# What thrust is used for thrust to weight ratio?

Performing some preliminary calculations for an aircraft design I have and was wondering what thrust I should use to calculate thrust to weight? The thrust calculations I have, vary due to speed (since in general force is a change in linear momentum) and so the faster the aircraft is traveling, the lower the thrust I have is. Should I use the initial thrust when the aircraft is initially accelerated, an average thrust of some sort or a different thrust estimate altogether?

These are two different equations I have used to estimate thrust (For propellers)