Ed Jaworowski's Functional Fly Casting, Video 3: Critical Angle

The angle between your fly rod and fly line determines the amount of energy you can put into a cast.

April 22, 2025 By Ed Jaworowski; Filming by Ben Annibali

EDITOR'S NOTE: Casting master Ed Jaworowski takes a deep dive into the fundamentals of fly casting in his five-part series “Functional Fly Casting,” which ran in each issue of Fly Fisherman in 2025. This is the third in a series of five videos examining the physics and mechanics that determine the outcomes of all casts, based on Ed Jaworowski’s nearly 70 years of casting, testing, experimentation, teaching, and consulting with physicists, kinesiologists, and engineers.

During a conversation with a physicist 30 years ago, it became clear to me that the angle between the rod and the line coming from the rod tip, at the moment you start to load the rod, is of great importance. It may and should vary, depending on the amount of bend or load you require for each cast. This assumes, of course, that there is no slack in the line, and it applies to both the back and forward casts. At that time, I had not seen any discussion of this in previous angling literature, so I named it “the critical angle” to draw attention to its importance.

A critical angle of 90 degrees—meaning the line is at a right angle to the tip—is the least efficient, mechanically speaking, but may be adequate if you don’t require a deep rod load and are making short casts. The load or bend will be near the tip. On the other hand, a critical angle of 180 degrees—meaning the line comes from the tip in a straight line—assures the greatest mechanical efficiency, because as soon as your hand starts to move and rotate, the load will develop well down into the rod butt, storing more energy.

There can be no fixed or predetermined positions or “times” such as 10 o’clock or 2 o’clock for starting and stopping the rod. By combining a wide critical angle with a smooth, efficient acceleration and stop, you can make 70- and 80-foot casts with no more effort than you use to cast 30 feet.

In addition to the distance you want to cast, take into account other factors, such as resistance from the fly and the wind. To cast a heavy fly under adverse conditions you would need more load than to cast a light fly under ideal conditions, even though the distance is the same for both casts. However, the starting critical angles would be different for each. Question any instruction that categorically advises starting with the rod at some point corresponding to a certain time on a clock without defining the needs of the cast. As I suggested in the previous article in this series: Cast smarter, not harder.

A fly angler wading shin-deep demonstrating a fly-casting technique. — (Ben Annibali photo)

When you look at casting photos or videos depicting back or forward casts, take note of the critical angle at the start of any cast and observe the load that develops by the time the hand stops applying its force on the grip. What still photographs can’t convey is the speed of the move and the remarkable lack of effort required to achieve a deep bend when using a wider critical angle. However, sequence photos and videos clearly reveal that when starting with the rod and fly line at a very wide critical angle, coupled with a smooth acceleration, the rod loads effortlessly into the lowest part of the blank, storing much more energy. This is generally easier to accomplish if the cast is made with the rod tilted off to the side, not in a vertical or straight overhead path, and employs more body leverage, as discussed in my previous article.

Scale Tests

Years ago, when Lefty Kreh and I were working on an instructional DVD, we filmed tests to demonstrate the advantage of a wider critical angle. We tied the line to a scale and used cameras placed to the side and overhead. We found that by starting with the rod and line at a 90-degree angle and moving the casting hand forward as in making a cast, it was impossible to get much bend into the rod. The scale showed a pull of less than a pound, even though my hand and arm were straining against the grip. When we performed the same test with the rod and line beginning at 180 degrees, it was easy to generate more than 7 pounds of load in the rod.

Here’s a simple test you can perform. Hold the rod pointing off to the side, as if making a sidearm cast. Extend a few feet of line from the tip and have someone pinch the end of the fly line between a thumb and index finger and hold it at 90 degrees to the rod tip. Let the caster try to load the rod by slowly moving the grip forward. Even though the caster’s hand exerts great force, the line holder will feel very little pull because the rod has only a slight load.

Now, while exerting steady pressure on the line, have the caster walk slowly forward, ever widening the critical angle toward 180 degrees, until the rod is pointing almost straight toward the line holder. Observe how the curve of the rod progressively moves down into the butt, and that the person holding the line in his fingers feels greatly increasing pull and may not even be able to hold onto the line. Now, have the rod holder steadily back up, again moving the critical angle toward 90 degrees. The line holder will immediately feel the pressure lessen as the bend in the rod moves back up into the tip. Casting is a matter of angles and levers.

Capt. Jake Jordan of North Carolina has taught countless anglers who pursue strong oceanic gamefish to employ the same concept of a very wide rod-to-line angle, and in the process revolutionized big-game fly fishing, even enabling anglers to catch blue marlin of several hundred pounds using 20-pound-test tippet.

Years ago, I competed in surf-casting distance competitions and came to understand that the principle of critical angles also pertained to spinning and conventional casting tackle. This produced deeper loads in the rod more easily.

Most spin fishers take their rod back to the rear, over the shoulder, and begin the cast while the lure or sinker is hanging down from the rod tip. That represents a small critical angle. However, competitors in our tournaments achieved the best loads and longest casts by taking the rod well to the rear, swinging the weight back and straight out from the tip to 180 degrees, and starting the forward cast before the weight could fall back. Casts in the vicinity of 500 feet were common, with a 10½-foot conventional surf rod and a 4-ounce sinker.

Another advantage of widening the critical angle is limiting, or even eliminating, false casts in many cases. False casts are clearly necessary at times, but too often they are used to compensate for poor casting technique. That’s why I encourage anglers to understand the mechanics of the cast and commit to practice, which is the price of skill. Focus on acceleration, rotation, leverage, and the critical angle. These are the keys to becoming a truly proficient caster.

In the next video, I’ll be discussing the backcast.

Ed Jaworowski is the author of Perfecting the Cast: Adapting Casting Principles for Any Fly-Fishing Situation (Stackpole Books, 2021) and coauthor of Pop Fleyes: Bob Popovics’s Approach to Saltwater Fly Design (Stackpole Books, 2014).