How much?

[Cdnwolf]

How much material would I need to bring down this bridge? It is 1100 feet long reinforced concrete in sections. It will be done by special forces.

[Cdnwolf]

:D Now they definately are watching us!!!!

[kato13]

My answer would be probably less than you think.

Raw numbers for an answer would probably be ok, but jf there are specific instruction on how to make the demolition more efficient please keep it in PMs.

[pmulcahy11b]

If you ask a combat engineer, the answer will always be "Twice as much..."

[pmulcahy11b]

:D Now they definately are watching us!!!!

A component of my diagnosis is paranoia, so I always think they're watching us!

[leonpoi]

what might be useful is (from a source book that I can't remember, plus some of my own interpreation) the following roughly applies:

Penetration needed to take down bridges
Wood: 22-28
Stone: 45-55
Metal: 55-70

the higher range will take down the bridge on a success, the lower range will on an outstanding success.

Now I'm rusty on DP and Pen. but taking reo as metal we might decide we need 70 Pen (strictly according to the rulebook this would give 7x250mm reinforced concrete penetration). if the charge was somehow tamped then the Pen is doubled -> Pen 35 worth of explosives -> 96 DP. A 1 kg block of plastic is 6 DP -> 16 kg of plastic. Who knows if this is realistic, but ignorance is bliss?? using the min amount if 55/2 -> about 60 DP -> 10 kg. So 10kg to damage and maybe destroy, 16kg to destroy. The sourcebook stated that a damaged bridge will collapse if a vehicle >10 ton (or maybe it was 8, I can't remember) is driven over it (high chance of collapse, about 80%. A construction/CVE test to determine how much it can hold), or if damaged again. If you can't tamp then the DP to destroy is 392 -> 65kg, so I hope that you can rationalise a method for doing so.

I'm guessing that this amount would be needed on each pylon if you really wanted to make a mess.

[Legbreaker]

What exactly do you mean by "bring down"?
Do you need the whole thing dropped into the river, pylons included?
Would cratering the road surface so as to prevent movement of traffic for 24 hours (while the engineers lay a new temporary decking over the hole) be sufficent?
Is the desired effect somewhere in the middle?

Time available is also a factor. Using boreholes to place the explosives within the structure itself well require much less explosive than if it were just laid against the surface. Naturally boreholes take time (if drilled) or are exceptionally noisy (if blasted with shaped charges, which still take time for the holes to cool down and allow safe laying of the actual demolition charges).

So, what it really comes down to is what it the teams plan and just how much can they carry?

[jester]

To many factors to give one answer. If I had time there are things I would do to make it much easier and thus require less demo. If you are using stealth to deal with to avoid any enemy sentries and such then you will have to do it old school and use ALOT!!!!

Some examples of bridge and other structure demo, just watch an implosion or the flick "Force 10 From Navarone" which will answer alot.

[Targan]

I think it would be dangerous and unwise for me to go into too many specifics about how to take down a bridge such as that but I would ask similar questions to Legbreaker's - how much of the bridge do you want to damage or destroy. If the goal is to breach at least part of the span and make it very difficult and expensive to repair, taking down one or both of the two main supports in the river would be the way to go but that would be a major undertaking. You would need many men each carrying alot of weight in tools and explosives.

How about floating a raft or barge down the river, packed with a tonne or two of ANFO? Tie that to a pylon and let it off and it would very likely destroy the pylon and drop the bridge and the prep time at the target would be only seconds or minutes (not including the getaway time).

[Cdnwolf]

The bridge would be the only remaining one crossing the Danube river and the only supply route for the Russian armies attacking Vienna - gone as in no chance in hell of replacing it. So basically is a suicide mission .... but nothing the characters can't handle!!

[Ramjam]

Just use a nuclear demolition charge like the US Army did in Black Madonna.

It's the only way to be sure.;)

[smokewolf]

The bridge would be the only remaining one crossing the Danube river and the only supply route for the Russian armies attacking Vienna - gone as in no chance in hell of replacing it. So basically is a suicide mission .... but nothing the characters can't handle!!

If this is your goal, as a former combat engineer I'd recommend that you don't want it gone completely.

You have three basic options:

1) Blow it to smithereens.
2) Damage it just right that it's both unusable and unsalvagable.
3) Weaken the bridge supports using cutting charges

Option #1 - with the bridge out of the way the Russian then move in pontoon bridging boats to construct a make shift bridge and continue on. While you will definitely have slowed them down, you've only done so by the time it takes them to move the pontoons to this area.

The task though will more than likely take your players more time and explosives to accomplish than the Russians replacing the bridge. :(


Option #2 - You blow only a small section of the bridge such that it twists down into the water. This requires a much smaller amount of explosives. The current of the water then works on the bridge and causes it to twist, break and contort enough to not only be unusable but unsalvagable. The Russians can still construct a pontoon bridge or equivalent across it, but in order to do so they must first demolish the remaining bridge.

This task should be quicker and cost less in explosives than Option #1 and will cause the Russians to spend more time and their own explosives to blow the remaining bridge. :)


Option #3 - You place explosives at key points on the bridge to weaken but not destroy it. When the Russians move their convoy across it next, it results in Option #2 but it takes a good portion of the convoy with it.

This task should be even quicker and cost less in explosives than Option #2 :D

[jester]

Lets look at some of the attempts by the Germans to take out the railroad bridge at Remagen.

Shelling it is costly, it would take pinpoint accuracy and lots of shells. Are the resources available? And would the Russians mount a counter attack?

Scuba divers with demolition charges on the underwater footings. This is possible, but is it practical? Do you have well trained divers and knowledge of the bridge and the pillings and riverbottom material? And of course a launch point that is secure to launch your forces from? And of course the materials, scuba or more likely rebreater gear, wet suits or dry suites, lights, timmers, igniters, lots of det cord to connect the charges and to use as wrapping to cut steel beams. And, of course the amount and quality of the explosives.

A comando force can sneak in and place charges on the reinforcing beams they can do this stealthfuly, placing them surgicaly, wraps of det cord and specific ammounts of charges in the support structures and key points that will allow it to fall under its own weight. The down side, you need to be stealthy and if caught you are screwed, or doing everything underfire which of course will cause the chances of failure to increase.

Or, just sieze the bridge! Go in, sieze it. On force conducts a holding action against the Russians trying to retake the bridge. A second force goes to work with torches and placing demolitions to weaken the bridge and ensure it falls when the charges go off. Downside, it can be a suicide mission for those on the bridge. They sit tight until it blows. OR, they can either escape via boats they have waiting below the bridge, or simply dive into the water and swim for it. Of course to ensure that is successful, you would want to place ALOT of anti personel mines and booby traps to slow up the enemy so they do not make it to tamper with your main charges.


As for me, I'd go for the stealth aproach. Wetsuited combat swimmers with demo packs placing the charges at the bridges footings where the steel meets the concrete and tamp them. If the footing of the bridge is parted it will come down. I would also use thermite bombs and det cord to cut through alot of the support beams. The cool thing, you only need to attack one side of the bridge, left or right side, one side of the bridge comes down it is unusable, all the forces will take it down, as you have longer spans that are unsupported. And when it comes time to rebuild, you still have 1 side still standing to possibly use should you want to rebuild.

Also, it would be a good idea to somehow cut the upper supports atop the bridge as they tie in alot of the support for the bridge.

Anyhow, those are some of the ways I would take it down. As for suppliest 2 dozen thermite grenades, 4 to six rolls of detcord, 8-12 satchell charges, 8 waterproofed satchell charges with enough detcord to connect them and two timers and shock cord or instant fuse.

Working primarily on one side, the upriverside would be my choice so you have the forces of the water working for you once the charges do blow.


1.) Thermite bombs go off burning through support structures that they are best suited to cut through. Lesser beams, steel support cables and similiar.

2.) Cutting charges blow cutting support structures, supporting and reinforcing beams and such.

3.) Cutting charge at the footing goes, this will cut the steel vertical girders that support the bridge.

4.) Underwater charges under the concrete footing supports go, these give the bridge one last shack to rock things loose, further break what has been cut and weakened, and blow away more of the concrete footers which coupled with the steel supports which have been cut or weakened should be enough to tumble the spans into the water. <Its kind of like chopping a tree, how a logger will notch it before starting on the primary cut, if we can eliminate first foot or so of the support pillars it will fall giving that much more stress on the already weakened structure>

The longest phase of the explosion will be the termite bombs burning, then after about 20 seconds of the thermite cutting, the charges go off in the order they are posted with three to five second intervals.

The danger, one explosion could damage the other charges, this they all need to be in independant systems as well as redundancy.

Anyhow, those are some of the things I'd think of and possibly try.

[Legbreaker]

My thoughts are that unless you've got a LOT of time AND explosives available, the piers aren't worth troubling with. Build to withstand not just the weight of the bridge, but flood waters as well, unless they've been constructed with demolition chambers built in, they're not going anywhere in this lifetime...

[jester]

I mean the steel structure above the piers, the piers or pillings are usualy concrete, and the footing of the bridge is usualy steel imbeded into the concrete. Where they merge however, you have to different materials joined, and that is usualy the weak spot. A meter or so up and you have all those stresses. The charge on the concrete pilling is more to cause a shacking of the bridge once its been damaged to help loosing up what has already been damaged or weakened by the prior explosives so that gravity can do its job.

Also, look at places where a steel pole is imbeded into concrete, there is always rust on the steel, again a weak spot that should be checked and exploited.

[pmulcahy11b]

Think about the Paul Doumer Bridge in North Vietnam. I'll grant you, it's not the same in situation or size (2500 feet cantilever construction), only analogous -- but the US repeatedly tried to drop that bridge and succeeded only in 1972 when smart bombs became available -- and then only put it out of service for a year.

I'm just saying -- it's never as easy as one thinks. That old military axiom, "No plan survives first contact."

[Targan]

I like Jester's idea of cutting through the steel support beams with thermite grenades. Most load-bearing points on a bridge like that will be too thick to cut through with det cord (if it was a suspension bridge det cord would be a viable option).

[kato13]

http://upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Jamestown_Bridge_demolition2.jpg/800px-Jamestown_Bridge_demolition2.jpg

This took 75 lbs or RDX and 350 shaped charges. Kinda beyond the scope of the mission but it is a pretty picture.

[pmulcahy11b]

This took 75 lbs or RDX and 350 shaped charges. Kinda beyond the scope of the mission but it is a pretty picture.

Is that the former Skyway in Tampa?

[kato13]

Is that the former Skyway in Tampa?

Jamestown Bridge (http://en.wikipedia.org/wiki/Jamestown_Bridge) in Rhode Island

[General Pain]

If you ask a combat engineer, the answer will always be "Twice as much..."


Yeah I thought I read that somewhere...do the math and then double it

[General Pain]

Just use a nuclear demolition charge like the US Army did in Black Madonna.

It's the only way to be sure.;)


I like the cut of your jib ;)

(homer simpson would then answer....what's a jib?)

[Cdnwolf]

Sorry I never got back to you guys. Knock at door and a talk with some guys who insisted on shining bright lights in my eyes.

Actually in Niagara Falls watching the sun rise... then doing the tourist thingie... and got me thinking... any nukes on the Hydroelectric plants in Niagara Falls.

[kato13]

Sorry I never got back to you guys. Knock at door and a talk with some guys who insisted on shining bright lights in my eyes.

Actually in Niagara Falls watching the sun rise... then doing the tourist thingie... and got me thinking... any nukes on the Hydroelectric plants in Niagara Falls.

Happened to be placing Canadian units so I was right there.

Closest canon nukes and how they relate to Niagra Falls, New York.

68.1 km ExSE of Hamilton, Canada, 1000 Kt
69.9 km SxSE of Toronto, Canada, 2000 Kt
164.4 km SW of Trenton, Canada, 750 Kt
272.1 km E of Sarnla, Canada, 1750 Kt
336.3 km ExNE of Windsor, Canada, 1000 Kt
350.4 km SxSW of Chalk River, Canada, 500 Kt
360.5 km S of North Bay, Canada, 750 Kt
373.5 km SW of Ottawa, Canada, 1500 Kt
401.9 km ExNE of Toledo, OH, 1750 Kt
474.0 km NW of Marcus Hook, PA, 1500 Kt
476.9 km NW of Philadelphia, PA, 1750 Kt
484.1 km NxNW of Fort Meade, MD, 500 Kt
482.9 km NW of Paulsboro, NJ, 500 Kt
485.7 km NW of Westville, NJ, 500 Kt
484.9 km NW of Linden, NJ, 1250 Kt
486.7 km NW of Delaware City, DE, 750 Kt
490.8 km NW of PerthAmboy, NJ, 1000 Kt
496.0 km NxNW of Arlington, VA, 500 Kt
496.8 km NxNW of Washington, DC, 250 Kt
492.4 km ExNE of Lima, OH, 750 Kt
511.2 km WxSW of Montreal, Canada, 2000 Kt
501.6 km NxNW of Camp David, MD, 500 Kt
510.6 km NxNW of Andrews AFB, MD, 500 Kt
529.6 km NxNW of Quantico, VA, 500 Kt
600.5 km NxNE of Catlettsburg, KY, 750 Kt

Closest canon units.
122.4 km ExSE of West German - 81st Panzer Grenadier Battalion (not a typo was in Canada to Train on TDM)
148.4 km SxSW of Canadian - 1/Toronto Regiment
178.6 km E of Canadian - 3/Regina Rifle Regiment
244.0 km WxSW of Canadian - 3/Toronto Regiment
373.4 km SW of Quebecois - 1/Regiment de Hull
408.2 km SxSE of West German - 53rd Panzer Battalion (not a typo was in Canada to Train on TDM)
486.5 km NxNW of US - 228th Infantry Brigade
505.3 km NW of US - 78th Infantry Division
564.8 km SE of British - 1/The Cheshire Regiment (not a typo was in Canada to Train on TDM)
574.3 km S of Quebecois - 1/Fusiiiers du St Laurent
610.5 km W of US - 43rd Military Police Brigade
624.8 km WxSW of Canadian - 1/Lake Superior Scottish Regiment
630.7 km WxSW of Quebecois - 1/Regiment du Saguenay
744.1 km WxSW of Quebecois - 1/Front de Liberation du Quebec
750.8 km S of Quebecois - 1/Regiment de la Chaudiere
884.9 km N of US - 184th Infantry Brigade
966.2 km WxSW of Canadian - 1/Royal New Brunswick Regiment
986.5 km ExSE of Canadian - 2/Toronto Regiment
1011.6 km WxSW of Canadian - 3/Princess Patricia's Canadian Light Infantry
1035.0 km WxSW of Canadian - 2/Queen's Own Rifles of Canada
1016.9 km N of US - 30th Engineer Brigade (Combat)
1093.8 km NE of US - 194th Armored Brigade
1154.3 km E of US - 84th Infantry Division (Light)

[Targan]

Actually in Niagara Falls watching the sun rise... then doing the tourist thingie... and got me thinking... any nukes on the Hydroelectric plants in Niagara Falls.
Someone can correct me if I'm wrong but I think I remember reading somewhere that by 2001 one of the Niagra plants was generating power again and the maintenance requirements and power generated were being equally shared by MilGov and one of the Canadian regional governments.

I think that is pretty good evidence that it wasn't nuked.

[kato13]

Someone can correct me if I'm wrong but I think I remember reading somewhere that by 2001 one of the Niagra plants was generating power again and the maintenance requirements and power generated were being equally shared by MilGov and one of the Canadian regional governments.

I think that is pretty good evidence that it wasn't nuked.


Give that man a prize. The following is from "Pennsylvania Crude"

Militia forces from Niagara Falls occupied and partially repaired the hydroelectric plant, providing the area with a trickle of semireliable power. The remnants of industries in Utica and Syracuse provided some material goods. The fields of western New York produced enough food to support the reduced population.

The year 2000 saw a decline in the region's fortune as more refugees sought entrance and then needed to be turned away. Western New York was forced to share the hydroelectric plant with the new Canadian government, reducing the power available

[General Pain]

The bridge would be the only remaining one crossing the Danube river and the only supply route for the Russian armies attacking Vienna - gone as in no chance in hell of replacing it. So basically is a suicide mission .... but nothing the characters can't handle!!

Ahhh...suicide missions...that's HQs GM-Style indeed.....strangly I can only remember one suicide in all my years of playing.

(the pc lost his arm....and asked for a gun on the operating table...bang!! - result: shocked players around the table)

[m47dragon]

If you ask a combat engineer, the answer will always be "Twice as much..."

Commonly referred to as the "Lotsa" method...as in "lotsa C4."

A series of cratering charges would make it impassable. Are you looking to delay forces, or cause permanent damage? Beware of "burning too many bridges behind you."

[Legbreaker]

The best result that could be hoped for against this particular bridge by an SF force would be to damage it beyond use. The team is simply unable to carry enough explosives to destroy the structure.
Cratering the roadway/decking is likely to be the best approach however some minor structural damage might be possible if detailed plans of the bridge were available before time and engineers were able to assess the best possible locations for the limited charges.

A team of say ten men is still likely to only inflict enough damage to render the bridge impassable for maybe a few days. This might however be enough time for NATO to prepare a new defensive line or inflict significant damage by artillery and airstrikes.

Sometimes delay is all that's needed....

[Cdnwolf]

Thanks all for the non-realistic -this is only a game - we aren't playing to do anything... you can remove the bug from my phones - information.

:D

[jester]

http://upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Jamestown_Bridge_demolition2.jpg/800px-Jamestown_Bridge_demolition2.jpg

This took 75 lbs or RDX and 350 shaped charges. Kinda beyond the scope of the mission but it is a pretty picture.


But, I see three different secontions falling in the photo. So, what if you just wanted to drop 1 section? That is all I propose, drop a wide enough section to make it beyond use.


Unless there is damn upriver where a esxplosives genious and a mountainclimber turned explorer can blow which will release a torrent of water that will take out the brigde. If that's the case then the problem is solved. :D

[Grimace]

Make sure you all wave to the nice FBI agents reading this page! :D

As far as taking down the bridge, your best bet would be to damage one of the main supports enough with all the explosives you can that it weakens the bridge. Then, like smokewolf suggested, you let the enemy run their convoy on to the bridge and let it collapse from the weight upon the weakened section. Thus topples the section of bridge while inflicting losses upon the enemy convoy.

You can plan all you want, but trying to run a covert op against a bridge like that, without having access to all of the nifty gadgets, gizmos and extractions equipment necessary for proper insertion and extraction will result in a big hairy mess that leave any major plans largely undone.

Make it quick, make it simple, and throw all your explosives at one major point in hopes of successfully weakening the main support structure of the bridge enough that weight and/or nature will bring it down. If you're real lucky, or have more explosives than I think you could probably, reasonably have in Twilight, then you might just be able to drop a section of the bridge right away. It won't be pretty, it won't be quiet, but if you just want something "blowed up", you throw enough explosives at it and it'll drop.

Oh, and it would also help out in a major way if you've got either a civil engineer or a very, very good combat engineer who can pinpoint the exact points, the minimal exact points, that would be best to plant the explosives to cause the greatest weakening effect on the bridge.

[Legbreaker]

While I agree that the supporting structure are the preferred elements to attack, I rather doubt anything much less than a truckload of explosives is going to do the job without may hours of preparation (boring holes, etc).
I would also be rather hesitant to plan for just damaging the bridge and hoping the weight of subsequent vehicles bring it down. Chances are that unless very lucky or the calculations and application of charges is spot on, not enough will be inflicted or the damage will be so great even a blind man would be able to spot how unsafe the structure is.
The aim really should be to drop as much of the bridge into the river as possible whilst leaving as little as possible for the following enemy engineers to work with. Ideally as has been previously mentioned, even starting repairs should need significant effort to simply clear the debris.
With only the explosives a small team of SF troops are able to carry (remembering they're probably already loaded down with 40+ kgs of weapons, ammo and other vital equipment) the best that could be hoped for is cratering of the decking, and damaging supporting beams. With luck/planning, some beams mad be dropped across the decking creating more work for the engineers (both clearing and ensuring the structure is still able to carry tanks, etc).
The more debris that can be created, even without significant damage to the structural components the better - more locations to place booby traps and anti-handling charges.
While obviously not ideal, slowing the enemy by causing them to spend time on the bridge may be enough.

Unfortunately one has to remember that modern armies possess a much greater ability to cross water obstacles than even just a few decades ago. Many armoured vehicles are either capable of swimming, or in the case of some heavier AFVs able to use snorkels. A dropped, or even badly damaged bridge may not hold up the enemy advance for long....

[Targan]

I still think my barge full of ANFO idea has merit.

[Legbreaker]

So do I. Unfortunately it's not the stealthiest of insertion methods and you still need to pack the charges on the structure...
Unless you're looking at several tonnes of it in VERY close proximity (any air gaps significantly degrade performance to the point where you might only shake the rust loose).

[jester]

YOU ARE WRONG!

Google the following guys,

"Col John Ripley" and "Bridges at Don Ha."

1 man, crawled carrying full combat harness and weapons and satchel charges under a reinforced bridge that could handle TANKs. And he was able to place several charges, enough to drop the spans destroying the bridge. So, it is possible, if one man is able to do it, than I think a team can manage it.

And then the idea of modern mech vehicles with their amphib capabilities.

Sure, the armored vehicles can cross, but who here has traversed water in a armored vehicle? <Marines forward!> its painfully slow, and thus you are an easy target for everything to include slingshots. But, that is not the only thing.

A mech vehicle requires a large support and supply chain. Once the mech amphib vehicles cross, how long can they operate? They'll need fuel, ammo, mechanics to service them, the crews will need food and rest, so how long can a mech force operate if they cross a river and are forced to operate without a supply train? That has been the thing that has doomed most massive military disasters in history! A poor or non existant supply line, it destroyed Napoleon in Russia, the Germans in Russia, the British in the US Revolution, the Americans in the Philipine Campaign and several others. They could not sustain themselves and soon withered and became combat ineffective. Granted, these are major campaigns and a small column of BMPs is a small action, but if they are cut off and do not have the chance for fuel or ammo resuply they will soon be a sitting target unable to withdraw and soon unable to defend themselves.

[Targan]

So do I. Unfortunately it's not the stealthiest of insertion methods and you still need to pack the charges on the structure...
Unless you're looking at several tonnes of it in VERY close proximity (any air gaps significantly degrade performance to the point where you might only shake the rust loose).
How about packing the front third of a barge with explosives, backing and topping that section with steel plate and other tamping and filling the rear third with ballast. Then either use the current to hold the barge against the pillar at water level or water proofing the explosives and scuttling the barge next to the footings?

[Legbreaker]

Hmm, could work....
I like the idea of sinking it and using the water to transmit the expplosive force into the pilings. Still a big, difficult job though...

As for the one man dropping the bridge, how well built was they? Was it a modern, highly engineered structure such as we're discussing here?
Or little more than logs or hastily contructed temporary spans (eg a bailey bridge)?

Just because somethings capable of supporting a WWII tank (not a lot of weight really compared to modern days AFVs) doesn't mean it's anything like a modern autobahn bridge intended to support maybe a hundred times that weight.

Yes, Col Ripley may have been exceedingly brave and pulled off a very difficult task, but I don't feel it's really comparable.

[Fusilier]

YOU ARE WRONG!

I would say that is still subjective to whatever bridge you are talking about. Not fact, and definitely not wrong to think its not probable considering the objective given.

So, it is possible, if one man is able to do it, than I think a team can manage it.

Again, it still depends on the bridge and a huge amount of other already mentioned factors. Its not a given that it'll be possible to drop it into the river just because of the amazing feat of said event. The bridge in Vietnam was only about a third the size. And was likely built using different bridge architecture styles (US seabees) that what you see in Europe along the major highways over one the largest rivers.

Another reason I think the Ripley example isn't comparable is that he didn't need stealthy deep behind the lines insertion. He had a bunch of marines providing cover fire since they were defending the bridge area, not sneaking in deep behind enemy lines. The saboteurs in this example will be probably dealing with an already dug in force on both sides and won't have the firepower to sufficiently cover a demo group. Therefore IMO its significantly much more difficult task.

amphib crossing is painfully slow, and thus you are an easy target for everything to include slingshots.

If its behind enemy lines, any amphib water crossing is probably not going to be coming under fire including that from slingshots. Since its the only bridge standing, for the Danube armies, it'll be already well defended. That further increases the problems for every extra man you attempt to get to the objective and work on it without being discovered.

For logistics, it only stands to reason with me, that an engineer unit would be deployed nearby with bridging/pontoon equipment if for only the reason you mentioned. The Serbs for example did this during the bombing campaigns a couple years ago. Bridge goes down, but a few hours later lighter traffic can cross. Bridges in North Vietnam is another example.

[Rainbow Six]

Before I viewed this thread I thought it was a follow up to the "Entertainment Pricing" thread...;)

[Cdnwolf]

I just had an idea... since the river substains a lot of barge and boat traffic including small river cruise ships... maybe grab a working ship... and ram the support pillars?

[pmulcahy11b]

I just had an idea... since the river substains a lot of barge and boat traffic including small river cruise ships... maybe grab a working ship... and ram the support pillars?

That is innovative. Maybe the ship itself can carry explosives that detonate on contact...or, if properly protected from the impact, the ship can carry an assault force instead of explosives.

[smokewolf]

I just had an idea... since the river substains a lot of barge and boat traffic including small river cruise ships... maybe grab a working ship... and ram the support pillars?

Most support pillars are reinforced concrete and steel. Don't think it would do much on it own.

From http://www.ens-newswire.com/ens/nov2007/2007-11-08-093.asp
"The collision damaged the 900-foot container carrier Cosco Busan, allowing 58,000 gallons of bunker fuel to spill into the bay. CALTRANS has confirmed there is no structural damage to the bridge."

If a 900' container ship loaded with 58k of fuel can't damage the supports I don't think a little barge is.


And one involving a barge...

From http://www.delmarvanow.com/article/20090708/ESN01/907080372/-1/ESN
The barge was towed away from the facility. After officials determined there was no damage to the northbound section, all traffic was diverted to those lanes just before 7 a.m.

Not to mention most modern bridges have barriers around the support pillars to protect them from debris and runaways.

[jester]

Colonel Ripley was a Marine advisor in Vietnam. He dropped the bridge at Dong Ha in 1972 Durring the Norths Easter Offensive. The bridge was a main link and major bridge as robust of the photos in the above pictures. It was the bridge on a highway that the Northern Forces were intent upon using to cross in a major offensive. This included a few hundred T-65 type tanks <hardly WWII class, closer to modern and what we would find in the T2K world.>

Ripley was one of two Americans assigned to a S. Vietnamese Bn who has exhausted their ammo but they had been given the order to "Hold and Die!"

Here is an exerp of the Colonels Obituary:

ANNAPOLIS, Md. — Retired Marine Col. John Ripley, who was credited with stopping a column of North Vietnamese tanks by blowing up a pair of bridges during the 1972 Easter Offensive of the Vietnam War, died at home at age 69, friends and relatives said Sunday.

Ripley's son, Stephen Ripley, said his father was found at his Annapolis home Saturday after missing a speaking engagement on Friday. The son said the cause of death had not been determined but it appeared his father died in his sleep.

In a videotaped interview with the U.S. Naval Institute for its Americans at War program, Ripley said he and about 600 South Vietnamese were ordered to "hold and die" against 20,000 North Vietnamese soldiers with about 200 tanks.

"I'll never forget that order, 'hold and die'," Ripley said. The only way to stop the enormous force with their tiny force was to destroy the bridge, he said.

"The idea that I would be able to even finish the job before the enemy got me was ludicrous," Ripley said. "When you know you're not going to make it, a wonderful thing happens: You stop being cluttered by the feeling that you're going to save your butt."

Ripley crawled under the bridge under heavy gunfire, rigging 500 pounds of explosives that brought the twins spans down, said John Miller, a former Marine adviser in Vietnam and the author of "The Bridge at Dong Ha," which details the battle.

Miller said the North Vietnamese advance was slowed considerably by Ripley.

"A lot of people think South Vietnam would have gone under in '72 had he not stopped them," Miller said.

Ray Madonna, president of the U.S. Naval Academy's 1962 graduating class, served in Vietnam as a Marine at the same time and said his classmate saved countless U.S. and South Vietnamese troops.

"They would have been wrecked" if the tanks had crossed, Madonna said. He said Ripley also coordinated naval gunfire that stopped the tanks from crossing at a shallower point downstream

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So, yes one man can do it. And the enemy were the ones who had the heavier weapons who could provide the supressing fire.

Now, with stealth, a team to do the work instead of one man, and luck, because if its behind enemy lines or in an area thought to be secure then it is possible it can be done.


Here is a link to an interview as well as a few pictures of the two bridges he took out:

http://www.youtube.com/watch?v=rdpQY_sCL7I


And here is a copy of his citation:

Navy Cross Citation, USMC Captain John W. Ripley, Advisor, 3rd Vietnamese Marine Corps Infantry Bn.

The Navy Cross is awarded to Captain John W. Ripley, United States Marine Corps, for extraordinary heroism on 2 April 1972 while serving as the Senior Marine Advisor to the Third Vietnamese Marine Corps Infantry Battalion in the Republic of Vietnam.

Upon receipt of a report that a rapidly moving, mechanized, North Vietnamese army force, estimated at reinforced divisional strength, was attacking south along Route #1, the Third Vietnamese Marine Infantry Battalion was positioned to defend a key village and the surrounding area.

It became imperative that a vital river bridge be destroyed if the overall security of the northern provinces of Military Region One was to be maintained.

Advancing to the bridge to personally supervise this most dangerous but vitally important assignment, Captain Ripley located a large amount of explosives which had been prepositioned there earlier, access to which was blocked by a chain-link fence.

In order to reposition the approximately 500 pounds of explosives, Captain Ripley was obliged to reach up and hand-walk along the beams while his body dangled beneath the bridge.

On five separate occasions, in the face of constant enemy fire, he moved to points along the bridge and, with the aid of another advisor who pushed the explosives to him, securely emplaced them.

He then detonated the charges and destroyed the bridge, thereby stopping the enemy assault.

By his heroic actions and extraordinary courage, Captain Ripley undoubtedly was instrumental in saving an untold number of lives. His inspiring efforts reflected great credit upon himself, the Marine Corps, and the United States Naval Service.

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And again, we it is possible. As was stated many factors do come into play. But, it is possible a small force can do the job quite handily.