Break away cabs on EMD E and F units?

This is a detached view from across the Atlantic.

The determining differences between the frames of a diesel-electric locomotive and a steam locomotive are dictated by nature of the driving equipment. In the case of a diesel-electric, nose suspended motors on the trucks and a diesel-electric generator/alternator set above the chassis.

This alone precludes the use of deep bar or plate frames. (Steam locomotives did not fold up in the middle when involved in high speed accidents).

The main strength component of a diesel-electric locomotive is its relatively shallow underframe. It will achieve some benefit to its 'beam strength' from the motor/generator unit connected to it, but this is reduced by virtue of the connection being made via flexible mountings.

The EMD 'F' locos have a bridge style truss frame above the underframe to give it increased beam strength, and also to have something to attach the panelling to.

The weak point lay just to the rear of the driving cab where the top framing was discontinuous because of the lower level of the hood. The vertical member at this point is not properly diagonally braced and this is where one would expect a failure in bending in the event of excessive compression load on the chassis to take place. It is doubtful if this was by design for safety, it is much more likely to be for appearance sake, following on from the GG1s in which Loewy had a hand and which received a great deal of appreciative comment.

On the subject of 'torpedoes' or as we call them over here 'detonators', we still have them in the UK as their use is written into the railways operating handbook. In particular they are deployed for the protection of track workers. There are also specific requirements for the sound insulation of locomotive cabs to not be so good that engine crews would not hear the detonators.

I would be surprised if similar Federal rules are not also in place in the US for class 1 railroads at least. It could be argued that their use could be extended, possibly to the prevention of trains over-running passing loops. Radio communication is fine and dandy when the train crews are awake, but this has not always been the case, the Hinton head on crash is a case in point. There is no doubt that a loud explosion under one's feet concentrates the mind wonderfully !

Edited for a 'typo'.

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RE:

Break away cabs on EMD E and F units?

For anyone well up on EMD E and F units: saw a rather frightful picture last night of an F unit slamming into a switcher. not pretty ofcourse. it was on a curve so the F unit fell to her side to the outside of the curve. but not before "breaking" in half right behind the cab. the picture...

The torpedo lives. The Es and Fs, not so much.

But this is true. I have in my collection several derailments, collisions, etc., the aftermath caught on film. The F units did have a tendency to break behind the cab, turning them into an "A" frame in a collision. Crew protection has been at a low all along, so it probably was a happy albeit unintended consequence.

The best example I have is a corn field meet between an F unit consist and a steam switch engine at the far west end of Roseville yard at a place called "Antelope," circa 1952-ish. The head end crew of an east train fell asleep, very easy to do, and ran into the yard and ran into the yard engine. Always a handsome loco to begin with, even the major inverted 45 degree "V" bend looked appropriate for an F unit in Black Widow paint. Actually it was a very conscientious and well known, well respected engineer at the throttle. A union official, a BLE (Brotherhood of Locomotive Engineers) Local Chairman.

Can't remember the name for the life of me... right on the tip of my tongue...

You got any ideas, Andy?

No, none of the class 1's hvae F or E-units that they use in freight service. However, a couple class 1's, including CP & NS do own active F-units that are used for business trains or other special passenger trains, such as CP's Royal Canadian Pacific, which is pulled by F-units.

I seem to recall a reference in "Trains" stating that these were designed to buckle right behind the cab in order to protect the crew in cases of head-on collisions. Apparently, the buckling was intended to absorb energy that otherwise might crush the cab. I can see how the buckling might appear to be a design flaw in the form of a weakness in the frame that allows the buckling. But my understanding is that it was an intentional design feature, kind of like how a fuse is the weakest link for the purpose of protecting the rest of the circuit.

Bob no ideas come to mind on that gentleman's name.My dad might remember.I'll ask him when i talk to him.As for the E and F units i don't know why they did that.My guess is that there was a flaw in the design of the cab.Possibly the wider body(covered wagon style)allowed the car body to move too far in the event of blunt trauma before it hit the engine block.Then it just sheared it off.That's purely a guess on my part.As for torpedoes we don't use them anymore.I haven't seen a torpedo on an engine(or anywhere else)in years.As with many things on the railroad the pinhead lawyers got involved and decided we were just too stupid to be in possession of explosive devices lol.

It was by design, to dissipate the energy in a crash.

I recall seeing a photo of an E7 (SAL?) which had collided with something, and the engine broke in two behind the cab. The caption indicated this was a design feature.

and yes, torpedoes are still used, but radio communication is so much better,

the "need" for them has been reduced.