The main reason we use airplanes to transport missionaries in the jungle is because they fly
quickly! Traveling by river is about 15 miles per hour. Walking is maybe 3 mph. But flying, that is much quicker. We usually flight plan for 120 mph in the float plane and 135 mph in the wheel plane. However, just like like a boat traveling on a river, there are air currents and winds which help speed up or slow down the speed of the airplane over the ground. Here are a few shots during flight. Notice the airspeed indicator reads the same, about 110 (its in the top right hand corner, with the green arc). The ground speed on the GPS units tells a very different story!
Sometimes we can use the winds to our advantage. Down low there is usually less wind so if we are flying against the wind we will try to stay low. But up higher the winds are stronger so if we are going with the wind it saves times to climb higher and get the extra "push". The passengers never notice but I am happy if I can save them 10 minutes on a flight. Thats just 10 more minutes of flying they don't have to pay for.