Drifting question, how far after high speed pass?

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Hi all,

Last question, thanks for help!

On a speed pass, when its directly over head, 10 feet off the ground, let go of the controls, how far does it take to stop to a hover in GPS mode?

Mine seems like it goes about 10-15 feet before it stops to a hover. Thats full speed, left off controls overhead. Does that sound normal?

Thanks again.
 
Sounds normal to me, its momentum and i'm sure it's somewhat accounted for in the software to allow smoother camera moves. My dad, being a new pilot, was not aware of this behavior and allowed the phantom to hit a lightpole. He now practices braking maneuvers to counteract the momentum.
 
Yep, that's about right. And just wait to see how long it takes to recover attitude and hover from a 90 degree full tilt run in manual mode!
 
ElGuano said:
Yep, that's about right. And just wait to see how long it takes to recover attitude and hover from a 90 degree full tilt run in manual mode!

Does your definition of recovery include interaction with foreign objects? :cool:
 
You need to remember GPS accuracy is to within 15 meters with all but the newest GPS systems. The newest GPS systems are capable of accuracy's of 1 meter but only if they are on a Satellite that is currently overhead and capable
 
FASTFJR said:
You need to remember GPS accuracy is to within 15 meters with all but the newest GPS systems. The newest GPS systems are capable of accuracy's of 1 meter but only if they are on a Satellite that is currently overhead and capable

Actually almost all modern consumer GPS electronics from the last decade have 1m accuracy. What you're probably referring to is Selective Availability, in which the us govt encrypted the least significant bits of the positioning data. They disabled that years ago, which is why we have highly accurate consumer nav options now.

It's a transmission precision enhancement, not a hardware or satellite change.
 
Answered this once (10-15 feet sounds right for me, too) and decided you wanted to know about manual mode. Then couldn't tell which we were talking about. Will repost this just in case it might help. This was an answer to a question about flying in cold weather but it shows a quick stop. I probably touched reverse just a tad at the end but it was not going to go very far.

http://www.youtube.com/watch?v=EDrH8_wnL0Y
 
ElGuano said:
FASTFJR said:
You need to remember GPS accuracy is to within 15 meters with all but the newest GPS systems. The newest GPS systems are capable of accuracy's of 1 meter but only if they are on a Satellite that is currently overhead and capable

Actually almost all modern consumer GPS electronics from the last decade have 1m accuracy. What you're probably referring to is Selective Availability, in which the us govt encrypted the least significant bits of the positioning data. They disabled that years ago, which is why we have highly accurate consumer nav options now.

It's a transmission precision enhancement, not a hardware or satellite change.

I'd like to see the stats on it :roll: I've owned 3 boats and 3 Garmin Plotters over the last 12 years. My latest is a Boston Whaler with a $4000.00 Garmin Plotter / Sounder. I'm lucky if I see 10-15ft…………3ft is hard to believe for consumer
 
FASTFJR said:
ElGuano said:
FASTFJR said:
You need to remember GPS accuracy is to within 15 meters with all but the newest GPS systems. The newest GPS systems are capable of accuracy's of 1 meter but only if they are on a Satellite that is currently overhead and capable

Actually almost all modern consumer GPS electronics from the last decade have 1m accuracy. What you're probably referring to is Selective Availability, in which the us govt encrypted the least significant bits of the positioning data. They disabled that years ago, which is why we have highly accurate consumer nav options now.

I'd like to see the stats on it :roll: I've owned 3 boats and 3 Garmin Plotters over the last 12 years. My latest is a Boston Whaler with a $4000.00 Garmin Plotter / Sounder. I'm lucky if I see 10-15ft…………3ft is hard to believe for consumer

1m is very very unlikely without DGPS. The removal of Selective Availability in 2000 improved consumer GPS to less than 20m (not 1m). Further improvements like WAAS/EGNOS, more L4 capable satellites, better algorithms, etc. brought this down to less than 5 - 10m. But to get to 1m accuracy levels you really need DGPS to cancel out atmospheric drift. That's a minimum of $1,000 (http://swift-nav.com/piksi.html) and more typically $10,000 but you get close to 1cm accuracy which is pretty amazing.

For the Phantom, it's important to remember that unless you are taking off, navigating and landing in a very specific confined space, you really only care about relative accuracy. That means that even if your GPS is off by 20ft in one direction due to atmospheric conditions, as long it stays off by the same 20ft for your entire flight, you don't really care.

BTW, as for next generation GPS satellites broadcasting L5 signals, there are only 4 in orbit so far.
 

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