"If your car is going to have an accident, the best situation is if it happens when you are not in it!" And that is just what happened to me yesterday. I have been doing some work on my house recently, and came home on my lunch break to see if the floor guy (who is patching in a new oak board to replace one that rotted out due to water damage from a leaking bathroom wall) had been there in the morning, so I could release the beagles from where I keep them confined when workmen are there. Since the front door was unlocked, I parked curbside in front of the house.
The contractor had not yet been there. I was warming some food in the microwave when I heard a very loud impact noise from the street. A full-size pickup truck had come over the curving hill above the house and slammed into the rear corner of my car, doing considerable damage to both vehicles. The sad part was that I knew the guy: He is my maintenance gardener. After we exchanged insurance identification, I replaced the cut-up left rear tire with the doughnut spare wheel and took the car to the body shop most favored by all the insurance companies. The impromptu comments led me to conclude that I am going to need a new car.
So this morning I went to look at the three most likely replacements for my 11 year old Mustang convertible:
- a Smart FourTwo Passion Cabriolet (the smallest convertible I know of)
- a Prius (I have wanted an excuse to test drive one for the last 5 years)
- a Volvo C70
Very different wheels, for sure, but each resonates with different desires.
I decided that the Smart is an overpriced Golf Cart. While it is totally adequate for my daily commute 8 miles each way, I would probably not want to drive it to Los Angeles (2 1/2 hours) or San Francisco (5 hours), but would need a rental for that. The salesman pointed out that the Hyundai Elantra gets the same miles per gallon as the Smart. (By some coincidence, the two marques are in the same dealership.) He did not actually have any Elantras in stock, but wanted me to come back when he gets some in 9 days.
I liked the Prius exactly as much as I thought I would. The salesman thought he could get one with exactly the features I wanted (white, trim level 4, and with a moonroof) but warned me that supply may soon become very tight due to the recent events in Japan.
And I loved the Volvo. To my surprise, they had 3 in stock (one each red, black, white), although the only color I liked was the white, which happened to be less expensive, being a left-over 2010 model. It drinks 50% more gas, and costs 25% more than the Prius, but it is very lovely. Having driven a convertible for a few years, I can appreciate how much nicer this one is: Better seats, folding hardtop instead of nylon hide (less noise), etc etc. The Mustang is cheap, the Volvo is nice. If I was ordering one from the catalog, I would take the stick instead of the automatic, and I would take the wood panel inlays. But a catalog order has to come all the way from Sweden, so I'd have to wait 6 weeks ... and probably have to pay the sticker price.
It is lovely to have a week to mull over this decision, and reflect on what "statement" each makes. I mentioned to one female friend that I had looked at a Volvo convertible, and she instantly wanted to know how many miles it gets per gallon, and how I could possibly find anything below 30 mpg to be acceptable. It is a fact that the parking lot at my church is about 30% Prius already.
Saturday, April 2, 2011
Friday, April 1, 2011
GPS in Aviation
My old friend G.G. who is a recreational pilot in Northern California offered me this supplement to the mailing list version of my previous post:
GPS is wonderful and seductive. It is no surprise that general aviation pilots like it a lot and that it has gained a lot of use far faster and wider than the safety community is comfortable with. Many legislators have been clamoring for replacing the aging instrument landing systems used by civil aviation with GPS based systems that could integrate tighter with on-board systems on modern airliners. But there is a big worry about reliability, especially the fact that a small jamming transmitter can very effectively disable GPS within its surrounding area. That sounds far-fetched, but is actually a very real risk.
The trucking industry has embraced GPS for fleet monitoring systems. A GPS receiver with a cell phone modem allows a trucking company to keep track of where its vehicles are moving. This is good for keeping customers informed about whether the load is moving on schedule, but it also allows a degree of supervision over the drivers that bugs many of them out of their skin. They like to think that when they are on a week-long cross-country trek with a load, they are lone warriors on the high range, masters of their own day-to-day life. But the GPS tracking device lets the company know exactly where they have been, and where and when they have been stopping. If they schedule an evening meal break in the parking lot of Gilley's dance hall on Saturday night, it is likely to result in some trouble. Much better for the driver if the device is somewhat unreliable, and fortunately, that can be arranged. Ads in the back of truckers' magazines offer a $30 device that plugs into the vehicle's cigarette lighter socket and transmits pure noise on the GPS radio frequencies. That will disable the GPS devices on the truck, and often all the other GPS devices in a half-mile radius around it. This turned out to be the cause of a lot of malfunctions in an experimental GPS instrument landing system that was being tested at Baltimnore-Washington International airport a couple of years ago.
"It might be unclear to your readers that the WAAS correction, while created from stationary receivers on the ground, is in fact (IIRC) broadcast by a subset of the GPS satellite constellation. Satellite failures can create areas where WAAS isn't available until the constellation is either adjusted or a new satellite is deployed.
I've an IFR certified WAAS GPS navigator for flight, and the accuracy seems generally within centimeters. Awesome performance. The WAAS navigators are also required to have a 5Hz update rate, which allows them to synthesize glideslopes, allowing ILS-like approaches for most airports.
The only problem for aircraft is that Jeppesen is the monopoly provider of GPS databases of enroute and arrival/departure procedures, which now cost ~$450 a year, vs. Free to use the old terrestrial navaids. And Garmin, who couldn't quite get their GPS designs to operate to WAAS standards, were allowed to buy their only competition, UPS Aviation Technologies, to get their hands on a WAAS solution. They stopped development of the UPSAT offering, the CNX80, relabeled it the GNS 480 but never delivered all of the advertised features, used the now Garmin AT office to port the good stuff over to look like the Garmin GNS 430/530 operations, and then quietly announced they were immediately dropping the 480.
BTW there is a free public aviation navigation database, but Garmin is making good money in partnership with Jeppesen and refuses to make the public database available. Not an open format, needs compilation to be usable.
GPS is wonderful and seductive. It is no surprise that general aviation pilots like it a lot and that it has gained a lot of use far faster and wider than the safety community is comfortable with. Many legislators have been clamoring for replacing the aging instrument landing systems used by civil aviation with GPS based systems that could integrate tighter with on-board systems on modern airliners. But there is a big worry about reliability, especially the fact that a small jamming transmitter can very effectively disable GPS within its surrounding area. That sounds far-fetched, but is actually a very real risk.
The trucking industry has embraced GPS for fleet monitoring systems. A GPS receiver with a cell phone modem allows a trucking company to keep track of where its vehicles are moving. This is good for keeping customers informed about whether the load is moving on schedule, but it also allows a degree of supervision over the drivers that bugs many of them out of their skin. They like to think that when they are on a week-long cross-country trek with a load, they are lone warriors on the high range, masters of their own day-to-day life. But the GPS tracking device lets the company know exactly where they have been, and where and when they have been stopping. If they schedule an evening meal break in the parking lot of Gilley's dance hall on Saturday night, it is likely to result in some trouble. Much better for the driver if the device is somewhat unreliable, and fortunately, that can be arranged. Ads in the back of truckers' magazines offer a $30 device that plugs into the vehicle's cigarette lighter socket and transmits pure noise on the GPS radio frequencies. That will disable the GPS devices on the truck, and often all the other GPS devices in a half-mile radius around it. This turned out to be the cause of a lot of malfunctions in an experimental GPS instrument landing system that was being tested at Baltimnore-Washington International airport a couple of years ago.
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