The applicability of a simplified algorithm for estimating T-foil lift and drag at different scales and speeds is studied. The calculation results indicate that when the Reynolds number Re is on the order of 10 ⁵, the simplified algorithm has a high degree of agreement with the CFD numerical calculation results and has good applicability. When the Reynolds number Re increases from 10 ⁵ to 10 ⁶, the lift part of the simplified algorithm still applies, but the deviation between the drag part and the CFD results significantly increases, making it unable to guarantee applicability. The above calculation results have also been partially validated by the drag test results, and the current simplified algorithm for estimating lift and drag of T-foils urgently needs further updates and improvements.