Is there ever a problem communicting with manned helpers or DPU units in terrain where there are tunnels, curves or mountains?
Yes, but it usually not unexpected, you have the same problem at the same
place everytime, the DPU will keep on doing what it was doing before the
loss of signal for up to 90 minutes, the brake pipe can be used to knock
down power if needed, jackflash
when we use helpers…they are manned ones…and the head end controlls the speed… when your on the helper on the rear…you just keep shoving to make speed…and if the speed starts to speed up to where you might start to pu***he head end over the speed limit…you just notch off…but most of the time…your just wide open…and shoving…as far as tunels…when i was on the head end…i would tell the helper that the head end was starting into a tunel…and hit the counter when we start out of it…that gives me an idea that the helper on the rear is out of the tunel…
csx engineer
Today, the radio is a big help . However, in the old days, the helper engineer could here the two shorts of the whistle for starting, watch break line pressure and listen to other whistles to guide his responses.