Covered in A Bridge Too Far at Son.
“When you refer to Bailey crap I take it you mean that glorious, precision-made, British-built bridge which is the envy of the civilized world?”
Perhaps those tasked with rebuilding bridges can better appreciate why blowing up a bridge would only be resorted to when absolutely necessary.
Quite the racket. Smedley Butler would be equal parts impressed and mortified. First build the bridge. Then blow it up. Play your cards right and you can repeat.
This. I recently finished the official Army history of the Battle of the Bulge, and I remember the quoted passage. Not to mention that they didn’t expect the Germans to penetrate as deeply as they did.
You also want to blow the bridge in a way that it can’t be easily repaired by the enemy. That’s a little harder.
My dad got to remove explosives from the Leudendorf Bridge [Remagen] and his comment was that yes they did remove most of it, some did go boom, but what ended up destroying the damned thing was the trucks and tanks chugging across it. He got shifted from armored to engineers because of his aptitude with making or stopping things form going boom.
Nitpick: Hogan and Sister Sara.
This has already been somewhat covered by other posters, but I’d like to emphasise why this isn’t true and how it applies to a battlefield. To blow up a bridge, an army has to have the right explosives in the hands of the right people at the right place and at the right time. The people are going to be a unit, probably a platoon, of combat engineers whose orders come from brigade or division level. They will have a long list of tasks that the brigade/division commanders want accomplished, and aren’t going to be sitting around waiting to blow up a bridge. So when the decision is made to blow up the bridge, someone in operations needs to find out where the combat engineers are, order them to go to the bridge, and make sure they have transport to get to the bridge.
The explosives probably aren’t going to be with the unit of combat engineers. It’s not like they’re going to carrying around hundreds of pounds of explosives in the back of a truck just in case they need them. Instead, the explosives will probably at a depot. So someone, whether it’s an engineer, or someone in ordnance, is going to have to arrange to get the explosives to either the combat engineers unit or to the bridge.
Place isn’t going to be much of a problem. You can expect that an army will know the location of a bridge they’re fighting for or retreating across. However, getting from one place to another in a battlefield can be very problematic. There can be bad roads, blocked roads, one-way roads, and road networks that require moving away from the destination before moving towards it. And traffic. Because it won’t be just the combat engineers unit heading to the bridge. Supply trucks, reinforcements, ambulances, and units with other missions will all be headed to the area around the bridge. Meanwhile, other trucks/units will be moving away from the bridge.
As for timing, how much time would there be between when the need to blow up the bridge was recognised by senior commanders, to when the blow-up had to be executed? Something that may be easy to do in two days can be very difficult to do in one day and impossible to do in half a day. And, as other posters have noted, the bridge blower-uppers are likely to be working under enemy fire. Keeping one’s head down and trying not to die does tend to slow one down.
Having written all that, I didn’t recall that the Battle of the Bulge had a lot of German success at bridge crossing against determined opposition. I only watched a few minutes of the Youtube video you posted, but it mentioned the Battle of Trois Ponts. In that battle, the bridges were successfully blown up. Indeed, doing a bit of reading up on the Battle of the Bulge, when combat engineering units had time to deploy, they were mostly successful at defending bridge crossings. This is a rah-rah account of WW2 Battle of the Bulge Combat Engineers, but it contains a lot of factual information about the success of those defences (pdf).
I (perhaps naively) would think that as soon as the need to retreat across a river starts to look even remotely possible, it would be standard practice to plan for the timely destruction of bridges. Seems about as basic as planning to keep your soldiers supplied with ammunition.
There are fallbacks, retreats, and routs. If an army is moving back it’s forces to delay an enemy, aka a fallback, it has plenty of time for planning. If an army has suffered a defeat, or a consequential surprise, it may be organised and capable of performing a managed withdrawal, but it’s certainly not planned for, other than contingency plans. Contingency plans are going to be high-level and provide strategic guidance but not suitable for directing troop movements. A rout is an uncontrolled withdrawal.
My answer to the OP’s question is that the decision to blow up a bridge would be made by a senior commander, and would take time to implement. If caught by surprise, the commander’s desire to blow up the bridge would probably be hindered by the time to turn that desire into an operational plan that could be implemented.
For lots and lots of explosives, yes, the Engineers would need a trip to the depot. But recall my post upthread, EACH engineer, in addition to carrying a standard combat pack, is also lugging around 40 pounds of dynamite on his or her back. 40 pounds, put in the right places, can do great damage!
I discussed this very post with Mr VOW (the retired Sgt VOW, with the Combat Engineers MOS 12B). He started playing with his phone and found this on Wikipedia. Look up “M60 AVLB”
AVLP stands for Armored Vehicle Launch Bridge.
You gotta agree : that is so cool!
~VOW
After looking up the AVLB on Wikipedia, then go to youtube and look up M3 IRB.
IRB stands for “Improved Launch Bridge.”
~VOW
This says they may finally be getting around to rebuilding that Ludendorff bridge. No rails, though.
My dad blew stuff up during WWII, but not bridges. He was part of Underwater Demolition Team 11 (UDT-11) in the Pacific. They had the luxury of plenty of time for planning that the Army didn’t, but still had to work under enemy fire.
My mistake. I have seen 2MfSS a lot more often than I have seen TGTB&TU.
But they won’t call it the Ludendorff bridge again…
It’s been a couple of days, but I wanted to come back to this point. @Wrenching_Spanners makes the point that it’s a matter of planning and possibilities.
In war, as well as everything else, you simply can’t make all possible contingencies. Do you carry a three-day survival kit with your 24/7? Of course not, but it’s not feasible and the likelyhood is very remote.
Prior to the German counter-offensive, the Allies determined that the Germans have almost zero chances of a successful attack thorough the Ardennes, and the actual battle shows they their assement was correct.
The Allies made the mistake of assuming that because the chances were so slim that the Germans would be wiser to not waste their resourse on a doomed mission but rather the Germans would keep allocate the resoures on defense where it would do more good. However, they didn’t count on Hitler being Hitler.
That discussion is outside the scope of this thread, but not being ready to blow all the bridges was a reasonable risk for the situation.
I was a combat engineer in another life. 40 lbs of TNT (or C4 which for the purposes of this conversation has the approximately equal explosive strength) does not make as impressive an explosion as you would think. Destroying a bridge would take tremendous amount of explosives.
Does it matter what kind of bridge it is and how big it is?
Seems to me there is a difference between the Brooklyn Bridge and a one arch span over a stream.
Also (really asking), just how badly do you need to damage a bridge to make it unusable (to troops, trucks, tanks…)? Is annihilation the only thing or can a big hole in the middle cause problems?
(I remember some general saying during the Iraq war in the 90’s that they aimed for the ends of bridges and not the middle to make them unusable and hard to repair…old memory though).
I worked for several years with a former State bomb disposal officer. Following his retirement, he did quite a bit of training and blast mitigation consulting. As I recall, he often commented on the fact that it takes a lot more explosives than one might think to blow up a hard structure, especially if the explosives are not tamped. He was pretty dismissive of any quantity of explosives that a single person could carry. (This is obviously a much different situation compared to personnel injuries resulting from shrapnel.)