Flight feather
Videos
Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges, singular remex, while th
Red kite (Milvus milvus) in flight, showing remiges and rectrices
Bald eagle (Haliaeetus leucocephalus) in flight with primaries spread to decrease drag and improve lift
Primary (left) and secondary (right) feathers of the common buzzard (Buteo buteo); note the asymmetrical orientation of the shafts
Secondaries of a pheasant showing eutaxis (above) and an eagle showing diastataxis (below)
Covert feather
Videos
A covert feather or tectrix on a bird is one of a set of feathers, called coverts, which cover other feathers. The coverts help to smooth airflow over the wings and tail.
Flight feather
…on each wing, a state known as diastataxis (those that do have the fifth secondary are said to be eutaxic). In these birds, the fifth set of secondary covert feathers does not cover any remiges, possibly due to a twisting of the feather papillae during embryonic development. Loons, grebes, pelicans, hawks and eagles…
A rear view of an Indian peacock's true tail and elongated uppertail covert feathers