This maybe a stupid question?

[boston&maine]

I noticed on a webcam just now a loooong trin of coal carriers it was being pulled by 3 UP engines BUT at the end of the train was another UP engine pushing. Can they sychronize the speeds that close, because if they can't that has got to be a big risk.

[Railphotog]

The only stupid question is the one not asked!

Trains have been using pusher engines at the rear for ages, was quite common with steam engines that did not have the power of modern diesels. Some long trains even have helpers mid train, but these are remotely controlled by the lead engines.

[sushob]

If you ever have a chance to visit Horseshoe Curve (Altoona, PA area), nearly every train will have at least one helper pusing from the rear. They simply can't get up the hill any other way.

[NWR #200]

Depending on where it was, it could have been manned, or a DPU, (Distributed Power Unit, aka remotely MU'd to the lead loco)

[Steve B]

I missed the end of steam by a long way in the states but i love to watch old films of helper service trains, the whistle signals between lead engines and the rear helper facinated me, great stuff.

[boston&maine]

Your right about stupid answers thanks for reminding me. Remote control is the answer, as the engineer increases speed on his engine the others do it also. Makes sense.