Aircraft Instruments by Pallet page 282 figure 11.18(c) and (d)
Application depends on Velocity of engine exhaust gases.. High in jet so stagnation used where entry and exit holes are not in line, not equal in size, so gas is slowed and stagnated/sampledtyp response 1 to 2 seconds
Rapid responce in turbo prop with equal sized entry/exit holes diametrically opposite so gas flows straight over the hot junction so it responds rapidly.typ respnse time is 0.5 to 1 second