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What is a Lunar Signal?

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What is a Lunar Signal?
Posted by zwspnby9 on Tuesday, April 4, 2006 10:58 PM
Like on the BNSF's Gateway Subdivision in Northern California, what is the basics of the "Lunar Signal", and what is "Lunar Signal?"
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Posted by David_Telesha on Wednesday, April 5, 2006 1:28 AM
In some Cab Signals, Lunar White is used to indicate stop or in some, any other indication other than clear.
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Posted by csxengineer98 on Wednesday, April 5, 2006 4:25 AM
signals that have a lunar white light in them for restricting indications... its not a true "white" light... its more like blueisth white...much like the moon in color...thus the name lunar white...
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Posted by edblysard on Wednesday, April 5, 2006 5:30 AM
The aspect of a Lunar signal is a bluish white light...
The indication is proceed at restricted speed.
GCOR rule 9.1.11

Most of the time you find a Lunar at yard entrance or sideings, it is used to control access to a yard from a main line, and vice versa.

Ed

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Posted by Anonymous on Wednesday, April 5, 2006 5:56 AM
I have seen them on the Main line too.
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Posted by JoeKoh on Wednesday, April 5, 2006 6:29 AM
lunars on csx basically mean to stop then proceed after getting clearence from the dispatcher. csx also uses them for when they have trains playing follow the leader on the main.
stay safe
Joe

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Posted by tree68 on Wednesday, April 5, 2006 6:41 AM
It seems like any time I've seen collections of signal indications that the lunar is a separate head on the mast, as opposed to being one of the colors displayed by the main signal head(s). Sort of a "OK, here's your signal, and oh, by the way..."

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Posted by CSSHEGEWISCH on Wednesday, April 5, 2006 7:24 AM
I'll agree with tree68, I've never seen Lunar displayed on a single-head aspect, usually below one or two reds to display a restricting indication. The nearest that I've ever seen to Lunar on a single-head is on a color position light signal, where two lunar lamps are displayed in the lower-quadrant aspect.
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Posted by GN-Rick on Wednesday, April 5, 2006 7:31 AM
On the GN, Lunar White signals were indicative of a spring switch, according
to their edition of the CCOR.
Rick Bolger Great Northern Railway Cascade Division-Lines West
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Posted by Anonymous on Wednesday, April 5, 2006 7:39 AM
QUOTE: Originally posted by CSSHEGEWISCH

I'll agree with tree68, I've never seen Lunar displayed on a single-head aspect, usually below one or two reds to display a restricting indication. The nearest that I've ever seen to Lunar on a single-head is on a color position light signal, where two lunar lamps are displayed in the lower-quadrant aspect.
You mean Dwarf Signals.
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Posted by chad thomas on Wednesday, April 5, 2006 10:20 AM
You are never going to see Lunar on the Gateway sub as there are no signals there. It's dark territory, TWC. There was a few miles on the exWP right out of Keddie that was once CTC, But that was taken out of service decades ago. The UP does use lunar aspects on the Feather River Route though. It will usually be a red over lunar at the entrance to a yard indicateing restricted speed.

Actually there are a couple signals on the Gateway sub. The distant and home signals at the automatic interlocking with the Modoc Northern line in Stronghold.
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Posted by CSSHEGEWISCH on Wednesday, April 5, 2006 10:28 AM
QUOTE: Originally posted by BNSFrailfan

QUOTE: Originally posted by CSSHEGEWISCH

I'll agree with tree68, I've never seen Lunar displayed on a single-head aspect, usually below one or two reds to display a restricting indication. The nearest that I've ever seen to Lunar on a single-head is on a color position light signal, where two lunar lamps are displayed in the lower-quadrant aspect.
You mean Dwarf Signals.

Not necessarily, although some of the dwarf signals at Chicago Union Station are color position light signals. B&O, Alton (which was owned at one time by B&O), and a handful of other roads used color position light signals as regular trackside block and interlocking signals.
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Posted by tree68 on Wednesday, April 5, 2006 10:37 AM
QUOTE: Originally posted by BNSFrailfan

QUOTE: Originally posted by CSSHEGEWISCH

I'll agree with tree68, I've never seen Lunar displayed on a single-head aspect, usually below one or two reds to display a restricting indication. The nearest that I've ever seen to Lunar on a single-head is on a color position light signal, where two lunar lamps are displayed in the lower-quadrant aspect.
You mean Dwarf Signals.

No - on a signal mast.

|o - Regular signal head
|o - Maybe another regular signal head
|
|o - Lunar
|
|

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Posted by Chris30 on Wednesday, April 5, 2006 10:58 AM
I've seen the lunar signal used on the UP Geneva Sub at the Park Interlocker in Elmhurst, IL many times. The Park interlocker is the entrance/exit from Proviso Yard. The only time I've seen the lunar signal is for eastbound trains on track #1 going 1 to 1 (diverging (3 main tracks to 2 main tracks)) through the plant. I don't believe (but I'm not 100% sure) that the lunar signal indicates to proceed at a restricted speed past the signal. I've never seen a train proceed past the lunar signal. The lunar signal appears immediately after the first train passes and seems to be more of a signal that the dispatcher has stacked or fleeted the signal. This is the usual signal pattern that I see when one east bound train goes 1-1 at Park and then a lunar signal appears for the next eastbound(s) going 1-1 at Park also:

train #1.................................train #2
-------------------............----------------------------------
.red .......red................red.........red..........red
...|............|...................|.............|..............|
green ....red................red.......yellow......green
...|............|...................|.............|..............|
.red........red..............lunar........red...........red

After train #1 passes the green diverging signal on the signal bridge, the signals for track #1 east will be red on all three lamps for @2 seconds before the lunar signal appears for the next eastbound. Once eastbound #1 is a certain distance from the Park Interlocker, train #2 east gets a diverging approach signal 1-1 at Park and the lunar signal on the bottom most lamp returns back to red. Finally, eastbound #2 gets a diverging clear signal.

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Posted by CSX FAN on Wednesday, April 5, 2006 10:58 AM
Didn't the B&O use them on top of there position signals? The one top center or offset to the left.

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Posted by Rodney Beck on Wednesday, April 5, 2006 12:35 PM
On BNSF a lunar signal is restricting which means proceed at restricted speed not exceeding 20mph, we engineers most often go about 10 mph because we must be able to stop within half the range of vision.

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Posted by michaelstevens on Wednesday, April 5, 2006 12:49 PM
Yet another application or interpretation of "lunar signal" are the bluish white signal lamps on top of a grade crossing gate and signal mast. These lamps are oriented towards an oncoming train and they flash in synchrony with the grade crossing warning lights, to confirm (to the oncoming train's Engineer) that the gate arms are down and that the warning lights are working.
At least that was their description (by Bombardier, NJ Transit and Conrail Shared Assets) during the recent construction, testing and commissioning of the River Line, between Camden and Trenton NJ.
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Posted by kenneo on Wednesday, April 5, 2006 2:17 PM
Lunar signals indicate something special. At a yard entrance, for example, it used to be that the Yardmaster would telephone the herder to go out and line a train into the yard into track so-an-so. The herder would do this and then give a "come-ahead" signal to the engineer of the desired train.

In technical teminology, this is a "come-on" signal. They can be a color light, a hand signal, a letter-indicator light, a Lunar, or some other appropriate device or person. Generally, now, when a Lunar is displayed, the crew will look into the special instructions under Rule 9.1.nn and under the station name where they are located, follow the instructions for "LUNAR". This could be a switch indicator, a call-on, or anything else the railroad wants to use it for at that location and on that mast. This can include an implied or explicit "Flashing Red" depending on the need at that location.

Again, technically, a Flashing Red is "Proceed at Restricted Speed without stopping (that is, without stopping at the signal)". The location of the head on the mast will determine which route this signal is displayed for.

I will use a specific example here ---- at one interlocking that I worked, it included a junction, several corssovers, a switching lead, two main lines, a diverging main and two yard entrances. Some switches were controlled by me, some by a herder, and all of the signals were controlled by me. So when the herder had completed the lining of his switches as instructed, he would inform me and I would light the call-on - a RED over LUNAR.
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Posted by PBenham on Wednesday, April 5, 2006 4:18 PM
I have seen lunar white lights used as hotbox warning indications about two miles past a hotbox detector (servo type) on the former Erie, in signaled territory. I have also seen them in use to indicate spring switches facing that were out of their "normal"(as opposed to reverse) position. If a spring switch had to be spiked in reverse the lunar would be lit to warn oncoming crews of the reverse main running ahead. I can't recall the rule that covered this circumstance,Nickel Plate (and N&W for about 35 years on ex-NKP after the 1964 merger)used this practice.
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Posted by csxengineer98 on Thursday, April 6, 2006 1:55 AM
QUOTE: Originally posted by JoeKoh

lunars on csx basically mean to stop then proceed after getting clearence from the dispatcher. csx also uses them for when they have trains playing follow the leader on the main.
stay safe
Joe
no...not true...on csx...unless your running on norc bleneded rules... it means proseed at resticted speed... the signal is your promtion...(at interlockings and what not) or as you did state that is true... to follow behind a train if the track block is occupied head....
csx engineer
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Posted by zwspnby9 on Thursday, April 6, 2006 2:03 AM
QUOTE: Originally posted by chad thomas

You are never going to see Lunar on the Gateway sub as there are no signals there. It's dark territory, TWC. There was a few miles on the exWP right out of Keddie that was once CTC, But that was taken out of service decades ago. The UP does use lunar aspects on the Feather River Route though. It will usually be a red over lunar at the entrance to a yard indicateing restricted speed.

Actually there are a couple signals on the Gateway sub. The distant and home signals at the automatic interlocking with the Modoc Northern line in Stronghold.


I actually got a program titled "Runnin the Highline" BNSF's Gateway Sub from PENTREX. While departing NORTH or EAST the crew change point at Quarry road north of Keddie on BNSF track the Engineer said that they had a steady Lunar signal? But as I understand, ITS DARK TERRITORY. So how did he know that he had a steady Lunar signal? Beats me?
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Posted by kenneo on Thursday, April 6, 2006 5:00 AM
Signals exist in dark territory. For instance, the automatic interlocking at Stronghold has four (4) signals - two in each direction - one distant and one home.

At Keddie, CTC exists up the Inside Gateway (this is what the whole route from Keddie to Wishram is called) for a short distance, and that Lunar signal most probably was the "call on" to indicate the train had permission to enter dark territory. A green, for instance, could not be used because there would not be another signal byond this particular signal. The Special Instructions may also authorize a "flashing Lunar" and then describe what actions the crew is required to accomplish.
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Posted by mbkcs on Thursday, April 6, 2006 5:12 AM
QUOTE: Originally posted by kenneo

Lunar signals indicate something special. At a yard entrance, for example, it used to be that the Yardmaster would telephone the herder to go out and line a train into the yard into track so-an-so. The herder would do this and then give a "come-ahead" signal to the engineer of the desired train.


I remember lunar signals from dispatch class. But I have never heard the term "herder" except in relation to sheep or cow-punching. Was this an official RR term or the slang of railfans? And didn't the conductor line the train into the yard after receiving authority to enter? Can you help me understand this, please?

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Posted by kenneo on Thursday, April 6, 2006 8:05 AM
A herder is a switchman whose assigned duties are to line switches - usually at yard entrances - from the main line into the yard tracks for arriving or departing trains and that authority extends for one mile byond the farthest gate (switch). The signals remain in the dispatchers or interlocking operators control.
Eric
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Posted by chad thomas on Thursday, April 6, 2006 12:29 PM
QUOTE: Originally posted by kenneo

Signals exist in dark territory. For instance, the automatic interlocking at Stronghold has four (4) signals - two in each direction - one distant and one home.

At Keddie, CTC exists up the Inside Gateway (this is what the whole route from Keddie to Wishram is called) for a short distance, and that Lunar signal most probably was the "call on" to indicate the train had permission to enter dark territory. A green, for instance, could not be used because there would not be another signal byond this particular signal. The Special Instructions may also authorize a "flashing Lunar" and then describe what actions the crew is required to accomplish.


CTC used to go up to Clear Creek Jct. (and mabee a little beyond) some 35-40 miles north of Keddie but it was taken out of service around the time of the UP merger. If there is any CTC north of Keddie the distance would probably be better measured in feet then miles.

BTW- The northern Cal railfans I Know consider the line between Chemault and Wishram to be the Oregon Trunk and the section between K Falls and Keddie to be the Inside Gateway even though the OT is part of the Inside Gateway route.

The distant and home signals on the BN tracks in Stronghold were semaphores till a few years ago. These are what they have there now.
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Posted by kenneo on Thursday, April 6, 2006 6:41 PM
Chad ------

Oregon Trunk === Wishram to Bend. Joint operation with the UP and BNSF. All BNSF ownership except for a streach of track between South Jct and Metolius which is owned by the UP.

Great Northern == Bend to Chemult; Klamath Falls to Bieber. BNSF has trackage rights over SP (UP) between Chemult and Klamath Falls.

Western Pacific == Bieber to Keddie. Went to UP in UP-WP merger. Now part of the BNSF due to SP/UP merger.

Because of the jct between to railroads, there will need to be an joint interlocking of some sort at Keddie, and this will require signals, even if it is only a distant and a home signal on the Inside Gateway. The dispatchers are going to need some method of remotely authorizing movement from Keddie north, and the simplest method is for the BNSF dispatcher to control the (departure) Home Signal at Keddie that authorizes movement north.

Since there is no Northbound (railroad East) signal byond the Home signal, I know of only four possible signal aspects that could be displayed - solid yellow which would apply to a sign placed opposite the Distant Signal; flashing red; Lunar; and red over Lunar or Lunar over red (this last combination is usually used to indicate a facing point switch position so a train need not stop if the switch is porperly aligned).

It is also possible for the Home Signal for Eastward movement where the West Leg of the Keddie Y meets the Feather River Route Main to display a diverging route signal that would include Lunar and/or Flashing Lunar to authorize movement up the Inside Gateway and not have a "departure Home" signal where the two legs join to make the tail track (in this case, the Inside Gateway Mainline).

This signal would also need to act as a switch indicator for the tail track switch. If someone has a copy of the UP's Special Instructions that apply at Keddie, this would detail all of what we have been talking about here.
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Posted by MP173 on Thursday, April 6, 2006 9:47 PM
Just west of Valparaiso, In. the CN crosses the NS and the CFE. The CN controls the interlocking.

The NS line curves to the right beginning about 1/3 mile west of the CN crossing, making the signal difficult to see. At the beginnign of the curve is a road crossing. There is a signal just before the line begins to curve. This only has one lamp and is either red or lunar. This signal allows the on coming train to either stop short of the curve and the road crossing, or continue on and cross the CN.

Since the CN controls the siding if is highly probable that they will hold the NS (or CFE) trains if there is a CN train within 10 miles.

My guess is the lunar allows the crew to either stop short or continue at speed. I often hear conversations between dispatcher and crew in which this signal is referred to as the "lunar signal".

ed
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Posted by karldotcom on Friday, April 7, 2006 12:46 AM
I have seen a Lunar once on Metrolink territory......a train was givin one into a siding that was occupied about a 5000 feet ahead....

My train videos - http://www.youtube.com/user/karldotcom

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Posted by kenneo on Friday, April 7, 2006 6:03 PM
QUOTE: Originally posted by MP173

Just west of Valparaiso, In. the CN crosses the NS and the CFE. The CN controls the interlocking.

The NS line curves to the right beginning about 1/3 mile west of the CN crossing, making the signal difficult to see. At the beginnign of the curve is a road crossing. There is a signal just before the line begins to curve. This only has one lamp and is either red or lunar. This signal allows the on coming train to either stop short of the curve and the road crossing, or continue on and cross the CN.

Since the CN controls the siding if is highly probable that they will hold the NS (or CFE) trains if there is a CN train within 10 miles.

My guess is the lunar allows the crew to either stop short or continue at speed. I often hear conversations between dispatcher and crew in which this signal is referred to as the "lunar signal".

ed



Ed ... This is a "call-on" signal. Since the crossing is within 1/3 mile of the interlocking, I am sure that this signal is there to prevent a train from blocking the crossing. The red would mean stop right there and do no block the crossing. The Lunar would be the "call-on" indication to advance the train to the Jct signal.
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Posted by kenneo on Friday, April 7, 2006 6:09 PM
QUOTE: Originally posted by karldotcom

I have seen a Lunar once on Metrolink territory......a train was givin one into a siding that was occupied about a 5000 feet ahead....


Karl

This is a risky maneuver. As a dispatcher and also as a conductor, I have done this, but this has the same risk as crawling under a moving train. However, sometimes there is simply no other method to get trains moving - and there are lots of reasons why they are not moving.

Normally, when a train - even one car long - is in a siding (control block), NOBODY else is permitted to enter that block. But like I said, sometimes you do have to enter and the Lunar signal accomplished that --- it is a "call-on" signal with special restrictions.
Eric

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