Strykers aren’t immune to roll-overs

Okay, I’m always quick to point out when Stryker critics were wrong (which seems to have been quite often), but it’s only fair to play that way if you also point out events which support their case. One of the common criticisms was that the Stryker design was too top-heavy. A member of the 4-14 CAV, part of the 172nd Brigade, was killed Friday when his Stryker rolled. There are no details available, but the Army says that the convoy the Stryker was part of was not attacked. The accident occurred in Qadisiyah, which is near Rawah in the Euphrates valley not too far east of Syria.

More details here.

This isn’t the first Stryker roll-over we’ve heard about, though I’d like to remind critics that the two Strykers from the first brigade that fell into the canal didn’t just roll in. The embankment they were on collapsed. Too often critics point to those incidents as proof of the rollover problem.

UPDATE: POGO has a post up on this, and they predictably take a more critical stance. At least they point out that the roll-over problem isn’t limited to just Strykers, and they note this:

“Unfortunately, one of the best methods for avoiding IEDs (roadside bombs) is to drive like a bat out of hell and swerve a lot,” one insider told us. “This throws off the timing of the guys (insurgents) who are trying to either remotely or hard wire detonate an IED. Most of the time, their timing is too slow and the blast misses the vehicle.

“The down-side to this is there are a tremendous number of vehicle accidents associated with hyped-up young soldiers doing this day after day with Strykers, trucks and especially HMMWVs. All it takes is one mistake, and if you look at the number of nonhostile vehicle deaths due to accidents (again mostly in HMMWVs) you can see this unfortunate fact.”

They then immediately follow-up with a “yes, but”:

This may be true, but the Strykers appear to be a special case in at least one way. Because rocket-propelled grenades are a major threat, the Strykers in Iraq were outfitted with an add-on, 5,000-pound “slat” armor. This bird-cage armor increases the vehicle’s profile, and changes the vehicle’s handling characteristics.

So I’ll follow-up with my own “yes, but”.

Yes, the slat armor changes things, and the training wasn’t initially up to snuff. But the slat armor protects the Stryker very well against rocket propelled grenades, a weapon that the vehicle was not designed to withstand. I think the men in the Strykers will take the slat armor any day.

The final paragraph is interesting:

A story in today’s Aerospace Daily & Defense Report (paid subscription req’d) quoted a general saying that earlier rollover problems with the Stryker had been solved with more soldier training. However, even the extra training is a band-aid solution. The real fix will come when the manufacturer delivers vehicles with effective armor that doesn’t require the add-on cages. [emphasis mine]

This implies that the manufacturer delivered vehicles with ineffective armor and that’s why the add-on cages are required. That’s not the case.

Yes, there were some initial problems with the Stryker’s base armor, but that has nothing to do with the need for slat armor. The basic steel hull of the Stryker is designed to protect against 7.62mm fire. Ceramic add-on armor (which is where the problem noted earlier was) increases the protection to be proof against 14.5mm fire and 152mm artillery air bursts. The angled hull of the Stryker is designed in part to help deflect RPG fire, but the design spec didn’t call for RPG-proof protection.

This was known to be a potential problem, as any bad guy worth his salt has an RPG launcher and a cache of ammunition, so the Army designed the slat armor to be the short-term solution until reactive armor (which will also weigh down the vehicle, though not as much) is developed and produced.

So while improved armor will certainly be welcome when it’s available, it’s not accurate to suggest that the current slat armor is needed because of a design failure or a poorly-built vehicle.


  1. Yeah, to defeat a shaped charge without a ridiculous amount of armour (a la M1 Abrams) you need to create a stand-off distance for the warhead. That’s what the slat armour does. As I think you pointed out, there was a (quite clever IMO) proposal to fit slats to the rear of an M1 since its armour is thin back there (necessary to keep the weight reasonable) and the engine is vulnerable otherwise. ERA works slightly differently, but disrupting the penetrator jet, but has a similar effect, that is the penetrator jet is significantly weakened by the time it hits the actual armour and can not penetrate. It may be lighter but it can also be a hazard to infantry standing next to the vehicle when the RPG hits I think, which is obviously a concern for an APC. Still, those RPG cages on the Strykers look pretty awkward. But you’re right, nobody in their right mind would want to take them off…

  2. Murdoc – In general your statements are correct. The original version did not have RPG protection. The original specs called for a series of block improvements with the block 3 upgrades to have RPG protection. In theory the block 3 upgrades were supposed to go online in the 05-06 time frame. This did not happen as per usual upgrade timelines. The issue I have is the variance between the proposed mission of the stryker and the inability for the vehical to actually do that role. If however you want a light armored vehical to protect against small arms fire, its a great machine. In fact it details a pressing need, the need for a utility vehical that can be armored without compromising its utility function. In that case, you design your units around it and incorporate a mixture of vehicals to perform their roles. The issue I have, is that if you upgrade the armor to 14.5 or incorporate its RPG protection armor – the vehical is unable to full fill its prime reason of being. A easily transported armored vehical that allows for rapid insertion of military forces with a relatively small logistical footprint. So my bottomline point is, we spent 8 billion dollars for a vehical that does not provide a cost effective improvement over existing vehicals to operate in the light armor role and the stryker cannot perform the role for which it was created. All that aside, its a fine vehical, but is it the cats meow? Nah, any number of existing vehicals have superior abilities to the Stryker. A quick review of some M113 variants come to mind, as does South African and Austrialian transports.

  3. 12.7mm=.50cal Murdoc. 14.5=larger, LOL! GEts back to the old saw of why design a Strykers that’s light enough to be tranportable but not heavy enough to withstand the weapons likely to be used against it; then requires additional armor to survive, but screws up it’s handling, drive train durability, and transportability? Beats me? Are we sure the thousands of M113s we had in inventory wouldn’t have been cheper to upgrade, quicker to have procured, and just as transportable? I think so. On the other hand there just isn’t a vehicle that can’t be destroyed by ‘some’ munition or weapon.

  4. The Stryker is clearly a flawed vehicle. The M113 is old, and built of flammable aluminum. I think its time to throw in the towel and build a whole new vehicle, like a hover tank. Seriously, though, *every* vehicle is flawed. Like Flanker said, there’s always some munition that can destroy anything. And every vehicle is the result of a tradeoff between protection, mobility and cost. (Pick two) A lot of the critics of the Stryker miss that point with depressing regularity. And even if the Stryker was originally intended to be a lightweight air transportable APC, if it’s doing this job adequately, then that’s okay. There are more than enough military programs that cost more and couldn’t be used for anything at all. Way I see it, as long as the stryker is less expensive and lighter than a Bradley, there will be use for it, and it will be a valuable vehicle for the inventory. The spectrum between hummer, stryker, and bradley needs vehicles in all three places. (and maybe more.) The real problem is that there is a similar spectrum for pure gunned vehicles, and it doesn’t have the same coverage. All we have is the M1. A lighter offensive weapon would be real handy – something reasonably well armored, with some speed and punch. Like, I don’t know, the M8 AGS. Or at least something like it.

  5. Buckethead – For the most part I agree with you. We flushed 6.1 billion down a rat hole with the Comanche, so spending 10 billion on the Stryker is a bargin in comparision. So at this point, carping on the Stryker is a day late and a dollar short. It works well enough and has a role to play. With respect to your M1 issue. There is a need for some specialized offensive armor out there. A urban combat Tank is clearly needed. The M1 is built for long range combat. Something in the 40 ton class with lots of ammo, easy resupply, communications, and sensors with wide fire arcs from multiple weapon systems.

  6. As for an urban combat Tank… seems to me the best approach would be to work with the Israelis. I don’t think it will be light. The Merkava is probably the heaviest operational tank ever. The reason is that in an urban environment you can’t always rely on your threats coming from the front so you need reasonable armour all-round. They also do funky stuff like have mortars that can be fired from inside the tank, and machine-guns everywhere. Seems to me a collaboration between the US and Israel could produce a great vehicle which both could use, and would save both effort duplicating development (e.g. US has advanced armour technology, Israel knows what is needed for a good UCT).

  7. This is just a cut and paste job from what I posted over at POGO. Bottomline, the slat armor isn’t the cause of the rollovers, it’s the terrain, enemy, and training. 1. The slat armor to my knowledge hasn’t been pinpointed as a source of the Stryker rollovers ( However, I’m not going to pay for the Aerospace Daily article, and maybe it has specific information that subsequent rollovers have been correlated to the slat armor. 2. Training is a huge factor and not just a ‘band-aid’ solution. A driver must understand his limits when driving the vehicle, and exceeding limits results in consequences. For example, there were a rash of rollovers during the first three months of this year, nearly all involving the M1114 Up-Armored HMMWV. What was most striking to me was the fact that the HMMWV is a very stable platform due to its very wide wheel base, and while you add several thousand pounds to the HMMWV in making it a M1114, the fact that the trend occured at the beginning of the rotation for units indicates a training problem to me( Also, vehicle occupants also need to know what to do to protect themselves in the event of a rollover – this obvious doesn’t change whether a vehicle rolls or not, but it does reduce the chance of serious injuries and/or death in the event of a rollover. 3. Furthermore, you cannot discount the terrain as a factor. We are operating in the Tigris and Eurphrates River Valleys throughout Iraq, meaning we are navigating irrigation canal roads and other raised roads that reduce your margin for error – in otherwords, you pay for poor driving unlike if you were operating on improved, paved, four-lane roads. When we are operating away from these river valleys, we are typically using unimproved roads that may be built up, once again increasing the penalty for poor driving. Also, the Iraqis are terrible drivers. One of the fatal rollovers with the Stryker involved swerving away from an Iraqi vehicle to avoid a crash while driving at a high rate of speed. Whether the driver wasn’t experienced enough or failed to implement his training, I don’t know, but the fact is that you can’t swerve that quickly at a high rate of speed, and he should have chosen the lesser of two evils and hit the Iraqi vehicle that was on the same side of the road. A 20 ton vehicle will win that battle, although you will still have some injuries. 4. Next, the ERA tiles that can replace the slat armor will actually add additional weight and won’t significantly change the center of balance of vehicle, if it does at all, in comparison to the vehicle with slat armor. So, if the CB of the vehicle with slat armor is the issue (it isn’t), then it follows that ERA would still be an issue, and so your proposed solution wouldn’t really be a solution. Fortunately, what I’ve seen points to training, terrain, and enemy as being the factors contributing to rollovers. 5. Finally, I don’t know why you would swerve when driving as the ‘insider’ proposes. That certainly wasn’t an officially published technique nor one that I heard or saw unofficially while in country or since I’ve redeployed. Maybe his unit or vehicle crew adopted it, but it makes no sense to me, and in fact, contradicts the offically published techniques, tactics, and procedures that are taught during pre-deployment training, in Kuwait, and preached by the IED Task Force in Iraq as they travel around to the various commands.

  8. We already have a better machine than Stryker, and it is what Israel uses very effectively in urban combat. It can swim, crush obstacles that stop wheeled vehicles cold (for that matter, it can crush wheeled vehicles!), is much lighter than Stryker, and a better fighting platform. ‘even if the Stryker was originally intended to be a lightweight air transportable APC, if it’s doing this job adequately, then that’s okay.’ Do your research. Stryker is far less airmobile than the M113, and barely fits in a C130 which is our tactical airlift backbone. Unlike Stryker, M113s don’t tip when fitted with predet cages/’slat armor’.