And they don’t have a clue about north-south-east-west.
Do gas stations/C-stores even sell folding paper maps anymore? They used to be free, but now I’m really reaching back into the bronze age.
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I just started using the free version of Strava this year- more because people always ask how far/ fast I go when I paddle and I’ve never had a clue what the real answer was. The average speed stays pretty consistent around 3.4 to 3.7 mph. I don’t think it’s as good at capturing max speeds. On a recent trip it said I hit 12 mph. I don’t think I’ve ever gone that fast. This one is more typical
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depends on wind and current you can hit 12 mph
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I’m a real slug. On my trip this Summer I averaged under 3 mi/h over 225.7 miles. Somewhere between 2.2 and 2.7 to be truthful. Average daily mileage was a hair over 15 miles.
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I think it’s hard to interpret my own GPS data much less someone else’s. Recently I’ve been enjoying long slow cruises on the St Joseph river watching fish and looking at the bottom since the water and current are low and probably averaging a little over 3 mph paddling a fast boat at a slow pace. I was pondering why the same pace was harder to maintain on the smaller Paw Paw River even with less current. Then I realized that on the St Joe I accelerate the boat to cruising speed just once and then go for miles while on the Paw Paw you have to slow or stop the boat constantly to get around or through fallen trees so you have to accelerate the boat hundreds of times on a 10 mile paddle and don’t spend much time just cruising. So for me a “weenie” pace on the St Joe could be same as an “I’m getting rained on” pace on the Paw Paw.
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if you enjoyed it nothing else matters.
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Loaded kayaks on a camping trip will have lower speed. Does anybody care about that unless the trip is to set a speed record in the first place?
Pacing to make the distance in something resembling comfort, to see what you went there to see, and enough margin to enjoy meals and time at camp, plus allowance for bad weather—the whole package matters more than sheer average speed.
Keep on doing what makes you happy and keeps you reasonably safe.
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I’ve been avoiding this up till now but time to chime in. There is a good description of how GPS works in wiki, and having had a career in programming I can at least pretend that I understand it.
There is a fundamental limitation to GPS in that the position from any individual reading set can be off by many meters. It is up to the software on your device to deal with that by smoothing or averaging a series of readings to tell where you are, and from those points plus time stamps with atomic clock accuracy to say how fast you are going.
The smoothing algorithm cannot be optimized for everything that GPS is used for. For example, a hiker might step north one second, east a second later, south, then west. A jet fighter OTOH goes in pretty much a straight line. An algorithm optimized for the jet fighter might simply round off the hiker’s steps as positioning errors and show that the fighter didn’t move.
Cell phones have used GPS for years, among other things to help pass off signal from one cell tower to the next. It is on all the time. When the police find out where the perp has been on TV shows (or Google tells you where were last month) it is because the phone keeps a record these GPS coordinates. GPS apps can use this record even if they were not running at the time of recording.
I’ve used a free app on my android phone for years called Geo Tracker. Over the years many other apps have showed up with the same name, this one is from Bogdanovich. The app can dump positioning information into an XML (text) file called a KML so I can open it in google earth and see my track. I can also open it in Notepad and see the actual data recorded by the app. Here is an example:
gx:coord-81.63160854 46.05034613 144.83</gx:coord>
2023-06-23T16:35:34Z
gx:coord-81.63145847 46.05036041 144.04</gx:coord>
2023-06-23T16:35:40Z
gx:coord-81.63131587 46.05036352 143.11</gx:coord>
2023-06-23T16:35:45Z
gx:coord-81.63116145 46.050364 143.94</gx:coord>
2023-06-23T16:35:51Z
The coordinates are longitude, latitude and altitude. The when /when entries show up in my browser as time stamps. The app or the software on my phone’s operating system is smoothing thousands of readings to show where I am every 5 or 6 seconds. If you reverse the latitude and longitude and type that in to Google Earth it shows the location of each of these XML entries.
To see an example of error, look at the altitudes. I was paddling on flat water but the altitude bounces up and down by a meter. Earth also does some rounding, but spikes of 8 meters still show up if I look at the altitude and speed graph for this trip. Presumably the locations are off by the same order of magnitude; the only thing that is accurate is the time.
Imagine what this inaccuracy does to instantaneous speed measurements. If I select my path on Earth it shows the course and speed calculated from the closest xml entries. One part of my track where I was paddling at constant speed shows successive speeds of 1.79, 2.85, and 1.91 meters per second. This inaccuracy is inherent in GPS regardless of the device you are using, although any device for a specific use like hiking or driving a car could have smoothing algorithms optimized for that use.
In short I would trust total distance and average speed readings from GPS as pretty darned accurate, but I would not trust instantaneous or max speed at all.
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The only time I care about speed is when I paddling with a group. I don’t want to hinder a group. I also care when group members are leaving behind slower paddlers when the idea is to paddle as a “group.”
Paddling solo, I am just doing my thing and following along with my natural rhythm for that paddle. Couple of times got too engaged/enamored with playing in surf to monitor seriously the incoming line of storm clouds, thunder and lightening, until it was almost on top. Then it was a mad hustle for safety.
Surprising, the only times I am sort of aware of my speed is when I am kayak fishing. My onboard GPS/fishfinder indicates that i normally paddle between 3-3.5 miles as my “natural” speed (meaning that I am not pushing it) with my Scupper Pro.
sing
Agree, but the key word here is: ‘instantaneous’ (eg: 1 reading)
If my push myself for a while, and checking the gps (speed) for several readings (updates), and it remains the same (within a few tenths), I find it reliable.
(btw - a difference between the Garmin 78 and 86 is that the 78 would ‘grab’ a Max Speed as the first time it appears (speed). The 86 ‘waits a while’ (several readings) before grabbing it as a Max)
OK I’ll go back to a long rope with knots for instantaneous and max speed.
When I see a GPS speed posted my engineering background reminds me that the first questions you’d ask an engineer when they show data is “Show me your test procedure and test/test variability”. Even when I try to take GPS data under semi-controlled conditions I know it’s sloppy and full of uncontrolled variables (my route, my power output, wind, current, etc)… In my mind all we ever see are anecdotal data points floating around in space.
test GPS in in a car with consistent speed set low and high speed.
I’ve been told that GPS accuracy decreases as latitude increases, esp above 45 degrees.
Is that true?
(For reference, BWCA is about 48 deg N)
@system, lying about actual paddling or bicycling speeds doesn’t make sense. There’s nothing to gain, and everthing to lose if you get exposed, and even if anyone believes the lie, most of us are anonymous to other members on the forum, so what is there to gain. Several recent members posted racing times, and those speed were corroborated by members who were present, actually competed or saw posted results. You would have to be fairly pathetic to lie to stangers who would never meet you. That personity trait would manifest itself in due course.
@slushpaddler, pointed out that most member of the forum could care less about speed. Many forum members will point out that “there are more important things than speed.” WW speed might be of value if you run slolum courses, but much depends on water flow. A surfer might benefit from knowing peak speeds over time for personal reasons.
Measuring progress in physicsal conditioning, efficiency, assessing the speed of a boat or effectiveness of a paddle’s square inch surface area, length, or design comparing a Greenland to a Euro or a Wing is measured through speed. How do you measure speed. I’m more suspect of a paddler who claims a boat or paddle or technique or their state of conditioning is more effective, based on mere “perception”.
Police use radar, because it’s convenient. Radar accuarcy is accepted only because the devices are calibrated based on court accepted standards and regular certification. Police officers are trained and certified so they understand the limitations of radar. The most important parameter is to exclude speeders under a minimum limit to make error irrelevant. Someone speeding one mph over the limit can be thrown out, but 10 to 15 mph is harder to dismiss. Back in the 70s, VASCAR was introduced. As with radar,officers were trained and devices checked and certified. It simply calculated time over distance. I suspect it’s still used, because I see pre-measured lines on highways that can be fed into the device.
Another way to messure is with a calibrated wheel. I have a bike speedometer that relies on front wheel circumference. A difference of 5 psi in the front tire pressure will change overall distance by a few tenth of a mile over 40.6 miles as measured on a marked trail. Some of the arguments I read above are baseless conjecture. It’s easy to dismiss a method as inaccurate, but if you had a clue, you’d simply point out the rate of error based on mathmatical reality. For example, if the trail is factually 40.6 miles to the inch, cutting corners or going wide will change the actual distance traveled, but by how much, .1 miles, .5, .6, or maybe 1 mile. Well how significant is the error. Do the math:
41.0 miles in 3 hrs = 13.66 mph
40.6 miles in 3 hrs = 13.53 mph
40.0 miles in 3 hrs = 13.30 mph
39.0 miles in 3 hrs = 13.00 mph
So a 2 mile error in distance comes down to .66 mile error in overall speed or a difference of 13.0 or 13.66 mph. Is it worth calling a cyclist a LIAR for claiming to have covered 40.6 miles in 3 hours at an avg speed of 13.53 mph.
So what would you say if that person traveled that 40.6 miles in 2 hrs 10 minutes and claimed an avg speed of 17.42 mph. Somebody on the forum would protest that it’s not possible to estimate to the 100th of a mile or within .02 of an mph. What did it tell the cyclist: how physical conditioning improved over the season, possibly how better technique helped. Did different gearing improve stats.
So what do you think would be revealed if the rider switched to a road bike, changed air pressure or tires, changed from 21 speeds to 27 speed derailleur. Oh, I doesnt matter, speed isn’t everything - then you are on the wrong thread. Your opinion is of limited value -YOU DON’T CARE.
So how about cutting corners. Well won’t a person follow a similar track oit of habit??? If not how much can it matter. Look at a map and get your compass and a scale then measure a few curves over a given distance and calculate the error rate in 10 miles if an inside track or outside track was followed every time a corner was taken. I will speak for myself - I followed the tire track on the proper “right side” of the trail, because the center of the trail had a raised grass covered hump that is a pain to jump back and forth over (but maybe I’d LIE to impress the reader? How pathetic).
The obvious key is that its easy to measure air pressure, stay on course, compare actual distances and record only moving times. Who benefits from cheating, and why record a cheating score for public disclosure, then actual score for your own benefit. Be real!
Frankly, thinking such thoughts makes me suspect. Personally, I’m inclide to believe a person’s claims, rather that dismiss them off hand. Look at the claimed distance, the time of traveling, and the reported avg, then challenge discrepancies. If you don’t care about speed, why does it even matter.
I covered relative GPS accuracy in other threads and will not waste that effort again.
For the past two years. I’ve covered the same course under different conditions, demonstrated efforts to follow straight course tracks that overlapped in both directions, as well as from trip to trip. I also intentionally allowed the wind to blow the boat at will. The results are remarkable. Still the attitude of many readers is that the results are spurious. How do you measure physical conditioning, which boat is faster, which paddle is better, which technique is more efficient.
It comes down to comparing different methods. Compare times over a set distance and measure time. Compare that to a GPS. Check consistency over multiple trips. It’s one thing to suggest cutting a turn wide or taking a more direct course creates error, but another thing to test for it, by repeating the trip by taking a wider or more direct route. Or do what many do, just guess, then tell anyone who calculates speed that its insignificant, but be careful calling them a liar, or even delusional. That could be construed as self- “definition of character” as Archy Bunker described.
I tend to save GPS tracks so when somebody has a question I can send them a JPEG of the track and tell them what the distance is and show where the launch is and sometimes show where a good place to stop for lunch or a break is. If they want to add or subtract exploring various coves or creeks, they can estimate how this might affect the distance.
Our Club uses 3 knots (3.45 mph) as an average trip speed. Less than that is considered scenic allowing for sightseeing and picture taking. Over that is considered a performance paddle where the intent is to cover more distance over time.
I use my own speed to estimate when I’ll arrive at a specific point or judge how hard I’m working. I don’t obsess over it.
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I am not sure all of it is a lie, people just can’t understand speed when on the water. It is complicated by current, structure, and other boaters.
Of course some people do lie, almost as much as they lie about sex, because that is all some people have to hold on to.
I won 9 state Championships and know that over all of those races I averaged a little over 6 miles an hour. With a 200 cubic feet per second current that means about 7 downstream and 5 upstream. Same kind of thing for higher current rates also.
Marathon races are not about top speed and I know I can go faster but the energy needed and the lactic acid burn make it the enemy of a long paddle.
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The US and chinese satellite orbits are tilted so each satellite reaches 55 degrees latitude. Galileo’s is 56. For sure the speed and accuracy is best if you are surrounded by satellites, so the farther you go from the equator the worse the accuracy will get because more and more of the satellites will be off in the same direction (south). I don’t know about any 45 degree figure.
OTOH my phone https://www.gsmarena.com/samsung_galaxy_s20-10081.php uses all four systems including GLONASS, the Russian one. Not surprisingly given Russia’s geography they work better up north; their satellites’ orbital inclination is 64 degrees.
And I’ve never heard of people in Great Britain or Norway complaining about GPS. Their capitols are well north of BWCA.
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Interesting. Many thanks.
Saying you went 6 miles an hour isn’t the same, just like claiming you have sex 4 times a night. A lie means it didnt happen. If paddling 6 miles an hour for 10 miles happened, it only matters to me if the person can explain how to me how I accomplish it. Then I will decide whether its possible. If I believe the feat is only possible by a superhuman and that person is not a super human . . . At least the liar has a comforting fantasy to salve their misery. Goid for them, but I need more.
Dont use a GPS. Make it up as you go along. If it feels like you’re going faster, just day its faster. Or take comfort in saying, “Speed isn’t everything!” Is speed over ground faster if you’re going with the earth’s rotation or against it, and does it matter.