SafeSafe SeparationSeparation AnalysisAnalysis ofof thethe InternalInternal GBUGBU--3232 JDAMJDAM fromfrom JSFJSF MSC.Software VPD Conference July 17-19, 2006
Chris Hetreed, Monique Purdon, Mary Hudson Lockheed Martin Aeronautics Company Fort Worth, TX
Lockheed Martin Aeronautics Company 1 Lockheed Martin Aeronautics Company 2 JCS Threshold Weapon Requirements
InternalGD-425 GBU-38 JDAM 500-lb (CTOL) (MK-82 Warhead) AMRAAM C CBU-103 / 104 / 105 WCMD
GBU-32 JDAM 1,000-lb (MK-83/BLU-110 Warhead) AIM-132 ASRAAM CBU- 87 / 89 Brimstone / Joint Common Missile Cluster Munition Brimstone GBU-31 JDAM 2,000-lb BDU-57/59/60 (BLU-109 Warhead) Laser-Guided Training Round AGM-154 A/C JSOW Glide Bomb MK-76 s AIM-120B on p * BDU-48 / MK-58 GBU-31 JDAM 2,000-lb ea ns (MK-84 Warhead) W o AIM-120 C al ap JDAM PGK (BLU-109 & MK-82) rn e e l W nt a UK 500# PGB GBU-12 Paveway II 500-lb LGB I rn Missionized Gun Pod (MK-82 Warhead) te {CV / STOVL} Ex GBU-12 Paveway II 500-lb LGB Phase I SDB (MK-82 Warhead) UK 500# PGB AGM-65 Maverick (If 1760 compliant) GBU-10 Paveway II 2,000-lb LGB (MK-84 Warhead) MK-82 BLU-111 500-lb LDGP AIM-9X Sidewinder GBU-31 JDAM 2,000-lb CBU-99/100 (MK-84 / BLU-109 Warhead) Rockeye II Cluster Munition AIM-132 ASRAAM GBU-16 Paveway II 1,000-lb LGB MK-82 BLU-111 BSU-49 Ballute (MK-83 Warhead) 500-lb HDGP MK-84 BSU-50 Ballute 2,000-lb HDGP AGM-88 HARM MK-83 BLU-110 LDGP 1,000-lb LDGP (If 1760 compliant) AGM-158 JASSM GBU-24/B Paveway III 2,000-lb LGB (MK-84 / BLU-109 Warhead) MK-83 BSU-85 HDGP
Stormshadow MK-84 2,000-lb LD/HDGP 426-Gallon Wing Tank Lockheed MartinMXU-648/CNU-88 Aeronautics Baggage Company Pod Store Fully Certified During EMD * Including All Internal Weapons 3 DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited Weapons Stations
Station 11 10 9 8 7 6 5 4 3 2 1
Store A/A A/A, A/S A/A, A/S A/A, A/S A/A A/S A/A A/A, A/S A/A, A/S A/A, A/S A/A CTOL/CV 300 2,500 5,000 2,500 350 1,000 350 2,500 5,000 2,500 300 Weight STOVL 300 1,500 5,000 1,500 350 1,000 350 1,500 5,000 1,500 300 Weight • Over 18,000 Lbs Ordnance Capacity • Nonpyrotechnic Suspension and Release
Lockheed Martin Aeronautics Company 4 DISTRIBUTION STATEMENT A: Approved for public release; distribution is unlimited F-35 JSF Store Separation Analysis
Objective: Demonstration of the process used by the F-35 JSF Store Separation team to analyze the pre-flight safe separation of the GBU-32 JDAM.
Topics: – Store Separation 3 Step Process – Flowfield Studies: New Grid Collection Methods – In-Bay Aerodynamic Loads Modeling – Innovative Techniques for Database Building, Validation, and Flight Clearance Envelope Generation – Applying MSC.Adams & VI-AirCraft to Store Separation Applications
Lockheed Martin Aeronautics Company 5 JSF Store Separation 3-Step Process
Step 1: Validation Grid Data N 6DOF GEMD+ GEMD Database =CTS Traj? 6DOF (ADAMS) Y OK
Grid Data N =CTS Aero? Y
Step 2: Flight Envelope
6DOF Miss Flight Distance Clearance (M,Alt) Envelope
Step 3: Parameter Uncertainty
Probability Monte Miss 6DOF of Carlo Distance Clearance
Lockheed Martin Aeronautics Company 6 Flowfield Grid Studies
Standard Grid: Extensive grid used for flowfield analysis
Tilt and Slant Sweeps Z Sweep to 25ft or WT limits Combined pitch and yaw displacements
Snowman Grid: New Grid design for improved accuracy and test efficiency
Large Snowman ~170 Points (ZC and YC, combined pitch and yaw)
Central Snowman ~18 Points (ZC, combined pitch and yaw)
Lockheed Martin Aeronautics Company 7 Flowfield Grid Studies
Sta.8 1KJDAM, Transonic Low Altitude Case
DX (in) DY (in)
Central Snowman
Large Snowman 10 feet ZC (in) CTS
Standard Grid CTS Trajectory Central Snowman Large Snowman Standard Grid Majority of cases have Minimal Effects on Trajectories near the AC Roll (deg) Pitch (deg) Yaw (deg)
10 feet 10 feet ZC (in)
Snowman grids transition to a nominal z-sweep between 5-6 ft
Lockheed Martin Aeronautics Company 8 In-Bay Aerodynamic Loads Modeling
• Vacuum Data taken at various vertical – In-bay aero set to zero from positions and pitch displacements carriage to park • Interp to Zero – In-bay aero interpolated from ΔZ Position park loads to zero at carriage (similar to CTS) • Interp to Carriage ΔΘ Position – In-bay aero interpolated from STOVL St.8:GBU-32 / St.7:AIM-120C park loads to carriage loads
• In-Bay Loads – In-bay aero obtained from an attached loads database
Lockheed Martin Aeronautics Company 9 In-Bay Aerodynamic Loads Modeling
Sta.8 1KJDAM, Transonic Low Altitude Case
DX (in) DY (in)
Attached Loads 10 feet ZC (in) Vacuum Interp to Zero
Interp to Carriage Attached Loads Interp to Carriage Interp to Zero Vacuum Roll (deg) Pitch (deg) Yaw (deg)
10 feet 10 feet ZC (in)
Lockheed Martin Aeronautics Company 10 In-Bay Aerodynamic Loads Modeling
Vacuum Interp to Carriage MinimalMinimal EffectsEffects onon Trajectories,Trajectories, MissMiss DistanceDistance Plots,Plots, ZC andand ClearanceClearance EnvelopesEnvelopes
Interp to Zero Attached Loads Vacuum Model Interp to Carriage
Miss Distance
• Recommendations Interp to Zero Attached Loads – Use attached loads data, if available – Interpolate from park loads to zero • Leverage modeling/simulation to reduce cost • No additional attached loads WT testing planned Lockheed Martin Aeronautics Company 11 JSF Store Separation 3-Step Process
Step 1: Validation Grid Data N 6DOF GEMD+ GEMD Database =CTS Traj? 6DOF (ADAMS) Y OK
Grid Data N =CTS Aero? Y
Step 2: Flight Envelope
6DOF Miss Flight Distance Clearance (M,Alt) Envelope
Step 3: Parameter Uncertainty
Probability Monte Miss 6DOF of Carlo Distance Clearance
Lockheed Martin Aeronautics Company 12 Flight Clearance Envelope
• ASEP High Fidelity Tool –ADAMS (Automatic Dynamic Analysis of Mechanical Systems) – ASEP (ADAMS Store Separation - customized VI-AirCraft)
• Flight Envelope Simulations
Lockheed Martin Aeronautics Company 13 ASEP Subsystem-based Approach
Subsystems Assemblies Simulations
• component Wheel(s) Wheel Wheel/Tire
LGR • subsystem LGR Structure Steady Axle Load Brakes (w/o wheels) • subsystem Hydraulics Drop Retract-Extend Control Laws LGR Dynamics (w/ wheels) • full vehicle Engine •Dyn. Tipback •Landing •Taxi & Shimmy •Catapult Airframe Full Aircraft •Braking •In-flight
• full vehicle stores Stores Full Aircraft Stores •StoreMotion •Simulation •Basic In-flight •Basic In-flight •Full maneuver •Full maneuver •Pit ejection
Lockheed Martin Aeronautics Company 14 ASEP Workflow
Tests Post- Components Templates Subsystems Assemblies (Simulations) Processing •parts & joints •oleo •actuators •aero •user-forces •etc.
Standard Existing Existing or New Existing or New Existing Existing or New User
Template Existing New Builder
Customizer New Types New Types New Types New Types New Types New Types
Lockheed Martin Aeronautics Company 15 ASEP Templates
Flexible Parts: (from NASTRAN / ANSYS) Pistons Swaybraces Flexible Connections: Airframe attachments Releasable lugs Swaybrace pads Piston/Housing bearings Friction: Piston/Housing bearings Swaybrace pads Freeplay: Piston/Housing bearings
Lockheed Martin Aeronautics Company 16 ASEP Workflow
Tests Post- Components Templates Subsystems Assemblies (Simulations) Processing •parts & joints •oleo •actuators •aero •user-forces •etc.
Standard Existing Existing or New Existing or New Existing Existing or New User
Template Existing New Builder
Customizer New Types New Types New Types New Types New Types New Types
Lockheed Martin Aeronautics Company 17 Library of Subsystems
Lockheed Martin Aeronautics Company 18 Create Assemblies from Subsystems
Library of Subsystems Select subsystems during assembly creation process Stores Subsystem e ram Airf ear g G n din Store Assembly Only ylo Stores Subsystem Lan P r cto Eje s tem k s RFull-aircraftac Assembly ubsy ual r S D the or Airframe Subsystem O ect t Ej Lef mb Bo t ig rcraf st r l-ai Te Ful ver neu Ma
Lockheed Martin Aeronautics Company 19 Assembly & Automated Simulation
• Comprised of rigid and/or flexible subsystems • Ready for automated landing gear and/or store-related simulations
Lockheed Martin Aeronautics Company 20 PostProcessing Simulation Results
Lockheed Martin Aeronautics Company 21 JDAM Flight Envelope Simulations
• Miss distances are automatically computed in ASEP’s post-processor • Need to perform 100+ simulations for each flight envelope – Repeat the envelope for: • Various G’s • Various +/- Roll rates • Flex/Freeplay, when necessary • Various adjacent stores
Lockheed Martin Aeronautics Company 22 STOVL (2) GBU-32 MK-83 JDAM (I) + (2) AIM-120C (I)
Basis for Assessment • CTS: WS-15 data • Freestream: Boeing large (~1/3) scale • In-Bay Loads: WS-15 Attached Loads • Flowfield: WS-15 • CFD: na • 6DOF: ADAMS (Rigid, no freeplay)
Lockheed Martin Aeronautics Company 23 STOVL GBU-32 Envelope 0.5g, All Rigid, No Freeplay, 0°/sec Roll Rate
Trajectory
DX (in) DY (in) Time
ZC (in) Flight Clearance Envelope
Roll (deg) Pitch (deg) Yaw (deg)
Miss ZC (in)
Miss Distance
Lockheed Martin Aeronautics Company 24 STOVL GBU-32 Envelope 0.5g, All Rigid, No Freeplay, 25°/sec Roll Rate
Trajectory
DX (in) DY (in) Time
ZC (in) Flight Clearance Envelope
Roll (deg) Pitch (deg) Yaw (deg)
Miss
(No mi nal) ZC (in)
Miss Distance
Lockheed Martin Aeronautics Company 25 Sample Ejector Mech. Differences
• Moving vs. Non-moving swaybraces • Same ejector piston force, aero database, store, maneuver
Lockheed Martin Aeronautics Company 26 Sample Flexible Simulations
• Launcher Rail, Aircraft Wing, BRU Attachments, etc.
Lockheed Martin Aeronautics Company 27 JSF Affordability is Key
• Fewer store sep flight test points • Increased number of aircraft/stores to certify
• Therefore, –Increased emphasis on: • Modeling & simulation • Validation • Efficiency –Pre-flight analysis is critical!
Lockheed Martin Aeronautics Company 28 What’s New & Different?
• Flowfield Grid Studies - Uses for the Central Snowman – Exploratory studies to capture separation characteristics – Candidate as a CFD grid • In-Bay Aerodynamic Loads Modeling – Minimal trajectory and miss distance effects – Use aerodynamic model to reduce testing costs • Innovative Database Building and 6DOF Tool – Streamline process for building databases – Techniques provide good basis for validating aerodynamic databases and 6DOF analysis • ASEP 6DOF Tool – Automation/speed, different user modes, higher fidelity – Quick integration of aero and autopilot modules
Lockheed Martin Aeronautics Company 29 QUESTIONS?QUESTIONS?
Lockheed Martin Aeronautics Company 30 BackupBackup
Lockheed Martin Aeronautics Company 31 Database Validation Techniques
• Flowfield Grid Studies • In-Bay Aerodynamic Loads Modeling • Innovative Tools for Database Building and Validation – GEMD (General Exchange of Methods and Data) – Automated Database Building Scripts – Wind-tunnel CTS* vs. Database Aerodynamics – Wind-tunnel CTS* vs. Database Trajectories
* CTS – Captive Trajectory System Lockheed Martin Aeronautics Company 32 Flowfield Grid Studies
Standard Grid: Extensive grid used for flowfield analysis
Tilt and Slant Sweeps Taguchi Z-SweepMethodZ-Sweep: Assess grid Z Sweep to 25ft or WT limits interpolationCollection errors and define Combined pitch and yaw displacements Collection uncertaintiesMethodMethod in database
Snowman Grid: New Grid design for improved accuracy and test efficiency
Large Snowman ~170 Points (ZC and YC, DiscreteDiscrete PointsPoints combined pitch and yaw) CollectedCollected likelike Taguchi:“Pitch-Pause”“Pitch-Pause” 18 Select Points Central Snowman ~18 Points MethodMethod (ZC, combined pitch and yaw)
Lockheed Martin Aeronautics Company 33 Flowfield Grid Studies
• Wind-tunnel test efficiencies ~ “X” time units - Standard Grid ~ “X”×2 time units - Large Snowman ~ “X”÷2 time units - Central Snowman
• Central Snowman Pros/Cons + Reasonable comparisons with CTS – Discrete data points vs. sweeps • Less efficient for comparable amounts of data • Relies on linear interpolation in key locations
• Use the Central Snowman grid for exploratory cases and CFD • Prediction errors used in uncertainty analysis
Lockheed Martin Aeronautics Company 34 Flowfield Grid Studies
Standard Grid: Extensive grid used for • Measured points used to: flowfield analysis – Assess interpolation errors between grid collection methods Tilt and Slant Sweeps Taguchi Method: Assess grid – Incorporate into uncertainty analysis Z Sweep to 25ft or WT limits interpolation errors and define Combined pitch and yaw displacements (Step 3 in the Process) uncertainties in database • Consider 3-levels of each parameter, uniformly spaced Snowman Grid: New Grid design for improved accuracy and test efficiency 30” from Carriage 48” from Carriage • ΔXp = -2, 0, 2 in • ΔXp = -5, 0, 5 in Large Snowman • ΔYp = -2, 0, 2 in • ΔYp = -4, 0, 4 in ~170 Points (ZC and YC, • ΔZp = 25, 30, 35 in • ΔZp = 43, 48, 53 in combined pitch and yaw) • ΔΨ = -3, 0, 3 deg • ΔΨ = -5, 0, 5 deg • ΔΘ = -5, 0, 5 deg • ΔΘ = -10, 0, 10 deg • ΔΦ = -10,Taguchi: 0, 10 deg 18 Select• ΔΦ Points= -20, 0, 20 deg Central Snowman ~18 Points • Full Factorial = 36 = 729 Cases (ZC, combined pitch and yaw) • Taguchi L18 Array to Select 18 Cases
Lockheed Martin Aeronautics Company 35 Flowfield Grid Studies
Sta.8 GBU-32 (1KJDAM) Error = Measured minus Predicted Data Snowman vs. Standard Grids 0.25 produce similar error bands 0.2 Large Snowman Standard Grid 0.15 Some error reduction for 0.1 Large Snowman 0.05
0
-0.05
-0.1
-0.15 DCN Taguchi -DCN Taguchi Grid Data -0.2 Central Snowman -0.25
-0.3 0 5 10 15 20 25 30 35 40 Point
Step 3: Uncertainty Bands Monte Carlo Uncertainty Analysis
Lockheed Martin Aeronautics Company 36 Database Validation Techniques
• Flowfield Grid Studies • In-Bay Aerodynamic Loads Modeling • Innovative Tools for Database Building and Validation – GEMD (General Exchange of Methods and Data) – Automated Database Building Scripts – Wind-tunnel CTS vs. Database Aerodynamics – Wind-tunnel CTS vs. Database Trajectories
Lockheed Martin Aeronautics Company 37 Database Validation Techniques
• Flowfield Grid Studies • In-Bay Aerodynamic Loads Modeling • Innovative Tools for Database Building and Validation – GEMD (General Exchange of Methods and Data) – Automated Database Building Scripts – Wind-tunnel CTS vs. Database Aerodynamics – Wind-tunnel CTS vs. Database Trajectories
Lockheed Martin Aeronautics Company 38 Innovative Database Building Tools
TemplatesTemplates ofof AerodynamicAerodynamic DatabaseDatabase DatabaseDatabase FunctionsFunctions inin GEMDGEMD (General(General ExchangeExchange ofof MethodsMethods && Data)Data) DatabaseDatabase ScriptingScripting ToolTool (dBST)(dBST) AutomatedAutomated ScriptsScripts forfor Generating/ValidatingGenerating/Validating DatabasesDatabases “Black“Black Box”Box” Object Object
Wind-TunnelWind-Tunnel DataData FilesFiles GBU-32GBU-32 CTSCTS TrajectoryTrajectory AeroAero
What effects do these(ft) differences have(ft) on trajectories?(ft) GBU-32GBU-32 AeroAero ExtractedExtracted fromfrom thethe DatabaseDatabase
Lockheed Martin Aeronautics Company 39 (ft) (ft) (ft) 6DOF Analysis and Validation
Sta.8 1KJDAM, Transonic Low Altitude Case
DX (in) DY (in)
ADAMS with Database Aero 10 feet ZC (in) CTS Run ADAMS with CTS Aero CTS Run ADAMS w/ CTS Aero ADAMS w/ Database Aero Roll (deg) Pitch (deg) Yaw (deg) No ejector modeling CTS motion to EOS 10 feet 10 feet √ StoreZC (in) 6DOF validation √ Database validation
Lockheed Martin Aeronautics Company 40