Editing Streamliner (section)

=== Streetcars and high-speed interurbans ===
[[File:San Francisco F line streetcars at Jones.jpg|thumb|right|upright=1.0|Three historic PCC streetcars on [[San Francisco]]'s [[F Market & Wharves]] electric trolley line in 2003]]

Early versions of the [[PCC streetcar|PCC (Presidents’ Conference Committee) streetcars]] were referred to as ''Streamliners'' in North America. However, [[Aerodynamics|aerodynamic]] research appeared much earlier on the [[interurban]] scene, i.e. among the forerunners of the recent [[light rail]]. In 1905, the Electric Railway Test Commission started a series of test runs to develop a carbody design that would reduce wind resistance at high speeds.

Vestibule sections of different shapes were suspended independent of the carbody, with a dynamometer to measure the resistance of each. Over 200 test runs were made at speeds up to {{cvt|70|mph|km/h|0}} with parabolic, wedge, standard, and flat vestibule ends.

[[Image:Philadelphia & Western Railway 206.jpg|thumb|right|A late model '' Brill Bullet'' from the Philadelphia & Western Railway on display at the [[Electric City Trolley Museum]] in Scranton, Pennsylvania, in 2003]]

The test results indicated that a parabolic-shaped front end reduced wind resistance at high speeds below that of the conventional rounded profile. However, with that time's heavy railcars and moderate speeds, no significant operating economies were realized. Streamlining was discarded for another quarter-century.<ref>Middleton 1961, pp. 65–66</ref>

From the 1920s, however, stronger alloys, lightweight metals, and better design were all used to reduce carbody weight—which in turn permitted the use of smaller bogies and motors with corresponding economies in power consumption. In 1922, the G. C. Kuhlman Car Company built ten lightweight cars for the Western Ohio Railway.<ref>Middleton 1961, pp. 62–63</ref>

After an elaborate [[wind tunnel]] investigation, the first in the railway industry,<ref>{{cite web|first=Mike|last=Szilagyi|url=http://www.phillytrolley.org/philwest.html|title=P & W High-Speed Line|work=Philadelphia Trolley Tracks|access-date=4 June 2021|archive-url=https://web.archive.org/web/20210211120948/http://www.phillytrolley.org/philwest.html|archive-date=11 February 2021|url-status=live}}</ref> the J. G. Brill Company made in 1931 its first [[Bullet (interurban)|Bullet]] railcars, capable to speeds above {{cvt|90|mph|km/h}}.<ref>Middleton 1961, pp. 69–70</ref> With 52 seats, they weighed only 26 tons.{{clarify|date=September 2024|reason=Short tons?}} Some remained in use for almost 60 years.