The Fly Bench LogoThe Fly Bench Logo

You Might Also Like

Bird's Nest
Bird's Nest
Parachute Floating Nymph
Parachute Floating Nymph
The Crack-Back Aero PMD
The Crack-Back Aero PMD
Foam Wing RS2
Foam Wing RS2
Sparkle Wing RS2
Sparkle Wing RS2
Big Bear Emerger
Big Bear Emerger
Mercury RS2
Mercury RS2
Barr's Vis-A-Dun
Barr's Vis-A-Dun
Possie Bugger
Possie Bugger
The Fly Bench LogoThe Fly Bench Logo

TheFlyBench

  • About The Fly Bench
  • Privacy Policy
  • Browse All Patterns

Pattern Categories

  • Dry Flies
  • Nymphs
  • Streamers
  • Scuds & Shrimps
  • Midges & Emergers
  • Euro Nymphs
  • Saltwater
  • Leeches

© 2026 The Fly Bench. All rights reserved.

Midge / EmergersRS2

Versatile and effective fly imitates a range of small aquatic insects. The slim body and CDC wing make it an excellent imitation of a hatching midge or mayfly. Simple design is key to its success, particularly in pressured waters where fish see many patterns.

Season
Spring, Summer, Fall
Difficulty
Intermediate
Target Species
Trout
Updated
Apr 2025
RS2 fly pattern - imitates Midges, Mayflies tied for Trout

Overview

Slim emerger pattern developed by Rim Chung in the late 1970s, typically tied with a gray or olive thread/dubbed body, sparse microfibbet tail, and a small CDC or Antron wing. Its simplicity is key to its success in fooling selective trout. Often used in smaller sizes (#18-24) during BWO or midge hatches on tailwaters and spring creeks. The minimal materials create a delicate profile that sits naturally in the surface film.

Materials

Hook: Tiemco 101, sizes #16–#22
Thread: Olive Brown UTC 70 Denier
Tail: Brown saddle hackle or elk hair
Abdomen: Olive Brown Superfine
Wing: CDC oiler puff
Thorax: Olive Brown Superfine

Behavior & Presentation

Natural Behavior: During emergence transitions, small mayflies and midges hang suspended just beneath the surface film as their bodies transform, wings partially unfolded and vulnerable. This transitional zone creates easy feeding opportunities for selective trout.

Where Trout Eat It: Fish suspend just below the film in smooth water, slicks, and tail-outs at depths of 6-18 inches during hatch activity.

How to Fish It: Dead drift in or just below the film, maintaining natural speed without drag or unnatural movement.

Best Water: Target slicks, tail-outs, back eddies, and seams at spring creek margins and tailwater runs where emergers concentrate.

Strike Type: Watch for subtle sips, indicator hesitations, or barely perceptible film movements as fish take gently.

Fishing Strategy

Rigging Suggestions: Try it as the top fly in a tandem nymph rig or on a dropper 18-24 inches off a dry fly. Use 5X-6X fluorocarbon tippet for delicate presentation.

Seasonal Timing: Most productive March-May and September-November during periods when midges and small mayflies are hatching. Water temperatures between 45-65°F are ideal.

Pro Tips: This fly is designed to sink to imitate an emerging insect. The CDC wing adds some movement and visibility, but it is a subtle pattern designed to fool wary fish in clear water.

Entomology

Small mayflies and midges drift in the transitional zone just below the water's surface as they prepare for emergence, their wing cases darkening and bodies beginning to shed their nymphal shucks. Fish position themselves in feeding lanes to intercept these ascending insects, which represent an easy target during the vulnerable transformation from aquatic to terrestrial life stage.

Order
Ephemeroptera
Common Name
Mayfly
Organism Type
insect
Life Stage
general

Pattern Characteristics

Intermediate Difficulty
Trout
Stillwater
Moving Water
Spring
Summer
Fall
Imitates: Midges, Mayflies
Essential Pattern
Rocky Mountain
Worldwide
South Platte River
Fryingpan River
Taylor River
Bighorn River
Provo River
classic
guide-fly
dead-drift
dry-dropper
beginner-friendly
baetis-hatch
midge-hatch
tailwater
spring-creek
low-clear-water

Additional Videos