Seat numbers; why ACDF instead of ABCD?

[Mailliw]

Why do Amtrak seat numbers go A-C-D-F instead of A-B-C-D?

 

[VentureForth]

Not 100% sure, but back when Americans were skinnier, I think seats were 3x3 or 3x2. Japan's bullet trains are 3x2 in economy. So, I think that B & E seats were the imaginary 'aisle' seats.

Just my 2¢ worth of guessing.

 

[Ryan]

While there is a ton of variability, convention is that the "missing" B and E seats would be middle seats.

 

[ehbowen]

Consider also the era when ARROW was programmed initially; 90%+ of airline flights were either 5-abreast (DC9) or 6 abreast, with B & E universally being middle seats. Going from memory on this, but I believe that the 5-abreast DC-9 also skipped one of the middle seat letters...ACDEF. So there was precedent...and Amtrak may have been in the, "See, we're just like an airline too!" mode for the benefit of travel agents.

 

[lyke99]

No solid data, but my guess would be to put seat identifiers into "airline language" A's and F's are window seats, C's and D's are aisle seats. Since there are no middle seats, B's and E's are missing.

 

[Mailliw]

Thanks, it didn't occur to me that Amtrak would need to follow airline hooking conventions.

 

[Devil's Advocate]

I agree that the decision was likely some sort of nod to airlines and travel agents but to the best of my knowledge Amtrak never allowed anyone to book a specific seat until recently. Back when green screens were cutting edge technology knowing that A or F was going to be a window seat would have been very useful, but it still did you or your travel agent no benefit on a carrier with undefined bookings like Amtrak.

 

[me_little_me]

Executives don't know the alphabet? Wow!

 

[joelkfla]

I agree that the decision was likely some sort of nod to airlines and travel agents but to the best of my knowledge Amtrak never allowed anyone to book a specific seat until recently. Back when green screens were cutting edge technology knowing that A or F was going to be a window seat would have been very useful, but it still did you or your travel agent no benefit on a carrier with undefined bookings like Amtrak.

But perhaps they were looking ahead to adding seat assignment in the future.

 

[Willbridge]

But perhaps they were looking ahead to adding seat assignment in the future.

That seems plausible as many of the early Amtrak employees had worked for rail companies that offered seat assignments. When I first made a trip from Portland to Chicago in 1967 the NP penciled "sell last" into the car diagram for the seat next to mine so I had room to eat the picnic supper my mother had made for me.

Before that I thought that seat assignments were a tool of the devil because the SP screwed them up so many times. I can't forget the shouting argument across the aisle from me on the Cascade regarding a seat that was triple-booked somehow. Perhaps it's just as well that Amtrak didn't try it.

 

[railiner]

the NP penciled "sell last" into the car diagram

Interesting that you should mention the car diagrams...
When I was selling Amtrak and D&RGW tickets at Denver in the '70's and early '80's,, The Grande was still using the cardboard diagrams, to keep track of each trains sales. Their director of passenger service, Leonard Bernstein would visit us each morning to keep track of sales, and when a car was "sold out", he might or might not give us another car to sell. By the way, even though we penciled in passenger's names for each numbered seat and car, the passenger was not assigned to that particular spot, they could choose any when boarding....
That all ended when Amtrak took over the route in 1983.

Just wanted to add, that The Grande also sold tickets at their headquarter's building a few blocks away, mostly mail order...
Close to departure date, Mr. Bernstein would bring all of those diagrams over to the station to put together with ours...

 

[MARC Rider]

I agree that the decision was likely some sort of nod to airlines and travel agents but to the best of my knowledge Amtrak never allowed anyone to book a specific seat until recently. Back when green screens were cutting edge technology knowing that A or F was going to be a window seat would have been very useful, but it still did you or your travel agent no benefit on a carrier with undefined bookings like Amtrak.

In 1975, I was at the station in Baltimore, buying a ticket to New York. The agent said that there was a seat on the Champion, up from Florida a couple hours late that would get me into New York before the next scheduled unreserved regional train. He sold me a seat on that one (for the same price as the regional train), and I seem to recall that the actual seat was reserved, not just a guarantee of a seat. That was a great ride, by the way. The long-distance Heritage coach seat was one of the roomiest I've ever had on a train, with incredible recline. Much nicer than the coach seats I rode on the Broadway Limited a couple of years earlier. The coach was also half-empty, as I guess a lot of people get off in Washington, and even though they sold local NEC tickets on it, most people weren't going to reserve space on a train that probably ran late all the time.

 

[cirdan]

Just a very long and totally speculative shot here.

But before the days of the internet, automated bookings, where they existed, would have been made by phone lines.

Somewhere on Youtube there is a clip about the PRR booking system which actually used the telephone's dialing function to select a train and then a seat.

Although the touch-dial system typically only codes the digits 1 thru 9 followed by 0 (and also * and #), it actually uses an overlay of two signals each of which has 4 possible frequencies, meaning that 16 different digits are possible. The remaining 6 digits which were rarely used were internally allocated the letters A thru F, possibly in anticipation of the hexadecimal system of computers (this assumes an abolition of the use of the * and # keys).

So it would technically have been possible for a booking clerk to dial the seat number directly on a 16-button telephone. For example 12C.

Because this was still not a digital system, there was a risk of static on the line leading to a bad transmission and the wrong information received. To add robustness to such a system you would if possible avoid using adjacent (and hence similar) frequencies as much as possible.

 

[zephyr17]

Simplest explanation.

Arrow is a one off of an airline system, Sabre.

Airlines use A-F to accommodate 6 across. In 4 across seating, such as narrow body First Class, airlines use A,C,D,F just like Amtrak.

All Amtrak equipment in use was acquired after Arrow's implementation. Seat identification methodology was set up with the reservation system in mind in case they ever wanted to reserve seats.

 

[jis]

Actually even in a 16 button DTMF keypad, there really was no way to encode all 6 letters since two of those codes were taken by "*" and "#". There are 16 button keypads that did allow dialing A, B, C and D though.

Frankly I don't think DTMF encoding has anything to do with seats A-F in a row of seats. The A-F where found probably has more to do with the width of a 707 cabin and almost standard Economy Class seat width since the early days of jet age. with the advent of the 707 and DC-8. that made 6 seats per row in Economy almost a universal standard in those planes. Of course there are Amtrak coaches with other seat numbering schemes to, but this thread is not about them, and they all came later.

The Amtrak seat numbers came because Arrow was derived from an airline reservation system which accommodate A through F, and the general practice even then was to assign A and F to window and C and D to aisle. It is as simple as that. Whoever made the Arrow conversion simplified their task by not fiddling around with thing that they did not need to fiddle around with.

 

[Trogdor]

There’s a lot of interesting speculation in here, but I don’t see anything definitive that actually ties seat numbers to any Arrow programming. In fact, the seat numbering system in question only applies to Amfleets (and maybe only Amfleet 1s? I don’t remember the Am-2 numbering). Horizon cars and Superliners just start at 1 and count up to the number of seats in the car (i.e. 68 or 70-something). Were the Amfleet 1s delivered with that seat numbering system, or was it something added later on in some fleet refresh program?

Airline reservation systems can handle all kinds of seat number/letter combinations (after all, widebody planes can have seat letters going up to K, or maybe even higher depending on the quirks of the carrier involved), and this would have been the case dating back to at least 1970 when the 747 entered service (i.e. before Amtrak was even created).

 

[Trogdor]

Following up on my prior post:

http://cs.trains.com/ctr/b/mileposts/archive/2020/05/28/amfleet-enters-its-own-classic-era.aspx
The third photograph in this link clearly shows the interior of an Amfleet I with numeric seat numbers, similar to the rest of the Amtrak coach fleet. I don’t know when the number-letter system came in for the Amfleets, but my guess would be with the Capstone rehab program of the late 90s/early 2000s.

 

[Trogdor]

In 4 across seating, such as narrow body First Class, airlines use A,C,D,F just like Amtrak.

https://seatguru.com/airlines/Delta_Airlines/Delta_Airlines_Airbus_A320_B_new.php
https://seatguru.com/airlines/American_Airlines/American_Airlines_Boeing_737_Max_8.php
https://seatguru.com/airlines/United_Airlines/United_Airlines_Airbus_A320_V3.php
https://seatguru.com/airlines/JetBlue_Airways/JetBlue_Airways_Embraer_190.php
https://seatguru.com/airlines/United_Airlines/United_Airlines_Embraer_Emb_175.php

All Amtrak equipment in use was acquired after Arrow's implementation. Seat identification methodology was set up with the reservation system in mind in case they ever wanted to reserve seats.

Arrow was implemented in 1981. The Amfleet Is and Superliner Is predate it by several years. Horizons, Superliner IIs, and the various state-owned trainsets, came later.

 

[jis]

So @Trogdor what is your speculation about why it is ACDF? I don’t think anybody is arguing about any of the points you are making. You are mostly shadow boxing with yourself I am afraid

 

[Trogdor]

So @Trogdor what is your speculation about why it is ACDF? I don’t think anybody is arguing about any of the points you are making. You are mostly shadow boxing with yourself I am afraid

Amtrak marketing wanted to compete against airlines on the NEC. Sounds simple.

I don’t think I’m shadowboxing at all, as half this thread is about Arrow limitations, and I see no evidence that this is an actual thing.

 

[Asher]

Why do Amtrak seat numbers go A-C-D-F instead of A-B-C-D?

This just backs up DAs post.
Occasionally, aircraft with a seating structure of 2+2 may letter the seats as "ACDF" to keep with the standard of A/F being window and C/D being aisle on short-haul aircraft (which generally have 3+3 seats).

 

[west point]

Just so you know DTMF 16 button phones came out before the general public got the 3x4. Who used the 16s? It was the DOD that used the right hand column to prioritize calls. That was around 1960 but cannot be sure ?

 

[RebelRider]

Airlines use A-F to accommodate 6 across. In 4 across seating, such as narrow body First Class, airlines use A,C,D,F just like Amtrak.

Delta Airlines uses A, B, C, D for their narrow body First Class seats and most of their widebody aircraft. I believe the A330s are the only ones conforming to A, C, G, J for the forward cabin. Probably a legacy holdover from Northwest Airlines.

 

[EchoSierra]

The Amfleet Is were originally delivered with the seats placarded as such. The Amfleet IIs have placards with straight numeric seat numbering. I don't know if Amtrak specified this, or if Budd simply just did what they did.

 

[railiner]

The Amfleet Is were originally delivered with the seats placarded as such. The Amfleet IIs have placards with straight numeric seat numbering. I don't know if Amtrak specified this, or if Budd simply just did what they did.

The number-letter combination makes it much easier for a boarding passenger to locate their seat, if it is assigned....