how fast

[russ]

Why is it that the Windsor passenger tourist boats can over take me at speed when i am cruising at 5 knots as shown on my GPS?
They're the professionals and should know better or am I still too much of a novice and that I should have kept a matched speed ahead?

 

[jessie]

Or how about, the safety boat, an Orange rib causing more than excess wash after the open water swim at Windsor today.

 

[Andrew_Fanner]

Why is it that the Windsor passenger tourist boats can over take me at speed when i am cruising at 5 knots as shown on my GPS?
They're the professionals and should know better or am I still too much of a novice and that I should have kept a matched speed ahead?

Schedule? On the whole I let them go by.

 

[apollo]

Bit like this dude from Cliveden, 4.3 knots my Rrrrrs
http://www.youtube.com/watch?v=fYb91OytHMs

 

[boatone]

Or how about, the safety boat, an Orange rib causing more than excess wash after the open water swim at Windsor today.

The organisers of the swim are in rather deeper water than just a speeding RIB.
They were supposed to have notices at both ends and also there was to be a navigation channel clearly marked along the north bank. Neither happened.
ISIS turned up towards the end of the event and I heard them challenge a safety boat as to why there were no signs.

Also, saw the safety boat instruct two cruisers to stop proceeding downriver and tie up as the river was closed - which was not intended to be the case as the EA notice only announced a restriction.

 

[cereal tiller]

passenger vessels are subject to the EAspeed limits,if you see one exceeding the limit,you can report it to the EA or the operators.

rowing launches are the single exception,but only when they are in the company of rowing boats.

the passenger boats that ply between windsor promenade and boveney weirpool used to advertise a time of 35 minutes to complete the round trip.

a few years ago,the EA pointed out that the 35 minute trip should take around 42 mins.

not all trip boat skippers are well seasoned professionals,some are students and seasonal staff

 

[mlines]

Bit like this dude from Cliveden, 4.3 knots my Rrrrrs
http://www.youtube.com/watch?v=fYb91OytHMs

Looking up Suzy Ann shows it to be 9.9 metres long.

Stop framing the video shows it takes approx. 3 seconds to pass a known point.

This approximates to 3.3m/s or 12km/h or 6.47 knots

 

[apollo]

I like your science, but it was definately more than 6.5knots, suspect you have slow internet connection. I would have put it in the 7-8k bracket

 

[thamesS23]

He would off been going faster but his fenders were slowing him down !!

 

[apollo]

Quite possibly, still gives the people knocked into the water something to grab hold of...

 

[watson1959]

Speed

Looking up Suzy Ann shows it to be 9.9 metres long.

Stop framing the video shows it takes approx. 3 seconds to pass a known point.

This approximates to 3.3m/s or 12km/h or 6.47 knots

Good to see you yesterday Martin.....however shouldnt you be working instead of reading posts in here?

Opps.....suppose I should also be working instead of posting...bugger! Caught again...

 

[mlines]

I like your science, but it was definately more than 6.5knots, suspect you have slow internet connection. I would have put it in the 7-8k bracket

Stepping frame by frame means I can do it what ever the speed of the internet and the Internet here at work is certainly not slow

The only issue would be dropped or missing frames in the orginal (but that would make it faster than it should be). There is also an "angle" issue. The camera is a point, the boat is moving across the bottom of a triangle formed by its start point, finish point and the camera whilst the distance is being approximated by the triangle of the camera and two points on the bank which are further away.

Looking at the video I would have thought that 6-7 knots was about right. My planing boat goes over the hump to the plane at between 10-12 knots and that does not look close to the speed at which mine switches to the plane.

Martin

 

[mlines]

Good to see you yesterday Martin.....however shouldnt you be working instead of reading posts in here?

Opps.....suppose I should also be working instead of posting...bugger! Caught again...

- online research and keeping up with current affairs! Its just that my version of current is different to works understanding of current!

 

[No Regrets]

A very low wash however

 

[apollo]

A very low wash however

Nah, just never really shows in photos.

 

[cereal tiller]

low wash

the wash or surface disturbance is ,as you express,modest.
however,the reduction of speed,by engaging reverse gear is less effective than a transom stern of current design.
the thames speed limitations not only consider wash and draw parameters,they also take into account stopping/manouvering distances.
the speed limit does apply to every powered river user.
the easy and definitive method of determining excess speed is to observe the "second"stern wave,if it is "breaking".the speed is more than depth and /or channel width will accomodate.