Blackout driving light

[cranetruck]

Does anybody have an "official" view of the illumination pattern of the BO driving light as seen from the side? I'd prefer a diagram from a TM if possible.

Thanks,

 

[cranetruck]

Found this statement while researching the matter:

"...The lamp also had a metal hood similar to a baseball cap’s bill built in to it to make it invisible from the sky. The name B/O Driving Light confused many people. The main purpose was not to help the driver see the terrain; rather it was for the people driving ahead of you. Your B/O Drive Light was right in line with the outside rear view mirror of the guy in front of you. As a driver, if you saw a rapidly approaching Black Out Drive Light in your rear view mirror, you could tap your brake lights as a warning or take evasive action as necessary. It would also allow pedestrians a better chance of seeing you coming and get out of your way. It’s value as a way of seeing where you were going is next to nil. B/O Driving lights became standard issue starting in mid 1942...."

Anybody care to comment? I had no training in blackout driving or convoying and would like an expert's opinion, please.

 

[alphadeltaromeo]

Although I don't have anything to add that would be beneficial to your question, I will say that I appreciated the last portion, as I wasn't clued in to the actual function of that light. Appreciated!

 

[emmado22]

I've done more Night Vision convoy driving at night than I care to remember, both leading and following. The lights, as stated are not for the driver to see by, but to see the truck infront or behind you. With the red brake lights, there are actually 4 "slits" per brake light. When you see all 4, your too close. When all 4 look like 1 light, your too far back. When you only see 2, your right on the money distance wise. For the front BO "drive" light WITH the use of Night Vision Googles, it casts plenty of light to drive at 5-10 MPH cross country... Any faster, and your asking to crash due to reduced depth perception. Hope this helps.

 

[cranetruck]

Thanks Mark.
The reason for asking is that the blackout driving light on the xm757/m656 trucks WITH winch is sometimes mounted behind the extension that holds the winch and the headlight assy's and would not illuminate the ground very well for the the driver of that truck.

 

[cranetruck]

This was written by "MilitaryLightMan" in a different thread:

"...Lastly, concerning the LED Blackout Drive lamps, there is no comparrison to the Grote Lamp. The older incandescent versions put out very little light and were terrible to drive with. The Truck-Lite version was a vast imrpovement over the older incandescent lamps, however there were still some "blind spots". Grote took the newest technology available and (within the STANAG Agreement) was able to put more useful light out in front of the vehicle. (Especially noticeable when turning corners and wearing NGV's)..."

Emmado, how does the above statement jive with your experiences?

Sorry folks for all the digging here, but that is just the way I am.

 

[ARMYMAN30YearsPlus]

I can't match Emando22's thousands of hours but have driven enough with both PVS7, PVS 14 and PVS 5's to tell you that it is such a vast improvement over driving with just BO drive. Once you see the capability of a GEN III or higher intensifier tube you will never want to face the night without one. The sad thing is most of our LEO's do not have them in their patrol car at night. When I was a Company Commander I used to sign out a pair of PVS7's and take them to the local LEO chief and arrage a night demonstration of hide and seak with the goggle versus with a standard mag light. The officers all wanted them and they deserve them if they are patrolling at night.

In Iraq the night belongs to our Soldiers because of the PVS and TVS series of night vision. There are lots of commercial spin offs of these now and all it takes is money to get them. That is why our Police need them because if a rich drug dealer has them they should too.

Driving with the NVG's or the PVS 14 takes some getting used to because the depth perception is different viewing through a single tube. For years the pilots used the older two tube versions rather than the newer PVS 7 just for that effect.

Bottom line is driving with BO is a slow go affair without NV with and with training it is possible especially with additional IR illuminators to drive as fast as daylight driving.

 

[rmgill]

Of course this all goes out the window with convoy ops at night with out NVG's or before they were issued (say like WWII). The Blackout light on my Dingo has the hooded aperture and has a flap that allows a front facing aperture to be opened.

the British also illuminated the white painted rear differential on their vehicles with a lamp so the driver behind could see.
Like so

 

[houdel]

Re: RE: Blackout driving light

Found this statement while researching the matter: "As a driver, if you saw a rapidly approaching Black Out Drive Light in your rear view mirror, you could tap your brake lights as a warning or take evasive action as necessary..... B/O Driving lights became standard issue starting in mid 1942...." Anybody care to comment? I had no training in blackout driving or convoying and would like an expert's opinion, please.

Maybe in 1942 the brake lights still worked in conjunction with the brake lights, but I believe on more recent vehicles the drive, tail lamp and brakes lamps do NOT work when the light switch is set to the B/O position.

I agree with emmando22; we used to call the rear B/O lamps "Cats Eyes". The four elements in the rear B/O were designed to provide varying optical illusions depending on how far you were from the preceeding vehicle. If you could only see two bars you were at the right convoy distance. If you could see all four bars you were too close, if you only saw one bar you were too far back.

The front B/Os didn't provide very much illumination, just enough to stop in time if there was a big obstacle or body lying in the road ahead of you, and only applicable to the lead vehicle. The following vehicles drove mainly by watching the "Cats Eyes" on the vehicle in front of them.

 

[ARMYMAN30YearsPlus]

RE: Re: RE: Blackout driving light

I spent a lot of night convoys pre NVG days slapping myself to stay awake in BO drive not fun memory in the woods of Germany or at Fort AP Hill

 

[m38inmaine]

The brake lights still work in the black out drive position, they are of course subdued like the taillights. The early M416 jeep trailers and jeeps(pre composite lights)had a seperate "bullet" light mounted above the right side taillight for the blackout stop light, the newer composite lights have it built in. I spent alot of time on night ops with a transpertation company I was assigned to, the blackout drive light is no help for forward illumination as stated before.

 

[cranetruck]

Tested my "new" BO driving light on my basement work bench last night. It illuminated the basement like a flashlight would, but somewhat less intense. No problem walking around in that light with the floor and boxes and stuff clearly visible. Things higher up (off the floor) were only visible from indirect light.

Ducking down and looking right at the lens of the BO light even from 20 feet away is a no no since it's very intense and will ruin one's night vision.

I can see (no pun intended) driving by this light and know my son did it from time to time in his M37 on our dirt road at night, just for fun (no traffic, of course).

I don't want to consider nightvision aids in the context of vintage nighttime ops, they change everything.

Thanks again to David (Armyman30yearsplus) for providing this lamp.

 

[NEIOWA]

I can't match Emando22's thousands of hours but have driven enough with both PVS7, PVS 14 and PVS 5's to tell you that it is such a vast improvement over driving with just BO drive. Once you see the capability of a GEN III or higher intensifier tube you will never want to face the night without one. The sad thing is most of our LEO's do not have them in their patrol car at night. When I was a Company Commander I used to sign out a pair of PVS7's and take them to the local LEO chief and arrage a night demonstration of hide and seak with the goggle versus with a standard mag light. The officers all wanted them and they deserve them if they are patrolling at night.

Actually, since 9/11 DHS grant $ have puchased boat loads of NODS (and civ MPO gear, auto weapons, high tech commo equipment). CEDAP program gives the stuff out (no local $ required). The stuff that goes in the trunk of a squad car, at best but more likely in a storage locker somewhere. The 90% cops don't know/aren't trained on how to use it. The average policeman doesn't even draw his weapon on a range more than once a year. On average don't jump right into taking on new project even if the Feds throw nifty high priced stuff to them, it's a shiftwork job little more.

Late 80s 9ID SOP for NODS was driving in full blackout (no lights at all).

 

[acetomatoco]

When we convoyed in the black forest of Deutchland in the 60s...in blackout conditions, only the lead vehicle in each serial was allowed to use the blackout drive light... the markers only were for the rest...It was the blind leading the blind and...with none of that new fangled stuff... The lessons with spacing and speed discipline were very enlightening and not a few of my associates would up buying trees and fenceposts. The bridge trucks and cranes were among the biggest offenders... I remember being captured by the Russkies..OPFOR...and setting up an escape..barefoot...they took our Combat Boots...and hitting trip wires and setting off flares... Got to see the BNCo, a Colonel, to explain myself and got a nice letter of commendation in my 201 file....... and now back to the B/O... I would not want to see the BOD light of the the vehicle behind me in my mirror as it would ruin my night vision for minutes at a time... and the ability to see the b.o markers and b.o. brakelight of the vehicle in front of me would be compromised...speed in b.0. conditions is limited to walking ...3 or 4 mph max... ACE

 

[cranetruck]

Thanks ACE for that post! It's the kind of confirmation I was looking for, just studying an individual component causes a lot of speculation, if you know what I mean. It also puts the front BO marker lights in place.

 

[carguy455]

Hey RAM that sounds like a great story, you should post that in another thread, would love to hear all the details.

The "blackout" driving I did landed me in A.A. and cost me my license for 2 months a few years ago....

I like everyone elses version on here much better.

 

[cranetruck]

The original design of the M656 series puts the BO driving light inboard, later modifications placed it outside/in line and above the BO marker lights. Confusion set in.

 

[11ACR-LT]

The aiming instructions in my manual for my '42 MB state with the vehicle level and the hood on the light level place a 4 foot stick at the fender and mark the stick where the bright spot appears,move the stick 10 feet ahead of light and adjust light so that the bright spot is 2.1 inches below the original mark. aimed this way the light won't shine in the lead vehicle mirror. they're only supposed light vertical objects( trees,people). only lead vehicles used B/O drive as I remember.

 

[jld66]

ACE got the explanation for the BO drive the best. Before NVGs only the lead vehicles used The BO Drive Light. The night convoy move at walking speed. A ground guide walked ahead of the lead vehicle in the light pattern of the BO Drive light. That is why there is only one and it is on the drivers side. As previously explained the "cats eyes" were used by other drivers to judge distance and position of the vehicle ahead and behind by the pattern of the lights. NVGs were not widely available, especially in medical units when I retired. I would assume that night convoy ops are a little different now with NVGs.