Over-under split shot of Soufrière Bay, Dominica — lush coastline above, clear blue water below

AIDA Master Instructor · Soufrière Bay, Dominica

Calm is taught,
not forced.

From a first held breath to competition depth — courses, depth coaching and camps built on relaxation, efficient technique and a calm nervous system. Not pushing.

Photograph · Allie Reilly
Master
AIDA Instructor rating
250+
Students taught
5
Countries coached in
Allyr
Year-round in Dominica
I · The approach

Teach the nervous system,
not just the dive.

As an AIDA Master Instructor, Harry has certified over 100 students — from first breath-holds to competition depth. The method is the same calm that defines his own diving: relaxation first, efficient technique second, depth as the result — never the goal.

  • Relaxation and breath-up — where every dive is actually won
  • Equalisation that scales with depth — Frenzel, then mouthfill
  • Streamlined technique and efficient finning — or none at all
  • Safety, rescue and the mental side of going deep, calmly
Harry McCahill floating on his back at the surface, breathing up before a dive The breath-up — where every dive is won Allie Reilly
II · What you can train

The AIDA ladder —
beginner → instructor.

Full AIDA certification pathway, taught year-round in Dominica. Start with your first breath-hold or arrive with depth already and refine it — every course is run in small numbers, at your pace.

AIDA 1Discover
A one-day introduction — breathing, relaxation and your first breath-hold dives in shallow, confined water. No experience needed.
to ~10m
AIDA 2Foundation
The complete foundation — relaxation, equalisation, finning technique, buddy safety and rescue. The real start of depth freediving.
to ~20m
AIDA 3Advanced
Free immersion, the first mouthfill, refined technique and longer dives — building the toolkit to keep descending comfortably.
to ~30m
AIDA 4Master
Advanced equalisation, packing, and the calm of real depth — for divers committing to the deep end of the sport.
to ~40m
InstructorTeach
For divers ready to teach — instructor development and crossover, mentored by a Master Instructor. By application.
Pro
III · 1:1 Coaching

Coaching built
around you.

Beyond the set courses, Harry takes on a small number of divers for ongoing one-to-one coaching — your technique, your goals, your timeline. It starts with a discovery call to understand where you are and where you want to get to.

  • A plan shaped around your current depth and goals
  • Video review, dive analysis and personal feedback
  • Dryland support and breath-work between sessions
  • Competition prep and dive planning when you're ready
Book a call
Two freedivers on the surface beside the line in Soufrière Bay, Dominica One-to-one, by the line Allie Reilly
IV · Depth camps
Three freedivers descending the line into deep blue water, Soufrière Bay, Dominica Coached line sessions · Soufrière Bay Daan Verhoeven

Regular depth camps
in Dominica.

Several times a year, Harry runs small-group depth camps in Soufrière Bay — one of the world's premier depth-training locations. No waves, no current, no boat ride — just deep, warm, sheltered water a few fin-kicks from shore.

  • WhereSoufrière Bay, Dominica — sheltered, volcanic, deep right off the shore
  • WhoAIDA 3+ divers and competitors working on depth, in small groups
  • WaterWarm and still year-round · over 100 m within swimming distance
  • CoachingDaily coached line sessions, video review, dive planning and safety
Enquire about a camp
V · Dates & calendar

When we dive.

Private courses and coaching run year-round in Dominica — booked around your travel. Group depth camps are scheduled several times a year and released seasonally.

Request upcoming dates
VI · Around the world

One bay at home,
many waters abroad.

Dominica is home — but the work has taken Harry to freediving's great depth destinations, coaching and diving across four more countries.

Home base
Dominica
Soufrière Bay — year-round courses, coaching and depth camps.
Caribbean
Mexico
Baja California
The Sea of Cortez — deep, blue and warm on the Pacific side.
Mexico
Cenotes of the Yucatán
Still, glassy freshwater caverns — silent depth in the jungle.
Indian Ocean
Maldives
Atoll water — clear, warm and endless blue below.
Europe
France
Coaching and diving in the Mediterranean and beyond.
Europe
Greece
Calm Aegean depth — a heartland of the sport.
VII · Who I coach

From first breath
to competition depth.

Over 250 divers have trained with Harry — and the same calm method scales from someone who has never held their breath underwater to athletes chasing national records.

First breath
Complete beginners
Never dived on a single breath before? Start here — calm, unhurried and safe.
Recreational
Club & ocean divers
Build confidence, depth and technique for the diving you already love.
Performance
Competitive athletes
Depth coaching, dive planning and competition prep — to national level and beyond.
Comp prep
Pro
Instructor candidates
Mentoring for divers ready to teach, toward AIDA instructor ratings.
VIII · In their words

What it feels
like to train.

A few words from divers who have trained with Harry — from a first held breath to competition depth.

I went from nervous on the surface to calm at thirty metres in four days. Harry never once pushed — he just made the depth feel like the safest place to be.
Sarah · AIDA 2 · United Kingdom
The calmest, most patient coaching I have had. Every session ended with me wanting to go slower, not deeper — and the depth came anyway.
Marco · Club diver · Italy
Harry rebuilt my dive from the breath-up down. Two national-record attempts later, the difference is all in the relaxation he taught me.
Elise · Competitor · France
My first time holding my breath underwater, and I never felt rushed or unsafe. I left the course wanting to make this a part of my life.
Tom · First course · Australia

Start your training

Learn to let go.

Take your first course, deepen an existing one, or join a depth camp in Dominica. Tell me where you are and where you want to get to.

Get in touch See the records