New Hellfire Physical Model

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New Hellfire Physical Model

• Boris Dobrydnev
• BMH Associates, Inc.
• 5365 Robin Hood Road, Suite 100
• Norfolk, Virginia 23513-2441. U.S.A

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ProblemsNot a physical modelUnrealistic
trajectoriesNo distinction in modes and missile
generations
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PurposeRealistic physical modelSimulation of
all launch modesCorrect fly out trajectories
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Conceptual model
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Hellfire missile









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Laser Seeker Model

• Collects data on all laser spots
• Checks for laser code
• Checks for Field-of-View
• Intervisibility test
• Clouds
• Smoke

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Hellfire firing modes













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AGM-114K











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Guidance model

• Preprogrammed flight if no laser spot detected
• constant climb angle
• various values for different modes
• descent to the approximate spot location if lock
  is lost for
• AGM-114K
• If laser spot is detected
• use gravity bias (constant angle) if far from
  the spot
• move directly to the spot if close to the spot

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Flight Dynamics model
Constant acceleration for initial period of time
until the velocity reaches its maximum Air
resistance proportional to the square of velocity
for the rest of the fly out Limited turn rate











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Actual LOBL Trajectory











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Simulated LOBL Trajectory











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Actual LOAL-Direct Trajectory











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Simulated LOAL-Direct Trajectory











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Actual LOAL-Low Trajectory











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Simulated LOAL-Low Trajectory











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Actual LOAL-High Trajectory











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Simulated LOAL-High Trajectory











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Summary

• New physical model
• Successfully simulate LOBL
  and LOAL trajectories
• Enhances realism in training