harecastle tunnel

[canal boat man]

does anybody know the air draft in harecastle tunnel. i have tried to measure my 4year old narrowboat from the waterline to the highest point, in my case, with chimney and wind generator discounted a mushroom vent, this measures about 6' 3'' or 75 inches.

[NB Phoenix]

does anybody know the air draft in harecastle tunnel. i have tried to measure my 4year old narrowboat from the waterline to the highest point, in my case, with chimney and wind generator discounted a mushroom vent, this measures about 6' 3'' or 75 inches.

 

 

Harecastle Tunnel headroom 5ft 9in (1.74m)

[Nickhlx]

Harecastle Tunnel headroom 5ft 9in (1.74m)

 

 

you'll have to let the tyre down a bit then !!

 

Nick

[John Orentas]

The air draft dimensions are published all over the place all with minor variations, but I would certainly say that any sensible size narrowboat would not have any kind of problems in the Harecastle..

 

Even in the early days of the 1970's when much of the towpath was still in place and the tunnel roof dipped alarmingly in places I never knew of any boats not making the passage.

[alan_fincher]

I'll admit I've not been through for (very) many years.

 

But I'm over 6 foot, and stood on a cruiser stern I'm damn sure that at no point did I have to duck as much as a figure of 5 foot 9 inches implies.

 

I think that figure must include a very hefty margin of error!

 

Alan

Edited May 18, 2008 by alan_fincher

[Tim Lewis]

I'll admit I've not been through for (very) many years.

 

But I'm over 6 foot, and stood on a cruiser stern I'm damn sure that at no point did I have to duck as much as a figure of 5 foot 9 inches implies.

 

I think that figure must include a very hefty margin of error!

 

Alan

 

Very much agree, the height in the centre must be at least 7'6". Obviously air draught should allow for the height out of water at the sides of the roof but as Harecastle was originally built with a towing path I would consider that the 5'9" figure to be well out.

 

Tim

Edited May 18, 2008 by Tim Lewis

[Timleech]

Very much agree, the height in the centre must be at least 7'6". Obvioslt airdrauught should allow for the height out of water at the sides of the roof but as Harecastle was originally built with a towing path I would consider that the 5'9" figure to be well out.

 

Tim

 

I brought an ex-BW dredger through last autumn. The tunnel keeper's first response was along the lines of 'you're not taking that thing through here, it'll never fit!'. A couple of phone calls established to his satisfaction that the same craft had already been through the tunnel, though he was still adamant that it had to clear the gauge before he would let us in. In fact one of the legs did just touch the gauge - would have missed if we'd been a few inches over to the other side - but we had ample clearance (albeit only inches in some parts) all the way through after resetting the back actor boom to be lower than its normal travelling position. If your handrails are close to the gauge you might have to accept losing some paint on the way through as being part of the experience.

 

 

Not the lowest point, but close.

 

Tim

[RupertG]

I brought an ex-BW dredger through last autumn. The tunnel keeper's first response was along the lines of 'you're not taking that thing through here, it'll never fit!'. A couple of phone calls established to his satisfaction that the same craft had already been through the tunnel, though he was still adamant that it had to clear the gauge before he would let us in. In fact one of the legs did just touch the gauge - would have missed if we'd been a few inches over to the other side - but we had ample clearance (albeit only inches in some parts) all the way through after resetting the back actor boom to be lower than its normal travelling position. If your handrails are close to the gauge you might have to accept losing some paint on the way through as being part of the experience.

 

Tim

 

Perhaps someone could go through with an ultrasonic tape measure strapped to an upright? You'd probably want one person steering and the other taking readings: not sure I'd like to do both at once.

 

You can get quite good ones for around a tenner from Deal Extreme (the world's most dangerous website - I have pals with serious £30 a month habits). In fact, if anyone's going to be in London and thence through the tunnel, and feels like doing it, I'd be happy to get one and lend it out for the cause in exchange for a beer. Any excuse to buy gadgets (and drink beer).

 

 

Aaaaaactually, if I had my dream of a proper floating geekerie, I'd get one of these

 

 

and have it logging automatically to the server. But then I'd have to build a rotating scan head to produce a tunnel profile - slip ring commutator or bluetooth data link? And then hook it into the autopilot to keep an optimum heading.

 

Would have to build the autopilot first of course, but then that's higher on the list anyway as part of my ropeless mooring plan. Imagine if you could just park the boat a foot away from the bank and it would keep itself there without any physical connection - is that an actual mooring? What if you program the thing to inch forward a foot an hour? Puts a whole new light on continuous cruising. And mooring charges.

 

Sorry. This isn't helping. Y'know, if I do get my watery Evil Scientist Stronghold (what am I saying. WHEN I do get...) I'll have to call it NB Drifting Topic.

 

R

 

(you should see the plans for the directed energy ned repeller - just waiting for this to hit the government surplus market)

[canal boat man]

I brought an ex-BW dredger through last autumn. The tunnel keeper's first response was along the lines of 'you're not taking that thing through here, it'll never fit!'. A couple of phone calls established to his satisfaction that the same craft had already been through the tunnel, though he was still adamant that it had to clear the gauge before he would let us in. In fact one of the legs did just touch the gauge - would have missed if we'd been a few inches over to the other side - but we had ample clearance (albeit only inches in some parts) all the way through after resetting the back actor boom to be lower than its normal travelling position. If your handrails are close to the gauge you might have to accept losing some paint on the way through as being part of the experience.

 

 

Not the lowest point, but close.

 

Tim

Very helpfull thanks for your response and not just quoting the 5' 9'' as quoted in the books.

Dave

[canal boat man]

I'll admit I've not been through for (very) many years.

 

But I'm over 6 foot, and stood on a cruiser stern I'm damn sure that at no point did I have to duck as much as a figure of 5 foot 9 inches implies.

 

I think that figure must include a very hefty margin of error!

 

Alan

Thanks for your help.

 

Dave