Here’s something a bit different: a semi-trailer coach/bus that’s driven from the trailer. There were sound reasons for this, as it lowered overall height and weight, increased maneuverability, lowered the floor for easier entry and a lower center of gravity, and a few others, according to its designer and patent holder, George W. Yost. Built be Heisers, Inc., and called the Tri-Coach, a number were made and used in the Seattle area.
Here’s the patent drawings that show how it worked:
It appears that the steering column and gear shift went right through the center of the fifth wheel, which of course is the obvious solution.
As usual, that splendid repository of history, coachbuilt.com, has a long and detailed write up on Tri_coach. here’s the section relevant to this semi-trailer coach:
Constructed by Heisers, Inc., the original ‘Tri-Coach’ utilized a 98″ short-wheelbase 1 1-2-ton 4-cylinder Ford cowl and chassis, with the ‘fifth wheel’ suspension mounted about 18 inches forward of the power axle. The driver’s seat was inside of the passenger coach. The Tri-coach prototype was featured in a 1932 Standard Oil Bulletin:
“A Bus Conceived in Seattle
“Now in the service of the Suburban Transportation System, which operates busses between Edmonds, Richmond Beach, Lake Forest Park, Des Moines, Lake Burien, and Seattle, is a new type of motor-coach developed by that company, whose manager, George W. Yost, conceived it. As the accompanying illustrations show, it is of the truck-and-trailer type. Because of its comparatively light weight (7700 pounds), a four-cylinder Ford motor serves to give it ample speed and power.
“The truck is a standard Ford truck having a shortened wheel-base, its rear axle equipped with double wheels. Upon it is mounted a fifth-wheel, which supports the forward end of the passenger body, or trailer, in turn support toward the rear by a wide trailer axle that is equipped with brakes and dual rear wheels.
“Of the numerous advantages claimed for this motor-vehicle, our correspondent notes the following: its design permits a reduction in height; the elimination of all machinery from under the passenger section makes it possible to have a bus but one step off the ground, the low center of gravity thereby- achieved resulting in easier riding and reduced side-sway, as compared with busses having greater clearance. Also, it is asserted, there is an elimination of body twists, which is accomplished by the three-point suspension. This bus can complete a turn in a fifty-foot circle. The coach body, which is steam-heated, is of steel and aluminum, constructed by Heisers, Inc., of Seattle. Castings for the fifth wheel were manufactured by the Western Gear Works, also of Seattle, and the truck chassis was adapted to this special use by the Yost Auto Company, local Ford dealers. The weight and cost of this Seattle creation are asserted to be about half that of other busses of equal carrying capacity. It was planned and built with the idea of producing a bus that will render satisfactory service with a reduction of cost in operation. If, after an extended try-out in actual service, it meets the expectations of the designer and operators, others like it may replace those that constitute the present fleet of the Suburban Transportation System.
“It is operated exclusively on Standard Oil products, and its ten wheels, not including the fifth, appear to be a sweet potential market for Atlas tires.”
The Tri-coach was not the first trailer-bus of its type, back in 1929 aviator Glenn H. Curtiss had designed and constructed a series of nearly identical 5th wheel trailer buses that were put into service by the Transportation Co., Dallas, Texas and the Miami Beach Transportation Co. in Miami, Florida. In 1934 the Highland Body Co. of Cincinatti, Ohio offered their own take on the semi-trailer bus called the ‘Highland Acticulated Coach’ using equipment supplied by Trailmobile.
Yost’s Ford semi-trailer coach was also featured in the ‘What’s New In The Bus Market’ section of the February 1933 issue of Bus Transportation:
“Look! A Semi Trailer Coach
“Powered by a Standard four-cylinder Ford Truck which was shortened to a 98” wheelbase, a semi-trailer bus is being operated experimentally in service on the lines of the Suburban Transportation System, Seattle, Wash., George W. Yost, general manager of this organization is the inventor of this new type of coach and the body firm, Heisers, Inc., are the creators of this special all-metal body. The semi-trailer seats 26 passengers with full standing headroom for 20 more.”
In 1934 an improved Tri-Coach powered by a flathead Ford V-8 was put into operation. The bus was featured on a circa 1934-35 Ford postcard advertising it as a V-8 Semi-Trailer Coach. The back of the postcard stated it had seating for twenty-six with room for twenty standees:
“A wide choice of Body Types and Equipment adopt the Ford to ANY use… Ford V-8 costs 4 1/4 cents a mile… average fleet cost 9 1/4 cents a mile.”
Yost’s semi-trailer coach proved so successful that by the end of the year the Suburban Transportation System elected to replace its conventional motor coaches with Tri-Coaches, acquiring 3 more in 1935, 3 more in 1936, and 4 more in 1937.
It’s possible that Portland, Oregon’s Wentworth & Irwin may have constructed a few examples under license based on surviving pictures, one of which depicts a Tri-coach in service of the Vancouver-based British Columbia Electric Railway and another that shows a Suburban Transportation System unit with a Wentwin logo in the corner of the photo.
Due to pressure from larger motor coach manufacturers the Washington State Legislature passed a new traffic code in 1937 which made it illegal to carry passengers for hire in a trailer in the State.
Suburban Transportation System fought the new legislation, claiming its Tri-Coaches were not ‘trailer buses’, however they agreed not to build any more Tri-Coaches and the 12 coaches currently in service were ‘grandfathered in’ and remained in use into the early 1940s.
Yost went on to be very active with the firm Newell, which built trolley and buses of all sorts.
Coachbuilt.com also has pictures of two other variants of these Tri-Coaches.
A similar approach was used on a larger scale by the firm Dyson in Australia. Jim Brophy’s post on those remarkable coaches is here. Coincidentally, these were powered by two Ford flathead V8s.
Brakes, clutch, shifter, steering, throttle, spark,, electrical…
that must’ve been one busy center point!
^^^^^I took me a while to fully appreciate everything going on at that center point (as compared to today’s fifth wheel)—-a cool piece of engineering!
That centerpoint would be easier in modern times. Drive by wire. Actually the same thing could have been done in the ’30s with relays and vacuum.
Interesting that the first version used a four. Ford still considered fours to be the default in ’33. By ’35 they realized that nobody bought a Ford to get a four, so they went to all V8. Oddly they brought back fours in pickups in 1940-46 to “replace” the V8-60, but again nobody wanted them.
Due to pressure from larger motor coach manufacturers the Washington State Legislature passed a new traffic code in 1937 which made it illegal to carry passengers for hire in a trailer in the State.
That’s a shame. It’s not as if the driver was oblivious to what was going on in the trailer as he was there too, unlike Dezi Arnaz in ‘The Long Long Trailer’.
Political campaign contributions strike again.
I wonder how accurate that is?
Because, first, actually it’d seem this is an articulated vehicle, rather than a drawn trailer or sem-trailer.
Second, the ’37 date is close to when ICC began heavy regulation of bus business, not sure how well a single intrastate law could bump heads with that?
How accurate beyond newspaper reports do you want it to be?
Looks like a semi trailer to me, and apparently to the Washington Legislature.
These were used locally, not in interstate commerce, so even if the ICC had created regulations it wouldn’t supersede a state law.
You’re just being a doubting Thomas. It’s easy to say “I doubt this happened”, How about proving otherwise with facts, like the original source did at coachbilt.com?
How accurate?
Citation of Vehicle Code, same as the judge can’t be swayed without. lol
I didn’t realize that specific WA vehicle code was cited.
I will look at Coachbuilt for that.
I happen to be familiar with the typical official definition of “trailer” and the pictured articulated bus does not meet that.
If we KNOW that WA law specifically forbade these buses because they were in fact “trailer” by WA definition, I apologize.
Otherwise, newspaper reports… yawn.
When I get a chance I’ll do the homework and report back either way. Then we’ll know.
It’s okay to skip to the last few paragraphs for the punch line.
First, I’ll confess that I only skim read this feature and did not visit the original source article. My ears were perked by a quote in Roader’s comment:
“Due to pressure from larger motor coach manufacturers the Washington State Legislature passed a new traffic code in 1937 which made it illegal to carry passengers for hire in a trailer in the State.”
I wondered how accurate that was. Just a casual doubt because it didn’t smell right.
My wondering perked Paul’s ears and I was chastised for questioning the accuracy of that with no more than intuition and gut feeling.
The premise was that with impropriety “larger motor coach manufacturers” (LMCM) and lawmakers (allegedly) unfairly conspired to make Tri-Coach’s breakthrough design illegal. To me that rang of classic conspiracy theory.
First off, I wondered if LMCM were hoping to control the bus market by stymieing innovation, if they wouldn’t have much larger fish to fry than just Tri-Coach in WA State?
Relevant to that I wondered why if LMCM was hoping for a competitive choke-hold why they’d waste resources with the pipsqueak WA operations, when just over the border would be another fight?
That lead me to whimsically wonder how LMCM became such if they didn’t respect a fundamental axiom of business, namely that: You can’t get ahead while trying to hold others back.
On that same note, I wondered why if LMCM felt that Tri-Coach held such a threatening competitive edge, why didn’t they simply pony-up to buy or license the design? After all, that was typical with most transportation breakthroughs.
The article indicates that apparently Tri-Coach wasn’t averse to licensing. Makes one wonder why nameless LMCM would (allegedly) engage in dirty politics when a simple business deal would procure a supposed far superior product?
Trying to sum it all up realistically, I wondered if more simply it was just that when compared to other designs, the Tri-Coach model of basing a large articulated coach on a light underpowered cheap chassis, a chassis which also “stole” precious length just wasn’t practical. Not practical and added complexity that just didn’t make sense in revenue bus service? To me that seemed more logical.
Trying to give the conspiracy angle a last chance, I wondered why if the articulated bus was such a breakthrough, then why in areas where the design wasn’t “legislated out of business” it didn’t take over?
In a final summary of my wondering, I wondered if the mentioned new legislation wasn’t simply coincidental and actually more concerned with some other trailer-type of passenger conveyance? After all, this was at the dawn of both RV trailer travel and heavy regulation of transportation throughout the United States.
Thus with Paul’s smack upside the head for my constant wondering and questioning I was prodded into finding the underlying 1937 law. I learned, surprisingly, that Washington’s first group of concise and orderly traffic laws were enacted very late, April 1, 1937, in one huge batch. As far as I could determine, there were not any seperate bus-specific rules enacted at the time.
So with renewed wonder I read the relevant definitions and rules.
What master wordsmiths the legislators were! So precise and specific.
As I had originally speculated, plainly, by WA’s own 1937 legal definition, a Tri-Coach “auto-stage” would not be construed as a semi-trailer.
Apparently legal minds reached the same conclusion and Tri-Coaches were allowed to continue in operation.
Simple matters of amending either the “semi-trailer” law (ch 188, sec 113) and/or definitions of “bus” (Auto-stage, Sec 1. d ) to more specifically allow/prohibit the Tri-Coach design were not pursued.
With that I concluded that had lawmakers actually been focused on sinking Tri-Coach then just a bit more of their usual specificity could have torpedoed Tri-Coach once and for all. Again, that was not done.
The record shows that the boys at Tricoach had a lot of fight in them and they weren’t hesitant to put on the gloves for lengthy knock-down drag-out legal battles. In one case with a few thousand dollars in dispute they brawled with no less than the US Government for some10 years! Another extended battle was waged with a competitor over a bit of mandated routing.
With Tri-Coach’s obviously aggressive and well-funded legal strategies frequently going to appellate levels, it seems safe to conclude thatTricoach probably wouldn’t have stopped short of the Supreme Court if they thought they were being jammed by LMCM. I haven’t seen the newspaper article which Paul refers to but the record doesn’t seem to indicate that such a fight took place.
During my research I took a short Google correspondence course lol on the tremendous effort made in the ’30s to codify somewhat uniform vehicle laws throughout the U.S. Since so many States jumped on board simultaneously I have to wonder (don’t we love my wonderings?) if an FDR money grab was linked to States enacting laws based on the Uniform Vehicle Code? By 1945 only six States did not have laws based on UVC.
At the link is a short official blurb on Washington State’s undertaking of building their State’s1937 vehicle code. There is much more detail available on the nuts and bolts of “building” The Code.
Getting serious about traffic laws: DOL History File, 1937
https://licensingexpress.wordpress.com/2010/03/19/getting-serious-about-traffic-laws-dol-history-file-1937-2/
Washington’s essentially “wholesale” enactment of an entire new Vehicle Code included much verbage very similar to the Uniform Vehicle Code and other States’ Codes. The WA Code contained no clear specific wording to make the Tri-Coach design unlawful.
So, the likelihood of impropriety being used to stab Tri-Coach seems extremely remote. If there was any such intent to ban the Tri-Coach design, it clearly was bungled for lack of including just a tiny bit of specific wording in the new Code.
With that I toss this monkey back where it belongs and place the burden of proof on those who alleged that there were underhanded dealings aimed to torpedo Tri-Coach’s articulated bus.
Originally I was simply questioning the accuracy of reports of wrongdoing, now more specifically I highly doubt them.
@ Jim Dandy :
“Not knowing how near the truth is, people seek it far away – how strange “.
-Nate
This certainly shows some “outside the box” thinking. In Mumbai in the 70s there were double deckers that were semis, but with a normal cab. I don’t know if they are still in use.
The engineering is brilliant but the coach is terribly underpowered. No one could have been in a rush to get from Point A to Point B. The Australian version is impressive. With two Ford V8;s it had a chance of moving a little better. It also has a good streamline design. Of course, being critical is not fair on my part. The bus industry for intercity runs was barely getting off the ground. Much was tried. If you have never been behind a GM Coach going up a hill powered by a 4-71 Detroit Diesel, well, you have missed out (sarcasm!). It would huff and puff but the only thing it blew was smoke in your face as you drove behind it. Thanks for a great essay. I always enjoy these adventures into travel. Bring back Claudette Colbert!
It wasn’t “terribly underpowered”, for its times. Yes, from today’s viewpoint, it would seem so. But in 1932, the Ford V8 was commonly used in trucks and buses of all sorts. That power level was highly competitive for a relatively light-medium weight bus or truck at the time,
All traffic was slower then, and trucks and buses a bit more so. 30-40 mph was fast for truck in the early 30s. they used to run in the teens not many years earlier.
Great post – never knew of this one. Coachbuilt.com is a superb site with a wealth of history.
Such a cool looking bus .
-Nate