How Fast Are You REALLY Going.

[The Toad in the Hole]

I also use a hand held GPS - its a fairly old model Garmin originally designed for yachtsmen but it is extremely accurate - often down to a couple of metres. Before buying the boat, (and before I retired) I used it to time the speed of trains - most of our locomotives did not have accurate speed measurement devices.

 

 

 

Don't trust the given accuracy of a handheld gps. And definitely don't trust the vertical height, that can be tens of metres out. If it's an old 'un, it won't have EGNOS capability (confusingly called WAAS in the GPS menus - an American thing), which will gee up the accuracy by using a differential signal. With an older handheld you'd strugge to get +/- 7-10metres, which means speed calculations over short distances (like going into a lock) won't be remotely accurate.

 

Accuracy isn't much of an issue for narrowboats, but the height is important for mountain navigation, which is why most handhelds have a barometric altimeter - but then that needs constant recalibration to account for weather/airpressure on the day!

 

Look for a GPS with the SiRF chipset - it's much better in towns etc as it can be seen more easily in "urban canyons"

[Ernie]

1) Even though I think I enter locks at a crawl, to avoid excess smoke when stopping, I was consistently driving into locks (through a single gate) at at least 2.5mph. Where this exceeded 3mph, although stopping was easily possible, our elderly engine made more smoke than I would like. I'm sure many modern boats with powerful smoke free engines enter locks at around 3mph.

Ever had a morse cable or linkage brake on you, I have, not pleasant.

Can you imagine steaming into a lock at 2.5 MPH and all of a sudden, no reverse – wouldn’t want it to happen to me…..

[alan_fincher]

Ever had a morse cable or linkage brake on you, I have, not pleasant.

Can you imagine steaming into a lock at 2.5 MPH and all of a sudden, no reverse – wouldn’t want it to happen to me…..

A very valid point.

 

We have not yet had any problems like that with mechanical failure on this boat, but large items of clothing around the prop have caused us to not stop as quickly as we would have liked on maybe 2 occasions last year.

 

In my defence, at this time of year, the Marsworth locks have large amounts of excess water swamping the pounds, which run in from an inflow just below one of the bottom gates. If you don't go in at a fair speed, this takes your bow, and pushes you into the unopened gate.

 

I'm inclined towards the explanation just given that it isn't 2.5 or 3.0 mph really - it certainly doesn't feel like it, and anyway the action of slipping through the (just over) 7 feet gap does take a lot of that speed off, even without reversing.

[NB Alnwick]

What speed where you doing there then? Very impressive looking - must be getting on for 7 mph at least.

 

We have rarely exceeded 7.2 mph on static water - that was the sustained maximum that we achieved on the Gloucester & Sharpness Canal last year. If you look at the picture (repeated below) the hull is beginning to sink into the trough created by its own bow wave! As speed increases, so the trough becomes deeper and requires considerably more horses to climb out of it. We have the power to achieve another two or three miles an hour but this would need a bigger prop than our current 24" square! Having said all that we once covered 22 miles from Sharpness to Portishead in two hours dead - an average speed of 11 mph but we did have a considerable tide flow advantage.

 

Lighter boats with a shallower draught and perhaps a longer hull may be able to go faster and specially designed high speed hulls with powerful engines can 'plane' above the trough (rather than sitting down in it) but I doubt if there are any narrow boats capable of aquaplaning!

 

 

Ever had a morse cable or linkage brake on you, I have, not pleasant.

Can you imagine steaming into a lock at 2.5 MPH and all of a sudden, no reverse – wouldn’t want it to happen to me…..

 

I wouldn't want to trust any sort of cable to change gear - I very much doubt if you could disengage a Kelvin gearbox with a cable unless it was of mammoth proportions.

[Naughty Cal]

Look at that a narrowboat that moves.

[bottle]

Look at that a narrowboat that moves.

 

and the sound, is to die for, much better than those high revving, high powered engines that some boats have.

Edited February 27, 2009 by bottle

[Naughty Cal]

You may bring be around to narrowboats yet!

[Neil TNC]

You may bring be around to narrowboats yet!

 

How about 15mph on the GPS coming up through London on a Flood tide, all the way from LW at Wallet Spitway to Brentford?

(average speed 8.5 mph)

Made the trip boats think twice about ambling off in front of a narrowboat.

Mind you this was one day off the highest spring tide of the year (barrier used the day before.)

[Naughty Cal]

How about 15mph on the GPS coming up through London on a Flood tide, all the way from LW at Wallet Spitway to Brentford?

(average speed 8.5 mph)

Made the trip boats think twice about ambling off in front of a narrowboat.

Mind you this was one day off the highest spring tide of the year (barrier used the day before.)

 

Dont know. Has to be capable of speed under its own power to interest me im afraid.

[NB Alnwick]

How about 15mph on the GPS coming up through London on a Flood tide, all the way from LW at Wallet Spitway to Brentford?

(average speed 8.5 mph)

Made the trip boats think twice about ambling off in front of a narrowboat.

Mind you this was one day off the highest spring tide of the year (barrier used the day before.)

 

Our fast trip from Sharpness to Portishead was heavily influenced by our pilot who overheard the 'first mate' on a launch beside us say something like "I hope they don't let that old barge out in front of us - they are so slow" - outside the lock gates, the pilot said "OK, open her up and let's see what she can do" at that point the tide was still coming in and the other boats were barely making headway - we made about 5 mph flat out but within half an hour or so we were well out in the channel, we had the tide in our favour and most of the other boats were a long way behind - you can't even see them (except as specs in the distance) in the photo below . . .

 

[alan_fincher]

You may bring be around to narrowboats yet!

Come on narrowboat owners - lets not try too hard, shall we!

 

 

Sorry! - Uncalled for!

[mykaskin]

Does the GPS work in the tunnel, or is this a case of an average speed based on time in, and time out ?

 

Mine displays a line between each received point with the average speed between them. So we get a straight line between entering the tunnel, and exiting (it takes a few seconds to lock back on again, but it's not far off) and will display the average speed it takes. However with the Blisworth timings I used a stop watch, and the published tunnel distance.

 

Talking of open water speed, our max speed in Kismet was 12 mph, but this was running with the tide past Reeds Island towards the bottom of a spring. She will do 6.5 mph in still water - we leave most narrowboats for dead. In fact last year we were running flatout trying to catch a locking at Cromwell and we were catching up with another narrowboat. He had the same engine as ours, and was also running flatout (also trying to make the lock), so it isn't all down to the engine.

 

When crossing for the Ribble link, even though we were in the last of three lockings, along with 1 boat from the first lock with extra propulsion and cheating (he was a local and knew the shortcuts!) we were the only one to make the link in time. Video here:

 

Re:Stopping in locks - thats why God invented ropes and bollards - however the devil BW try to make this difficult.

 

Cheers,

 

Mike

[Naughty Cal]

Come on narrowboat owners - lets not try too hard, shall we!

 

 

Sorry! - Uncalled for!

 

Wouldnt worry, ive not got old enough to slow right down yet

[Sir Nibble]

Look at that a narrowboat that moves.

I've clocked my boat down Caen hill at the speed of flight.

[Kez]

We normally go at about 2 1/2 knots, 'cos Linnet needs advanced warning to stop

[Neil TNC]

Our fast trip from Sharpness to Portishead was heavily influenced by our pilot who overheard the 'first mate' on a launch beside us say something like "I hope they don't let that old barge out in front of us - they are so slow" - outside the lock gates, the pilot said "OK, open her up and let's see what she can do" at that point the tide was still coming in and the other boats were barely making headway - we made about 5 mph flat out but within half an hour or so we were well out in the channel, we had the tide in our favour and most of the other boats were a long way behind - you can't even see them (except as specs in the distance) in the photo below . . .

 

 

We have found the Severn Estuary pilots a good laff.

On one passage (upstream) we had some plastic boats in front. Just after the bridge, the pilot said "Shall we burn them off, you are only 2ft draught aren't you?".

So we came out of the navigation channel (along the north bank at that point) and over the sands, which was the flood channel. Suddenly without touching the throttle we had the wind in our hair and we shot off!

We arrived at Sharpness early, just ahead of the plastic boats, before HW. This in itself was interesting as the pilot insisted the "Cap'n" always steers into port, so it was a full tilt at 45 degrees to the flow arrival between the breakwaters.

Our last passage downstream we foned the duty pilot on the morning of departure, expecting a "stop" as it was a bit windy. The pilot (who, by chance was the same one we used the time before) said "I would not normally go down with a narrowboat in these conditions, but as the wind will be going off and I know the boat, let's go for it!" He also said as it was only neaps, there would not be the usual boiling at The Shoots, but it would be a bit yumpy off Avonmouth. He was of course proved to be compleatly accurate. We also had to phaff around as a Car carrier was leaving Avonmouth.

This was the first and last time we used Portishead Marina. As a matter of interest I managed to obtain a discount, by saying we were from a visiting "boat club"!

 

Another reason why a steel narrowboat can be more usefull than a plastic boat when traveling up tidal inlets, early on in the flood is the shallow draught and the fact that it dooes not matter if you whack the bottom. On one occasion we pulled off and started up the Avon a bit early so as to miss the traffic that Avonmouth reported was about to occur. We heard a yot on the VHF to Avonmouth and he seemed a bit miffed that a "barge" was going in front. We knew we were early on the flood, so just abled up on tickover. After a while the yot started tailgating us. I got on the roof, bunged the long shaft in (graduated in foot stripes) and pointed out that there was only 5ft of water. The yot then slowed right down!

[alan_fincher]

OK,

 

I admit it - it's a toy, but having great fun with the newly acquired GPS.

 

The trip to the banter and down the Wendover Arm was the first chance to try our own, rather than just viewing somebody else's.

 

To those of us new to them, I find the claimed accuracy on position, (often within 10 feet, never over within 20 feet), quite stunning.

 

It records a tracklog of where it's been, which you can upload directly into Google Earth, and see your course plotted on an aerial map.

 

I was quite surprised to be able to see....

 

1) Where we pulled over to secure a "moored" boat that wasn't.

2) Reversing a short distance on the arm, to give someone a better place to pass.

3) Moves made winding, and reversing back to the very end.

4) Having to emergency stop, then reverse to avoid a rowing skiff that decided he was going to take off across my bows when turning in to the marina.

5) The boat leaving and arriving back at exactly the right pontoon.

 

Yes, a toy, but also very informative about those times when more revs, (and more fuel), aren't actually meaning more speed.

 

Our (fairly shallow drafted) boat makes about 2.5 to 3.0 mph on the Arm, versus 3.8 to 4.0 mph on the summit, so maybe about 1 mph slower, most of the time.

Mind you most of the boats we "bantered" with were big vintage engines, and draughts of maybe 3 ft. I suspect the Wendover would slow them down a bit more than us - the three who went down were the shallow draughted ones.

[Naughty Cal]

Narrowboats want birching.

 

Went for a little jolly into Lincoln yesterday, anchored up in the pool for a couple of hours watching the world go by. After a couple of hours a narrowboat comes through the glory hole waves hello and pootles off. Half an hour later we decide to lift anchor and head off back to home base which is about 45 mins away if you stick to the speed limit of 5mph out of lincoln. So we head back, doing about 3.5mph through lincoln past the moorings and low and behold the narrowboat hasnt made it through yet and is seen ahead. Now our speed log was registering 3.8mph all the way back to the marina and we were gaining quickly with a line of boats behind us.

 

Why having seen us and our line of ducklings did they not pull over and let us past. Fair enough if you are the only boat out there do whatever speed you wish, but not when holding others up in the process.

[bottle]

Perhaps.......................

 

It was ignorance of this one boater.

 

Perhaps......................

 

The boat was under powered (not something you would understand )

 

Perhaps........................

 

This boater did not know of the higher speed limit on that stretch of water.

 

and travelling at 3.8mph gives one greater time to admire the scenery and chill.

Edited March 2, 2009 by bottle

[Naughty Cal]

Perhaps.......................

 

It was ignorance of this one boater.

 

Perhaps......................

 

The boat was under powered (not something you would understand )

 

Perhaps........................

 

This boater did not know of the higher speed limit on that stretch of water.

 

and travelling at 3.8mph gives one greater time to admire the scenery and chill.

 

The very large signs saying 5mph make it very clear what the speed limit is.

 

It did seem to have a issue with the engine though given the large amount of noise and no gain in speed.

 

3.8mph would have been lovely had we not taken the canopy off when it was sunny earlier in the day however it was bl**dy freezing and the engine was smoking like an old man (it dont like going that slow) so i was bathing in a fog of diesel at the back. so admiring the scenery would have been easier could i see it and i was chilled, very chilled

[alan_fincher]

I'm not sure we could make a consistent 5mph, even if we wanted to.

 

Many older boats can't.

 

If you were behind us, and I tried, you might get more asphyxiated by our engine than yours.

[Naughty Cal]

I'm not sure we could make a consistent 5mph, even if we wanted to.

 

Many older boats can't.

 

If you were behind us, and I tried, you might get more asphyxiated by our engine than yours.

 

But would you pull over when it became clear you were holding up a lot of boats?

[Nine of Hearts]

But would you pull over when it became clear you were holding up a lot of boats?

 

Slightly off-topic but on the subject of pulling over, listening to the radio last month they had a discussion between an "all caravanners must be shot" person and someone high up in the Caravan Club of GB. When the former complained that caravan towers consistently held people up, the latter claimed it was the explicit policy of the Caravan Club to pull over and let people past. In 26 years of driving on British roads, this has never happened to me. Am I extremely unlucky or what?

[Tam & Di]

But would you pull over when it became clear you were holding up a lot of boats?

 

Did you make it obvious you wanted to overtake? Obviously it's uncommon for UK boaters to use VHF (though I believe you do), but I would have come up onto his arse end, leaving little doubt as to my intention, and sounded a horn if necessary. Not so easy then if he does decide he's not going to give way though, unless the waterway is indubitably wide and deep enough.

 

I would not expect to pull over myself if I knew the channel was narrow or I was coming to a bridgehole, or if there was a lock a few minutes away and I knew I would get held up, but otherwise I don't see why there should be a problem.

Edited March 2, 2009 by Tam & Di

[Naughty Cal]

Did you make it obvious you wanted to overtake? Obviously it's uncommon for UK boaters to use VHF (though I believe you do), but I would have come up onto his arse end, leaving little doubt as to my intention, and sounded a horn if necessary. Not so easy then if he does decide he's not going to give way though, unless the waterway is indubitably wide and deep enough.

 

He wasnt using VHF although most of us following were!!!

 

We made it pretty obvious we wanted to overtake. I would have thought the anchor staring him in the face would have done it. If the river had been a nats wider we would have gone for the overtake but it wasnt worth thrashing the prop into the mud to gain 15-20mins extra.