Princess crashes into Richmond Bridge

[Uricanejack]

I am yes. Though unfortunately with that comes the added pressures of pleasing and serving either paying guests or private individuals, and placing myself in situations that are uncomfortably challenging. This is in no way deflecting the responsibility I have to the safety of all on board and the boat, only it's an extraneous influence in my decision making. In a nutshell, my lack of experience on the river put me in that position, live and learn.

Tiss always the way.
There is always pressure. Ether imagined or spelled out in detail.
Some times we just put pressure on ourselves feeling we should do something because some one else can do it. Or did it.
We measure ourselves by our ability to accomplish.

Sometimes the thing to do is say this is not a good idea, before hand rather than I wish we didn’t try it after it all went wrong.
While it may not always go over without disappointment if you explain why it usually works out ok.

In the end a pro is hired to ensure bad things don’t happen. Those who hire them if wise will listen.

Those who won’t listen to good judgment aren’t worth working for.

One thing I can say from experience is after it goes wrong, don't expect many of them will thank you for trying.

Experience is something you accrue from making mistakes.

 

[Observer]

Each to their own I suppose but my purely personal view on this is pretty much the same as Deleted User's. Basically, rudders bring absolutely nothing to the party. In a planing boat like this with twin screws and nice engines that maintain 600rpm when you put them into gear and 45inch pitch props, I'd have absolutely all the thrust I need in any direction from the props. (you wouldn't with the fine pitch props of a D boat; but this is a P boat with coarse props). The last thing I'd ever want to do is to speed up so as to increase steerage. The rudders just don't add enough benefit to the proceedings.

Now if you love the rudders you could do the reverse-through thing, and have say 4kt STW and 1kt backwards under the bridge if you want, but I'd much prefer to do it forwards and move the boat exactly where I want using fwd and rev, but mostly rev to keep SOG to a knot or so, plus big side thrust in either direction from the kick of those 40P props.

On a small technicality I don't agree with those who say you could "lose the bow to the current" if pointing into the current and doing this backwards. You'd be driving the boat forward at 3-4 knots STW (with reverse 1 knot SOG or whatever under the bridge ) and you NEVER lose the bow in that scenario. You don't lose the bow if you drive a boat forwards STW 3 knots, ever, and that's all you'd be doing here.

No big deal and best wishes to Mr Skinner. As others have said we all make mistakes and the differences tend to be whether there are video cameras around. He clearly made a mistake when he allowed the boat to turn sideways on, too soon after he reversed out, and he should have stopped that anticlockwise spin of the boat at its inception, with a dollop of stbd reverse, plus b/thruster to port to stop the bow going too far to starboard as he kicked the stern back to the left. But 3 seconds of confusion/hesitation/looking the other way at something else that is worrying you (which can easily happen - I'm not condemning) and it can be too late. I'm 100% sure he knows that so it is hardly worth mentioning. It's all water under the bridge now

I was wondering if you would weigh in jfm. As expected, your analysis is completely rational and supported by explanation of your conclusion. Best regards to you.

 

[U4]

OF I accept your greater knowledge on this but is your boat single or twin screw?

I agree with Mike on this. In a twin screw, you have loads of control of the bow using each engine as required. if you hold the boat against the tide using reverse thrust (each or both engines as required) you have a bunch more control of where the bow ends up than you would if the bow (given how light it is in comparison to the rest of the boat) was facing upstream.

 

[Uricanejack]

Each to their own I suppose but my purely personal view on this is pretty much the same as Deleted User's. Basically, rudders bring absolutely nothing to the party. In a planing boat like this with twin screws and nice engines that maintain 600rpm when you put them into gear and 45inch pitch props, I'd have absolutely all the thrust I need in any direction from the props. (you wouldn't with the fine pitch props of a D boat; but this is a P boat with coarse props). The last thing I'd ever want to do is to speed up so as to increase steerage. The rudders just don't add enough benefit to the proceedings.

Now if you love the rudders you could do the reverse-through thing, and have say 4kt STW and 1kt backwards under the bridge if you want, but I'd much prefer to do it forwards and move the boat exactly where I want using fwd and rev, but mostly rev to keep SOG to a knot or so, plus big side thrust in either direction from the kick of those 40P props.

On a small technicality I don't agree with those who say you could "lose the bow to the current" if pointing into the current and doing this backwards. You'd be driving the boat forward at 3-4 knots STW (with reverse 1 knot SOG or whatever under the bridge ) and you NEVER lose the bow in that scenario. You don't lose the bow if you drive a boat forwards STW 3 knots, ever, and that's all you'd be doing here.

No big deal and best wishes to Mr Skinner. As others have said we all make mistakes and the differences tend to be whether there are video cameras around. He clearly made a mistake when he allowed the boat to turn sideways on, too soon after he reversed out, and he should have stopped that anticlockwise spin of the boat at its inception, with a dollop of stbd reverse, plus b/thruster to port to stop the bow going too far to starboard as he kicked the stern back to the left. But 3 seconds of confusion/hesitation/looking the other way at something else that is worrying you (which can easily happen - I'm not condemning) and it can be too late. I'm 100% sure he knows that so it is hardly worth mentioning. It's all water under the bridge now

As a rare visitor to this forum from the other one. Far be it from me to disagree with a resident expert. Sorry I just can't resist the temptation.
like you I wouldn't be coming in backwards. I think that's out to lunch.
Rudders if you use em they are very handy thing's
Relying solely on the twist effect of twin screws is only good up to a point and varies with the ratio of width and power to length and directional stability.
Proper use of the rudder's can greatly improve your directional control.
Like you I'd say this lose the bow to the current is twaddle.

My opinion is your vessel will be pushed bodily sideways by a current which is very slightly one side or the other of your intended direction or heading. Its extremely unlikely the current will be parallel with your intended direction of travel.
An other problem the current will almost certainly bring to the table is a sheer close to the abutments as the flow is diverted by the abutment.

Like you I would recommend a slow approach.
Steerage way is not required to take advantage of the rudders. they are not much help going astern
A twin screw with a single rudder on the centerline is missing a very help full manoeuvring tool.
Prop wash past a rudder.
This will give you considerably more control over the movement of the stern.

If you use your rudder's you can parallel park a twin screw vessel equipped with a BP.

If you steer your bow where you want it to go. You can kick your stern up into the current using your rudder.
Go slowly min speed through water your pivot point with a shot of power will stay well forward and your stern will come up more than your bow will fall off.
I tend to plan not to use BP. But it will help keep bow where you want it., If you need it.

If you know you are likely to get a sheer you can anticipate its effect and counter a sheer very effectively with the rudder.

Sorry I just couldn’t resist disagreeing about using rudders. Bridge or no bridge.
And I have to admit the only Princess I've ever driven was made by British Leyland back in the 70's and it was a rust bucket.

 

[MapisM]

If you steer your bow where you want it to go. You can kick your stern up into the current using your rudder.

Mmm... I'm not sure to understand the point you're trying to make with your train of thoughts overall, but this statement grabbed my attention, because sorry, but I think it just doesn't make any sense.
With the boat and the STW which is being discussed, if there's any kick you can hope to give to your stern, it's only the sheer power of the mains that have a chance to provide it.
I doubt that even a stern thruster could be very effective, unless much more powerful than those usually fitted in this type of boats.
But rudders? Not a snowball's chance in hell, imho.

 

[Uricanejack]

Mmm... I'm not sure to understand the point you're trying to make with your train of thoughts overall, but this statement grabbed my attention, because sorry, but I think it just doesn't make any sense.
With the boat and the STW which is being discussed, if there's any kick you can hope to give to your stern, it's only the sheer power of the mains that have a chance to provide it.
I doubt that even a stern thruster could be very effective, unless much more powerful than those usually fitted in this type of boats.
But rudders? Not a snowball's chance in hell, imho.

Sorry
Perhaps I did not explain it very well. I will try again just the concept of using the rudders at minimum or even no way through the water.

A rudder with no flow of water passing does nothing.
A flow of water can be the result of the vessel moving through the water. This is what most people traditional think of.

Or the rudder can be used effectively. With prop wash passing the rudder being the water flow past the rudder.
Twin rudders used in conjunction with twin screw on a vessel.
The rudder in line with the screw used ahead will have significant effect when it deflects the flow of water.
The rudder in line with the screw used astern will have little or no effect due to no wash passing the rudder. No was no flow.

Even when a vessel is making way through the water. The rudder with the prop wash will have considerably more effect than a rudder without prop wash.

Occasionally vessels are fitted with an option for independent rudder control. Which in some circumstances can be useful. Though I personally find it just an additional complication which doesn’t make enough difference to be worth my while.
One occasion it may come in handy is when going astern for a distance or into a confined space independent rudders allow for one screw to be operated astern while the other is operated ahead and provide steering. I just have never found this feature to be significantly more effective.
Or you can set both rudders the positive way eliminating the need to center rudders when changing which screw is providing ahead thrust. This feature can be handy. Set em up and you need one less hand

Effective use of twin rudder’s in conjunction with thrust from one of the screws on a twin screw vessel is considerably more effective than any stern thrusters system I have experience off.

Just another tool in my box of tricks.

Of course I have no experience with Princess boats so I don't even know if they actually have one rudder two rudders or no rudders.

 

[MapisM]

Of course I have no experience with Princess boats so I don't even know if they actually have one rudder two rudders or no rudders.

LOL, well, I can't pretend to be a Princess expert either, but I would dare confirming that she does have a couple of rudders, in line with the props, and no independent control.

Anyway, I agree in principle that rudders aligned with shafts become a bit more effective, for any given STW, when the screw is working hard (proportionally to the speed).
The point is - at least in my experience with planing boats on shafts, at maneuvering speed - that a sudden prop burst on one side, due to both the asymmetric trust and the prop walk effect, is already pretty effective per se in kicking the stern.
You might well add the rudders to the equation, notihng wrong with that, but their effect is negligible compared to a tad more/less throttle - not to mention if you use both engines in opposition.
All imho, as always.

 

[JumbleDuck]

I seem to remember an old saw: the man who never made a mistake, never made anything.

"After we had conducted thousands of experiments on a certain project without solving the problem, one of my associates, after we had conducted the crowning experiment and it had proved a failure, expressed discouragement and disgust over our having failed to find out anything. I cheerily assured him that we had learned something. For we had learned for a certainty that the thing couldn't be done that way, and that we would have to try some other way."

-- Thomas Alva Edison, interviewed in American Magazine, January 1921

 

[capsco]

I agree with Mike on this. In a twin screw, you have loads of control of the bow using each engine as required. if you hold the boat against the tide using reverse thrust (each or both engines as required) you have a bunch more control of where the bow ends up than you would if the bow (given how light it is in comparison to the rest of the boat) was facing upstream.

I suggest you read JFM post.

 

[U4]

I suggest you read JFM post.

Noted and thank you for the suggestion

 

[Hurricane]

As a rare visitor to this forum from the other one. Far be it from me to disagree with a resident expert. Sorry I just can't resist the temptation.
like you I wouldn't be coming in backwards. I think that's out to lunch.
Rudders if you use em they are very handy thing's
Relying solely on the twist effect of twin screws is only good up to a point and varies with the ratio of width and power to length and directional stability.
Proper use of the rudder's can greatly improve your directional control.
Like you I'd say this lose the bow to the current is twaddle.

My opinion is your vessel will be pushed bodily sideways by a current which is very slightly one side or the other of your intended direction or heading. Its extremely unlikely the current will be parallel with your intended direction of travel.
An other problem the current will almost certainly bring to the table is a sheer close to the abutments as the flow is diverted by the abutment.

Like you I would recommend a slow approach.
Steerage way is not required to take advantage of the rudders. they are not much help going astern
A twin screw with a single rudder on the centerline is missing a very help full manoeuvring tool.
Prop wash past a rudder.
This will give you considerably more control over the movement of the stern.

If you use your rudder's you can parallel park a twin screw vessel equipped with a BP.

If you steer your bow where you want it to go. You can kick your stern up into the current using your rudder.
Go slowly min speed through water your pivot point with a shot of power will stay well forward and your stern will come up more than your bow will fall off.
I tend to plan not to use BP. But it will help keep bow where you want it., If you need it.

If you know you are likely to get a sheer you can anticipate its effect and counter a sheer very effectively with the rudder.

Sorry I just couldn’t resist disagreeing about using rudders. Bridge or no bridge.
And I have to admit the only Princess I've ever driven was made by British Leyland back in the 70's and it was a rust bucket.

I'd given up replying to this thread but this is SO outrageous that I've got to comment.
Not only do I have some small experience with Princesses, I actually own a Princess 67 - same model as the one in this thread.

JFM is absolutely correct and I'm sure that most on this forum will totally agree.

Our rudders are almost completely useless until the boat is making way through the water at, at least 4 knots - and even then not a lot of use either.

Four your info, the P67 in this thread is the same as most flybridge boats and has two small rudders placed almost immediately aft of the props
When the props are turning at slow speed, they have very little effect on steerage.
This said, sometimes when the boat is not moving fast enough for the rudders to have any effect, I do often use them, particularly for very tight turns
The P67 is fitted with "fly by wire" ruder controls so it is very easy to convert from fully one "lock" to the other.
For me, for maneuvering, the rudders are only any use if you want to turn the boat in its own length, in which case I "split the throttles" (one engine forward and one astern) and use what there is a rudders to help the turn.
Other that that they are completely useless in slow speed maneuvering.

You also imply that the bow won't "fall off" if facing into the stream.
I don't know what kind of boat you are use to - maybe one with a large keel
But you have to remember that these flybridge boats are essentially "flat bottom" and have very little resistance to any sideways drift.
For me, it is the stern that is important - if you can keep the "props" in safe water, the bow will "fall away" (being influenced by external effects - tide, stream and wind etc)
That is why I say "hang on the props"

Now then - would I go through that bridge forwards or backwards - neither - this is not the place for this kind of boat
I'm sorry but attempting that kind of thing is foolish and the skipper shouldn't have done it.
Maybe I'm not as brave - but I wouldn't have done it
If I really had to do it, I would have kept the stern into the stream which is what I think this skipper did anyway.

Remember also, this boat is just short of 50 tons and had two and a half thousand horsepower available.
Sorry wrong boat wrong location.

Oh yes - and you are very wrong about the rudders

EDIT
I've just found this pic on my Photobucket account - this is the rudder arrangement on the P67
Note that the props are the lowest part of the boat in the water - the rest is, essentially "flat bottom"

 

[rafiki_]

I 100% agree with Hurricane. Having done a lot of ditch crawling, I am pretty comfortable in understanding what to do when with current and wind factors. When the current is flooding, if there is any sort of complication with a bridge or lock, I don't attempt it. I never use the rudders on my Azi when manouevering, only the props. I keep the speed to as slow as possible and nudge each engine in and out of gear as required. The rudders only come into play at 5 kn+, and even then they are not very responsive.

 

[kcrane]

On a small technicality I don't agree with those who say you could "lose the bow to the current" if pointing into the current and doing this backwards. You'd be driving the boat forward at 3-4 knots STW (with reverse 1 knot SOG or whatever under the bridge ) and you NEVER lose the bow in that scenario. You don't lose the bow if you drive a boat forwards STW 3 knots, ever, and that's all you'd be doing here.

I'm trying to imagine actually doing the "reverse through the bridge" manoeuvre. I think you are saying that, if you are in a river running at 4knts, and you drive forward into that stream at 3knts then the bow isn't going to fall off any more than it would if you were in still water driving forward at 3knts. The difference between the two is that in one case your speed over the ground is -1knt (hopefully reversing through the bridge) and in the other it is +3knts. The bow of the boat doesn't 'know' the difference.

I can intuit that quiet easily, and it is intuition I need when driving a boat as I'm too slow to work it out from first principles when I panic

So, I'm sliding the boat back by driving forward slower than the speed of the stream and I'm getting close to the bridge, wondering if I will fit underneath. The trouble is my boat drives forward at 5knts in idle, so I'm having to slip in and out of gear to do less than 5knts, so my speed is varying, as I can't provide a steady power source. Once near the bridge I keep the power on for longer to go ahead slightly faster, up to 4knts, to slow while I check the gap. The boat is now going to act as though it is going forwards at 4knts.

If I start juggling the throttles to try to move left or right I will likely move the boat out of line with the stream, and a 4knt current will catch one side of the bow or the other. Um, not sure I like the sound of that. I think, again intuition, that I'd hold the boat in the stream on both engines, but try and move left and right with bow & stern thrusters working together. They couldn't hold me against the stream, as the P67 discovered, but they would move me left and right. I wouldn't be in a hurry to touch the wheel, something I never do when manoeuvring.

The above just me pondering how it could work, truth be told I wouldn't risk that bridge in that boat in those conditions.

 

[longjohnsilver]

The above just me pondering how it could work, truth be told I wouldn't risk that bridge in that boat in those conditions.

My thoughts as well. Rather than risk damage or worse, I'd tie up somewhere and wait for lower water and less tide/current. I've learnt over the years after many aborted trips, normally to go diving, that taking risks just isn't worth the hassle, there's alway another day to look forward to, rather than looking back with regrets.

 

[Deleted User YDKXO]

I'd given up replying to this thread but this is SO outrageous that I've got to comment.

+1 No offence intended to Uricanejack but he's obviously never driven a twin engined planing hulled boat

 

[Richard Shead]

My thoughts as well. Rather than risk damage or worse, I'd tie up somewhere and wait for lower water and less tide/current. I've learnt over the years after many aborted trips, normally to go diving, that taking risks just isn't worth the hassle, there's alway another day to look forward to, rather than looking back with regrets.

Problem is he came up on the tide to get through the gates at Richmond (the half tide jobs) then about 20 mins to Teddington where he turned and took the tide back out in order to make the gates as well as have enough water to get through Brentford.

The only place he could have tied up would have been Teddington and wait but there would have been a real risk / art to getting the levels right in order to get through the gates at Richmond without using the half tide lock and risking low water below that.

I may have mentioned in another thread we used to crew a Princess 20 m for a very wealthy chap mooring it at Teddingoton and used to use Richmond up to Kingston as its "cruising" ground. It was very short lived mainly because his business did not allow him near the boat however we went through all the bridges and they were indeed tight. Not impossible but tight.

So I guess I am on par with Hurricane! except he OWNS the 67 I just helped out on the 20m on this stretch.. !

 

[longjohnsilver]

Ok Richard, my comments weren't meant in any way as a criticism, just an observation. I guess that large motor boats and this stretch of the Thames are not ideal bed fellows.

 

[Firefly625]

+1 No offence intended to Uricanejack but he's obviously never driven a twin engined planing hulled boat

Firstly, just like to say 100% agree with Hurricane, and as an owner of the same boat an excellent judge!

Just reading Uricanejack first post on the subject, he mentions that he does not come on the Mobo forum much, having a quick look and the chap seems to reside mostly on scuttlebutt, therefore my assumption is he's got a sailing boat. Now having sailed a little bit there is an incredible difference between how a motorboat reacts to steerage when engine is in neutral compared to a sailing boat. Took me by surprise when I first turned to motor... But for the simple reason as shown below comparing my rudder with my parents boat.....size is everything! Giving him the benefit of the doubt perhaps Uricanejack has not indeed helmed a large... or even small motor boat to experience the difference.

 

[Richard Shead]

Ok Richard, my comments weren't meant in any way as a criticism, just an observation. I guess that large motor boats and this stretch of the Thames are not ideal bed fellows.

I did not see it as a criticism dont worry, thought I would just give some background on why the big boats go as far as Tedd and the hassle it is to do it all on one tide and the lack of mooring etc

Cheers

 

[MapisM]

If I start juggling the throttles to try to move left or right I will likely move the boat out of line with the stream, and a 4knt current will catch one side of the bow or the other

Good point.
What has been said so far remains valid in principle, but if the min speed (mind, in reverse, if you make the attempt bow first, as more logical - and 5kts sounds like a helluva minimum reverse speed!), is higher than the current, thus requiring to engage/disengage the gear, that's bound to make life even harder.
Then again, I can't think of a better strategy, anyway.
Aside from the obvious one, i.e. not attempting the maneuver at all, as already suggested.