[PRCo] Re: Drum__Brakes_--_All-Electrics,__etc........

[Fred Schneider]

I can related.  At least with a bus you can find something to  
sideswipe to slow your momentum.   With a rail vehicle all you can do  
is wind up the hand brakes and blow the horn or hang on the bell and  
hope you don't get injured.   And if you do what you want the  
passengers to do ... lay down in the rear of the car ... you'll be in  
court for not going down with the ship.


On May 27, 2007, at 7:45 PM, Herb Brannon wrote:

> Maybe it was just a bad dream then. I know, I was there in the  
> operators seat. Whatever the trucks, the specs, the engineers  
> drawings, the claims of Transit Reserarch Corp., etc. the brakes  
> failed and the car glided (it was not a 50mph runaway) all the way  
> to the bottom of the hill. It was then pushed around downtown and  
> back to SHJct by another car. But then 1727 should not have crashed  
> either. That car was heading for disaster almost a decade before it  
> finally did itself in. The cars had all seen heavy usage and  
> PATransit was trying to keep them going as long as they could.  
> SKYBUS was a dead subject and the cars had to keep operating. Many  
> modifications and "experiments" along with rebuilds (mostly  
> "cosmetic", but "mechanical" to the point that the operation of the  
> vehicle might have been changed) caused many strange mechanical  
> happenings that were never fully discussed with the general public,  
> the press, or the railfans. I remember that incident quite well, it  
> was the
>  only time I came close to being scared. I don't scare easily,  
> believe me, I don't. That trip down the hill was as close as I have  
> come to being really scared.
> Jim Holland <PRCoPCC at P-R-Co.com> wrote:  Herb Brannon wrote:
> .
>> When mechanical 'things' (in this case a 1945 PCC streetcar, still
>> operating in 1975-76) get to a certain age, like humans, they  
>> start to
>> fall apart. Yes, it was the "Spirit of '76" car, and it had a bad air
>> leak. It would not have mattered if it would have had every type of
>> air applied brake known to mankind, it still would not have stopped
>> without any air pressure to apply the brakes. That brake system (air
>> applied/spring release), in my opinion, was one of the more stupid
>> systems devised. Couldn't at least one of the scores of engineers
>> working on the PCC project thought far enough to realize that a  
>> spring
>> applied/air released system would have been safer ???? They thought
>> enough to put a 'hand brake' on the car, why not a "fail safe"  
>> braking
>> system?
> .
>> Boris Cefer wrote: Are you sure, Herb? 1776 was
>> formerly an interurban car with B-3 trucks and spring-applied drum
>> brakes with air actuators (pressure-releasing).
>>
>> B
> .
> As Boris Mentioned, The Bicentennial Car 1776 is ex-1616 and is thus
> equipped with B3 trucks. ALL PRCo B3 trucks are *_Spring-Applied_*
> Drum Brakes so a loss of air pressure with 1776_ex-1616 should have
> caused the drums to set up automatically --- i.e., air pressure is Not
> Used to stop ({[pat]}) 1601s renumbered as 1776-1781 --- Springs apply
> the brakes on these cars!!
> .
> Chust as a reminder.......
> .
> .......This is an ImPerfect World
> .
> In Fact --- EVERYTHING and _EVERYONE_ is Very Far From Perfect.
> .
> .
> That being said, the PCC is Still An Engineering Marvel and was Very
> Well Suited for the job it had to perform. Even into the 1950s the PCC
> could outpace the average automobile on the road from a dead stop. The
> PCC books indicate that the accident rate went way down with PCCs as
> compared to older conventional cars because of the increased  
> performance
> and in spite of the Increased Speed of the PCC --- the standard PRCo
> low-floor cars had a top speed of only 25-mph until many were rebuilt
> for speeds comparable to the PCC.
> .
> .
> The Hand Brake was to compensate for the lack of Fail Safe as were the
> track brakes --- get the car stopped using track brakes // hand brake,
> pop the dead man to keep the track brakes applied, jump out of the car
> and chock it! Loss of Air Pressure is an occasional & UnUsual failure,
> not routine, and the air gauge should give the op indication that a  
> loss
> is occurring so he can Still Safely Stop The Car before total loss. I
> rode the cars All The Time and Never experienced an air failure and
> remember Only One Operator mentioning such.
> .
> As Schneider mentions, the All-Electrics with spring applied drums are
> fail safe --- but *_Apparently_* Not All Of Them. The ex-TTC, ex-KCPS
> cars that came to SF during subway construction were GE with GE brake
> actuators and am told that when the MG is shut off, so are the drum
> brakes and the car will roll on a hill. Thus the flange marks on 30th
> from Judah to Irving where a dead car was spotted and ran away! I
> operated these cars but never shut down the MG except in the yard  
> so am
> not all that familiar with them. They were Very Smooth Operating cars
> as compared to Muni --- brakes felt Very Soft and as if the car would
> never stop but they stopped Just As Fast as a Muni car but Much More
> Smoothly.
> .
> .
> PRCo:::::::
> .
> 100, 1000--1199 --- Air-Applied, Spring Released Wheel Tread Brake  
> Shoes
> .
> 1200--1299 --- Spring-Applied, Air Released Wheel Tread Brake Shoes.
> Many 12s had brake shoes removed and drums applied. Cars with drums  
> had
> a tendency to roll back when stopping upgrade. Thought Izzy Reichert
> was going to have an heart attack when that happened to him on the
> 42-Dormont!
> .
> 1400--1564 --- Air-Applied, Spring Released Wheel Tread Brake Shoes.
> Some converted to drums; these cars Not Plagued with slippage like  
> the 12s.
> .
> 1600 --- All-Electric
> .
> 1601--1699 --- __AS__DELIVERED__ Air-Applied, Spring Released _DRUM_
> brakes --- extended range dynamics.
> .
> ..........For Those 1601s Converted to Interurbans with B3s the Drums
> are Spring-Applied, Air-Released! Remember___ 1613 and 1614 had
> experimental B3s --- believe that these were Spring-Applied - Boris??
> But Both 1613 and 1614 had B2s reinstalled in the 1950s and it is
> *_Presumed_* that they reverted to air-applied, spring released drums.
> .
> 1700--1799 --- All-Electric.
> .
> It always *_Seemed_* to me that the 1601-Interurbans were never  
> going to
> stop but they did and probably just as good as any other car (possibly
> not unlike the ex-KCPS cars in SF!) But the 1601-City Cars *_NEVER_*
> gave such an impression --- they were peppy, powerful cars!!
> .
> .
> .
> Jim__Holland
>
>
>
>
> Rise Up -- Go Cavs
>   Herb Brannon
>
>
>