The Wright brothers’ patent: "Plane stabilized in roll by a pendulum" (US Patent no. 1,075,533). It seems impossible.

"The pendulum rocket fallacy is a common fundamental misunderstanding of the mechanics of rocket flight and how rockets remain on a stable trajectory." Robert Goddard fell into this trap as late as March 16, 1926 when he tested a liquid fuel rocket. The Wright brothers filed their US Patent no. 1,075,533 in February 1908,  tested the stabilizer in December 1913 and it worked flawlessly. Orville Wright even got a prize for his achievement (see the book below).

How is it possible? A pendulum with its pivot in an accelerated movement (like inside an airplane) does not tend to align to the vertical and can not be used as a reference like a gyroscope.

Is there another case when somebody succeed in stabilizing a plane in roll using a pendulum?

The 5 Wright brothers' patents:
- The US patent no. 821,393, granted on May 22, 1906, and its foreign versions, claim: (1) the method of wing warping, in particular, and the ailerons (already invented in 1868 by M. P. W. Boulton), in general, for stabilizing an aeroplane type machine in roll, (2) a movable vertical tail aimed at counteracting the adverse yaw generated by twisting the main wings, (3) a flexible front elevator for maintaining the pitch stability of the same machine, (4) various constructive details.
- The French patent no. 384.124, published on March 30, 1908, and its foreign versions, claim two more vertical rudders, placed in front of the main wings, one fixed and the other mobile. They were aimed at better counteracting the adverse yaw.
- The French patent no. 384.125, published on March 30, 1908, and its foreign versions, claim two additional vertical rudders, placed close to the tips of the main wings. Their purpose was also for eliminating the adverse yaw.
-> The US Patent no. 1,075,533, granted on October 14, 1913, and its foreign versions, claim automatic stabilization mechanisms: in roll, driven by a pendulum, and in pitch, governed by wind vanes (two models are proposed).
- The US patent no. 908,929 - “Mechanism for Flexing the Rudder of a Flying Machine or the Like”, granted on January 5, 1909, and its foreign versions, claim systems aimed at flexing the rudders of an aeroplane type machine for the purpose of modifying their lift.

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The book contains the patents of the Wright brothers in full.