Pipe X length is shorter than the elevation change between Junction Y and Z

A Caution message in AFT Impulse

This caution alerts you to an inconsistency with the input data due to a pipe being defined with a length that is shorter than the elevation change between its connecting junctions. This may be an input error or a result of a junction which itself has an elevation change. If it is due to the junction having an elevation change, you can use different inlet and outlet elevations at the junction to resolve this.

In this situation, pressure loss along the pipe due to friction is calculated using the pipe length the user has defined while static head loss is determined using the elevation change the user has defined.