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An infrared absorption spectrum of $C2H5$ has been observed by diode laser spectroscopy in the region $520-550cm-1$. The radical was formed by excimer laser photolysis of $C2H5I$ at 248 nm or $(C2H5)2CO$ at 193 nm. Both precursors showed the same transient absorption spectrum and the spectrum is close to the position of the strongest infrared absorption band assigned $C2H5$ in low temperature matrix $spectra1$. The gas phase spectrum is very complicated, however 5-6 rotational progressions can be identified. The complexity of the spectrum seems most likely due to strong interaction between the $\nu 9$ (pyramidal distortion) vibration and the low frequency torsional (internal rotation) mode. Another possibility is that the radical center is non-planar and the spectral complexity is due to inversion doubling, however this seems a less likely explanation at present. Progress on the analysis of the spectrum will be reported at the meeting. This research was carried out at Brookhaven National Laboratory under Contract No. DE-ACO2-76CH00016 with the U. S. Department of Energy and supported by its Division of Chemical Sciences, Office of Basic Energy Sciences.