How a hot-air balloon actually flies
A hot-air balloon flies on one simple principle: hot air rises. A propane burner heats the air inside the giant nylon envelope; that warm air is lighter than the cooler air outside, so the whole balloon becomes buoyant and lifts off — exactly like a bubble rising through water.
The pilot controls only altitude — firing the burner to climb, venting air to descend. There is no steering wheel. Direction comes from the wind: by climbing or dropping into layers of air moving at different speeds and angles, an experienced pilot "steers" the balloon across the valleys. That is why calm, predictable winds matter so much.