crashworthiness

1) Neither have cabs any wider than any other diesel unit!

2) Any and all diesel manufacturers & remanufactures have to comply with applicable AAR/FRA requirements.

Probably better than a steamer.

Hot,

That's not what I'm asking/after. Very few, if any, things are equal; I'm simply asking...who's is better, re: crashworthiness?

There are some noticeable differences in GE's and EMD's designs; one being, EMD's model has a somewhat blunter face/front end; which, probably, would react differently in a collision...

Rick

Well, I'm reminded of a paticular "crash" on the N&W Rwy, shortly after they received the massive order of GP9s from EMD. What the  cause was, the poor GP9 wound up with a seriously bent under frame as well as other serious damage. The N&W folks where pretty up set, and fired off a letter to EMD, essentially wanting to know WHY the under frame bent. I don't remember who authored the response letter from EMD, but the gist of the letter wound up being, "If you will please give us EXACT engineer specifics of your next wreck, we will be more than happy to design a locomotive to with stand those specific parameters.".

Thus, my point being; no one can OBJECTIVELY state which builder is "better", without knowing EXACTLY how you plan on crashing you locomotive! 

Each collision has different dynamics associated with it.  As long as the locomotive's construction conforms to current collision standards, no one builder's cab will be better than the other's in a collision.

Rusty

Rusty,

Again, whose is, all around, better? Your dancing around the question, Rusty, or you don't know the answer(there's nothing wrong with not knowing). I'm trying to find someone who does...

Rick

Automobiles all conform to government rules and regulations, but there are certainly differences between automobiles when it comes to crashing. As to whether those differences have been documented when it comes to locomotives is another question.

Not quite answering the question, but there are a number of youtube videos that show an EMD locomotive being crash tested. Here is a link to one of those videos:

http://www.youtube.com/watch?v=FM1_HVhZMwI

Actually you are NOT!  You are simply creating a non-ending "discussion", which does NOT have an answer, and you can thus keep the "discussion" going.

Rick, obviously the meaning of the sentence  "As long as the locomotive's construction conforms to current collision standards, no one builder's cab will be better than the other's in a collision."  appears to elude you.

Plus, the nose or cab is not the first point of contact, the anti-climber, pliot and the coupler are.  These will have more of an effect in initially deflecting the "target" as it were, then the nose.

Simply put, GE will say theirs is best, EMD will say their's is best.

Rusty

WBC's response acknowledges what I'm after; I'm looking for actual crash test results, not personal theories/preferences.

Rick

Perhaps these links to documentation will help to give you some useful information. But I agree with Hot Water & Rusty, there is no simple answer to your question as both meet safety standards, and all accidents involve different dynamics.

http://ntl.bts.gov/lib/43000/4...ve_Dynamic_Test3.pdf

And for more comprehensive reading on the standards and regulations. http://www.gpo.gov/fdsys/pkg/C...e49-vol4-part229.xml

Rick, it is quite obvious that the knowledge that you seek is not available on this forum. You will have to research the topic yourself. Evidently the crashworthiness of rail equipment is studied. Perhaps here is a starting point:

http://www.volpe.dot.gov/coi/p...ive/crashworthy.html

There is, in all probability, a government report that addresses the questions you have about the differences in locomotive design and how each design functions in a variety of crash scenarios. 

Good luck

Thanks Nicole and WBC.

Some people value crash test results; it;s one of many pieces of useful information, re: the worthiness of something... it helps provide an informed opinion.

Rick

Crashworthiness design for a locomotive would be a tough design given the potential mass of the trains behind them.  For a nose to nose collision there are two issues the designer would have to address.  One is to decelerate the locomotive at a survuval rate, may be less than 4g.  This is done by having crush zones with continually increasing strength.  This will only work if the colliding locomotives stay in line with each other.  The other issue is what is called the secondary collision.  When the locomotive stops quickly the people inside continue moving at the locomotive's former speed.  At some point they hit something strong enough to stop them.  It is this second collision which results in most injuries.  The designer is going to try and manage the second collision by eliminating projections, hard spots, windows that pop out, etc.  The AAR addressed the secondary collision in there "clean cab" program many years ago.  Teheran FRA is still trying to address passenger car crashworthiness and has done little for locomotives.  I am sure both builders have addressed crashworthiness, but I doubt that this information is ever made public.

Thanks, David.

I have watched commercial airline crash tests before, on TV; they seem to offer valuable, usable information... for all concerned.

Rick

EMD and GE have to meet the same AAR/FRA requirements.  There is really no radical difference between the two so they should be equal in crashworthiness.  EMD and GE can only do so much with their design while trying to maintain some bit of individuality.  The angle of the nose is pretty similar between the two manufacturers.  Recent wrecks have had fatalities in both types of cabs.  Fire is a big problem and any cab is a death trap in that case.  Neither are perfect but are an improvement over the old cabs with the narrow noses. 

Now if you were to ask which one I feel safer in, as an engineer, I would guess EMD with their isolated cab. That is just an opinion mind you. 

Greg

Very timely post.  There is a thread on the new CP-GP20ECO.  Apparently the "C" signifying crashworthiness of the cab, frame, and fuel tank.  CP took delivery of several of these models.  Also apparently CP is also taking some SD40-2 and turning them into SD-30C's.  Really digging the long nose of the new GP20s.  Thanks for the info.

I'd rather take my chances in a GE over a newer EMD with the "Quiet Cab"... especially after the BNSF wreck in Iowa not that long ago.

CN_Hogger

What you see from the outside (i.e., the sheet metal nose and cab) is not what provides the primary collision protection.  The heavy collision posts are inside the nose, and they are about equal if EMD or GE.  They are there to prevent any equipment struck from coming over the top of the frame and cleaning off everything back to the electrical cabinet, which was possible with locomotives such as SD40 or GE Dash-7 or -8.  But you can't provide total protection.  If anything does get over the heavy collision posts, the cab can be torn apart.  The design of sheet metal won't matter.  However, this happens less often than it did before the use of North American cabs.

It makes a bigger difference what you run into -- not whether you are on board an EMD or a GE North American cab locomotive.  Any rail equipment that over-rides the nose collision posts can crush or remove the top part of the cab.

Diesel locomotive design conditions, including crashworthiness, are defined under the Code of Federal Regulations(CFR), Part 229. The FRA and Volpe Research Center in Washington,DC., are involved in establishing these standards not only for freight locomotive builders,GE and EM, but also for heavy passenger rail EMU's. Passenger rail EMU motor cars(powered) and trailer cars(non-powered) design requirements are defined in Part 229 and Part 238 of the CFR.

John

That's what I remembered when they went to the wide nose, and called it "wide cab".

There were comments in railroad magazines about collision posts in the wide nose. Nothing is perfect, but I would think you'd have a better chance in a wide nose cab.

I don't know why the wide nose cabs are called wide cabs, such as the CSX

AC44CW's, maybe they have thicker paint that the narrow cabs.

Ed

When I was a boy Engineer, I rode out a wreck on a GP35, and, because the geep's nose rode onto a flatcar and stopped pointing upward, nothing over-rode the front..

I was on a light helper engine drifting at about 30 MPH.  A train going the opposite direction, on the adjacent track at about the same speed, let the slack run in and buffed a couple of empty intermodal flats onto our track, right ahead of our engine.  The leading end of a flat lost its truck and dug in as it fell onto the track.  We rode up onto the first flat and stopped while several cars piled up around us as we rocked back and forth.  When I heard the other fellow's slack run in hard, I saw the derailment beginning, put the brake valve in Emergency, jumped out of the seat, and braced myself against the front cab wall.  We hit right after I braced myself and went from 30 to zero in about a car length.  I did not get a scratch, but everything seemed as though it went into slow motion while the rear part of the other train was shoving cars into the pileup.  After the other train quit piling cars into the wreck, the radio still worked, so I called the operator at San Bernardino to report the wreck.  The Trainmaster wanted me to go to the emergency room to be checked, but I just asked for a ride to the roundhouse so I could tie up and go home.  The other guy in the cab bumped his knee and milked it for everything he could get. 

That was one of my lucky days.  If we had not over-ridden the flatcar and aimed the nose upward at about 20 degrees, some of those other cars might have crushed the cab.

A while back, I read that one of the manufacturers used armor plating on the exterior of the cab, to minimize damage costs associated with a collision. The idea being that the armor plated unit would smash through whatever was in it's path, sustaining minimal damage.

I can't remember if it was a conventional or wide cab?

Rick

Great idea until one such loco crashes in to another that is equipped the same.  NS is equipping much of its power with their "Admiral Cab"....thicker steel, sharper angles ect.  Their new design weighs in at 12,500lbs vs. the original EMD design of 3,500lbs.

http://www.altoonaworks.info/rebuilds/admiralcab.html

Kind of sounds like manned, massive power chisels. I can see an armor plated unit winning out in a collision with rolling stock etc., but not another full size freight locomotive.

I imagine the front end of a locomotives platform does incredible damage, when it strikes something, at speed. I think EMD's isolated cabs could even be severed, in a collision involving significant striking force.

If ya saw the collision coming... what would you do - trust in your equipment and ride it out or bail out... at speed? I wouldn't want to have to make that choice.

Rick

Due to the secondary impacts in a wreck, has there been any thought of putting air bags in the locomotive cab.

However, in a high speed head on, there is too much mass in both trains to keep any cab intact.

How about a roof escape hatch?

Unmanned motive power wouldn't be popular with professional railroaders and their civilian fans; but, it would take care of crew safety issues and costs.

Rick

There have been lots of creative safety devices considered.  I recall one major railroad looking at a breakaway cab.  The problem with all these approaches is they need to work every time in a crash situation and never deploy inadvertently in a non crash situation.  A tall order for technology.  Without immunity from liability, active safety devices will be slow in coming.  But do not overlook the improvements that have been made.  Compare the cab of an unmodified GP-7 with a modern locomotive.  It would be interesting know what the Southern had to go through when they changed from long hood forward to short hood forward locomotives.

The only real locomotive cab that I have been in was a 3000hp SD40-3, with a conventional cab. It was spartan, inside, very basic... almost institutional looking. Painted metal walls and controls... not a good place to be in a high impact crash.

I liked it though, because I was told to take the wheel. It was a hot summer day and the engineer had to fight to get the window open. To be fair, the 6 axle was well past it's prime...

The pictures and videos I've seen of the modern wide cabs, look like an improvement over the cab I was in.

Rick

Again it is the type of collision as others have said.

Seeing the results of a UP rearender at 40MPH in Missouri years ago, the lead locomotive on a coal train hit a remote unit on a stopped coal train on a slight curve, that curve help the lead loco glance off and the cab reamained intack, crew survived. The remote lost it's engine, It was a massive wreck.

Seeing the the photos of the BNSF rearender up in Iowa, at maybe 18-20MPH, the rear flat car rode up over the loco frame and did unsurvivable damage to the cab.  

Those ariplane crash test are pretty neat.

 I think they do very limited locomotive crash tests at the FRA test grounds near Colorado Springs?. They do much more frieght car testing, especially tank cars.

Dan 

In the end, I think being part of a diligent crew, provides the best bang for the buck.

When the heavyweight's start flying, there's no sure thing.

Rick

quote:

It makes a bigger difference what you run into

Indeed! We were shown pictures of the unit that struck a loaded propane tank truck. It was not a pretty sight!