Bus Scheduling using interlining

[nostalgia]

Based on comments, Here are some examples where I think interlining would be helpful.

 

There is no need to deadhead from the depot to Westbury to begin a N35 run and deadhead a bus from Westbury after the operator's last N35 run. Operators can change at Roosevelt Field (RF). N22 operators can also change at RF so that two buses don't don't have to deadhead between the depot and Hicksville.

 

A N79 operator can take a bus from RF to begin work at Hicksville. The relieved N79 operator can take a bus to RF.

[nostalgia]

I continued my sleuthing to uncover interlining. While long layovers in timetables suggest interlining, it's NOT always the case. You have to go to terminals to see what's happening.

 

Hempstead Transit Center June 9

 

A N32 dropped off passengers in the N6 Bay and later left as a N6. I saw a bus arrive and depart as a N6. The N6 headway is 12 minutes and the N31/32 headway is 20 minutes so there aren't enough N31/32s to interline with all the N6s.

 

The 70 series stays on the line. N71 interlined with N72 but it's the 70 series.

 

Roosevelt Field June 16

It was a little difficult to catch everything. Some buses changed the destination sign to "NOT IN SERVICE" before pulling into a bay. Some buses don't pull into a bay to discharge. This is an operator's shack next to the first bus bay where some buses discharge and park during their layover. However, I was able to find:

 

N16 has a 40 minute running time from Rocville Centre. The bus arrives at :45 and leaves at :15. This schedule is a prime candidate for interlining. Surprisingly, there is NO interlining. One bus pulled into the parking lot to wait for the "advertised" and a second one parked adjacent to the last bus bay and discharged passengers. They both left as N16.

 

However, consistently, the N43 and N15 interline. At first, it looks unnecessary from the timetables. The N15 arrives at :09, :29, and :49 and leaves at :00, :20, and :40. running time is 70 minutes so recovery time would be 7 minutes. There is 11 minutes between scheduled arrival and departure so it looks like interlining is not necessary.

 

The N43 arrives at :06 and :36 and leaves at :15 and :45. Running time is 40 minutes so recovery time would be 4 minutes and there is 9 minutes scheduled between arrival and departure.

 

Because the two interline, the N15 that arrives at :29 leaves on the N43 at :45, a layover of 16 minutes. The N43 that arrives at :36 leaves on the N15 at :00. N15 needs more recovery time than the N43 so this is how to increase it without affecting the 20 minute headway.

 

The problem is there are 3 N15s a hour but only 2 N43s a hour so I don't know what happens to the third N15. It would have an unusally long layover for the next N43. It may go back on N15.

 

Mineola (I don't remember)

An arriving N40 leaves as N41 and an arriving N41 leaves as a N40.

 

Freeport June 16

I'm not sure there's a regular pattern. Arriving N4s from Jamaica left as a N4 and N40. An arriving N36 left as N41. An arriving N40 left as N43. I was there for about two hours and I see more time would be required to understand the situation.

 

Unrelated to interlining

There was a lot of business on the N88. Even between 6 and 7 PM, a lot of passengers travelled to the beach. There are spare buses waiting to be put into service with direction given from a street supervisor.

 

Hope this is helpful.

[checkmatechamp13]

When they want the layover to be 10% of the runtime, do they mean one-way or round-trip? I guess they mean round-trip, but split between the 2 terminals, right? (So the N15 requires at least 14 minutes of layover total, so theoretically it could be 11 at one end and 3 at the other end).

 

I wonder what the logic behind having the buses sit there must be. Unless those are runs given to people who have "connections" within the agency or something.

[nostalgia]

When they want the layover to be 10% of the runtime, do they mean one-way or round-trip? I guess they mean round-trip, but split between the 2 terminals, right? (So the N15 requires at least 14 minutes of layover total, so theoretically it could be 11 at one end and 3 at the other end).

 

I wonder what the logic behind having the buses sit there must be. Unless those are runs given to people who have "connections" within the agency or something.

 

 

The purpose of recovery time is to give the operator sufficient time to get to the end of the line and leave on time for the next trip. Therefore, I'd think that the recovery time is based on a one way trip.

 

The long N16 layover occurs because it doesn't interline with anything at the Field. If the planning department wants hourly service, and the running time is 40 minutes, the bus will just sit. Unless the N16 interlines with something at Rockville Centre, the schedule can be adjusted so that the layover is the same at both ends. Currently, the layover is 10 minutes at RC and 30 minutes at the Field.