Expendable Countermeasure Effectiveness against Imaging Infrared Guided Threats

Size: px

Start display at page:

Download "Expendable Countermeasure Effectiveness against Imaging Infrared Guided Threats"

Logan Shepherd
6 years ago
Views:

1 Expendable Countermeasure Effectiveness against Imaging Infrared Guided Threats

4 1. Introduction Tactical Technologies Inc. (TTI) was established in 1988 as an independent EW/ECM consulting engineering and support organization. TTI s offerings include a broad range of modeling and simulation based analytical tools, technology and services related to: Platform Survivability Electronic Protection/Attack Radar guided weapons EO/IR guided weapons 7/9/2014 4

5 1. Introduction The goal of this investigation was to determine if spatially distributed flares could be effective against imaging IR-guided threats. The presentation: provides background on IIR Seeker and Expendable IRCM highlights the effectiveness evaluation process; and analyzes the results of the Monte Carlo simulation runs. 7/9/2014 5

7 2. IIR Guided Threats 7/9/2014 7

2. IIR Guided Threats Imaging IR Seekers 2D representation of an IR scene onto a focal plane array (FPA) of detectors Various sizes (128x128, 256x256, etc.

8 2. IIR Guided Threats Imaging IR Seekers 2D representation of an IR scene onto a focal plane array (FPA) of detectors Various sizes (128x128, 256x256, etc.) Better resolution with greater number of elements Typically 2 types of video trackers Gated-Video Tracker Correlation Tracker Source: TTI s SAAM(IIR) Simulator 7/9/2014 8

9 2. IIR Guided Threats Gated-Video Tracker Perimeter around a detected target is established All changes in the scene outside of that perimeter are ignored Shape of the gate can be a rectangle or can closely match the target's contour Suitable for low-clutter environments Correlation Tracker Compare all, or part of a reference image to the presented scene Can be performed in the spatial domain or the frequency domain Reference image can be static or dynamically adapted More suitable for terminal homing guidance in high clutter environments 7/9/2014 9

http://files.air-attack.com/mil/ac130/ac130u_20080829.

11 3. Infrared Countermeasures Expendable IR Countermeasures Directed IR Countermeasures Source: Source:

3. Infrared Countermeasures Spatially Distributed Flares Solid pyrophoric materials are released in the

Irradon (right) from Rheinmetall Defense (Source: http://www.rheinmetall-defence.com/index.php?

flares Typically used in pre-emptive deployment tactics SAAB Group BOL IR (Source: www.saabgroup.

12 3. Infrared Countermeasures Spatially Distributed Flares Solid pyrophoric materials are released in the vortex field behind the aircraft to create a spatially distributed radiating source Cirrus 118 (left) Irradon (right) from Rheinmetall Defense (Source: Because of the large surface to volume ratio, they decelerate even faster than MTV flares Typically used in pre-emptive deployment tactics SAAB Group BOL IR (Source: Warfare%20Solutions/BOL/BOL%20F-18%20product%20sheet.pdf) 7/9/

14 SAAM(IIR) Demo: Conventional flare deployment against imaging seeker 7/9/

15 Purpose of the investigation: to determine if a series of spatially distributed flares could effectively protect fast jets from surface-based imaging IR missiles Methodology: use a physics-based simulation to generate 1000 s of engagement runs record key engagement parameters to produce effectiveness plots modify system and deployment parameters to optimize countermeasure effectiveness 7/9/

16 Proposed Solution: To interfere with the tracking process of the imaging seeker, distributed flare(s) should: i. change the size and/or the aspect ratio of the tracking gate set on the outer perimeter of the target, and/or ii. change or mask the appearance of the target long enough to confuse the correlation process. The deployment of distributed flares in conjunction with a series of maneuvers could be used to create a partial or complete obstruction of the imaging sensor's field of view 7/9/

17 Proposed Solution (cont.): Upon warning of incoming threat, the platform should: i. Maneuver into a tail-chase engagement ii. iii. Deploy a series of distributed flares Perform evasive maneuver(s) Ideal end-game threat/target geometry with deployment of distributed flares 7/9/

18 Proposed Solution (cont.): Challenges to successful platform position concealment: Maneuvering time required in short engagement Performing the correct maneuver to get into a tailchase Accuracy of MAWS data (threat position, angle, range) Timing of distributed flare deployment Timing of evasive maneuver following flare deployment 7/9/

IRCM Assessment Tool: SAAM(IIR) physics-based simulator designed to evaluate

the latest generation of imaging IR seekers.

target platform (fixed or rotary wing) equipped with IR flares (standard,

19 IRCM Assessment Tool: SAAM(IIR) physics-based simulator designed to evaluate and assess the effectiveness of infrared (IR) countermeasures (IRCM) against the latest generation of imaging IR seekers. models the closed-loop engagement and interactions between a maneuvering aerial target platform (fixed or rotary wing) equipped with IR flares (standard, propelled and distributed) as self-protection against up to two surface or air launched imaging IR guided missiles. 7/9/

20 Engagement Setup: Parameter Variation: Threat range-to-go and angle of arrival (azimuth, elevation) Flare deployment sequence was initiated when the Threat was within the volume defined below (red conical shape): 7/9/

21 Engagement Setup (cont.): Batch Run #1 No evasive maneuvers performed Total of 1000 engagement runs executed Batch Run #2 Pull-up evasive maneuver performed Total of 1000 engagement runs executed 7/9/

22 Engagement Setup (cont.): Target/Flare Parameters Target Platform Platform Type Fast Jet Length 14 m Wing span 9 m Velocity 250 m/s Maneuver Time 0.1 sec after the depl. of the last flare Normal Acceleration 9 g Distributed Flare [Width Length Height] Growth Time Constant Sustain Time Decay Time Constant Deceleration Time Constant Decent Rate Deployment Timing [6 15 3] m 0.1 sec 2 sec 0.1 sec 0.1 m/s 0.1 m/s [ ] sec after the threat reaches the deploy range 7/9/

23 Engagement Setup (cont.): Missile/Seeker Parameters Airframe Length 1.45 m Diameter 0.1 m Wing Span 0.17 m Mass 9.2 kg Prop. Nav. Coef. 3 Max. Acceleration 30 g Seeker Servo Bandwidths 5 Hz Gimbal Limits 60 deg Field of View 4 deg Detector Array 128x128 Detector Sampling Rate 200 Hz IRCCMs None disabled 7/9/

24 Batch Run #1 Results (with no evasive maneuver): 1000 runs executed 327 runs generated a miss distance > 20 m 7/9/

25 Batch Run #2 Results (with pull-up evasive maneuver): 1000 runs executed 256 runs generated a miss distance > 20 m 7/9/

26 Simulation Results: Flare deployment inside the effectiveness region: 7/9/

27 Simulation Results: Flare deployment outside the effectiveness region: 7/9/

28 Simulation Results: Flare deployment outside the effectiveness region: 7/9/

29 Simulation Results: Flare deployment inside the effectiveness region: 7/9/

30 Key engagement parameters that will affect distributed flares effectiveness: Aircraft velocity Deployment timing between flares Dispenser(s) location on the aircraft Achievable flare size and burn duration Seeker field of view, FPA size, servo bandwidth Missile maneuverability and velocity 7/9/

31 Conclusions: The results of the investigation suggest that: at medium and long range, the distributed flare had no real impact on the threat there exists an effectiveness region where the successive deployment of distributed flares could cause a break-lock from the threat distributed flares could potentially be used as a last line of defense against imaging-based threats 7/9/

32 Future Work: Distributed flare effectiveness study: for other types of aerial platforms (military transport and helicopters) platform protection against air launched threats SAAM(IIR) Enhancements: IR environment (signature, atmospheric effects) IIR Seeker (tracking algorithms, IRCCMs) Addition of a DIRCM (imaging tracker, laser) 7/9/

33 Thank you. Questions?

10 CONCLUSIONS AND RECOMMENDATIONS

10 CONCLUSIONS AND RECOMMENDATIONS 10.1 Introduction The aim of this research work is to develop a low-cost, PC based, high-fidelity, IR signature model and simulate missile-target engagements and IR countermeasure