Even though hot air balloons are relatively simple aircraft, there are some required instruments that the pilot uses while operating a hot air balloon. They include:

Altimeter: Displays the altitude of the balloon. This is most commonly set to display the altitude above sea level, but some pilots set theirs to read above ground level. Managing the altitude is important for many reasons including air traffic control, obeying regulations, and avoiding ground-based obstructions.

Rate of Climb/Descent: Also called a variometer, this indicates the speed at which the balloon is climbing or descending.

Envelope Temperature: The temperature of the air inside the balloon is controlled to avoid over temping the balloon which can damage the fabric and reduce the life of the balloon.

Fuel quantity: Fuel management is obviously important - it's not a good thing to run out of fuel regardless of the type of aircraft!

Fuel pressure: Most hot air balloon burners require a minimum fuel pressure to generate the heat rewuired for safe flight, so fuel pressure is monitored by the pilot.

Aircraft radio: An aircraft radio may or may not be required, depending on the airspace the balloon is operating in or near. Used to communicate with air traffic control and other aircraft.

GPS: While a GPS receiver is not required, some pilots like to take one to assist in navigation.