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White and Green Phosphor NVD Comparative Assessment Army Aviation Test Evaluation Section 2
Background • 2016, aircrew from 6 Avn Regt noted that customers operating a type of Night Vision Devices (NVD) with a white phosphorous image were better able to identify obstacles than aircrew operating current AN/AVS-9 NVD with green Phosphorous Image. • Performance discrepancy was reported via a Statement of Operational Requirement from 6 Avn Regt • DACM tasked AATES to investigate. Image: Google 3
Test Objectives • Comparatively assess L3 M949 WP and GP NVD to identify if changes in NVD image colouration afforded: • Improved handling qualities • Reduced crew workload, or • Increased safety of flight for S70A-9 operations. 4
SUT Description • L-3 Warrior Systems AN/AVS-9 M949 White Phosphor Binocular Assembly Night Vision Device (Part No. 245081-044) • L-3 Warrior Systems AN/AVS-9 M949 Green Phosphor Binocular Assembly Night Vision Device (Part No. 245081-046) • Third Generation IIT • Designed with a FOM of 2376 • Auto-gating functionality • Class B filter 5
SUT Description • Green Phosphor was traditionally used in IIT because the eye is more sensitive to green light (550nm) • Early NVD had low luminance, therefore they required a colour that the eye was most receptive to. • Fatigue, object detail etc • Low Photopic Region / Scotopic – Good for dark adaptation • Monochrome – purple eye – chromatic adaptation, less sensitive to the green, looks red or blue 6
Test Aircraft • Fleet standard S-70A-9 Black Hawk Configuration 1 or 2 Helicopter • Fitted with doors, ballistic protection, Fast Roping and Rappelling Device (FFRD), Hook and Hoist • Used a DGPS fitted under deviation for as instrumentation 7
Test Inputs • AASPO and ALSMU • Technical Comparison • IAM (AVMED) • Physiological Advice • DSTG • Laboratory Performance Testing • Luminance Gain • Halo Size • Device Modulation Transfer Function • Device Spectral Power Distribution 8
Test Methodology • Ground Trial (Phase 1) • System To aircraft compatibility performance assessment was conducted at Woomera Range Facility on 25 Sep 18 • Internal Lighting Compatibility • External Lighting Compatibility • Infinity Testing 9
Test Methodology • Flight Trial (Phase 2) – • Category 2 Flight Test conducted under a MPTF approved by SO1 T&E and DOSA-FT. • 4 Specific Illumination Levels Targeted • 2 x QTP’s • MTE’s • Circuit Area Operations • Confined Area Operations • High Light Environment • Dust Operations • Coastal Operations • Flare Serials • Formation • ADS-33 Tasks • IAP to Circling Landing • Range Distance Evaluation • Workup • Area Reconnaissance • Currency for data quality 10
Test Methodology • Quantitative • Cooper Harper Handling Qualities • ADS-33 Tasks or MTE with defined desired and adequate criteria • UCE Ratings • Qualitative • Subjective Ratings • Multiple Evolutions 11
Test Instrumentation • PFPS SLAT data (Hoffman ANV-401B Night Sky Luminance meter) • Hoffman LM-33-400 Night Sky Simulation System • DGPS • Flight Data Recorder information • Laser Range Finder • Multiple cameras including Go Pro and Apple Iphone with NVD adaptor Bracket • Range resolution chart (3m x 3m) 12
Test Limitations • IAM / DSTG (availability of OEM data) • Estimated Illumination Levels (planned operations) • Application of scientific method (breadth vs. sample size) • Prolonged brownout testing not conducted • Still photography (representative not definitive) • Test Aircrew and Aircrewman (8 – exposure and data) • Widely available ‘data’ lacked scientific method and military data was unavailable (from Overseas) 13
Test Environment And Conditions • Ground Test Trial (Phase 1) was conducted from Woomera Range Facility 25 Sep 18 • Flight Test Trial was conducted from Luscombe Airfield, Holsworthy Barracks over the period 14 Nov – 06 Dec 18 • Illumination Night Illumination Definition Night Sky Level (NL) (lux) Civil and Nautical 1 Twilight 40 to <1000 Twilight 2 Light Full Moon 10 to <40 3 Intermediate < 1/2 moon 2 to <10 Starlight or 4 Very Dark < 2 Overcast 14
Results 15
DSTG Testing • Luminance, Gain and MTF, GP and WP showed equivalent results. • Device Spectral Power Distribution • The green and white L3 goggles are identical in photopic range emission (400-700 nm) • WP are 3.41 times larger in the melanopic range 16
DSTG Testing • Photopic and Melanopic Sensitivity Curve • Melanopic Receptors are only recently discovered and are sensitive to blue light (380-580nm) • Melanopic Receptors are stimulated it inhibits melatonin production which is the hormone responsible for drowsiness. • Pilots using WP NVDs could experience an increase in level alertness 17 and potentially better cognitive performance than those using GP NVD.
IAM Testing • Dark Adaptation • Conclusion: Any uncharacterised effects of dark adaptation do not impose any risk to current 2 pilot operations. • Recommendation: No change to current operations. 18
Reporting Terms TERMS USED IN CONCLUSIONS AND RECOMMENDATIONS CONCLUSION DESCRIPTION OF DEFICIENCY RECOMMENDATION RECOMMENDATION TERMINOLOGY LEVEL UNACCEPTABLE Prevents weapon system performing Something must be Essential operational task or liable to cause done. accidents – restrictions needed to prevent occurrence are considered intolerable. Restricts aircraft’s operational UNSATISFACTOR Something should be Highly Desirable Y capability, or is liable to cause done. accidents unless significant restrictions are imposed. UNDESIRABLE Could be improved to make a safer or Something could / Desirable more capable aircraft. should be done. SATISFACTORY Satisfactory without improvement. No action. N/A ENHANCING Characteristic which improves the Should be Desirable CHARACTERISTIC operational capability or safety of the incorporated in future design designs 19
Confined Area Approach • Objective. Compare task performance and workload conducting CA approaches • Conclusion: L3 M949 WP NVD reduced workload and improved accuracy when conducting CA approaches and were an ENHANCING FEATURE. • Recommendation: The acquisition of WP M949 NVD for confined area evolutions should be investigated (Desirable). 21
Highlight Environment • Objective: Comparative assessment of GP and WP NVD in Highlight Environment. 22
Highlight Environment • Conclusion: Confined Area approaches in highlight environments were conducted with reduced risk of aircraft or personnel damage using L3 M949 WP NVD and were an ENHANCING FEATURE. • Recommendation: The acquisition of WP NVD for highlight evolutions should be investigated. (Desirable). 23
Dust Approaches • Objective: Comparative assessment of GP and WP NVD during dust approaches • Conclusion: Dust approaches were conducted with reduced risk to aircraft or personnel damage on landing using L3 M949 WP NVD. • Recommendation: The acquisition of WP NVD for dust evolutions should be investigated. (Desirable). 24
Formation • Objective: Comparative assessment of GP and WP NVD during formation • Conclusion: Formation flight was conducted with greater precision and reduced workload using GP M949 and were an ENHANCING FEATURE. • Recommendation: The acquisition of GP M949 NVD for formation evolutions should be investigated (Desirable). 25
Slope Landing & Pirouette • Objective: Comparative to L3 M949 WP and AN/AVS-9 NVD, slope Landings were conducted • Conclusion: Comparative to L3 M949 WP and AN/AVS-9 NVD, slope Landings were conducted with reduced workload and improved accuracy on GP L3 M949 NVD and were an ENHANCING FEATURE • Recommendation: The acquisition of GP L3 M949 NVD for slope landing evolutions should be investigated (Desirable). 26
Range Resolution Board • Objective: Maximum range a pilot could accurately resolve elements of a spatial resolution board. 27
Range Resolution Board Inflight Range Resolution - All Illuminations 1200 1000 YSHW 21 Nov 18 100% Illum QNH 999, 21°C, Vis > 10 km, 800 Range (m) Ovcst FL150 YSHW 27 Nov 18 Twilight & 600 1/4 Moon QNH 1005, 18°C, Vis > 10 km, 400 Ovcst FL150 YSHW 05 Dec 18 0% Illum 200 QNH 1024, 22°C, Vis > 10 km, Ovcst 3000' 0 56H LH 04367 06705 GP WP GP WP GP WP GP WP GP WP GP WP GP WP GP WP 80 kts G/S, 135°, 300 ft AGL, Criteria QTP 1 QTP 2 QTP 1 QTP 2 QTP 1 QTP 2 QTP 1 QTP 2 Earlier of 3 evenly spaced 100% Illum Twilight 25% Illum Moon 0% Illum vertical or horizontal bars. • Conclusion: There was no significant difference in range distance identified between L3 M949 WP or GP NVD. • Recommendation: The acquisition of L3 M949 NVD WP or GP for target range evolutions should be investigated (Desirable). 28
High Tensile Power Lines • Objective: Comparative assessment of maximum detection, recognition, identification range of WP and GP. 266m or 6 Secs • Conclusion: The L3 M949 WP NVD were superior in detecting, recognising and identifying high tension power lines and was an ENHANCING FEATURE . • Recommendation: The acquisition of WP L3 M949 NVD for improved obstacle identification and avoidance should be investigated (Desirable). 29
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