Dear Dr. Gridlock:

I was driving on the Beltway at night recently and barely noticed a black car with no headlights. The car was very hard to see.

While I was behind this very dark car, I tried to signal by turning my own headlights on and off, but to no avail. In return for my efforts, the gentleman gave a rude gesture out his window.

It is obviously very dangerous to drive without headlights in the dark. My question for Dr. Gridlock is whether there is a way to signal another driver that his or her headlights are not on and should be.

Any suggestions how to handle this?

Margot Young

McLean

It is difficult to communicate with such a motorist if you are behind him. Turning your lights on and off quickly, or flashing your bright lights on and off, more often signals a desire that the motorist pull right so you can pass.

You might try pulling abreast, making eye contact and pointing to his headlights. Or you could call #77 from your cell phone (illegal on hand-held cell phones while driving in the District) to alert law enforcement of a dangerous situation.

Things being as they are on the roads these days, I suppose any well-intentioned attempt to communicate by hand could trigger a road rage incident. So after trying, I would drop well back and give this driver a wide berth.

I suspect most drivers are not aware they are driving without headlights and are grateful for the help of another motorist.

Do you folks have any other suggestions how to alert motorists that they are driving without headlights?

The Porsche Puzzle

Dear Dr. Gridlock:

I had to laugh when I read your question in the Oct. 23 column about the purpose of the red metal clamps on each wheel of the parked Porsche Boxster you saw.

I am guessing that what you saw was a Boxster S, which has painted red brake calipers (which grip the brake to stop the car) to add a sporty look to the car.

Most cars have black calipers and go unnoticed, but the red paint draws your eye to them, and people often ask what they are.

Jamie Reed

HBL Porsche of Tysons Corner

Vienna

Thanks. Clearly I need to be around more Porsches.

Getting From There to There

Dear Dr. Gridlock:

I recently spent a wonderful week's vacation as a volunteer for the President's Cup golf event in Prince William County. One of the perks of volunteering for the event is being able to play a round at the famous Robert Trent Jones Golf Course.

To make a long story short, what time would I need to finish a Monday round and be back to Baltimore-Washington International Thurgood Marshall Airport to catch an 8:30 p.m. flight?

Pat Corbett

Queensbury, N.Y.

I suggest about 3:30 p.m. You're probably going to run into some rush hour traffic, and you'll want to arrive at the airport one or two hours before your flight. One route is Interstate 66 east to the Capital Beltway's outer loop (because of Montgomery County congestion), to northbound I-95 in Maryland, to I-195 in to BWI. Good luck!

Deer on the Prowl

The combination of deer mating season and the fact that it is dark earlier now should remind us to watch for deer bolting onto roads. They are unpredictable and can be in front of a driver in the blink of an eye.

A file of six ran in front of me once on a dark two-lane road lined by forest. Although I braked, I clipped the back of the last deer. After I found a place to pull over, a motorist trailing well behind me said the file immediately turned around and ran back across the road. He said none of the deer seemed injured.

The National Safety Council reports that in 2003, 530,000 animal-related vehicle accidents resulted in 100 deaths and 10,000 injuries. Most of the animals were deer.

Online Chat

Dr. Gridlock will host another online chat Monday on www.washingtonpost.com/liveonline. I'll start taking questions about noon and will post answers and go live from 1 to 2 p.m.

This is another forum for questions and comments about our transportation system.

Transportation researcher Diane Mattingly contributed to this column.

You can write to Dr. Gridlock at 1150 15th St. NW, Washington, D.C. 20071. He prefers e-mails to drgridlock@washpost.com or faxes to 703-352-3908. Include your full name, town, county and day and evening telephone numbers. Dr. Gridlock cannot take phone calls.