🚀 go-pugleaf

Scott M. Kozel wrote in message <36C637AC.276A@richmond.infi.net>...
>cpatz@ibm.net (C. P. Zilliacus) wrote:

>The 22-mile Virginia side was 65 mph, the Woodrow Wilson Bridge was 60
>mph, the 30 miles from MD 210 Indian Head Highway to MD 97 Georgia
>Avenue was 70 mph, the winding section through Rock Creek Park was 50
>mph, and thence to the Cabin John Bridge and across to Virginia was 60
>mph.  These speed limits seemed to match the design speed of the
>highway, based on horizontal and vertical curvature, and stopping sight
>distance.


As well as the average vehicle of the time, some one third of a century ago-
given the advancements automobiles in general regarding their tires. brakes
and suspensions.  Up to a certain point of traffic density, you can add 5-15
mph to the above pre-1973/4 speeds, as attested by the 60-70 mph traffic
speeds along the curvy sections of the Capital Beltway between Georgia
Avenue and Wisconsin Avenue, and 65-80 mph elsewhere.

Douglas A. Willinger
Takoma Park Highway Design Studio