In this lecture Dr. Ir. J. Hoekstra continues with horizontal flight performance starting with the maximum range problem. Last lecture the condition was found at which you achieve maximum range, which will now be translated to properties you have control over in flight. The next subject is an environmental exploration where the fuel consumption of aircraft is compared with that of cars. The maximum endurance of an aircraft is explored next, which can be calculated in a similar manner to the maximum range, and finally speed stability of aircraft is considered. Dr. Ir. Hoekstra then continues ahead with climbing flight, starting with a derivation for the maximum climbing rate, which results in the power equation. Finally the gliding performance of an aircraft is considered where we find an expression for the maximum that can be time spent gliding.