anyone seen the radar guns on the lightpoles on I-95

[odortiz]

on a few lightpoles between northbound and hov on I-95, there are radar guns aimed at traffic and fire off k-band radar for a few seconds every 10 seconds or so. they have a little solar cell above them. they are placed about 20 feet from the ground.
i've seen them in my drive from woodbridge to alexandria.
anybody know what they are for?
anybody else seen them?

[OwnedbyDuncan]

It is a classified DOD/DHS project. Details will appear shortly in the MSM because of a leak. It deals with a possible WMD attack by terrorists and pizza delivery.

Dave Apker

[AlfaEric]

on a few lightpoles between northbound and hov on I-95, there are radar guns aimed at traffic and fire off k-band radar for a few seconds every 10 seconds or so. they have a little solar cell above them. they are placed about 20 feet from the ground.
i've seen them in my drive from woodbridge to alexandria.
anybody know what they are for?
anybody else seen them?

I'm guessing they collect traffic speed data.
http://www.chart.state.md.us/TravInfo/speedData.asp

---Eric

[1996 328ti]

Kinda tells you that the speed limit should be 65.

[AlfaEric]

Kinda tells you that the speed limit should be 65.

At times I think they should just remove the limits on some roads. Seeing a speed limit sign while going 5 mph on the highway in traffic just pisses me off.

---Eric

[Pinecone]

Kinda tells you that the speed limit should be 65.

Or higher. Notice they don't report an actual speed above 65?

[ob325]

on a few lightpoles between northbound and hov on I-95, there are radar guns aimed at traffic and fire off k-band radar for a few seconds every 10 seconds or so.

They are on 395, too. I hate them. But it's not like I can write anyone and complain about that. I test my reaction time to see how quickly I can silence the buzz.

And what good do they do? Whenever you see the "average speed" reported on TWC or the news, it is never above 54mph, yet I've been on there many times when everyone is going 65+ easy.

[odortiz]

between woodbridge and alexandria at about 8 pm, everyone northbound travels about 80-85

[JCFLYS]

They call them Radar Drones in California. Its just another way to piss us off. It sets of your detector if you have one and must be part of their agressive driver imaging program.

[mlytle]

They call them Radar Drones in California. Its just another way to piss us off. It sets of your detector if you have one and must be part of their agressive driver imaging program.

yep. connecticut has them every half mile or so on i95 from new york to new haven. render radar detectors effectively useless.

[David Hicks]

I've been going slower to save gas recently. At 60-65, you better be in the right lane of these roads (I 95 and I 395 in VA).

[Dirichlet]

I've been going slower to save gas recently. At 60-65, you better be in the right lane of these roads (I 95 and I 395 in VA).

odd... I find that my car is most efficient at about 80mph, where I get 29-30mpg...
I'd like to see an actual efficiency/speed curve of the average modern vehicle - I'd be willing to bet that the most efficient speed isn't the 50-60mph they'd like us to believe. If the typical 70's through mid-80's car (shaped, effectively, like a brick) was most efficient around 50mph, I'd be willing to bet a hefty sum that the average car today operates best around 70mph... again, I have no proof of this, save what I have observed in my car, but it would be interesting to see.
(it may also be the anarchist in me getting pissed when I see the signs saying "slower speeds save gas" - I don't like the man trying to slow me down by capitalizing on current oil price economics... )

[David Hicks]

It doesn't matter how aerodynamic your car is - drag increases with the square of velocity.

I wish I had time to do a little more research and really respond, but I'm swamped. You might be right that 55 mph is no longer the ideal speed, but I'd be very surprised if it were as high as 80. I've found the key to good mpg is to drive downhill as much as possible.

[Dirichlet]

drag increases with the square of velocity.

True

It doesn't matter how aerodynamic your car is

False
The total force of air friction (drag) is given by
f = .5*C*A*V^2
where A is the area and C is the numerical drag coefficient. The point I was making is that today's vehicles have a greatly reduced coefficient of drag (C*A). Thus, for the same force (load on the motor), you can achieve a higher velocity...
Let's take a car with Cd = 0.6 v.s. a Cd= 0.5... the car with the lower Cd would be as efficient (given the same engine) at 66mph as the higher Cd would be at 60.

[Pinecone]

And there are differences in the efficiency curves for the engine versus RPM and with gearing, the higher speed may get you into a more efficient area of the fuel use curve.