AM Thruster Fins: Why This Template Changed Performance Surfing

Written By Graeme Gillmer

AM thruster fins are one of the most popular surfboard fins setups ever designed—built for speed, drive, and clean release in modern thruster fins configurations.

What Are AM Thruster Fins?

AM thruster fins refer to the high-performance fin template made famous by Al Merrick of Channel Islands Surfboards.

They are designed for performance shortboards, delivering a balance of:

  • Speed down the line

  • Drive through turns

  • Controlled release off the top

This template has become a benchmark in surfboard fins design, especially for surfers pushing progression in everyday to powerful conditions.

The Core Design Explained

Here’s what actually makes AM thruster fins different:

1. Raked Template (More Sweep)

  • The fins lean back more than upright templates

  • Creates longer turning arcs

  • Generates more drive and speed

👉 Think: drawn-out, powerful turns rather than tight pivots

2. Asymmetrical Thruster Setup (Key Feature)

Unlike many standard thrusters, AM-style setups often use:

  • Larger side fins

  • Slightly smaller centre fin

Typical proportions:

  • Side fins: ~4.7"–4.75"

  • Centre fin: ~4.5"

What this does:

  • Side fins = generate drive and hold

  • Smaller centre = reduces drag

  • Result = faster release and less “tracky” feel

👉 This is one of the biggest reasons surfers instantly feel the difference.

3. Foil Configuration

  • Side fins: Flat inside foil → maximises drive and speed

  • Centre fin: 50/50 foil → adds control and smooth transitions

👉 Translation: You get speed from the sides + stability from the centre

How AM Thruster Fins Feel in the Water

Performance AreaFeelSpeedFast, especially down the lineDriveStrong projection out of turnsTurningSmooth, drawn-out arcsReleaseClean and predictableControlStable but not stiff

👉 If your current setup feels slow or sticky, this template usually fixes it.

AM Thruster Fins vs Other Templates

AM vs Upright (Pivot) Thruster Fins

FeatureAM TemplateUpright / PivotTurning StyleLong, carving arcsTight, quick turnsSpeedHighModerateReleaseSmoothSnappyBest ForOpen faces, power surfingSmall waves, quick direction changes

AM vs Neutral Template

  • Neutral fins = balanced, “do everything OK”

  • AM fins = performance-biased (speed + drive)

👉 If you want progression, AM wins.

When Should You Use AM Thruster Fins?

Best Conditions:

  • Waist-high to overhead surf

  • Clean faces

  • Point breaks and open beach breaks

Best Boards:

  • Performance shortboards

  • Hybrids with rocker

  • Step-ups

Best Surfers:

  • Intermediate to advanced

  • Anyone looking for more speed and projection

When NOT to Use AM Thruster Fins

They’re not ideal when:

  • Waves are weak and slow → can feel “too drawn out”

  • You want ultra-tight turns → pivot fins are better

  • You’re riding grovellers → consider smaller or more upright templates

👉 Discover the best fins for small waves.

Why This Template Became the Industry Standard

The AM template is widely used because it solves a core surfing problem:

👉 How do you get speed AND control without feeling stiff?

It achieves this by:

  • Generating drive from the side fins

  • Reducing drag via the centre fin

  • Maintaining control through foil balance

That combination is why this design is still one of the most copied templates across surfboard fins globally.

Eveley Performance

If you're looking to replicate this performance profile using Eveley fins, focus on:

Recommended Setup:

  • Raked side fins (Pro Glass construction)

  • Slightly smaller centre fin

  • Medium flex profile

👉 4.75" AM2 Thruster Fins – Black Pro Glass, FCSII Compatible

👉 4.75" AM2 Thruster Fins – Black Pro Glass, FCS Compatible

👉 Why Eveley Pro Glass works:

  • Solid fibreglass = consistent flex

  • Better hold at speed

  • More predictable release than lighter constructions

AM Thruster Fins Setup Tips (Immediate Gains)

1. Move Your Centre Fin Slightly Forward

  • Loosens the board

  • Increases responsiveness

2. Don’t Oversize the Centre Fin

  • Too big = kills the AM advantage

  • Stick to slightly smaller than sides

3. Match to Your Weight

Surfer Weight Suggested Size < 70kg Small 70–85kg Medium 85kg+ Large

Common Mistakes

  • Running equal-sized thruster fins → removes release benefit

  • Using AM template in weak waves → feels slow

  • Mixing incompatible flex patterns → inconsistent feel

Surfboard Fins Knowledge Hub

Build your full understanding here:

FAQs

What does “AM” mean in surfboard fins?

It refers to the performance template popularised by Al Merrick, designed for speed, drive, and clean release.

Are AM thruster fins good for beginners?

They can work, but beginners may prefer neutral templates first. AM fins are best once you’re generating speed and turning properly.

Why is the centre fin smaller in AM setups?

To reduce drag and allow faster release while maintaining control from the side fins.

Are AM thruster fins good in small waves?

Not ideal. They perform best when there’s enough wave energy to engage the raked template.

Final Takeaway

If you want your board to feel:

  • Faster

  • More powerful

  • Less “stuck” in turns

👉 AM-style thruster fins are one of the most proven upgrades in surfboard fins design.

They’re not hype—they’re a performance blueprint that still works today.

Futures™ is a registered trademark of Futures Fins. Eveley Surf is not affiliated with or endorsed by Futures Fins. All compatibility references to Futures Fins are for descriptive purposes only.

FCS™ and FCSII™ are registered trademarks of Surf Hardware International Pty Ltd. Eveley Surf is not affiliated with or endorsed by Surf Hardware International Pty Ltd. All compatibility references to FCS and FCSII are for descriptive purposes only.

Graeme Gillmer
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