Texas Exhibits

TX1 Arizona Driver License Handbook

Texas Drivers Manual (2012)

Feb 21, 2014
TX2 Texas Commercial Motor Vehicle Driver Handbook

Texas Commercial Motor Vehicle Driver Handbook, pp. 2-15, 5-6

The conflict in regulations between the Texas Department of Public Safety (TxDPS), the TxDOT and the National Cooperative Highway Research Program (NCHRP) entraps commercial motor vehicle drivers, forcing a much greater percentage of such drivers to run red lights. Commercial vehicles are school and public buses, and tractor-trailers.

1. The Texas Department of Public Safety (TxDPS) states that commercial motor vehicle drivers require at least 1.5 seconds for perception and reaction time. The TxDOT grants them only 1 second (exhibit TX4).

2. On p. 5-6, TxDPS states that commercial vehicles with air-brakes also require at least an additional 0.5 seconds for air-brake lag time. It takes at least 0.5 seconds for the air to build up so that the brakes work. These perception/reaction and air-brake lag times are in agreement with the handbooks from other States.

3. The TxDOT expects all vehicles to safely and comfortable decelerate at 10 ft/s/s (exhibit TX4). But the NCHRP shows that the best truckers can only do 8.0 ft/s/s (exhibit TX3).

The TxDOT ignores these differences when setting of a yellow light duration. Engineers regard commercial vehicles as a minority on the road, summarily dismissing them because it would be inconvenient to the rest of the driving world. A longer yellow light would be that some traffic would not move as efficiently as before.

These arguments date back to the 1950s. Traffic engineers have not changed. Engineers care not for the little children in a school bus or the driver who might get fired from his job for getting a red light camera ticket. As far as safety is concerned, traffic engineers believe that these vehicles are so big every one else will just get out their way. As far as forcing drivers to run red lights, traffic engineers fault the city for penalizing such drivers. This sort of attitude prevails in the legal depositions of North Carolina traffic engineers. (See North Carolina Exhibits.)

TxDOT sets the yellow timing as if all vehicles are a Toyota Corolla driven by an alert 25 year-old on dry pavement. Texas physically forces every one else to run red lights. The commercial vehicle drivers get the shortest end of the stick. Though Texas allows the vehicle on the road, the TxDOT's designs do not. The TxDOT shorts the yellow at least 2.0 seconds of a trucker's minimum need.

Feb 21, 2014
TX3 NCHRP-505: Review of Truck Characteristics in Roadway Design

NCHRP-505: Review of Truck Characteristics in Roadway Design, p. 48, Table 26

The safe and comfortable deceleration rate for the best commercial vehicle drivers is 0.25G, or 8.0 ft/s/s, when driving an empty tractor-trailer on wet pavement.

Texas does not care. The TxDOT assumes all vehicles are Toyota Corollas--that everyone can do at least 10 ft/s/s.

The biggest concern for truckers is jackknifing. When braking harder than usual, they worry about the vehicles traveling at their sides.

Feb 21, 2014
TX4 Texas Yellow Change Interval Formula

Texas Traffic Signals Operation Handbook, p. 2-16

The conflicts between TxDPS, the TxDOT and the NCHRP entrap all commercial drivers, including school buses, public buses and truckers. By design, the TxDOT puts all these vehicles in harm's way, including the children, all for the sake of traffic flow.

The TxDOT sets the yellow light using a perception/reaction time of 1 second. This is at least 0.5 seconds short of what the TxDPS states that commercial drivers need.

The TxDOT does not include air-brake lag time in the yellow light formula. This always shorts the yellow for a commercial driver by at least 0.5 seconds.

Feb 21, 2014
TX5 TxDOT Report 0-4273-2

TxDOT Report 0-4273-2: Yellow and Red Intervals to Improve Signal Timing Plans for Left-Turn Movement, p. 28

TxDOT report 0-4273-2 is one of the most intellectually dishonest papers ever written.

The author is Dr. Lei Yu of Texas Southern University. Yu surveys traffic engineers in order to establish what criteria to use to compute the yellow light duration for left turn lanes. On p. 28, Yu concludes that "Traffic laws relating to signal-controlled intersections" takes 7th priority. In other words, whether the yellow makes drivers run red lights takes 7th priority.

Efficient flow is first priority. Flow is the underlying theme of the entire paper. After flow, the paper's survey says that safety is the next priority. Legal movement of traffic comes at a distant 7th.

When traffic engineers design an intersection, allowing traffic to move legally is the least of their priorities. This comes as a surprise to the general public. The public presumes that engineers actually care whether drivers run red lights. But they do not! For decades, engineers plan their intersections so that drivers move efficiently knowing that they sacrifice legality.

If one doubts that the 7th priority infers that engineers care not for whether a driver must run a red light, then read on.

Yu, the author of TxDOT report so happens to be a coauthor of exhibit TX5. Yu wrote TX5 before the TxDOT paper. TX5 is an American Society of Civil Engineers (ASCE) peer-reviewed paper. Its title is Determination of Left Turn Yellow Change and Red Clearance Interval. The conclusion of the ASCE paper is that left turn yellows must be longer than the straight-through yellows so that traffic can enter the intersection legally.

But to appease the wishes of the State of Texas, Yu disregards his earlier paper's requirements for legal movement and goes ahead and shorts all the left-turn yellows to values far less than the straight-through. Yu knows all along his TxDOT report is forcing drivers to run red lights. But like all traffic engineers, Yu does not care. Yu does not bring out this contradiction in the TxDOT paper. He neither notifies TxDPS nor Texas law enforcement that his standard forces drivers to run red lights.

Feb 21, 2014
TX6 Determination of Left Turn Yellow Change and Red Clearance Interval

Determination of Left Turn Yellow Change and Red Clearance Interval, p. 1

"Left turn yellows must be longer than the straight through yellows." That is abstract and conclusion of this paper. The formula for legal turning motions is equation 13 on page 454. The formula comes from Newton's Second Law of Motion. We show the work on how to arrive at this formula in our paper "Derivation of the Yellow Change Interval Formula."

Traffic engineers disregard the laws of physics on page 454. By doing that engineers put people's life, heath and property directly in harms way. That is a violation of Texas's statutory requirements for professional engineers. See exhibit TX6.

Feb 21, 2014
TX7 Determination of Left Turn Yellow Change and Red Clearance Interval

Texas Professional Engineer Requirements, p. 8, p. 57

All traffic engineers who determine yellow change intervals in Texas violate Texas Statute 1001.003(b) (p. 8) and 137.51 (p. 57). These are the requirements for Texas' professional engineers. The engineers not do not know the mathematical and physical sciences to do their jobs, and when they do, they ignore them.

Look on page 57, section 137.51. In the very least, consider red light camera fines as property.

Feb 21, 2014


Texas Opponents of Red Light Cameras

TX-L1 Houston Coalition/Sugarland--Capt. Van

Houston Coalition/Sugarland--Capt. Van

Dec 16, 2012
TX-L2 Citizens Against Red Light Cameras

Citizens Against Red Light Cameras

Nov 4, 2012
TX-L3 League City Camera Scam

League City Camera Scam

Nov 3, 2012