81-05-03 THE BALLOON WORKS: Amendment 39-4053. Applies to Firefly Models 5, 6, 6B, 7, 7B and 8-24 series hot air balloons equipped with Fire 2 auxiliary heaters incorporating The Balloon Works fuel tanks part numbers BW 3229-A through BW 3229-N and BW 3307-A through BW 3307-H, certificated in all categories.
Compliance required within the next 10 hours time in service after the effective date of this AD, unless already accomplished.
To prevent inadvertent operation of the Fire 2 heater system during a hard landing, even though the tank valve has been closed, accomplish the following:
Modify the Fire 2 fuel tank shut-off valve in accordance with The Balloon Works Service Bulletin B12 dated December 15, 1980, or later FAA approved revision, or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, Southern Region.
Make an appropriate maintenance record showing compliance with this AD.
This amendment becomes effective March 11, 1981.