  Saturn's moon Titan possesses stratospheric zonal winds that places it among
a sparse class of planetary bodies known to have superrotation in their
atmospheres. Few measurements have been made of these speeds in the upper
stratosphere, leaving their seasonal variations still not well understood. We
examined observations made with the extended Submillimeter Array (eSMA) in 2009
March (L\textsubscript{s}=355\textdegree{}) and 2010 February
(L\textsubscript{s}=5\textdegree{}), shortly before and after Titan's northern
spring equinox. Cassini observations and atmospheric models find equinoctial
periods to be especially dynamic. Zonal wind calculations, derived from the
Doppler frequency shift of CH\textsubscript{3}CN near 349.4 GHz, yielded speeds
of 128 $\pm$ 27 m s\textsuperscript{-1} in 2009 and 209 $\pm$ 48 m
s\textsuperscript{-1} in 2010. We estimated the measured emission to originate
from vertical altitudes of $336^{+112}_{-88}$ kilometers, equivalent to
pressures of $3.8^{+19.2}_{-3.4}$ Pa, commensurate with Titan's upper
stratosphere/lower mesosphere. This suggests a possible increase in zonal
speeds during this period. The results are then compared to those from previous
Cassini-inferred and direct-interferometric observations of winds, as well as
general circulation model simulations, to form a more complete picture of the
seasonal cycle of stratospheric zonal winds.
