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It is well known that phosphor thermometry may be used in environments characterized by high brightness from blackbody background or combustion flames. The present work describes measurements performed inside an operating turbine engine. For this application, two thermographic phosphors were chosen to cover the expected temperature range. The first, Yttrium Oxide doped with Europium (Y2O3:Eu) has received much attention as a temperature-indicating material for higher temperature ranges. The second, Yttrium Vandidate doped with Thulium (YVO4:Tm) is relatively new, and was chosen for several reasons. First, it exhibits a bright emission line at 475 nm, which is much bluer than Y2O3:Eu line at 611 nm. Blackbody emission will have less effect on the detection of blue emission as opposed to the red. Second, YVO4:Tm also exhibits temperature dependence from at 100 oC to above 900 oC in the range not covered by Y2O3:Eu. This testing proved that temperature measurements are possible in this environment, given proper selection of the emission wavelength and temperature range. I