Fly Casting - Tailing Loops
There's been a lot said about tailing loops in the past (and more to come I'm sure) Much of it is just wrong and postulated by casters that simply don’t know any better. The topic can be an incredibly complex one.
Having seen a few tails and created more than my fair share - most entirely involuntarily - I think it best to keep things simple. After-all, we're all about fly fishing rather than any in-depth analysis of casting physics.
Fly fishing and fly casting are most certainly the sport of exceptions and in order to attempt to explain anything in fly casting you tend to have to generalise - and that’s what i’m about to do.
There are all sorts of potential, “Yeah but’s" - “What about when’s” and “sometimes” that can be thrown into the mix - but most often, and for most of us fly anglers this is the go….

What is a tailing Loop?
The FFI definition of a tailing loop and that which seems to be agreed upon by most qualified fly casting instructors is that a tailing loop sees the line crossing over itself AND back again. i.e twice.
A crossed line is not a tailing loop by definition. It's all sorts of other things. An under slung loop, a tight loop cast out of plane, a loop commonly seen on spey casters - all sorts - but it's not a tailing loop. See below. THIS IS NOT A TAILING LOOP

What makes tailing loops.
Simple - it's always the path the rod tip makes. It can't be anything else. And if you doubt that think about the point of control between the fly line, rod and caster - it's the tip of the rod. End of story.
Most diagrams you’ll see of tip paths depicting the cause of tails are very much exaggerated - including mine here. The effect is subtle, while you’ll certainly see the resultant tail, you'll most likely not actually see the cause in the tip path.
What does the rod tip do to cause a tailing loop?
Simply, the rod tip dips down and then rises back up again. And it needs to do both those things during the casting stroke. Dipping down isn’t the issue, the dip then rise is what does the damage. Most often this variance can be extremely subtle and almost impossible to see and can be most anywhere in the casting stoke. In my experience most often either very early - or very late in the stroke.
What causes the rod tip to drop and rise up again?
Potentially many many things, common teaching dogma cites the following as the most common causes:
- Poor power application / abrupt power - shocking the rod at the start of the stroke. Or horsing the rod at the very end (throwing)
- Too narrow a casting arc for the amount of line past rod tip
- Breaking the 180 degree rule (high back cast + high forward cast)
- Creep (too narrow a casting arc and often abrupt power application)
- Finishing the haul too soon
... and just about anything else you can come up with.
In short, most tailing loops are caused by problems with power application. e.g, too narrow a casting arc simply means you need to pack all the power and acceleration required to keep the line aerialized into a very short stroke, which would usually result in a tail. Apply the same power over a longer stroke and your tail will disappear.
The Fix?
Be smooth. If you see tails, smooth out how you apply power. Often, simply buttoning off the power will effect a fix. And / or make a longer stoke.
Much if this stuff is explained in our fly casing video 'Casts that Catch Fish' - although if I did it again i'd probably explain things a little differently ;-)