Summary: Rudder Tab certification
Project Name: Rudder Tab On A-1 Series Blimps
Client: American Blimp Company
Client Request: The client requested a fix to balance the aerodynamic torque created by an installed Lightsign on the left side of the blimp’s envelope.
Project Summary: We did the preliminary sizing for a fixed rudder tab and worked with ABC on the detail design. Fliegen Works developed the aerodynamic loads, produced a structural test proposal and then DER witnessed the tests. The design of a fixed tab on a Rudder of ABC A-1 series airships was a challenge since a number of engineering estimations were made. From minimal available blimp flight and aerodynamic data and old NACA data an analysis was performed to design a fixed rudder tab that biased the rudder to compensate for the unsymmetrical drag on the airship due to the Lightsign on one side of the airship. This was a major change to the type design by the type certificate holder.
Results: Successful flight testing, installation and approval of rudder tab on A-1 series blimp. Pilot force required to maintain straight flight reduced to acceptable levels. Rather than complex CFD, a simple method combined with a little guesswork was applied. Minimal time and cost was required to produce the required results in this manner.