Study material
FFI fly casting definitions
How the definitions are organised, the core loop vocabulary, and why the exam expects you to know them.
Fly casting instruction depends on a shared vocabulary, and the CI exam expects candidates to know FFI’s. These definitions “help instructors and others with a serious interest in Fly Casting communicate more clearly with each other” — they are reference terms, not necessarily teaching terms.
The full, current document lives on FFI’s site — updated 1 August 2025, with new or changed items marked: FFI Fly Casting Definitions.
On this site: the complete definitions are also published as FFI Fly Casting Definitions (2025 Edition) — the same reference kept locally so you can link to it while studying.
How the document is organised
| Section | What it covers |
|---|---|
| Fly Casting | The definition of the activity itself |
| Loops | Loop, fly leg, rod leg, loop nose |
| Fly Leg Shapes | Straight, convex, concave, trailing, tailing |
| Fly Casting Movements | The movements that make up a cast |
| Rod Movements During the Pause | What the rod does between strokes — drift, creep |
| Casting Terms | The working vocabulary: mend, reach mend, D-loop, anchor, 180-degree principle, pause, stroke, RSP1, tracking, plane |
| Casts and Techniques | The named casts the exam uses |
| Physics Terms for Fly Casting | The physics vocabulary added in 2025 |
The core loop vocabulary
- Fly Cast — using a flexible lever to move and unroll a weighted line to propel an artificial lure.
- Loop — the shape a fly line assumes as it overtakes the rod tip during a fly cast.
- Fly Leg — the moving section of line in a loop, from the fly to the start of the loop nose.
- Rod Leg — the moving or stationary section of line in a loop, from the rod tip to the end of the loop nose.
- Loop Nose — the curved section at the front of the loop, between fly leg and rod leg.
- Straight Fly Leg — fly line and leader relatively free from curvature from the loop nose to the fly.
- Convex Fly Leg — a fly leg domed away from the rod leg.
- Concave Fly Leg — a fly leg that is not straight and dips toward the rod leg.
Those fly-leg shapes are exactly what the performance exam asks you to produce on demand in Task 1, Task 2 and Task 3, and they are the first review questions on the paper exam.
Why candidates should read it twice
- The exam states that candidates are expected to be familiar with the terms and their definitions.
- Several definitions changed in the 2023–2025 revisions (the document marks them), so older articles and books may use terms differently — the teaching manuscripts warn about this explicitly.
- Explaining a cast to a student is easier when your own vocabulary is precise: the CI is an instructor certification, and Part Two is assessed on clarity.
Compiled for personal study from FFI's public material; FFI's original documents remain the authority and are linked from this page.