BNSF signal question

[ndbprr]

Was at a company in Lemont Illinois this morning about four miles north of Joliet on the old ATSF main. A westbound train of piggybacks heading for joliet was proceeding on the righthand track in normal fashion BUT the signal on the eastound track was blinking yellow until it passed. It was a single signal head and appeared to be a block occupancy signal. Why was it blinking?

[jimrice4449]

I haven't worked for the BN since 1988 so this might not be current, but the flashing yellow signal is Medium Approach and indicates that the next signal is yellow (approach). The Midium Approach means "proceed at track speed prepared to pass next signal at not more that 40 MPH."

[Anonymous]

QUOTE: Originally posted by jimrice4449

I haven't worked for the BN since 1988 so this might not be current, but the flashing yellow signal is Medium Approach and indicates that the next signal is yellow (approach). The Midium Approach means "proceed at track speed prepared to pass next signal at not more that 40 MPH."

Your info is very correct sir. On the UP's East West line in Iowa,There line side Signals do the same thing too.