An ultralight aircraft [Figure 1-20] is referred to as a vehicle because the FAA does not govern it if it:
• Is used or intended to be used by a single occupant.
• Is used for recreation or sport purposes.
• Does not have an airworthiness certificate.
• If unpowered, weighs less than 155 pounds.
• If powered, weighs less than 254 pounds empty weight, excluding floats and safety devices that are intended for deployment in a potentially catastrophic situation.
• Has a fuel capacity not exceeding 5 gallons.
• Is not capable of more than 55 knots calibrated airspeed at full power in level flight.
• Has a power-off stall speed, which does not exceed 24 knots calibrated airspeed.
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