Re: Re: Approach to Sydney Central

[Hubert Lam <hubert@imap4.com>]

But a tangent can also be a straight line that touches a parabola at one point only, so from the
other assumption is that it is like a tangent to the straight track but that it is a
crossover/turnout. Correct me if I'm wrong, but an example of the tangential turnouts would be the
crossovers at Concord West, West Ryde (Up and Down Main North and North Suburban), and down suburban
Epping ?

TrackOrange@iFOURfreeSPAMM.co.nz got bored on Fri, 26 May 2000 10:13:52 GMT and so wrote the
following:
 
          On Fri, 26 May 2000 19:06:06 +1000, "Paul Cassar"
          <railroad2000@optusnet.com.au> wrote:
          
          >A tangential turnout is a high speed turnout. The switchers are not as high
          >as normal turnouts and are supported by a thicker switch plate.
          
          Tangent is a term used in track geometry. A tangent is a straight line
          which touches the circumference of a circle at one point only.
          
          The tangent point (TP) is where a simple (circular) curve joins the
          straight track. I think that straight track is called tangent track
          but after a quick look through some references I cannot confirm this.
          
          The common tangent point (CTP)  is where a transition curve joins the
          circular curve. I assume that it is called this because the two
          tangents are parallel at this point.
          
          Hence my guess ( and I emphasise that is what it is)  is that a
          tangential turnout is one with curved rather than straight switches.