The fluorescence lifetimes of 115 vibrational levels of the (A) over tilde (1)Pi(u) state of C-3 have been measured under supersonic molecular beam conditions. Of these, ninety-one are Pi(u), vibronic levels, for which the lifetimes lie in the range 190-700 ns. The lifetimes of those flu levels where only the bending vibration is excited lie in the range 190-235 ns. There is very little variation with bending quantum number, and the lifetimes of the two orbital components of the (1)Pi(u) state are essentially the same. When v(1) and v(3) are excited, the lifetimes become longer and/or reach a maximum for levels with v(1) + v(3) similar to 4. Excitation of the bending vibration in addition to the stretching vibrations shortens the lifetime slightly. Several of the levels show double-exponential decays. Another 23 levels, of Sigma(+)(u): vibronic symmetry, mostly have lifetimes that are longer than 300 ns. Interaction with nearby "dark" electronic states, such as (B) over tilde (1)Sigma(-)(u), (B) over tilde '1 Delta(u,) (C) over tilde (1)Pi(g), and (b) over tilde (-3)Pi(g), is proposed to account for the observed lifetime lengthening. A particularly clear instance of such an interaction is the long lifetime (914 ns) of a perturbing Sigma(+)(u) level at 30 181 cm(-1), which is confirmed as belonging to the perturbing (B) over tilde'(1)Delta(u) (1)Delta(u) state. A single level of Delta(u) symmetry at 29 170 cm(-1), which perturbs one of the levels, is shown to belong to the A state.