Roger Newby — Vehicle & Automotive Engineering

Interactive models — worked examples on published data

See the analysis working. Thirty seconds each.

What you're looking at: live engineering models — the same class of analysis behind my expert reports — each built on published, independently measured data and each stating its validation record. Move the controls; the physics responds. This is the working method, shown rather than claimed.

1 · Offset collision — why struck cars spin

Plan view — side impact with offset

Inputs

Bullet vehicle speed 30 mph Target vehicle speed 10 mph Impact offset from target CG 1.2 m Bullet : target mass ratio 1.3

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Target ΔV

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Target yaw rate

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Bullet ΔV

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Energy to crush

momentumangular momentumenergy ≥ 0

Impulse mechanics of this class reproduced an instrumented staged collision (IPTM 2018; arXiv:2001.03165) — measured yaw matched to 0.5%. Worked example on public data, not casework.

2 · How small can a fatal crack be?

A component fails "without warning". Fracture mechanics says how big the hidden flaw needed to be.

Crack depth 2.5 mm Material & condition

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Stress to break it

The 1967 Silver Bridge collapse — 46 deaths — began at a crack 2.5 mm deep. This calculator reproduces the official finding. σ = K/√(πa), edge crack.

3 · Same speed, different outcome

Injury severity follows stopping distance, not speed alone — why "it was only 30 mph" answers nothing.

Impact speed 30 mph Crush / stopping distance 0.5 m

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Mean deceleration

a = v²/2s. The order-of-magnitude spread from one uncertain input is why honest reports state ranges, never single numbers.

4 · Speed from skid marks

The oldest tool in collision work: tyre marks record a minimum speed — and the surface decides how much.

Skid mark length 20 m Road surface

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Minimum speed at start of skid

v = √(2μgs), locked-wheel model — a minimum: energy already lost to impact or yaw is on top. Range shown reflects the honest surface uncertainty.

5 · Corrosion — the quiet stress multiplier

A component doesn't need to look bad to be dangerous: lost wall thickness raises stress faster than it looks.

Wall thickness lost to corrosion 10 % Pitting present?

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Stress vs as-new, same load

Box-section bending model — accounts for section-loss from all four walls (stress rises as the square of fractional loss, making this conservatively predictive). Pits add a local stress concentration on top — the fatigue-initiation mechanism behind many "sudden" failures.

6 · Does the mesh converge? — FE vs exact for a tapered beam

A cantilever beam in steel or aluminium, tapered from root to tip. Three answers compared: the hand formula (uniform-beam assumption — the class of calculation behind a desktop assessment), the finite-element solution (beam elements, each using averaged section properties), and the exact analytical integration (the reference standard a commercial code converges toward).

Number of elements 4 Taper — tip depth as % of root 50% Material

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Hand formula

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FE solution

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Exact (ref.)

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Hand error

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FE error

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Free DOF

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Root bending stress (σ = Mc/I)

Euler-Bernoulli beam elements (cubic Hermite shape functions, 2 DOF per node). Each element uses the second moment of area at its midpoint — the taper is the simplification the mesh resolves. Fixed end: v = θ = 0. Tip load P = 10 kN on a 1 m span, 50 mm wide. The 0.03% structural accuracy in the validation table below (Section 7) is a problem of this class.

7 · How I check my own work

The audit that refused a pretty answer.

Validating a crash simulation this year, the deformed shape matched a laboratory experiment to within 2% — a result most would publish. The energy audit didn't pass: the books said 140% of the energy was accounted for, which is physically impossible. The run was declared invalid, the fault traced (a contact algorithm quietly injecting energy), fixed, and re-run — energy balanced to 99.6%, shape still within 2%.

Every analysis I produce carries its audits: momentum, energy, sanity checks against known physics, and a source for every input. A result that fails its audit is not softened — it is stopped. That is what an opinion needs behind it before it enters a courtroom.

Method	Tested against	Demonstrated accuracy
Structural stress analysis	Commercial FEA benchmark (ANSYS)	0.03% / ~1%
High-speed impact simulation	Physical gas-gun experiment	<2%; energy 99.6%
Vehicle collision (ΔV & yaw)	Instrumented staged crash (2018)	yaw 0.5%; ΔV brackets truth
Fracture screening	Silver Bridge investigation (NTSB/NBS)	Reproduces official finding
FE mesh convergence	Exact tapered-beam integration (Model 6)	Converges to <0.1%; hand formula error quantified

Full validation dossier, with sources and data links, available on request.

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Services

Desktop-first. Fixed fees. Fast turnaround.

Collision damage analysis and vehicle assessment — the core of a high-volume paper practice. UK-wide coverage, desktop-first for speed and cost. CPR Part 35 expert reports and desktop analysis at fixed fees agreed before instruction.

Front-end collision damage showing crumpled bonnet and displaced bumper — vehicle damage consistent with moderate-speed frontal impact — Collision damage causation: is the damage consistent with the described accident?

Collision damage causation

Is the claimed damage consistent with the described accident? The question behind most RTA instructions — damage causation analysis, consistency checks, and evidential assessment. Identification of staged, fraudulent and exaggerated claims; insurance fraud investigation.

Vehicle damage assessment

Structured vehicle appraisal with photographic evidence capture — my daily professional practice. Condition reporting, defect identification, pre-existing damage analysis.

Valuations & write-off assessment

Pre-accident valuations, diminution in value, total-loss and write-off assessment, salvage categorisation (Category S and Category N assessment), reasonable repair periods, post-repair inspection, and repair quality disputes.

Vehicle quality & rejection disputes

Satisfactory quality, fitness for purpose, and durability under the Consumer Rights Act 2015. Vehicle rejection disputes, warranty disputes, inherent defects and vehicle defect analysis.

Collision severity screening

Delta-V, momentum and rotation analysis; consistency checks of accounts against physics. FEA-supported severity assessment validated against physical crash testing.

Credit hire

Vehicle suitability, hire period reasonableness, and rate challenges — engineering assessment supporting credit hire disputes.

Report reviews for advocates

Line-by-line review of opposing expert reports and drafting of cross-examination material — engineering analysis with legal training behind it.

Component failure screening

Fracture, fatigue and corrosion of vehicle and mechanical components — what broke first, what evidence would prove it, what to preserve.

Mediation

Civil & commercial mediation of technical, vehicle and transport disputes, via Newby Dispute Resolution.

Close-up of vehicle side panel damage and paint transfer from vehicle-to-vehicle contact — damage consistency analysis — Damage consistency: paint transfer patterns and deformation profiles tell the story of the impact.

Fees

Fixed. In writing. Before work starts.

Service	Fee
Desktop expert report (standard turnaround, ~10 working days)	Quoted per instruction
Priority report (expedited turnaround)	Quoted per instruction
Express report (fast-track delivery)	Quoted per instruction
Emergency 24-hour report	Quoted per instruction
On-site vehicle inspection (UK-wide, including travel)	Quoted per instruction
International on-site inspection (UAE, Middle East, Europe)	Quoted per instruction
Free ten-minute case call — no obligation	Free

All fees fixed, in writing, and agreed before work starts. No hourly-rate surprises. The fee reflects the complexity and scope of the instruction.
Competitive with industry standards and appropriate to the complexity of the instruction. Fees are structured to be proportionate — including within small-claims court-recoverable limits where applicable.
Tiered turnaround. Standard, priority, express, and emergency options to match your deadline. Desktop-first reports keep costs proportionate; on-site inspections available UK-wide and internationally where the evidence requires it.
Bespoke and complex instructions — multi-vehicle collisions, extensive evidence bundles, cases requiring detailed FEA or simulation work, or international inspections — are quoted individually.
Never outcome-related. Fees are payable regardless of result — the independence your report's declaration promises the court.
Team-backed delivery. A support network of paralegal and technical resource ensures capacity even on the tightest deadlines. All case materials handled on secure, encrypted platforms.
Written terms of engagement with every instruction. Single Joint Expert appointments welcome.
Professionally insured. Professional indemnity cover of £2,000,000. Certificate of insurance provided with terms of engagement on request.

Get in touch for a quote tailored to your instruction — no obligation.

Frequently asked questions

What solicitors and clerks usually ask first.

What types of cases do you handle?

Collision damage causation and consistency analysis, vehicle damage assessment, pre-accident valuations and write-off assessment, salvage categorisation, vehicle quality and vehicle rejection disputes (Consumer Rights Act 2015, inherent defects, vehicle defect analysis), insurance fraud investigation, credit hire, collision severity screening, post-repair inspections, component failure (fracture, fatigue, corrosion), vehicle structures analysis, and report reviews with cross-examination material for advocates.

What does a CPR Part 35 report include?

A full, fixed-fee, desktop-first analysis covering the engineering question — damage causation, collision severity, vehicle condition, or component failure. Every report includes a statement of truth, a declaration of independence, and the validation record behind each method used. The report is yours to disclose or not; the fee is the same either way.

How quickly can you turn a report around?

Standard reports are typically returned within ten working days. Priority and express options are available for tighter deadlines, and emergency 24-hour turnaround can be arranged with the full support team committed to your instruction. Use the deadline field in the enquiry form below.

How much does a report cost?

Fees are competitive with industry standards and proportionate to the complexity of the instruction — including within small-claims court-recoverable limits where applicable. Standard, priority, express, and emergency turnaround tiers are available. Bespoke or complex instructions — multi-vehicle cases, simulation work, or on-site inspections — are quoted individually. All fees are fixed, in writing, and agreed before work starts. Send an enquiry or book a free case call for a quote.

Can you act as a Single Joint Expert?

Yes. SJE appointments are welcome. The same independence, the same methods, the same fixed fees. Written terms of engagement with every instruction.

What if there is already an opposing expert report?

I review opposing reports line by line — checking the methodology, the assumptions, and whether the calculations reproduce. The output is a structured critique with cross-examination questions your advocate can use directly.

What area do you cover?

UK-wide, desktop-first — expert reports and desktop analysis need no travel. On-site vehicle inspections arranged anywhere in the UK where the evidence requires it. International instructions accepted, with particular experience in the UAE and wider Middle East (ten years' regional experience; conversational Arabic). European and other international inspections arranged on request.

Are you insured?

Professional indemnity cover of £2,000,000. Certificate of insurance provided with terms of engagement on request. Registered with the ICO as a data controller.

Send an enquiry

About

Roger Newby AMIMechE

Vehicle and automotive engineering consultant specialising in collision damage analysis, vehicle damage assessment, condition reporting, and valuation disputes. Current daily professional practice in structured vehicle appraisal and damage inspection using formal evidential protocols with photographic reporting. Listed on the APIL Expert Witness Directory and the UK Register of Expert Witnesses.

BSc (Hons) Motorsport Technology (University of Hertfordshire); postgraduate crash-structures research at Cranfield University — experimental testing and finite-element modelling of automotive crash structures and vehicle structures (LS-DYNA, EPSRC-funded). Race-team experience in a championship-winning TVR Tuscan Challenge season. Legal training to Master's level (LLM, BPP); practising civil & commercial mediator. Associate Member, Institution of Mechanical Engineers. Ten years' professional experience in the UAE and Middle East; conversational Modern Standard Arabic.

Collision-damaged vehicle undergoing professional inspection — structural deformation assessment and crash damage analysis — Structural damage inspection: every deformation pattern is evidence.

AT A GLANCE

Engineering degree	Hertfordshire 2006
Crash research	Cranfield, EPSRC
Inspection practice	Current, daily
Reports	CPR Part 35 format
Coverage	UK-wide · international
Professional indemnity	£2m insured
APIL directory	Expert Witness listed
UK Register	Vetted expert
Data protection	ICO registered (ZC197605)

Free 10-Minute Case Call

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Collision damage analysis · vehicle assessment · expert reports

Is the damage consistent with the accident?

Vehicle engineering analysis