Would the PRR have had defect detectors in 1953?

[dehusman]

What is a ‘parkway outlet’ and why are the specific design details for them in S-241-K taken?

It appears to be a kind of conduit for the detector circuitry, probably made by the “Parkway Co.”.

[dehusman]

Why can the center rows of airbrake-hose segments be eliminated if the detectors detailed in S-241-K are installed, per the note for the snow guard?

The opposite. What the note says is if the detectors ARE installed per S-241-K the middle hoses should be installed.

Drawing S-241-K shows 5 detector loops, with one in the middle of the track. When they are installed like that, per that diagram, then the guard hoses have to be installed all across the tie.

That implies that there is an alternate drawing that only has 4 detector loops, and when that plan is used, since it doesn’t have the loop in the center of the track, it doesn’t need the hoses in the middle of the track.

[cv_acr]

I think in 1953 the “defect detectors” were primarily the railroad’s employees. If a train stopped a sidetrack for a meet, their crew would watch the train passing them and then signal to the caboose crew that everything was OK, or use hand signals to indicate a problem (like holding their nose to indicate a hotbox). Same thing would happen at stations, signal towers, crossing shantys, etc. Railroaders looking out for each other.

They still do that today, even with all the yard checks and automated hot box and dragging detectors.

If you listen to the radio scanner when two trains pass each other, or pass someone on the ground, you’ll head something like “Good on the {direction} side” as they give each other “rolling inspections” for shifted loads, loose strapping, visible running issues etc.