Line Profiles

On the package of every fly line is a code. The first element is a description of the profile. A line profile is a description of the profile or side view of the line that gives the angler an indication of how the weight is distributed along the lines length and how it is tapered. Below is a description and discussion of each of the major types of line profiles.

 

Double Taper:

Below is an illustration of what is called a Double Taper (DT) line. It is tapered evenly at both ends unlike the weight forward line below it. Double tapered lines are the heavier along their entire length than a weight forward line but will still fall within the AFTMA specifications for the first 30 feet of the line. Notice that this line has no proper "front" to it as do the other two tapered lines so it doesn't matter which end is attached to the backing. Double tapered lines used to be recommended as a beginner's first line, but most people are sold a weight forward these days.

  

Pros: Double Tapered lines are better for making on the water mends than a weight forward line. They can be turned around on the reel if needed for added life, though few people do so. They allow the angler to roll cast farther than with a standard weight forward line.

Cons: They take up more space on the reel cutting down on the backing capacity. The angler will not be able to shoot as much line due to the extra weight over the weight forward line.

 

Weight Forward:

The next line is a Weight Forward (WF) line. This is the most popular of all the tapers. It is the line profile most manufacturers use when designing regular and specialty lines.

  

Pros: When shooting line, this will cast farther than the double taper because it does not have to pull as much weight behind it due to the thin running line. This same feature also allows the reel to store more backing than the double taper.

Cons: It will not roll cast as far as a double taper.

 

Single Taper:

This next line illustration shows a Single Taper (ST) also called a Shooting Head (SH). The level line directly behind it in the illustration below indicates an attached running line. The running line is of a small diameter increaseing the shooting distance of the line due to that thin diameter. These single taper lines are usually only about 30 feet in length with up to 100 feet of running line while the other tapers above range from 80 to 105 feet in length.

  

Pros: Longer casts can be made while making fewer false casts to get that distance. The "heads" can be easily changed on the stream without need of carrying extra reels or spools. The heads come in differing sink rates: Floating, Intermediate (slow) sink, and increasingly faster sink rates (Type 1 through Type 8).

Cons: These lines are somewhat difficult to cast compared to the other profiles. Running line management can be challenging. Mending is almost nonexistent. The sinking heads must be roll cast to the surface prior to picking the line from the water.

 

Level:

The level (L) line is a line without a taper (see below). These are seldom seen used except when attached as running line behind a shooting head. It will not work well for delivering a fly. Due to poor dissipation of energy the line will "kick" as it turns over and will dump the line instead of allowing the leader and fly to turn over. Kicking can occur with any fly line if the line is not terminated properly with a good leader.

  

A dumped line does not turn over; instead the force of the end of the fly line is directed down and will pull the leader with it, 3 to 5 feet short of its full length. Taking into account the length of the leader this could easily leave the fly 10 to 15 feet short of its target. This affect is also found in sinking lines with little or no front taper. This is discussed further in the salt water tackle sections.