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The cyanovinyl radical has been proposed to play important roles in the interstellar chemistry of neutral-neutral reactions and the combustion chemistry of heavy fuels. However, no spectroscopic study was available before. We have observed two isomers of this carbon chain from: $H2CCCN$ and CHCHCN in their $X2A\prime$ states with a Fourier transform microwave spectrometer, generating them in a pulsed-discharge nozzle with the $CH3CN/Ar$ or $CH2CHCN/Ar$ gas mixtures. The rotational constants from the observation are in good agreement with the values from ab initio calculations (RCCSD(T)/cc-PVTZ) by one percent. The observed spectra of both isomers showed very complicated patterns due to the comparable order of magnitude for the spin-rotation interaction and the nuclear hyperfine interactions from the three nuclei H and N, which made the traditional way of assignment incapable. An approach of maximizing a cross-correlation between experimental and simulated spectra has been applied to the assignment of the massing spectra. Result and progress will be presented.