hey does anyone no a good way to take ya gear on a push bike??? cus im olny 15 and no licience

Nickoff said...

hey does anyone no a good way to take ya gear on a push bike??? cus im olny 15 and no licience

Is this on the right topic? Didn't you mean to put it on the motorbike post?

And yes there is a way, carver surf racks also make them for push bikes. carverracks.com

the oceans are international so using the same measurements all over the world makes sense same as you pass on the right on the water. also speed was calculated by throwing a rope over the back and counting the knots that go by in a certain time frame.

AND ..... we all understand how nice 25 knots is !!!!



Fizy - Gold Coast OZ

A knot (nautical mile) has its origins with lattitude and longitude (co-ordinates on the planet). 1 degree of lattitude equals 60 nautical miles. Each degree contains 60 minutes, and each minute is one nautical mile. So a ship travelling 20 knots (nautical miles per hour) will cross one degree of lattitude every 3hrs if heading due north/south.

Ships and aircraft all use knots as their base measurment of velocity due to travelling across the worlds surface, so most things to do with aviation and shipping are in knots, including aviation wind forecasts etc

It just depends what your used to. To do the conversion from knots to km/h, just times by 2 and subtract a tenth of the answer. That will give you a close estimate good enough for government work. (ie 15kts = 27km/hr)

For the guys who stated it was knots tied in rope to measure speed, I think they may be getting confused with the knots tied in rope to measure depth in the old days. Those boys would have needed some serious long rope to measure even a few knots !! Surely it would have slown them down even more !

Also - one minute of lattitude is always 1 nm wherever you are in the world. The distance of one minute of longitude canges depending on where you are in the world because the meridians all converge to the poles. Except at the equator. One minute of longitude also is 1nm there !!

Hope your not all too confused.

Back in the really early days of sailing Square & Gaff Rigs AAAARGH!!!!
They had a poopdeck load of rope that had a knot every mile.
They would tie a drogue (go google it!!)
to the end of said rope and chuck it off the stern.
The time it took for each knot to go over would tell them their average
speed +or- 10%.
So 1 knot=1&1/10th mile.
AAAARGH!!! the good old days +or- minus 10%.
Excerpts from the Ancient Mariner.

And all that has what to do with wind?????????????
If you thought you were confused now,
try working out what the northern hemishere trash
refer to as Beaufort!!!!!!!!!
For me its 1. not worth it
2. 14meter
3. 11meter
4. 7meter
5. Too bludy windy!!!

its not out dated your just lazy! if people like you own boats and use metric measurements well lets say i hope you have insurance ha ha .

manicskier said...

But Choady, a nautical mile for a plane travelling at 30000 feet is further than a nautical mile for boat at sea level, isn't it... the earth is round yeah??? doesn't it just apply to the water, ie 'nautical'??

A nautical mile is still a nautical mile whether at 30,000ft or sea level. Perhaps your getting confused with indicated airspeed and True airspeed?

Even though the earth is round, its a massive sphere (not a perfect one), thats over 21,600nm round at the equator. At 30,000ft, your only about 9km, or 5nm above sea level, so this extra height is totally negligible when it comes to calculating the distance between two points at sea level or 30,000ft. A nautical mile is a nautical mile regardless of the height. But, you are correct in saying the distance between two points on the earth is slightly longer at 30,000ft, but its so small it makes no real difference.

So it certainly doesn't just apply to the water, it just originated with sea travel. Aviation use exactly the same method of nav that ships do. Whether boat or aeroplane, the shortest distance beween two points on the earths surface is a great circle, not a straight line due to curvature of the earth. This distance is measured in NM, and speed used is nautical miles per hour (knots).

Dawn Patrol said...

The nautical mile is 1852m and is used for scientfic purposes the define distance with precision is a distance of 1852m. And has NO GENERAL USE IN NAVIGATION.

The statement that a nautical mile has no general use in Navigation is absurd and naive.

To navigate accurately, you need an accurate direction, velocity, and distance or time. The velocity and distance are knots and nm respectively. As I mentioned previously, 1 nm is one minute of lattitude arc along a meridian. The NM for all intensive purposes is a sea mile too. The distance is exactly the same for both. Using a sextant, very accurate measurements of lattitude can be obtained from sun/star angles. This therefore directly equates to degrees and minutes of arc which are nm. All aircraft and ships use nm and knots to navigate by.

Unfortunately Sebol, who says "knots are useless outdated mesurements and we would be all much better off using km - Come on cave men, join the modern boat ."

We would have to devise a new way to pin point co-ordinates on the earths surface and travel between them !! I think Sebol - you need to be more open minded how and why things are the way they are, rather than have the whole world change to fit in with the speed your car moves at !!

This thread is getting like the Telstra commercial ' Why did they build the great wall of China dad? "

"Emporer Nasi Goreng build it to keep the rabbits out - Son"

That 15yr old looking for a way to carry gear on his bike will soon be at school discussing the finer points of nav with his mates saying you got to throw rope to measure wind speed, and that the nm has no use in navigation .

You guys seem bored. You should have come to kitestock.