Explain gyroscopic effect in trains or railways?

Question

Explain gyroscopic effect in trains or railways?

Answer 1

When a train goes around a curve it experiences centrifugal force, and so does anything or anyone travelling on it. Basically the momentum of the train tends to make it want to go in a straight line while the curve is pulling it round, so it will tend to lean towards the outside. The faster the train, the greater the force.

Railway operators deal with this in 2 ways: firstly, by restricting the speed on curves and secondly, by banking the track a few degrees into the curve - this is known as 'superelevation'.

Another recent innovation is the 'tilting train', i.e. a train that angles itself into the curve to counteract the centrifugal force pushing outwards.

British Rail built a tilting train called the 'Advanced Passenger Train' (APT) about 20 years ago but it was not a success. The more recent Italian 'Pendolino' train works better and there is now a British version operated by the Virgin Trains company.

Answer 2

No, YOU explain it!  Or try asking nicely.

Answer 3

I'm not quite sure the term "gyroscopic" is used properly here.

But, there is a phenomenon called "harmonic roll."  This occurs when trains are running on "jointed" rail, as opposed to CWR (continuous welded rail) aka, "ribbon rail."

What happens is each time a car or engine's truck passes over the joint, it takes a slight dip to that side.  When it comes to the next joint on the opposite side, it takes a dip in that direction.  If allowed to continue, the oscillation becomes greater and greater and can result in over-turned equipment.  This phenomenon is at its worst when the train is traveling at a speed of 15 MPH.

Is this what you meant?