Langford Analytic · Knowledge Base
Design Checklists
Concise engineering checks for review, verification and technical sign-off — FEA review, static strength, joints, fatigue, dynamics, buckling, composites, thermal, loads, materials, welds, design optimisation, verification and validation, and reporting.
FEA Review
Linear Static FEA Review ChecklistReview prompts for linear static FE models — geometry, mesh, boundary conditions, loads, material, results and verification before acceptance.Nonlinear FEA Review ChecklistReview prompts for nonlinear FE models — nonlinearity justification, convergence, load stepping, contact, plasticity and equilibrium path interpretation.Contact Analysis Review ChecklistReview prompts for contact modelling — formulation, stiffness, friction, penetration, convergence and contact status verification.Mesh Quality Review ChecklistReview prompts for mesh quality — element type, aspect ratio, distortion, transitions, through-thickness elements and convergence evidence.Boundary Condition Review ChecklistReview prompts for boundary conditions — physical restraint representation, over-constraint, under-constraint, symmetry and rigid-body modes.Load Application Review ChecklistReview prompts for load application — physical load paths, distributed versus point loads, bearing loads, inertial loads and load verification.FE Model Verification ChecklistReview prompts for FE model verification — reactions, hand calculations, mesh convergence, limiting cases, sensitivity and singularity checks.FE Model Validation ChecklistReview prompts for model validation against test data — strain-gauge correlation, modal correlation, measurement uncertainty and acceptance criteria.FEA Reporting ChecklistReview prompts for FEA report content — model description, assumptions, convergence, verification, results, limitations and sign-off.
Static Strength
Static Strength Assessment ChecklistReview prompts for static strength assessment — load cases, stress extraction, allowables, margins of safety and failure mode coverage.Margin of Safety Review ChecklistReview prompts for margin of safety calculations — allowable selection, applied stress definition, interaction methods and sign-off.Combined Stress Review ChecklistReview prompts for combined stress assessment — interaction equations, von Mises versus principal stress, and multi-axial loading checks.Bearing and Net-Section Review ChecklistReview prompts for bearing and net-section checks at fastener holes — edge margin, bypass stress and bearing–bypass interaction.Local Stress Concentration Review ChecklistReview prompts for stress concentration assessment — Kt source, FE singularity check, notch sensitivity and fatigue implications.
Joints & Interfaces
Bolted Joint Analysis ChecklistReview prompts for bolted joint analysis — preload, load distribution, bearing, bypass, separation, fastener strength and joint flexibility.Bolt Preload ChecklistReview prompts for bolt preload specification, application and verification — torque–tension relationship, relaxation and sensitivity.Joint Separation ChecklistReview prompts for joint separation analysis — limit load gapping, contact nonlinearity, friction capacity and slip-critical assessment.Pin and Lug Joint ChecklistReview prompts for pin and lug joint analysis — bearing, shear, tear-out, net-section and pin bending.Bonded Joint ChecklistReview prompts for bonded joint analysis — surface preparation, peel stress, shear stress distribution, overlap length and environmental degradation.Joint Model Verification ChecklistReview prompts for verifying FE models of joints — fastener load distribution, contact status, preload balance and correlation with hand calculations.
Fatigue & Damage Tolerance
S-N Fatigue Assessment ChecklistReview prompts for S-N fatigue analysis — stress definition, S-N curve source, mean stress correction, surface finish and scatter factor.Variable-Amplitude Fatigue ChecklistReview prompts for variable-amplitude fatigue — spectrum definition, cycle counting, mean stress treatment and sequence effects.Mean Stress Correction ChecklistReview prompts for mean stress correction — Goodman, Gerber, Soderberg selection and application to S-N fatigue.Fatigue Hot-Spot Review ChecklistReview prompts for identifying and assessing fatigue-critical locations — stress concentrations, surface finish, fretting and corrosion fatigue.Damage-Tolerance Assessment ChecklistReview prompts for damage-tolerance assessment — initial flaw size, crack growth, residual strength, inspection threshold and interval.Fracture Mechanics Review ChecklistReview prompts for fracture mechanics analysis — stress intensity factor, toughness, geometry factor and failure assessment diagram.
Dynamics & Vibration
Modal Analysis Review ChecklistReview prompts for modal analysis — mass representation, mode extraction range, effective mass, rigid-body modes and boundary conditions.Frequency Response Analysis ChecklistReview prompts for frequency response analysis — damping, frequency resolution, mode participation and peak response interpretation.Random Vibration Analysis ChecklistReview prompts for random vibration analysis — PSD input, mass participation, damping, frequency resolution and 3σ response interpretation.Shock Response Spectrum ChecklistReview prompts for shock response spectrum analysis — SRS input, modal truncation, damping and peak response interpretation.Damping Assumption Review ChecklistReview prompts for damping assumptions — source, value, type (viscous, structural, modal) and sensitivity to response amplitude.
Buckling & Stability
Eigenvalue Buckling Review ChecklistReview prompts for eigenvalue buckling analysis — load factor interpretation, mode shape, imperfection sensitivity and follow-up nonlinear analysis.Nonlinear Buckling Design Review ChecklistReview prompts for nonlinear collapse analysis — imperfection, material nonlinearity, load stepping and limit-point interpretation.Imperfection Sensitivity ChecklistReview prompts for assessing imperfection sensitivity — imperfection shape, magnitude, knockdown factors and collapse load sensitivity.Column Buckling ChecklistStructured checklist for column buckling assessment — geometry, slenderness, end conditions, analysis method, margins and verification.Plate Buckling ChecklistChecklist for plate buckling assessment — geometry, loading, boundary conditions, critical stress, post-buckling and margins.Shell Buckling ChecklistChecklist for shell buckling assessment — geometry, R/t ratio, loading, imperfection sensitivity, analysis method and collapse prediction.Stiffened Panel Buckling ChecklistChecklist for stiffened panel buckling — skin buckling, stiffener stability, crippling, post-buckling reserve and collapse.Nonlinear Buckling FEA Setup & Verification ChecklistChecklist for nonlinear buckling FEA — imperfections, material, solver settings, convergence, collapse and verification.Buckling Analysis Review ChecklistComprehensive review checklist for buckling analysis reports — loads, model, method, imperfections, results, margins and conclusions.
Composites
Composite Laminate Definition ChecklistReview prompts for composite laminate definition — symmetry, balance, ply percentages, consecutive ply limit and ply drop-off strategy.Composite FEA Review ChecklistReview prompts for composite FEA — material orientation, shell normal, ply stack, failure indices, interlaminar stress and through-thickness limitations.Ply Orientation ChecklistReview prompts for ply orientation verification — fibre direction, shell normal, coordinate system and drawing cross-reference.Composite Failure Criteria Application & Review ChecklistReview prompts for composite failure criteria selection and application — fibre vs matrix, first-ply vs last-ply, and allowables.Composite Joint ChecklistReview prompts for composite joints — bearing, bypass, pull-through, fastener selection and bonded joint peel stress.Ply Drop-Off Review ChecklistReview prompts for ply drop-off design and analysis — drop gradient, interlaminar stress, manufacturing feasibility and inspection.
Thermal & Thermal-Stress
Thermal Analysis Review ChecklistReview prompts for thermal analysis — boundary conditions, material properties, mesh, contact resistance and steady-state versus transient.Thermal-Stress Analysis ChecklistReview prompts for thermal-stress analysis — temperature field transfer, constrained expansion, material properties and stress interpretation.Thermal Boundary Condition ChecklistReview prompts for thermal boundary conditions — convection, radiation, contact resistance, ambient temperature and heat flux application.
Loads & Load Cases
Load Definition ChecklistReview prompts for load definition — source, magnitude, direction, distribution, units and traceability to the operating environment.Free-Body Diagram ChecklistReview prompts for free-body diagrams — equilibrium, force directions, reaction points and completeness.Load Path ChecklistReview prompts for load path analysis — continuity, load introduction, shear flow and structural topology.Load Combination ChecklistReview prompts for load combinations and envelopes — factors, superposition, critical case identification and limit versus ultimate.Load Verification ChecklistReview prompts for verifying applied loads — reactions, equilibrium, mass properties and traceability from source to applied load.
Materials
Material Data Review ChecklistReview prompts for material data — source, grade, temper, product form, orientation, temperature, allowables versus typical and units.Allowables Review ChecklistReview prompts for design allowables — basis (A, B, S), statistical treatment, environmental knockdown and application to strength checks.Plasticity Model ChecklistReview prompts for plasticity models — true stress-strain, hardening type, yield criterion, calibration and extrapolation.
Welds
Weld Static Strength ChecklistReview prompts for weld static strength — throat thickness, weld length, stress type and allowable source.Weld Fatigue ChecklistReview prompts for weld fatigue — detail class, stress definition (nominal, hot-spot, notch), S-N curve and cumulative damage.Weld FEA Modelling ChecklistReview prompts for modelling welds in FEA — representation, mesh, stress extraction location and modelling approach selection.Weld Detail Review ChecklistReview prompts for weld detail design — access, inspectability, weld sequence, distortion control and drawing specification.
Design & Optimisation
Structural Design Review ChecklistReview prompts for structural design — load path clarity, failure mode coverage, manufacturability, inspectability and certification evidence.Weight Optimisation ChecklistReview prompts for weight optimisation — objective, constraints, manufacturability, robustness and margin preservation.Topology Optimisation Review ChecklistReview prompts for topology optimisation — objective, constraints, load cases, manufacturing constraints and interpretation of results.
Verification & Validation
Hand Calculation Correlation ChecklistReview prompts for comparing FE results with hand calculations — location, stress definition, assumptions and tolerance.Strain-Gauge Correlation ChecklistReview prompts for strain-gauge correlation with FE — gauge location, orientation, integration length, load scaling and uncertainty.Modal Test Correlation ChecklistReview prompts for modal test correlation — frequency comparison, MAC, boundary conditions and test setup.Sensitivity Study ChecklistReview prompts for sensitivity studies — parameter selection, range justification, ranking and documentation.
Reporting & Technical Review
Stress Report ChecklistReview prompts for stress report content — loads, geometry, material, analysis method, results, margins, assumptions and sign-off.Independent Review ChecklistReview prompts for independent technical review — what a checker should verify before signing off an analysis.Assumption Register ChecklistReview prompts for assumption registers — completeness, traceability, conservatism and impact assessment.Technical Sign-Off ChecklistReview prompts for technical sign-off — evidence chain, verification, validation, margins and independent review.
Seismic
Seismic FEA Model ChecklistA comprehensive checklist for verifying finite element models used in seismic analysis, covering mass distribution, boundary conditions, element selection and dynamic formulation before any modal or response-spectrum run is accepted.Response Spectrum Analysis ChecklistA checklist for verifying response spectrum analysis runs, covering spectrum input, modal extraction, participation checks, modal combination method selection and directional combination.Floor Response Spectrum Input ChecklistA checklist for verifying floor response spectrum data before it is used as input to equipment seismic analysis, covering elevation, damping, frequency range, interpolation and provenance.Modal Mass Participation ChecklistA checklist for verifying modal mass participation and effective modal mass results, ensuring sufficient modes have been extracted and the cumulative participation meets the required threshold.Cabinet Seismic Assessment ChecklistA checklist for the seismic assessment of electrical and control cabinets, covering natural frequency, anchorage, internal equipment, panel stiffness, sliding and overturning.Seismic Anchorage ChecklistA checklist for the design and verification of seismic anchorage systems, covering anchor selection, capacity, baseplate flexibility, edge effects, prying action and load combinations.Shake-Table Qualification ChecklistA checklist for planning and executing shake-table qualification testing, covering test specification, input motion, instrumentation, acceptance criteria and reporting.Seismic Analysis Review ChecklistA checklist for the technical review of seismic analysis results before they are used for design decisions, covering model validity, result plausibility, combination correctness and documentation completeness.Seismic Qualification Report ChecklistA checklist for the content and structure of a seismic qualification report, ensuring all required information is presented for review and acceptance by the certifying authority.
Turbomachinery
Turbomachinery Structural Analysis ChecklistComprehensive checklist for turbomachinery structural analysis — requirements, loads, models, assessment, verification and reporting.Turbine Blade Analysis ChecklistChecklist for turbine blade structural analysis covering loads, stress, dynamics, fatigue, creep and clearance.Turbine Disc Analysis ChecklistChecklist for turbine disc structural analysis covering bore stress, rim load, thermal stress, fatigue and creep.Blade Root Contact ChecklistChecklist for blade root contact analysis covering model, contact definition, verification and fretting.Turbomachinery Modal Analysis ChecklistChecklist for turbomachinery modal analysis covering pre-stress, frequencies, Campbell diagram and resonance assessment.Overspeed Assessment ChecklistChecklist for turbomachinery overspeed analysis covering material, nonlinear FEA, clearance and margin.Blade-Off Assessment ChecklistChecklist for blade-off structural and containment assessment covering imbalance, casing response and containment.Turbomachinery Analysis Review ChecklistChecklist for independent review of turbomachinery structural analysis reports.
Pressure & Containment
Pressure Analysis Input ChecklistChecklist of inputs required for a pressure and containment analysis — pressure, temperature, geometry, material, loads and standards.Internal Pressure Assessment ChecklistChecklist for internal pressure structural assessment — membrane stress, discontinuity stress, nozzle loads, head stress, fatigue and margins.External Pressure Assessment ChecklistChecklist for external pressure buckling and collapse assessment — geometry, imperfection, analysis method, margin and verification.Pressure Vessel FEA ChecklistChecklist for pressure vessel FEA — model setup, element selection, mesh, loads, boundary conditions, material, solving and post-processing.Nozzle Analysis ChecklistChecklist for pressure vessel nozzle analysis — geometry, loads, FEA modelling, stress linearisation and margin assessment.Flanged Closure ChecklistChecklist for bolted flange closure assessment — pressure thrust, bolt load, gasket compression, flange rotation, leakage and fatigue.Pressure Piping Load ChecklistChecklist for pressure piping load assessment — pressure, thrust, supports, nozzle loads, thermal expansion and occasional loads.Pressure Buckling ChecklistChecklist for external pressure buckling assessment — eigenvalue analysis, nonlinear collapse, imperfections and margin.Pressure Model Verification ChecklistChecklist for verifying a pressure vessel FEA model — equilibrium, analytical comparison, mesh convergence, displacement and reporting.Pressure & Containment Analysis Review ChecklistFinal review checklist for a pressure and containment analysis — requirements, loads, model, verification, stress assessment, margins and reporting.
Probabilistic & Reliability
Probabilistic Analysis Input ChecklistA checklist for verifying probabilistic analysis inputs — distributions, parameters, correlation, bounds and documentation.Probability Distribution Selection ChecklistA checklist for verifying that the selected probability distributions are appropriate for each engineering variable.Monte Carlo Analysis ChecklistA checklist for verifying a Monte Carlo analysis — model verification, automation, convergence, failure count and result plausibility.Structural Reliability ChecklistA checklist for verifying a structural reliability assessment — limit states, method, reliability index, sensitivity and reporting.FORM Analysis ChecklistA checklist for verifying a FORM reliability analysis — transformation, design point, convergence, sensitivity factors and linearity check.Probabilistic Fatigue ChecklistA checklist for verifying a probabilistic fatigue analysis — S-N scatter, load uncertainty, life distribution and failure probability.Bayesian Updating ChecklistA checklist for verifying a Bayesian updating analysis — prior, likelihood, data, posterior and updated predictions.Reliability Analysis Review ChecklistA comprehensive checklist for reviewing a probabilistic reliability assessment — inputs, method, results, sensitivity, validation and reporting.
Ballistics & Penetration
High-Rate Impact Analysis ChecklistA checklist for verifying a high-rate impact analysis — inputs, model, material, contact, mesh and results.Impact Material-Data ChecklistA checklist for verifying material data used in impact FEA — sources, rate dependence, failure model and calibration.Explicit Impact FEA ChecklistA checklist for verifying an explicit FEA impact analysis — solver setup, time step, mass scaling, contact and stability.Penetration Mesh ChecklistA checklist for verifying the mesh in a penetration analysis — refinement, through-thickness, transitions and sensitivity.Energy-Balance ChecklistA checklist for verifying the energy balance in an explicit impact analysis.Composite Impact Damage Assessment ChecklistA checklist for verifying an impact analysis of composite structures — damage modes, delamination, hidden damage and residual strength.Impact Model Validation ChecklistA checklist for validating an impact FEA model against test data.Ballistic Structural Analysis Review ChecklistA comprehensive checklist for reviewing a ballistic impact structural analysis — from inputs through results to reporting.
Creep & High-Temperature
Creep Analysis ChecklistA checklist for verifying a creep analysis — relevance, material data, model, FEA setup, results and reporting.High-Temperature Material Data ChecklistA checklist for verifying material data used in high-temperature creep analysis.Creep FEA Model ChecklistA checklist for verifying a creep FEA model — mesh, boundary conditions, time stepping, convergence and outputs.Creep-Rupture Assessment ChecklistA checklist for verifying a creep rupture life assessment.Creep-Fatigue Review ChecklistA checklist for reviewing a creep-fatigue interaction assessment.
Random Vibration
Random Vibration Analysis Checklist — Domain ReferenceA comprehensive checklist for reviewing a complete random vibration analysis — from environment definition through to reporting.PSD Input ChecklistA checklist for verifying a PSD input specification before use in analysis or test.Modal Model ChecklistA checklist for verifying the modal model before running random vibration analysis.Random Response FEA ChecklistA checklist for verifying the random response solution and results.Random Vibration Fatigue ChecklistA checklist for verifying a random vibration fatigue assessment.Random Vibration Test ChecklistA checklist for planning and executing a random vibration qualification test.Analysis–Test Correlation ChecklistA checklist for correlating random vibration analysis with test data.
Shock & Transient Dynamics
Shock Analysis Input ChecklistConcise review checklist for shock-analysis inputs, units, axes, interface conditions, damping, bandwidth and acceptance requirements.Mechanical Shock FEA ChecklistConcise review checklist for mechanical-shock FEA model setup, transient controls, response recovery and verification.SRS Review ChecklistConcise review checklist for SRS definition, damping, frequency range, resolution, response convention and traceability.Pyroshock Assessment ChecklistConcise review checklist for pyroshock assessment, high-frequency modelling assumptions, bandwidth and evidence limitations.Drop Shock Analysis ChecklistConcise review checklist for drop-shock analysis, impact conditions, contact assumptions, response recovery and correlation.Shock Test ChecklistConcise review checklist for mechanical-shock testing, instrumentation, filtering, fixture/interface conditions and acceptance evidence.Shock Analysis–Test Correlation ChecklistConcise review checklist for shock analysis–test correlation using time histories, SRS, structural modes and uncertainty evidence.Shock Qualification Review ChecklistConcise review checklist for final shock qualification, requirements traceability, analysis/test evidence and technical sign-off.
Advanced Damage & Failure
Progressive Composite Damage ChecklistA checklist for reviewing a progressive composite damage analysis — model setup, parameters, solver, verification and reporting.Composite Failure Criterion Selection ChecklistA checklist for selecting and verifying a composite failure criterion.Delamination Analysis ChecklistA checklist for delamination analysis — method selection, parameters, interfaces and verification.Cohesive-Zone Modelling ChecklistA checklist for setting up and verifying cohesive-zone models for delamination or bonded joints.Composite Impact FEA ChecklistA checklist for composite impact FEA — model setup, damage, energy balance and verification.BVID Assessment ChecklistA checklist for assessing barely visible impact damage in composite structures.Compression-After-Impact ChecklistA checklist for CAI assessment — damage state, analysis, test correlation and residual strength.Advanced Composite Damage Review ChecklistA comprehensive checklist for reviewing an advanced composite damage analysis — from model setup through to reporting.