It's so quiet that animals sometimes don't hear you. I hit a cat today while in stealth doing around 40 mph.
The spaceship noise maker (VPNS) in the 2012 makes it harder to creep up on wild animals for a closer picture. But at 40 mph, an animal would normally hear your tire noise, unless a lot of noise pollution interferes.
I was doing 15MPH in my '12 with the spaceship noise maker the other day. A cat was stretching on the street and refused to get out of the way. I had to honk. Maybe they do not hear in that frequency.
It was Natural Selection. Trust me.....you're not as quiet as you think you are when you're doing 40. Tires make a lot of noise, and a young healthy feline is pretty hard to hit unless it's dumb, deaf, or distracted. Don't be prejudiced. Carrion eaters aren't as 'pretty' as kitty cats, but they have to eat too.
The cat could hear you. They can hear from about 45Hz to 65KHz. The inverter switching frequency will output serious harmonics at that frequency. The "whine" that some people can hear is in the 24KHz range, like old TV's and so on. And that is an even smaller amplitude. Not to mention cats have great visual senses as well. The cat was probably accustomed to getting away with it. Cars slow down for it all the time probably. Just like the deer that live on my property. Essentially large pooping pets. You can walk right up to them talking to them, open the garage door, use the garden hose, talk on the phone whatever. They don't care. Find a deer that doesn't live in the city and a broken twig will send it running. Not your fault or the Prius'. Natural selection.
Look at the bright side I guess. Better a cat rather than a person. (sorry... I'm not a big cat person) Stealth mode is one of my favorite features of the hybrid / pure electric cars. I have already inadvertently startled some people in parking lots and near my neighborhood that didn't realize I was driving near. hehe
Yeah, I've been frustrated by people in parking lots when I'm coming up from behind them. I wonder why aren't they getting out of the way, then I remember. "Oh, yeah ..."
Honestly, the Prius isn't much quieter at that speed than a conventional car. Walking around our neighborhood, it's the tires on the pavement that I hear coming from the passing cars, not their engines. I feel your sorrow.
2012 Prius Vehicle Proximity Notification System (VPNS) - Video This is meant to alert pedestrians, especially the blind, that an electric or electric-hybrid car is moving nearby. In the future, it may also apply to quiet cars with traditional engines.
At 40 mile per, a hybrid is making the same road and wind noise as most other vehicles. Darwinism at work.
