The original flat wing pattern was developed by the late Bill Peabody a well known fly tyer and fisherman from Rhode Island in the US. The original pattern was developed for stripped bass but was also found to be just as successful on many other salt water species. Recently a number of flat wing patterns have been developed for salt water sea trout and sea bass fishing in Northern Europe and have proved to be extremely effective.
One of the great things about tying these modern flat wing patterns is that the design lends itself extremely well to individual interpretation in size, colour and material use. But remember that the key word for tying flat wings is sparse, if you over dress these flies you defeat the whole point with them. Try and use materials that are light but create volume, but always consider the movement of the material in the water when fished and don´t forget its reflective and flash qualities. Some fly tiers also make use of a tandem hook on larger patterns, attached by mean´s of a wire or mono extension with the tail hook, up side down. But I find that this in most cases completely changes the action of the fly.
Sea trout Flat wing streamer recipe
Hook Mustad S71SNP-ZS # 8-2
Tying thread Dyneema
Tail Two flat wing saddle hackles and Flashabou
Body Mother of pearl Body Braid coated with Bug Bond
Under wing White buck tail and five strands of Crystal flash
Over wing Yellow Olive and blue buck tail mixed
Topping Five strands of fine peacock herl
Throat White buck tail
Cheeks Jungle cock