Temperature control during the flight
The candles or wrappers from hot air balloons of latest generation are made with various fibers Nylon.
The nature of Nylon with meteorological parameters and different possible speeds, determine the temperature range for use in maintenance and flight manuals:
To control the internal temperature, the balloon takes 2 devices acting as temperature indicator:
Flag: A temperature indicator is welded to a flag made from the same fiber than the balloon. It's placed in the top of the sail. When the temperature exceeds 125ºC, the flag is released, warning to the driver of overheating.
Temperature labels: the label allows knowing the process of temperature rise that was produced during the flight. Each one of the 2 labels of 8 points that has 16 possible readings is used. Labels recorded temperature rise during the flight. If the balloon is overheated, will have to record the readings of the labels in the flight log, for - if it's necessary - examine later the balloon. It's also detailed in the manuals how to act if labels come off. If this happens could also be indicative of overheating. In this case, it is obliged to try to lower the temperature immediately and proceed to the descent and landing maneuvers.
In this application the references are THERMAX 8 levels Range B (71-110ºC) and THERMAX 8 Levels Range C (116-154ºC).
Once finished the flight, labels show the maximum temperature reached. In case of accident, Irreversible labels can indicate if it has been a human error, faulty design...
Irreversible labels THERMAX are used in this purpose for more than 10 years ago.