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In all previous experimental studies of the thermal decomposition of acetaldehyde (CH$3$CHO), the products were presumed to be CH$3$ + CHO. These species result from cracking of the weakest bond. Other routes are possible: (DH$\mathrm{<mrow\; data-mjx-texclass="ORD">298</mrow>}$(CH$3-$CHO) = 84.8 $\pm$ 0.2 kcal mol$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$; DH$\mathrm{<mrow\; data-mjx-texclass="ORD">298</mrow>}$(CH$3$CO-H) = 89.4 $\pm$ 0.3 kcal mol$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$; DH$\mathrm{<mrow\; data-mjx-texclass="ORD">298</mrow>}$(H-CH$2$CHO) = 92 $\pm$ 2 kcal mol$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$. This work explores the possibility of other thermal decomposition pathways, that result via C-H bond scission. We have used a resistively heated SiC tubular reactor with a 65 $\mu$sec residence time to study the thermal cracking of acetaldehyde. The decomposition products are identified by two independent techniques: 118.2 nm (10.487 eV) VUV photoionization mass spectroscopy and infrared absorption spectroscopy in a cryogenic matrix. The observed dissociation channels seem to be: enter{CH$3$CHO} + $\Delta \to$ CH$3$CO + H\ enter $\to$ CH$2$=CHOH\ enter $\to$ CH$2$=C=O\ enter $\to$ CH$3$ + HCO\