Burner Malfunction and Ballast Management
During a flight at 1500 ft, the main burner flame becomes weak and yellow, and the pilot notices a drop in cylinder pressure on the gauge. The balloon is carrying 8 sandbags of 15 kg each as ballast. Ambient temperature is 28°C, and the balloon is near its maximum permitted take-off mass. The pilot has a backup burner and a fuel line cross-feed. The landing area below is a large harvested field, but a line of trees lies 500 m to the west. The pilot has 60 minutes of fuel remaining and the nearest suitable alternate is 12 km away.
1. Diagnose the likely cause of the weak yellow flame and describe the immediate actions.
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A weak yellow flame with falling cylinder pressure suggests fuel starvation or a regulator problem, not simply a cold cylinder. Possible causes include a blocked or partially closed valve, a regulator fault, or a cylinder that is nearly empty. The pilot should first check the valve position and the cross-feed, then switch to the backup burner if the main burner does not respond. If the flame remains poor, the pilot should assume reduced climb capability and plan to land. The pilot should not attempt to climb aggressively, because a weak flame may not provide enough heat to maintain altitude. The priority is to maintain control and select a landing area while the balloon is still manageable.
2. Explain how ballast should be used in this situation and whether jettisoning ballast is appropriate.
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Ballast is used to control altitude and to compensate for cooling or for loss of lift. With a weak burner, the pilot may need to jettison ballast to maintain altitude, but doing so near maximum mass reduces the margin for a safe landing. The pilot should jettison only the amount needed to establish a stable descent or to clear the tree line, and should keep at least two sandbags for the final approach. Dropping ballast over the harvested field is preferable to dropping it near the trees or over people. Because the balloon is near maximum mass, the pilot should plan a longer, flatter approach and avoid a high descent rate. If the burner recovers, ballast should be conserved.
3. Given the 500 m tree line and the 12 km alternate, decide on a landing plan and justify it.
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The tree line 500 m west is the main hazard. With a weak burner, the pilot cannot rely on climbing over the trees, so the landing should be made in the open field to the east or south, away from the trees. The 12 km alternate is too far to reach safely with uncertain burner performance, so the pilot should land in the field while control is assured. The approach should be planned with a gentle descent, using ballast only if needed to clear obstacles, and the pilot should brief any passengers. The decision to land early is justified because a burner fault can worsen rapidly, and the field offers a large, unobstructed area.