24 Minutes

1-With the entire train still coupled to the loco at the depot pull past the east switch.

2-Back into the wye and uncouple the observation car.

3-Pull the remainder of the train onto the east track.

4-Back the remainder of the train west past the west switch.

5-Pull into the wye and couple the observation car to the front of the loco.

6-Back the entire train with observation car onto the west track.

7-Pull forward and drop A,B&C between the switches.

8-Shove the observation car east till the loco clears the east switch, then uncouple.

9-Back the loco into the wye.

10-Pull the loco onto the west track.

11-Back up coupling to the A,B&C cars and couple to the observation car.(one move per rules)

12-Pull up to the depot.

12 stops = 24 minutes.  Can you do it in less?

Dave

starting conditions

Very nice solution, except the starting condition has the engine on the east leg of the wye, so I think you need to add two moves at the start. 

We'll see if any of my students come up with 14 moves or less!

Jeff Allen

Proper Prior Planning......

Jeff,

Guess they should have thought about waiting to fuel at step 9 above.  Would leave more time for the game.

I like the ability you have to teach outside the traditional box using real life situations and relating them to railroads.

Dave

student work

I gave the students the problem on Thursday, they took a look and asked questions Friday, and their solutions were due today. These are twelve-year-olds whose experience with trains is remembering the good times they had with Brio (rather useful experience, actually). 

Volunteers projected their solutions (samples below) and described what they did using the vocabulary they had. It was simply awesome. Not only did the presenters provide a high level of descriptive precision but the audience listened with rapt attention (since they also knew the ins and outs of the problem). Students provided incisive critique, alertly identifying instances when the presenter made errors in move counts (which was often). 

A remarkable number of students, like Dave above, started counting from the position of the train at arrival. Perhaps the problem needs to be rewritten that way, it does seem more logical, though it would also make sense to require a refueling stop.

I didn't specify a particular notation strategy and students created methods that seemed reasonable to them. Consequently, you may have some difficulty following their logic, but I thought folks might enjoy seeing the evidence of thinking that went into them. Enjoy:

Turning the train

Where were you when I was in middle school?

More puzzles

The Wylam problem was such a hit with the students that I put together another based on one of Bob Hayden's pieces for Model Railroader back in the 80s. I handed it out at the beginning of the week and students presented their solutions during class on Friday. 

Most of the students were getting the hang of these problems but a few were still confused, mostly by trying to decipher some of the railroad jargon in the text. Having several days to work on it gave them a chance to ask questions and gave me a chance to explain some of the basics of railroading. Students examined the track switches on the Inglenook layout set up in my room and were excited to discover how the configuration of the frog and the mechanism of the points worked to allow flanged wheels to take alternative routes.

One of the students rides horses on weekends and commented that the "frog" looked like the part of a horse's hoof called a frog, and with a little research we discovered that's not a coincidence. Now I was the student!

Here's another one from Bob Hayden, simplified somewhat to make drawing solutions a bit easier, that I plan to give the students this week. It's really the most straightforward of the three, my deliberate attempt to put it within reach of every student. 

This week I also plan to bring the "big layout" sections down from Summer storage upstairs and begin reassembling them so we can pick up where we left off last year.  Should be fun. 

Jeff Allen

one thing

One thing I have a problem with is the word "Fireperson".......the correct term or word if Fireman........lets be real here and not politically correct.

Just one?

In the case of my students, Fireperson is correct (and to them it doesn't sound the slightest bit contrived!).

Why did "brakeperson" escape mention?

Jeff Allen

Summit Moves

By my count, you would need 14 moves to complete the task leaving 1 minute to spare.

Unless you count the final 2 moves to re-build the train as 1 move (13 total) and in that case you would have 4 minutes to spare.

How'd I do?

Cheers,

Dave

I'm perplexed

I think we'll need to review the moves Dave! I could be wrong, but I think the twelfth and thirteenth moves reassemble the train in the clear.

Bob Hayden's original solution (below) also counted 14 moves, but he joined the two cuts before running around, which left his engine fouling the main when he backed onto the train so he needed the fourteenth move to get into the clear. I'm pretty sure eliminating his move 10 saves a move and clears the engine when backing to the final join. Your note suggests you also left the two cuts to be joined by the final move, so I'm not sure where the extra move is.

It is VERY likely that I'm in error, that's generally the safest default assumption. But we'll have to post our solutions to be sure. I'm going to wait until my students turn in their solutions this Friday in case someone has a brainstorm!

Jeff Allen

Moves

1. Break the train between cars 3 and 4 and run forward to clear the spur switch.

2. Drop the three cars and continue forward light until the West switch is cleared.

3. Throw the West switch and run around the train until the East switch is cleared.

4. Throw the East switch and couple onto the rest of the train.

5. Shove the train into the spur after the switch has been thrown to pick the two empties.

6. Back the train out of the spur until the switch is cleared and re-align the switch with the siding.

7. Shove the train forward on the siding until the empties clear the switch and couple up with the 3 cars left on the siding between the spur switch and the West switch. Leave the 5 cars there (this should leave room for one more car and prevent the main from being fouled).

8. Back the train up past the spur switch and align the switch to the spur.

9. Shove the train into the spur and drop the loaded car.

10. Back the train out of the spur. Align the switch back to the siding and drop the rest of the train between the spur and the East switch.

11. Run light out of the siding and clear the East switch.

12. Re-align the East switch and run around the train until the West switch is cleared.

13. Throw the West switch and join both cuts of cars.

14. Re-align the West switch with the main.

In my original count, I didn't have the separate step to re-align the West switch at the end of the sequence as I assumed that the person who through the switch to align the switch with the siding in step 13 would remain on the ground to re-align the switch with the main after the engine had passed due to the engine running light.

It might be possible that my step 2 is not required. I would have to think that 13 or 14 moves would be correct. Depends on how good your railroad employees are.

Cheers,

Dave