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Random Quote: How did those footprints get on the ceiling in the head ?
[QOUTE] You read that, in plain english, and then claim that I made the "moronic claim that groundspeed doesnt matter in aviation:" I didnt say that. I said the airplane doesnt care about groundspeed to fly. Groundspeed is not a factor in the physics of flight. [/QOUTE]
The trademark of a strawman theory is to add irrelevant detail to a discussion.
To avoid this label explain EXACTLY WHAT THE FUCK how well an airplane flys has to do with the discussion about the accuracies of pitots and GPS.
yeah probably, if your autopilot is using a magnetic compass input. GPS doesnt know which compass direction your centerline is pointing toward, so it cant give you magnetic heading correction. It can tell you whether you are right or left of a line drawn directly from a starting point, or present position, to your destination point, but not how many degrees magnetic to steer to maintain it.
god, I almost wish I hadnt said that. somebody is sure to be upset about offending the GPS god.
stanley,...uh...
"To avoid this label explain EXACTLY WHAT THE #### how well an airplane flys has to do with the discussion about the accuracies of pitots and GPS."
you're kidding now, right? You know what? I cant communicate with you.
You dont get what I was trying to explain. You say you do, but you dont. I dont know what to tell you. I'm done trying to discuss it with you. And calling each other stupid isnt helping anything. So forget about it. I was wrong. You are right. You win. whatever was I thinking.
stanley,...uh...
"To avoid this label explain EXACTLY WHAT THE #### how well an airplane flys has to do with the discussion about the accuracies of pitots and GPS."
you're kidding now, right? You know what? I cant communicate with you.
You dont get what I was trying to explain. You say you do, but you dont. I dont know what to tell you. I'm done trying to discuss it with you. And calling each other stupid isnt helping anything. So forget about it. I was wrong. You are right. You win. whatever was I thinking.
You can't communicate because you are a troll using the classic strawman argument--and loosing.
yeah probably, if your autopilot is using a magnetic compass input. GPS doesnt know which compass direction your centerline is pointing toward, so it cant give you magnetic heading correction. It can tell you whether you are right or left of a line drawn directly from a starting point, or present position, to your destination point, but not how many degrees magnetic to steer to maintain it.
god, I almost wish I hadnt said that. somebody is sure to be upset about offending the GPS god.
You talk a big game and you contain half truths, but in sum you are wrong. Yes a GPS doesn't know which magnetic direction your bow is 'pointing' at a given instant but it damn for sure knows which direction (true or mag) your boat is moving. Yes if you are at anchor, the GPS won't be able to tell you which way you are pointing, but the second you start moving it can calculate your COURSE.
But it cannot tell you which compass heading to steer to maintain it. Only which side of it you are on.
Uh, no...forget that. I am wrong. you can prove it.
Unplug your compass input from your autopilot. Leave your GPS hooked up. since it 'darn sure' knows the correct course. Let the boat drive you home. Go ahead. Dont worry, your GPS will make the right decisions on which way to steer the boat. Really. And go really fast, cause GPS is more accurate the faster you go. In fact, take a nap. Just set a waypoint for the dock...but a couple feet off the pilings. So you'll have room to put the fenders out before tying up.
Get someone to film it. If its someone you like, have them do it from shore or another boat.
And then you can sell that compass and use the hole for another beer holder!! You dont need it. You got GPS.
I'm done with this. really. I just have to break myself from reading what you decide to vomit up next. Are you a GPS salesman?
But it cannot tell you which compass heading to steer to maintain it. Only which side of it you are on.
Uh, no...forget that. I am wrong. you can prove it.
Unplug your compass input from your autopilot. Leave your GPS hooked up. since it 'darn sure' knows the correct course. Let the boat drive you home. Go ahead. Dont worry, your GPS will make the right decisions on which way to steer the boat. Really. And go really fast, cause GPS is more accurate the faster you go. In fact, take a nap. Just set a waypoint for the dock...but a couple feet off the pilings. So you'll have room to put the fenders out before tying up.
Get someone to film it. If its someone you like, have them do it from shore or another boat.
And then you can sell that compass and use the hole for another beer holder!! You dont need it. You got GPS.
I'm done with this. really. I just have to break myself from reading what you decide to vomit up next. Are you a GPS salesman?
So you are claiming the little magnetic COURSE readout on my GPS is GUESSWORK or just a LIE? I don't think you have ever touched a GPS, much less understand how one works. And for damn sure you have never been behind a set of controls in an airplane.
"GPS is a little black box that uses voodoo magic, that on a good day can give you your position if stationary. All other information that it produces is unreliable and utterly useless in boating. How does it know how fast you are going? How does it know where you are headed? I don't know the answer to either, therefore GPS is voodoo magic."
I find this thread very interesting. I have just installed floscan and autopilot on my boat and have had questions about how it all works. I know my floscan is within 1% for 100 gals. gas and it works off the same principal as a pilot tube i think. I know my GPS will give me a track but not a heading. Its a shame its has to turn into a street fight. It got me thinking about things that i normally take for granted. I guess that's why we measure boats in hours and not miles
Hmmmmm....back to why would I want to be careful using a GPS unit to measure my MPG. It's really not that complicated (to me anyway) and may keep you from being "misled" on one of those sea trials.
Lets put the boat out in Lake Okeechobee and crank the engine up to 3500 RPM. The fuel burn reads 10 GPH and the GPS and speedometer (water speed indicator) both read 30 MPH. That's great I'm getting 3 MPG. Now lets drag the boat over to the east coast, head out Jupiter inlet into the gulf stream, crank the engine up to 3500 RPM and head north. The fuel burn reads 10 GPH and the speedometer reads 30 MPH but the darn GPS says 40 MPH (because the gulf stream is moving north at 10 MPH (I'm rounding up)). So now what? Am I getting 3 MPG or 4 MPG. Actually you are getting either depending on how you look at it. Relative to the ground you are getting 4 MPG but relative to the water you are still getting 3 MPG. I think the 3 MPG based on the "water speed indicator" is more consistent. Anyway, FWIW, the next time you demo a new boat and get your numbers from the GPS you might want to make a run in opposite directions and average the two. Even in the inter-coastal the water can be moving at a pretty good clip sometimes so check it both ways just to be sure.
I was beginning to think that whatever Stanley has, is somehow contagious. I knew he finally lost it about three of his posts back. Its sad, but thats the way evolution works. And I am really apologizing for all of my redundancy in trying to discuss this. If someone doesnt start to see how it ties together after a couple tries we should just move on. Please dont take his autopilot explanations, or much else he says, very seriously. He's damaged ,somehow. Its sad, and I would be surprised if his daddy lets him drive the boat by himself if he's reading this.
Hmmmmm....back to why would I want to be careful using a GPS unit to measure my MPG. It's really not that complicated (to me anyway) and may keep you from being "misled" on one of those sea trials.
Lets put the boat out in Lake Okeechobee and crank the engine up to 3500 RPM. The fuel burn reads 10 GPH and the GPS and speedometer (water speed indicator) both read 30 MPH. That's great I'm getting 3 MPG. Now lets drag the boat over to the east coast, head out Jupiter inlet into the gulf stream, crank the engine up to 3500 RPM and head north. The fuel burn reads 10 GPH and the speedometer reads 30 MPH but the darn GPS says 40 MPH (because the gulf stream is moving north at 10 MPH (I'm rounding up)). So now what? Am I getting 3 MPG or 4 MPG. Actually you are getting either depending on how you look at it. Relative to the ground you are getting 4 MPG but relative to the water you are still getting 3 MPG. I think the 3 MPG based on the "water speed indicator" is more consistent. Anyway, FWIW, the next time you demo a new boat and get your numbers from the GPS you might want to make a run in opposite directions and average the two. Even in the inter-coastal the water can be moving at a pretty good clip sometimes so check it both ways just to be sure.
I hope that helps.
For most people (reference the poll-you know what I am talking about) what matters at the end of the day is if they have enough gas to get home. They want to know how much gas it takes to get from Point A to Point B. This is much more useful than knowing their 'instantaneous' gas mileage like you are suggesting. Let's say you are fighting the above current, trying to make it home. your GPS # is now reading less then your 'wheelie', because you are now going over less bottom, but more actual water. Which number would you use to figure out how much fuel you are going to use to get home?
I was beginning to think that whatever Stanley has, is somehow contagious. I knew he finally lost it about three of his posts back. Its sad, but thats the way evolution works. And I am really apologizing for all of my redundancy in trying to discuss this. If someone doesnt start to see how it ties together after a couple tries we should just move on. Please dont take his autopilot explanations, or much else he says, very seriously. He's damaged ,somehow. Its sad, and I would be surprised if his daddy lets him drive the boat by himself if he's reading this.
Tell me, you don't understand much of anything. I like you claim as being a pilot. I'll bet your uncle let you sit in the left seat of a 172 once, and now you tell everyone you can fly. Ha.
You have no idea how an actual GPS works, and have demonstrated this with your repeated posts.
Time and Time again your arguements demonstrate the classic strawman theory, you pick and pluck facts to your liking and ignore other just as important facts. You, sir, are a classic Troll, and anyone who listens to you should do so at their own risk.
Gringo Would a GPS accurately measure MPG in a car traveling in the mountains?
yeah, because its mechanically coupled to the fixed earths surface through the drivetrain. It would'nt be straight line point to point in the horizontal plane distance, "as the crow flies", but it would tell you how many miles of road your wheels rolled over.
Stanley, I feel sorry for you. Really, I do. How many times did you flunk Reading Comprehension before you tried Debate for part of a semester? I dont need to repudiate your ridiculous posts...they are the best argument there could be against your brand of 'logic'.
Why do you do this to yourself? You misquote things written down, which people can easily scroll up and read. You keep harping on about my pilots license, when its easily verifiable. You cant prove your claims that I dont have one , whereas I can prove that I do. How can you win that argument? You claim I have never touched a GPS, when I spent 20 years interfacing tracking and navigation systems to them. Do you really think anyone believes I dont know anything about GPS? You are shooting yourself in both feet.
At least you apparantly learned something about the Straw Man bit. Or some of it. Its not a "theory" its a debating ploy.
The arguer makes up a proposition never offered by the opponent (usually weaker than the true proposition) and then attacks it as if his opponent had offered that proposition. Why dont you look back through your posts and figure out who is trying to use this debating ploy here. Guess what, sunshine....it aint me.
Look...why dont you expain Differential GPS to us all, in your own words, and why it came about, and who started using it first? I will let you handle that totally. Ok? Lets see if you can do it. Some people might be interested in how it works.
and you can show me up once and for all, oh great GPS god.
Peace.
You claim I have never touched a GPS, when I spent 20 years interfacing tracking and navigation systems to them. Do you really think anyone believes I dont know anything about GPS?
In fact you have demonstrated very little knowledge of how a GPS operates. You haven't countered a single argument I have made, instead you resort to name calling and irrelevent claims.
If you do have a pilot's liscense I hope I never have to be in the same portion of the sky as you, or to be more appropriate below your flight path because you'll have to make a crash landing soon because you apparently use indicated airspeed to make your fuel calculations.
Oh, and I'm not going to do your research for you......you've got a lot to learn about GPS and I suggest that instead of wondering at it's voodoo magic , you hit the books.
Hmmmmm....back to why would I want to be careful using a GPS unit to measure my MPG. It's really not that complicated (to me anyway) and may keep you from being "misled" on one of those sea trials.
Lets put the boat out in Lake Okeechobee and crank the engine up to 3500 RPM. The fuel burn reads 10 GPH and the GPS and speedometer (water speed indicator) both read 30 MPH. That's great I'm getting 3 MPG. Now lets drag the boat over to the east coast, head out Jupiter inlet into the gulf stream, crank the engine up to 3500 RPM and head north. The fuel burn reads 10 GPH and the speedometer reads 30 MPH but the darn GPS says 40 MPH (because the gulf stream is moving north at 10 MPH (I'm rounding up)). So now what? Am I getting 3 MPG or 4 MPG. Actually you are getting either depending on how you look at it. Relative to the ground you are getting 4 MPG but relative to the water you are still getting 3 MPG. I think the 3 MPG based on the "water speed indicator" is more consistent. Anyway, FWIW, the next time you demo a new boat and get your numbers from the GPS you might want to make a run in opposite directions and average the two. Even in the inter-coastal the water can be moving at a pretty good clip sometimes so check it both ways just to be sure.
I hope that helps.
For most people (reference the poll-you know what I am talking about) what matters at the end of the day is if they have enough gas to get home. They want to know how much gas it takes to get from Point A to Point B. This is much more useful than knowing their 'instantaneous' gas mileage like you are suggesting. Let's say you are fighting the above current, trying to make it home. your GPS # is now reading less then your 'wheelie', because you are now going over less bottom, but more actual water. Which number would you use to figure out how much fuel you are going to use to get home?
FWIW, I did say that both answers are correct depending on your point of view. It's just a matter of what you want to know. Your approach will tell you how much gas it takes to get home under current conditions and yes that is VERY useful information. The other information will tell you how efficiently your boat moves "through" the water and that's good information to help you decide which boat gets the best gas mileage. The little "wheelie" (water speed indicator) may not be necessary to survive in a boat (I don't have one on my boat) but you aren't going to last too long in an airplane with just a GPS and no air speed indicator because they report "different" information.
The little "wheelie" (water speed indicator) may not be necessary to survive in a boat (I don't have one on my boat) but you aren't going to last too long in an airplane with just a GPS and no air speed indicator because they report "different" information.
This is indeed true, but the current discussion is about fuel economy, and in airplanes the kind of fuel economy that matters is having enough fuel to get to your destination. To know this you need to know groundspeed. Period. While you don't need a GPS to figure groundspeed in an airplane, it makes the process about 100% easier and is signifigantly more accurate (although I'm sure gringo will argue that point).
Re: Connecting Yamaha Gauges to GPS 
