Articles
Wind turbine blades, explained by the engineers who investigate them
How blades fail, how they are made, what damage costs, and how it is found. Written for insurers, owners, lenders and engineers, by Apex Wind.
Mohammed Fajar · 10 min read
Wind turbine blade inspection checklist: what to check, how, and what each finding means
A working blade inspection checklist for external, internal, root and post-event inspections, with the method for each item and what the finding means for the repair decision.
Read the articleMohammed Fajar · 9 min read
When does blade damage require repair? Damage categories and the decision behind them
How blade damage categories work, when damage is cosmetic, when it is structural, and how owners and insurers decide between repair now, repair at the next campaign and monitor.
Read the articleMohammed Fajar · 9 min read
Erosion, lightning or a bond line crack? How to distinguish blade damage types
How to tell blade damage types apart from an inspection image: erosion against coating failure, lightning against impact, bond line cracks against laminate cracks, and defect against repair.
Read the articleMohammed Fajar · 9 min read
Trailing edge cracks: what causes them, how they are diagnosed, and when they are structural
Trailing edge cracks are the most common structural finding on wind turbine blades. What causes them, how to diagnose one from an inspection, and when the crack stops being a repair item.
Read the articleMohammed Fajar · 9 min read
Lightning damage to wind turbine blades: diagnosis, receptor testing and what IEC 61400-24 requires
How lightning damages a wind turbine blade, how a strike is diagnosed after the event, how the protection system is tested, and what IEC 61400-24 requires of it.
Read the articleMohammed Fajar · 9 min read
IEC 61400-5 explained: what the blade standard requires, and what it does not
IEC 61400-5 is the first international standard dedicated to wind turbine blades. What it covers, how it relates to blade testing and certification, and what an owner or insurer can ask for under it.
Read the articleMohammed Fajar · 9 min read
Measuring blade aerodynamic flow state: what attached and detached flow cost in power
How a blade aerodynamic flow state sensor on two V27 turbines split the power curve: attached flow +15%, detached flow -30%, and a per-blade pitch trim method.
Read the articleMohammed Fajar · 9 min read
Wind turbine blade monitoring compared: drones, sensors, SCADA and satellites
Wind turbine blade monitoring compared: drones, robots, blade sensors, SCADA anomaly detection and Sentinel satellites. What each detects, misses and costs.
Read the articleMohammed Fajar · 9 min read
Wind turbine blade icing: production losses, loads and what owners can do
How wind turbine blade icing forms, what it costs in production and loads, how ice is detected and mitigated, and how icing damage is told from other causes.
Read the articleMohammed Fajar · 9 min read
Leading edge erosion: how much energy it costs, and when it turns structural
How leading edge erosion starts and progresses, what studies say it costs in energy and revenue, and when it becomes a structural and insurance question.
Read the articleMohammed Fajar · 10 min read
The wind turbine blade manufacturing process, and where defects enter
How the wind turbine blade manufacturing process works, the defect each stage can introduce, from wrinkles to kissing bonds, and what a factory audit looks for.
Read the articleMohammed Fajar · 9 min read
Laminate wrinkle wind turbine blade: how one defect becomes a serial defect
How a laminate wrinkle wind turbine blade defect forms in the spar cap, why it cuts compressive strength, how it is found, and when it becomes a serial defect.
Read the articleMohammed Fajar · 10 min read
Blade root insert failure: why root connections fail and how to catch it early
How blade root insert failure develops in bonded inserts and T-bolt roots, what inspection can find before blade detachment, and how the cause is established.
Read the articleMohammed Fajar · 9 min read
The cable-stayed rotor: what the Vestas patents cover and why it matters for large blades
How the cable-stayed rotor works, what the Vestas patents co-invented by Mohammed Fajar cover, what is publicly known, and what it means for large blades.
Read the articleMohammed Fajar · 9 min read
Wind turbine blade failure: causes, warning signs and how it is investigated
What causes wind turbine blade failure, the warning signs before it, and how an independent investigation separates an isolated event from a serial defect.
Read the articleMohammed Fajar · 9 min read
The technology qualification wind turbine blades over 100 m will need: an FMECA-based plan
What technology qualification wind turbine blades over 100 m need: a full FMECA mapped to DNV-RP-A203 evidence, from a 2026 paper Mohammed Fajar co-authored.
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