts. A single target icon type shall be used to represent the location of all aircraft, ground vehicles, and other detected moving or stationary objects. The target icon shall present the location of the target on the map display window., D A A 26

27 27 Low Cost Ground Surveillance R# Requirement Verification Methods R49 The location of the target is defined as the centroid of the target aircraft, ground vehicle, or other detected object. R50 Line 1 of the data block shall display the aircraft identification (also referred to as the ACD or call sign information). R51 Line 2 of the data block shall display the aircraft type abbreviation using four characters, followed by a space and then a single character with the aircraft category abbreviation. R52 Line 2 of the data block shall be used in a timeshare manner with a manually created text field (if such field has been defined for a target) where the contents of line 2 alternate every two seconds. R53 The LCGS system shall support a manually created text field to be shown within the data block. D R54 The LCGS system shall support manual creation of a text field to initiate a new data block or update an existing data block with a method for the operator to D input the text field and associate it with a track. R55 The LCGS system shall edit data block information manually after creation and association with a displayed track. D R56 The information in the data block shall always be horizontal and readable from left to right when the display is upright. R57 The data block shall be in one of eight positions relative to the centroid of the target icon including, up, down, left, right, diagonally up to the right, diagonally down to the right, diagonally up to the left, diagonally down to the right. R58 The user shall select the position of the data block relative to the target icon. R59 A leader line shall originate at the centroid of a target icon and terminate at the data block at the point of the data block closest to the target icon depending on the relative position. R60 The default length of the leader line shall be adaptable by selecting system startup parameters for a range of between 0 and 1.5 long with 0.1 increments allowed. R61 The user shall enable or disable display of all data blocks. R62 The hardware display shall support 16,777,216 distinct colors. R63 The hardware display shall be readable in direct ambient lighting conditions within the air traffic control tower cab. R64 The hardware display shall have a minimum viewing angle of +/- 80 degrees horizontal and vertical. R65 The hardware display shall have a diagonal size of 20 inches. R66 The hardware display shall support mounting from the ceiling. R67 An articulated ceiling mount having vertical and lateral adjustment as well as monitor tilt and swivel capability shall be provided where the vertical adjustment may be up to 18 inches minimum and the lateral adjustment may be anywhere within a minimum of a 40 inch radius, 180 degree arc about a center post. R68 The hardware display shall support mounting on a table top. R69 A freestanding table top mount having monitor tilt and swivel capability shall be provided.