Protonated fluoroformic acid, FC(OH)2+, is produced in the gas phase upon dissociative ionization of ethyl fluoroformate, via FCOOCH2CH3.+ --> FC(OH)2+ + .CH=CH2 (McLafferty + 1 rearrangement). Sequential decomposition of FC(OH)2+ by loss of.H provides access to the radical cation FCOOH.+, from which neutral fluoroformic acid can be generated by neutralization. Reionization approximately 0.4 mus later shows that solitary fluoroformic acid represents a stable molecule with an appreciable barrier for dissociation to FH + CO2. This result is consistent with ab initio theory predictions and confirms that the spontaneous decay of FCOOH observed in condensed phases is an intermolecular, not intramolecular process. The major dissociations of cations FC(OH)2+ and FCOOH.+ involve cleavages of their F-C and C-OH bonds, ultimately leading to structurally characteristic losses of FH and H2O from FC(OH)2+ and of F. and .OH from FCOOH.+. The eliminations of FH and F. are associated with substantially larger reverse activation energies than the eliminations of H2O and .OH.