Hmmm, the NHTSA-NASA Study of Toyota Unintended Acceleration

I took a quick look at the 177 page NHTSA-NASA Study of Toyota Unintended Acceleration full report this evening. I had hoped that with NASA involved, it would have been a really hard core report. Sadly, the design of the experiments aspect of it appears to so financially and resource constrained, it seems to raises more questions than answers.

For sure, the obvious things tested for in published standards are ruled out. In addition, the human factors analysis appears well done, albeit such is mostly outside the scope of my expertise. Perhaps the biggest disappointment is the lack of detail provided… yes, its likely written for politicians, rather than EMC engineers, but being NASA, I guess my expectations were a lot higher than reality.

Since I have a number of years in the EMC field, I’ll take a look at section 6.8 My guess is there are likely substantial internal NASA discussions on these factors, albeit they didnt make it into the report.

Sample size:

Six vehicles were chosen for testing, all of which were reported to experience UA… Sounds good, but none of them have the same option set, and the years 2005 and 2006, were skipped entirely. Granted, I am not familiar with Toyotas, but I would certainly expect substantial year to year variation.

Frequency range of radiated susceptibility testing

The frequency range of testing lined up with ISO, Toyota, and NESA standards, and on the outset appear a good thing. However, there is a gap between conducted and radiated susceptibility tests (its a royal pita to test there, standards dont require it, and its rare in todays world to have problems in such an area… but I’ve run into it before (science is no respector of standards)).

Dyno testing

Units were tested on a dyno… and a dyno that can withstand 250V/m radiated fields, without causing distortion in said field has to be a really really cool device. On the other hand, in likely trying to avoid killing the dyno, its design probably shoots a number of anomalies into the field surrounding the car (Granted, I’m not sure I’d want to drive a car while subjected to a 250V/m field for an extended time… but it is a test limitation to consider).

High Current Audio Injection Failure precluded some testing

NHTSA-NVS-ETC-SR15 failure report is not included… perhaps the high current failure was an anomaly, perhaps not. Granted, the audio injection test is an unusual one. On the other hand, why did 4 pass, and 2 fail?

Also, being a 3300rpm increase was detected at 2Vpp at 150Khz… perhaps this test should have been run on more than 1 vehicle? Granted, outside of the test lab, such should never occur, but it is a point of interest. I’m a bit surprised testing was not explored at 125Khz, as such has repeatedly bit me in the field over the years. Likely civil litigation will explore this further with differing power levels, and/or frequency sweeps.

DTC Issues

Its assumed that DTC’s which were triggered were reliably recorded. Ie a Toyota Tech Scan was attached and data was pulled before, and after testing. (Obviously having it connected during tests would either kill it, and/or potentially disturb the results).


Orientation was limited to 1 orientation for the TEM cell, and 8 orientations for the semi-anechoic. Such seems a reasonable approach, on the other hand… which orientation for TEM cell setup? Were other orientations possible?

Tests not performed (see table 6.8.1-1)

Early failures of vehicles 13C and 14C precluded many tests, and the fact that so many tests were skipped is a cause for concern.

The victim terminology

This is just a point of interest. Years ago, the usage of the terms source and victim were discouraged, as the legal field would tend to run with such. I gotta admit it is nifty seeing such terms once again.

The lack of any discussion or test data concerning ESD

On the outset, short of a minor discussion in section 6.9, this is not mentioned. The ToC suggests that data is available in appendix B, which is pretty nebulous as well. Section 6.9.6 is not a confidence booster, and such does leave the door open for civil litigation. Granted a Camry is not the space shuttle, but I bet the NASA guys were going WTF when they saw the watchdog/heartbeat monitor setup.

The observations in section 7.1

These are interesting…

sample size again is a concern

F-3. At full throttle, brake vacuum boost can be diminished or lost (apparently unlike Nissan of 20 years ago, they dont see the need for an auxiliary vac pump for such situations). It was also interesting, that even with the vacuum boost lost, one can decel at 0.25g with 112lbf on the brake pedal at 30mph. I wonder what the deal is a 75mph?

F-5 Tin whiskers… no wonder Uncle Sam and aerospace is exempt from Rohs. At least Toyota expected this might happen and designed around it. The big question though, is what if the whiskers show up in other places, and what about other manufacturers?

O-3, and O-4 are interesting… yes, the smog stuff is important, but I’m not sure its wise to not hold safety to a similar standard.

O-7 and O-8… yep, this is a problem. If I had a Camry, I’d code up an Iphone app to address this exact situation. If they really want to get to the bottom of it, wide scale testing either via an Iphone, Android, or something related might be a cheap and fast way to explore this aspect.

O-11, I agree 100%… even more so if the driver is tired, and its a different vehicle than what they normally drive. Ie a rental car fleet an airport might well provide for a great study of this human factors issue.

7.3-R-1 Likely they wont approach any of the concerns presented in this report, until either something really high profile occurs, or as the vehicles age, more problems show up.

My conclusion

Most of the obvious issues have been ruled out, or put in the category of being statistically low probability events. This does not mean there isnt some type of anomaly, but that if there is, it will be rare, and it will be a really bugger to get to the bottom of it. The biggest deal to me, is that so many of these issues transcend the whole industry, Toyota just happened to get in a jam mechanically (floormats, and/or brake pedal sticking) which put them in the spotlight.

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FAA user fees, differences between McCain and Palin

ts interesting to note the differences of opinion over FAA user fees. From MPR: News Cut: Blaine setting for Palin speech highlights a difference with McCain

Senator McCain…. “I wanted to get at, which we should get at, the wealthiest people in America who are flying corporate jets around this country and not paying an extra penny for doing so, while average citizens, average middle income, lower income American citizens are paying, again, an increase in their cost of air tickets, while your fat cat friends pay nothing. ”

McCain stressed that user fees would only apply to business aircraft. The general aviation interests insist that a user fee-funding system would only expand.

Gov. Sarah Palin…..signed a resolution in Alaska in 2007 that opposed “the enactment of the provisions in the Next Generation Air Transportation System Financing Reform Act of 2007 that impose user fees, increase aviation fuel and aviation gas taxes, reduce airport funding, and reduce Congressional oversight of the Federal Aviation Administration.”

“Aopa… says the surplus in the Aviation Trust Fund, paid for by taxes on general aviation fuel, airline passenger tickets, and cargo, should be used instead, and argues that the skies will be less safe because pilots won’t use air traffic control and other services designed to keep flying a relatively safe exercise.”

Indeed, I think this is a safety issue. GA pilots are cheap, and will do pretty much anything to save a buck, esp when they figure it cant happen to me. 25 years ago when I worked on GA airplanes, man the stories I could tell. As a flight instructor for nearly 20 years, my mechanic experience was continually reinforced. If pilots start having to pay for services, its likely the vast majority will choose to not use them, and safety will be affected. Its not unlike the reluctance of pilots to declare an emergency… with the end result being a crash and potential loss of life, and thats over the paper work burden. Imagine if they had to spend $25 to do so…. Declaring early brings a wealth of resources, waiting until the end, it can be too late, and or the number of remaining options end up being severely limited.

Now, some might say, pilots need to take responsibility…. ie if you go cheap, and something happens, its your problem. The issue is, things dont operate in isolation and the public is affected. A runway closure due to a crash can put an airport out of service for hours, if not days of reduced capacity. A search and rescue effort costs tons more than a weather briefing. A midair is a lot more expensive than a years worth of flight following/radar services. to say nothing of loss of life.

The other issue is FAA services for the most part are a fixed cost. Ie, once weather services, air traffic control, and airports are in place… they are fixed costs pretty much with the exception of usage. The exception being peak hours at busy airports and terminal areas where additional technology and staffing are needed. Yet for the vast majority of airspace, and airports the costs are pretty much fixed. Since the largest user base contributing to the peak times are the airlines, it only makes sense they should cover a majority of the costs. Now, whether the 97% figure is the appropriate number, that’s another story entirely.

Granted… McCain states this would be for business aircraft only, but just as the NRA is against some seemingly reasonable restrictions as concerns gun control… its not the initial concept as presented, its the slippery slope which can lead to huge problems later on which is the issue. The last thing general aviation needs is a user fee taked onto small training aircraft, which likely would increase operational costs by 30-50%, to say nothing of the negative safety aspect. Sure, a lost flight student is going to use ATC services… but again, some ATC radio help is a ton cheaper, than the manpower, fuel, and aircraft needed in the event search and rescue is needed.

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Legislation to encourage bicycle commuting

GovTrack: H.R. 5351: Text of Legislation passed the house

The Renewable Energy and Energy Conservation Tax Act of 2008 has a provision to encourage bicycle commuting. In fact, employers would be able to offer a tax exempt fringe benefit of up to $20 a month for those who commute by bicycle.

Granted, being I coordinate virtual teams in my business, who don’t commute, and are not employees, the ability to offer this fringe benefit has limited value to me, other than it will reduce emissions. If I ever decide to go the route of onsite employees again, this is something I will have to highly consider.

Years ago, one of my techs, as well as a co-engineer used to commute by bicycle. Even I had to prove it to myself I could do so… on one of the coldest days of the year. I figured if I could ride 3.5 miles in -23 deg F weather, I would have no excuse for not doing so on any other day. Well, I didn’t bicycle commute very often, but it did convince me it was possible.

Thus, I think this is a great addition to the bill. The cost to the govt is pretty low, the cost to employers who choose to offer it is pretty low, and apart from reducing carbon emissions, it is likely to also result in lower medical costs, and even efficiency gains due to healthier employees. Its also one of those fringe benefits that can give an employer an edge when it comes to recruiting. Not so much from a benefit standpoint in and of itself, but that an employer is on the ball, and wants to encourage energy conservation, as well as improved employee health… and such a stance can make a difference when it comes to recruiting, at least in some sectors.

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