Brewing Up...

[L4Pilot]

Any chance of having a round cook off occasionally inside a brewed up and burning AFV? For a future version or patch, perhaps>

[Guest Ol' Blood & Guts]

Huh??

A round cook off? What do you mean by that?

[TZEENCH]

Its when the crew sits by with marsh melows and hot dogs talking how the day went right?

[Juju]

I think L4 means unexploded rounds that go off later, caused by heat from fire or somesuch.

....Let's take cover behind that burning tank!!...

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Combat Axiom #49. It could be worse. It could be me.

[dalem]

OBG:

I think he means that the stored ammo would detonate/explode eventually as a vehicle burned. Without barrels and breeches to contain the force of the explosion the shells don't really go anywhere except maybe bouncing around the interior of the wrecked vehicle. From what I've read the secondary explosions could be pretty dramatic, and pretty *traumatic* if you were next to said burning wreck. But I've never seen it so don't know for sure.

Whether its do-able or not, I couldn't say, but I agree that it would look cool.

-dale

[Juju]

I have this old boardgame (Patton's best) that focuses on the Sherman. Whenever your tank got KO'd there would be a small change that the vehicle would brew up (especially if the tank did not have wet stowage). Removing wounded crewmembers was a harrowing experience (for a boardgame). You'd just never know if the thing would light up like a Ronson while you were rescuing your buddies.

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Combat Axiom #49. It could be worse. It could be me.

[Guest Username:]

Tanks in WWII had no real fire suppression for the crew areas. So a crews greatest enemy was a propellant fire NOT a gasoline or fuel fire. As the guns got bigger and the cartidges got longer, the amount of "powder in the keg" meant less and less time to get out uncooked.

The worst case scenario is a AP shell coming into your tank and causing a one of your HE shells to detonate. In the confines of the tank ALL the HE and propellent would sympathetically detonate. This would "grenade" the tank and rip its welds apart (followed by the fuel tanks igniting).

Some tanks used wet stowage (ammo is in boxes that have liquid around them) and manual extinguishers (yeah good luck). I have read of many cases where tankers bail out because they thought they had milliseconds to live only to recrew the vehicle and realize it was only a ricochet.

Lewis

Lewis

[Guest Ol' Blood & Guts]

Oh you mean, secondary explosions. OK, well hasn't this been discussed before, except I can't remember if any decision was made about this.

[Kurtz]

<BLOCKQUOTE>quote:</font><HR>Originally posted by TZEENCH:

Its when the crew sits by with marsh melows and hot dogs talking how the day went right?

<HR></BLOCKQUOTE>

And suddenly, one of the marshmallows catch fire.....

[Bullethead]

Lewis said:

<BLOCKQUOTE>quote:</font><HR>Tanks in WWII had no real fire suppression for the crew areas. So a crews greatest enemy was a propellant fire NOT a gasoline or fuel fire.<HR></BLOCKQUOTE>

I wasn't a tanker but I saw numerous tanks brew up in the Gulf. From this I formed the opinion that no fire extinguisher could do anything to help a propellant fire. Propellant burns to hot and way too fast for that. POOF and there's nothing of the crew but calcined teeth left. I believe this is why the M1 tank has blow-out panels on the turret roof over the ammo storage--the expanding hot gases vent through that instead of into the crew area.

I believe the WW2 wet stowage system helped by instantly soaking any exposed power from ruptured cartridges. This prevented a serious fire and the water also absorbed the heat from whatever burned before it could soak, although from fireman experience I imagine this resulted in steam burns for the crew.

As to cooking off ammo in general, the effect seems to depend on the type of vehicle. Propellant is a relatively low explosive and modern tanks don't have that many high explosive shells inside. So when they have ammunition problems, the result is usually an instantaneous pink fireball squiring out every seam as the propellant burns, followed by generalized burning of flammable contents. MG rounds can sometimes be heard popping inside and HE explosions are usually contained by the armor. However, sometimes there's enough HE aboard to blow the turret off. But HE is relatively hard to detonate so doesn't always go off even with a propellant fire. Still, I imagine riveted WW2 tanks could be blown to bits by HE secondaries.

HE is a terrible thing for thin-skinned vehicles such as SP guns, though. When it goes off, it totally wrecks the vehicle. I've seen them reduced to nothing but engine blocks sitting on the ground amid twisted fragments scattered over hundreds of meters. My webpage has some pics of Iraqi SP guns in various states of disassembly following secondaries.

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-Bullethead

jtweller@delphi.com

WW2 AFV Photos: people.delphi.com/jtweller/tanks/tanks.htm

[Guest Babra]

Was it water used for wet stowage, or glycol? (or something else...)

[Bullethead]

IIRC, the wet stowage used a water/glycol mix to keep it from freezing in cold weather.

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-Bullethead

jtweller@delphi.com

WW2 AFV Photos: people.delphi.com/jtweller/tanks/tanks.htm

[Mark IV]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Ol' Blood & Guts:

A round cook off? What do you mean by that?<HR></BLOCKQUOTE>

A cook-off is really when a chamber (rifle or tank gun) becomes so hot from firing, that a newly-inserted round fires from the heat alone, without the gunner pulling the trigger.

By extension it has come to mean any round that detonates due to ambient heat, i.e., your tank/vehicle/hall closet is on fire and stored ammo turns into fireworks.

Stored tank rounds and other ammo are designed for controlled expansion in a gun tube, and burn slower than bomb stuff.

In the open they are more like VERY large bottle rockets, than big bombs.

Not to be confused with a "hang-fire", where a normally-ignited primer (percussion or electric) causes a slow burn in a contaminated (water, oil-soaked, or poorly mixed) cartridge propellant. The gunner or loader decides the cartridge was a dud, and opens the breech to eject the round. Either then or shortly thereafter, the internal spark reaches a healthy section of the propellant charge and the round detonates in the open.

[Travis]

So, will it be modeled?

Travis

[Guest Scott Clinton]

no

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Please note: The above is solely the opinion of 'The Grumbling Grognard' and reflects no one else's views but his own.

[Bullethead]

Travis said:

<BLOCKQUOTE>quote:</font><HR>So, will it be modeled?<HR></BLOCKQUOTE>

In game terms, there'd be no effect in most cases. The only type of cook-off that would get out of the hull would be a big HE 2ndary explosion in a weakly built vehicle. Even thin-skinned SP guns remain basically intact from minor HE 2ndaries. And it's my experience that if the HE is going to go off, it's at the time of the hit and a propellant fire from ruptured cartridges. If that doesn't get it, it seems the vehicle can burn out completely afterwards (at much lower temperature) without an HE 2ndary. This can cook off MG rounds but those won't get out of the hull.

If you look closely at dead Shermans, sometimes you see their turrets knocked off their bearings. This is a good rendering of a small HE secondary. And that's about all the effect such a thing would have on any vehicle. So in that sense, cooking off is modeled

It would be interesting to model really violent HE 2ndaries in thin-skinned or riveted vehicles. Basically remove the vehicle model, replace it with an engine block and some pieces of the lower hull and running gear, and have a huge explosion mowing down all within a large radius. That would sure make you think twice about using your SP arty as assault guns

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-Bullethead

jtweller@delphi.com

WW2 AFV Photos: people.delphi.com/jtweller/tanks/tanks.htm

[Travis]

Thanks for the help, very good response.

Trav

[Supertanker]

The only game I can recall that included secondary explosions was M1 Tank Platoon 2, but they were just there for show. There were a few times that I had to doublecheck that an explosion was a secondary, and not one of my tanks being hit as we overran an enemy position.

[Guest Scott Clinton]

> The only game I can recall that included

> secondary explosions was M1 Tank Platoon 2

Well...CC3 had it (and I assume CC4 does also). Move a squad too close to a 'dead' AFV and risk losing men in secondary explosions.

IIRCC they seemed to happen WAY too often (every time?) and they were awful powerful too (IMO).

I am not saying CC3's method was 'better' or more 'realistic', just that CC3 tried to include them in the game. I am not sure that simply leaving them out of a game of CM's scale is not the most 'realistic' choice.

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Please note: The above is solely the opinion of 'The Grumbling Grognard' and reflects no one else's views but his own.

[This message has been edited by Scott Clinton (edited 05-24-2000).]

[Supertanker]

Whoops, I guess I should have said, "The only game I can recall of those that I have played." I gave up on CC after CC2.

It would be interesting to see secondaries modeled. Some of the "battle victim" pictures on that USSR WWII armor site show significant damage, probably from secondary explosions. I recall one JagdTiger (or JagdPanther?) that pretty much had lost its entire rear half. When a crew bails out from a burning vehicle, it would be interesting if you could pin them there and wait for the secondary. Maybe I'm just cruel.

[Runyan99]

I too would like to see cook-offs modeled, even if it only meant a graphical enhancement. Still, it seems to me that a tank cooking-off represents a minor danger to nearby infantry, and could be a factor in a scenario. CM has such an attention to detail, I expect to see everything modeled in the game eventually. Let's see it on the list for CM2, with a back-upgrade to CM.