Nice bit of info!
Thanks, Sheldon
Jacks and chains used into 1960's but hitch was invented in mid-50's and eventually replaced them. Trailer Train introduced 85' cars with hitches in 1958
Article on NKP piggyback 1954 photo on page 4 show trailer being secured on flat car.
http://www.nkphts.org/empmags/1954julaug/piggyback_1.html
Drawing from Railway Age trade magazine
http://images.yuku.com.s3.amazonaws.com/image/jpeg/159365212fb60ebca7276504b4bcf5e41cb003d3.jpg
Article on model of 1950's Wabash piggyback
http://www.gatewaynmra.org/2015/modeling-1955-wabash-piggy-back-flat/
From http://cs.trains.com/mrr/f/11/p/247507/2760844.aspx#2760844
ATLANTIC CENTRAL on Wednesday, May 27, 2015 7:29 AM
"50's era piggyback is one of my primary modeling subjects, and my father worked in the trucking industry in that era, and worked for the SOUTHERN railroad in their piggyback operation in the early 60's.
A few general thoughts:
Cranes - fixed track or rubber tired, piggy packers, and such did not become common place until the very late 60's and early 70's.
Jockey tractors with two steering wheels, while rare, were used by a number of railroads.
Jockey tractors with half cabs and hydraulic fifth wheels were then and are now common in the trucking business - with or without the railroad connection. They include other features like different steering rates and slow speed gearing to make precission backing, even for long distances, very easy for a skilled driver. Many such tractors will not go over 25-35 MPH in any direction.
As piggy back traffic increased, railroads did build specialized yards with multiple short tracks to reduce the number of cars loaded from each ramp. This obviously speeded the loading and unloading process.
Piggy back flats continued to have bridge plates well into the 80's as many small terminals still used circus loading/unloading.
In the 50's trailers were typically 35' max, 40' trailers were not legal nation wide until '57 or '58?
The fifth wheel "hitch", invented late in '55, did not come into wide spread use until 1958 or so. But well into the 60's you could still fine trailers jacked and chained to flat cars.
While rarely modeled, a measuable percentage of early piggy back flats that carried a single 32' or 35' trailer were only 40' long. A number of railroads used underframes from obsolete 40' box cars to build such cars in their own shops.
The creation of TrailerTrain quickly brought standardization to the equipment and ended all the custom flat cars made in railroad home shops.
Different railroads saw piggyback in different ways at first. Some saw it as way to serve "off line" customers, some saw it as a way to get deeper into the "LCL" business, and some saw it as a way to simply compete with the trucks and/or partner with them. In the end it did all these things, but it would have done them sooner and better if not for foolish government regulations.
Based simply on safety and fuel economy they is little reason to have many long haul trucks on our highways, but because the government did not "get out of the way" until 1983, we still have a transportation infrastructure that includes long haul trucking.
Sheldon"
Regarding cars with hitches Atlantic Centred (Sheldon) said here
http://cs.trains.com/mrr/f/88/p/198467/2167676.aspx#2167676
"The hitches do not require any chains or other binders - that was the whole point of their invention." See the link for soke other good info.
Trailer Train history
http://www.model160.com/n-scale-news-blog/intermodal-flat-cars-the-85-pioneers/
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
I am currently modeling Seaboard Air Line early-mid 1960s and am looking for specifications on how trailers were secured to flatcars. I have many pictures but actual specifications, if they exist, i don't have. Any help would be appreciated.