Vintage, 1930s Flexible Flyer, Wood and Metal Snow Sled, No. 3G, 48"

Description

I'm thinking this is a "G" series
First Series
:  From after 1889 to about 1908, up to 6 sizes with flat runners.  At some point a goose neck runner came into being that extended the length of the runner on the ice.
B Series
:  About 1908 to 1914, up to 6 sizes with grooved runners.  This was the last series with a wooden bumper and wooden side rails all the way forward.
C Series
:  From 1915 to about 1928, this series utilized an all steel front end initiated on the Tuxedo Racer a few years before.  Part way through the series the logo on the center of the sled was modified.  In 1921 the eagle in the logo started carrying a sled whereas before it was an American shield.
E Series
:  At some point an E series was made that, as far as we can tell, was identical to the earlier C Series.  We guess that it was short lived, around 1928.  Some Racer models have been observed with a D Series on them as well, but these two letters of the series are not well established.
F Series
:  Around 1928 an articulated bumper came out in the F models.  We have observed F sleds both with the two piece bumper joined in the middle, and with the two pieces covered by a single piece.  This latter arrangement became the permanent bumper for all subsequent models and thus the rare F model with out the single piece over the top can be seen as a significant new development. This series also inaugurated the simple diamond patterns on the deck and handle.
G Series
:  Estimated from about 1930 to 1935, the G series implemented the three piece bumper with the diamond pattern, and at some point added a "safety" end to the end of the runner.  While the metal bumper continued the straight yellow line seen since 1915, later G models came out with a pair of diagonal lines.  We assume that the diagonal lines coexisted with the Airline series.
Airline Series
:  The Airline sleds came out in 1935 with the ends of the runners turned back to the top of the last cross support.  This major change was meant to prevent other sledders from impaling themselves on the sharp end of another's sled when running into them.  There were numerous Airline models, each with its own name: Ace (37"); Pilot (41"); Patrol (44"); Pursuit (47"); Junior (51"); Chief (55"); Racer (60"); Cruiser (65"); and (108").  The Airline names were eventually dropped with a number/letter replacing them, but with the same lengths as before, and the length being the model number.