AARoads Forum

Regional Boards => Mid-South => Topic started by: US71 on October 22, 2018, 10:06:29 PM

Title: Leading Yellow Error
Post by: US71 on October 22, 2018, 10:06:29 PM
Fort Smith recently completed a major road project, straightening/widening Jenny Lind Rd and extending Ingersoll Dr to Business 71 at McKinley St.
Part of this project included new signals at Jenny Lind and Cavanaugh,  Jenny Lind at Ingersol, and Jenny Lind at Zero St/Bus 71, plus a new signal at Ingersol and Bus 71.

I suspect the signal at Jenny Lind and Zero has been mis-programmed.  Northbound traffic on Jenny Lind has protected right and protected left. When cross traffic on Bus 71 gets yellow, the right turn yellow momentarily turns on just before the left turn green activates. Now, I'm no traffic engineer, but the "leading" yellow doesn't seem right.  Is this a standard I'm not aware of or a mis-wired controller (not the first time) ?
Title: Re: Leading Yellow Error
Post by: Revive 755 on October 22, 2018, 10:42:41 PM
I'm not an expert in signal cabinets, but I'm leaning towards either miswiring, a short, or some controller malfunction.  Ideally the signal would have been tested before being put into operation.  The conflict monitor/malfuncton management unit ought to be switching the signal over to a failure mode (usually an all red flash) when this happens.

The MUTCD only appears to allow going from a steady yellow going to a steady green when the signal is transition into preemption mode for an emergency vehicle, railroad crossing activation, or drawbridge (4D.27 Paragraph 08).
Title: Re: Leading Yellow Error
Post by: jakeroot on October 23, 2018, 12:06:13 AM
Is the right turn signal an all-arrow setup?
Title: Re: Leading Yellow Error
Post by: US71 on October 23, 2018, 08:33:06 AM
Quote from: jakeroot on October 23, 2018, 12:06:13 AM
Is the right turn signal an all-arrow setup?

No, it's a 5-light signal
Title: Re: Leading Yellow Error
Post by: jakeroot on October 23, 2018, 02:19:23 PM
Quote from: US71 on October 23, 2018, 08:33:06 AM
Quote from: jakeroot on October 23, 2018, 12:06:13 AM
Is the right turn signal an all-arrow setup?

No, it's a 5-light signal

Thanks.

I've seen lights where the arrows briefly activate at the end of a cycle, but this obviously isn't the case since it would be for the wrong movement. So this sounds like an error.

If you have the chance, definitely grab a video.