in these modern times an observer with an inexpensive radio scanner can listen in to the company channels all day.  and night.  here at the farm we do (at least when we're home).  but sometimes we do watch, and even try to help out when we can. 

so it came to pass that one day we heard a Q416 (Rocky Mount - Willard manifest freight) nearby, consulting with the AU dispatcher and the CSX mechanical desk about a problem with their second unit, which had experienced a catastrophic air compressor failure.  the crew reported "parts on the walkway and train air exhausting through the unit".  the decision was to cut the train for our road crossing and set out the bad order locomotive at the fairgrounds siding. 

after the cut was made we overheard the conductor telling his engineer he was a 20 minute walk from the head end (through a downpour and with slippery conditions along the track).  so we set off in the truck to intercept his soggy trek and inquire whether he would like a lift up the track (he would).  these photos show what happened. 

with the train cut in two to clear the grade crossing back in Washington Grove, the next task was for the units to detach from the train and run light up to the fairgrounds siding.
the units have gotten to the fairgrounds switch; the third unit (visible in the distance) has been left on the main while the first unit shoves the second one into the siding.  its problems were not confined to the air compressor: the brake cylinder for the no. 6 axle was stuck, locking the wheel in place.  all the more reason to set off that broken toaster and let the mechanical department deal with it.
with the malefactor set off, shut down, locked up, its wheels chocked, the gate locked, the derail set and the switch properly lined, it's time for the first unit to run back to where the second one was waiting.  in the far distance the Ward signal is illuminated; hot intermodal Q139 (Portsmouth - Cumberland) is approaching on track two.
the coupling has been made so now it's time to attach the air hoses, jumper cables and walkway chains.
the remaining locomotives back up against and couple to the first half of their train.
back at the grade crossing in Washington Grove, the conductor rides the cut as the train is reassembled.
making the join, attaching the air hoses and opening the angle cock.  while an eastbound D742 (Brunswick - Benning) coal drag passes on track two, the engineer pulls forward to stretch out the slack and ... BANG ... there goes the air.  it seems the pin didn't drop the first time around, so the steps are repeated and the second time it holds.  good.  time to run the conductor back to the head end so they can be on their way.
Q416 is on the move again.  the two big EMDs can handle the train without their ailing counterpart from Erie.  note:  the vertical streaks visible in the image look like seed pods hanging from the trees but actually represent water dripping from the overhang of the old B&O Gaithersburg freight house, now a museum.
Q416 starts to pick up speed as it heads past the Gaithersburg passenger station on its way to Cumberland.  the crew is unlikely to make it that far on their hours of service and will probably be relieved (in more than one sense of the word) at Brunswick.