Railroad Forums 

Discussion of the past and present operations of the Long Island Rail Road.

Moderator: Liquidcamphor

 #5325  by timz
 
Over in the NJT forum, in the Arrow III thread, it says

"I got a cab ride last week with a friend's brother on a new set of LIRR M7's and the full-throttle acceleration was dramatic - you really had to hang on. We hit 115+ on the way to Babylon."

Assuming the engineer is retiring tomorrow, is this possible?

 #5402  by krispy
 
Nope, max speed possible on LI is 80 mph. Could most of the equipment do in excess of 80 hypothetically? Absolutely, and they may have had the M7's faster at the track out at Colorado or wherever they tested them.

The Feds set the standards for max authorized speeds throughout the country and these standards are dictated by type of rail and maintainance, signal systems and cab systems. They could raise the MAS, however the amount of crossings, curves and stations would limit places where the speed could be obtained and therefore would not justify the expense of upgrading the fleet, etc...

 #5582  by jayrmli
 
If the hogger tried it, the ASC would have shut him down.

Jay

 #5620  by thrdkilr
 
Krispy,
Why waste the money for trains that go over 80 mph? It would seem you could make them cheaper and more reliable if they made one that tops out at 80....

 #5716  by DutchRailnut
 
The M7 is rated at 100 mph and max speed on MNCR is set as such even in ATC cabinet.

 #5720  by Nasadowsk
 
I'm guessing they go for 100 for two reasons - a) in case they ever DO bump the MAS, and b) 'safety factor', i.e. the motors aren't spinning at their maximum design speed, but somewhat lower. It might also make the gearbox design a little easier.

 #5946  by DutchRailnut
 
The M7's were tested at higher speed 10% at Pueblo Co.
the design speed is 100 mph , so are M1 - M3 - M2 - M4 - M6 _ Bombardier shoreliners.
the testing at 10% is to allow a safety cusion for bad speedometers etc.
same way the Acela was tested at 165 plus mph. the design speed is 150.
nothing says they can not go faster, but if something happens the lawsuits would fly if it was more than 10% over designed speed.
as far as the suposed speeding with LIRR M7's this guy even if retireing would be a real A** H** cause id company takes him out of Service today he can not retire. you must be in service or disabled to retire.
they can even have criminal charges filled based on Federal rules.
little inside note the blackboxes (event recorders) are downloadable and diect accesable while train is in motion from several computers at roadforemans office and equipment desk.
 #6146  by N340SG
 
Dutchrailnut brings up more good points.
I also found this tidbit in the M-7 manual.
The speed sensors referred to are in the propulsion and wheel spin/slide system. The ATC speed sensors are a totally separate circuit.
So, even if the ATC was cut out, the indication from this info is that the propulsion system maxes out at 100 MPH anyway, via software control.

Scroll past the overtemperature section to the overspeed paragraph.

Image

If image fails to load:
http://members.aol.com/N340SG/speedlimit.jpg

 #6485  by Nasadowsk
 
Hey neat, instead of having a thermal probe, they just calculate the temperature on the motors on the fly :)

The E60s did this via a bizzare circuit over a few cards. Today, it's just a few lines of code :)

 #6677  by BMT
 
Well, if I recall correctly from a friend at LIRR, the M-7 signals a cab-based alarm alerting the Engineer when the train goes above 72 mph (IIRC). I also thought the brakes automatically kick in when you go above that speed.
 #6720  by SG
 
If you were lucky enough to get a ride in the cab WHY? would you tell half the world and then to add insult to injury you tell everybody you went 115.
Best thing you should have done was to keep it under your hat and your mouth SHUT!!!!!!!!!!!!!!!!!

 #6729  by N340SG
 
BMT,

Yes, all LIRR EMU cars have a Maximum Authorized Speed (MAS) of 80 MPH, enforced by the ATC system.
Above that, the brakes would apply automatically until train speed fell to below 80.
We were conceding that the ATC would have to be cut out to even stand a chance of doing over 80 MPH, let alone 100. But, there would/could still be other limits imposed.

 #6969  by bingdude
 
Maybe the speedometer was bad? Or maybe it was reading km/h...

115 Km/h would be about 70 MPH.

 #6999  by Nasadowsk
 
I think it's just the typical 'stretching' of the numbers that goes on that results in bizzare, and generally non possible figures:

125mph Arrows
130mph+ GG-1s
AEM-7s breaking the sound barrier
10 sec 1/4 miles out of a Honda Civic
8 sec 1/4 out of Japanese sportbikes
The 190mph, 600cc Kawasaki Ninja
Grandpa's rusty old steam loco 'cruising at 130 with power to spare'
614 doing 90 pulling 20 cars
The Empire State building swaying 10 feet each way

etc etc etc

See also: The old game of "Telephone"