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California Tanker
1st February 2006, 21:23
Most modern AFVs have such a system. It usually involves spraying fuel directly onto the exhaust. The Abrams VEESS system has been disabled, however, since the change from the original turbine fuel to JP-8 which renders the system inoperable. A good demonstration of the British engine-created smoke system was on Top Gear when a Challenger 2 smoked out Clarkson's Range Rover. It affects almost exclusively the visual spectrum.

NTM

Bosco
2nd February 2006, 02:31
JP-8
NTM

Ye use AV-TUR in your tanks?
Bear in mind Im coming from an aero background so i'm a little shocked to see kerosene being put into vehicles that don't fly.

California Tanker
2nd February 2006, 06:28
Thanks Cal Tanker. I hope!
Maybe you can tell me. Why would an Abrams have external fuel tanks? I assume that they would only do so when not in a combat zone.


Because the things get about 4 gallons to the mile, and all the extra fuel you can get is useful. Most countries that use external fuel tanks attach large barrels to the back deck, such as the Soviets or British do. For whatever reason, possibly due to the engine heat, this isn't done for the Americans. Likely the American bladders carry more as well.

What they did come up with was this fuel bladder:

http://www.clubi.ie/exalted/images/Tanks/abramsfuel.jpg

Comes in varying different sizes. What you do is ditch the fuel bladder off the side, tie a hose to it, and then run over it, it will squish the fuel into the tank. Works fine for standard maneuver operations, such as the approach to Baghdad, but once the tanks started getting shot at, they lost the blivets very quickly.


Bear in mind Im coming from an aero background so i'm a little shocked to see kerosene being put into vehicles that don't fly.

Abrams uses a jet engine. As does T-80U and the now out-of-service Strv-103.
http://data.primeportal.net/iraq/packout.JPG

That said, all US Army vehicles, including trucks, run on JP-8. Used to be that the Abrams used JP-5, standard AvGas I believe, but they decided it made more sense to have a single fuel source. I guess JP-8 is the compromise.


That's nothing, I've seen an Abrams itself catch fire after the external fuel bladder was burst and the fuel ran into the engine!

Well, we had the exhaust from one Abrams blow another Abrams up!
http://data.primeportal.net/iraq/towfire1.JPG

So there!

NTM

Bosco
2nd February 2006, 12:20
Jesus the thing must be as quiet as a mouse, comparatively speaking compared to diesel engined tanks if it uses a turbine engine.

hptmurphy
2nd February 2006, 16:20
Multifuel engines have been around for years...even the Chieftan designed during the late fifties could run on Jet B...which is pretty fine cut. Tears the shite out of the engine ..but works fine.

Rememeber that all high compression fine cut fuels are only derivatives of diesel........you can run a tractor on JET A1...most home heating oil is produced from contaminated Jet fuel.....evry wonder where all the fuel samples go...or when tanks are emptied...recycled as home heating oil

California Tanker
2nd February 2006, 17:18
Jesus the thing must be as quiet as a mouse, comparatively speaking compared to diesel engined tanks if it uses a turbine engine.

You'll hear the tracks long before you'll hear the engine.

We actually got close enough to an Iraqi to bonk him on the head with the gun tube one day. We were creeping through traffic, mounted the center divide. He was standing on the divide, his attention completely fixed on something on the side of the road. We had initially thought he was deliberately ignoring and obstructing us until either he caught movement out of the corner of his eye, heard something, or just this little voice inside his head said 'look left'. He looked left, and I swear jumped a foot off the ground in shock before running across the road. We absolutely fell apart laughing inside the tank. We weren't the only ones, a lot of the pedestrians were laughing their asses off as well.

NTM

yooklid
2nd February 2006, 17:19
Couldn't the SU-25 fly on Diesel?

DeV
2nd February 2006, 21:01
The Alouette III can run on petrol or diesel (can't remember which) so long as it is mixed with parafin.

Bosco
2nd February 2006, 23:12
Just for refernece guys JP-5 is AV-TUR not AV-GAS, I know i'm nitpicking.
Av-GAS is for pistons and AV-TUR is for turbine engines.
Like I said I know i'm nit picking here but i'm pretty sure you would if I said something wrong about tanks or armoured stuff.
Anyway just after reading up it seems to have been a logs decision. Easier too transport one type of fuel than 2 or three different types.
Still though i'm impressed as AV-TUR is notoriously flammable when placed in confined space(safe as houses though when its not confined i've seen people drop a lit match into it and it doesn't catch fire, just quencehs the match, scared the shite out of me at hte time)

hptmurphy
3rd February 2006, 00:22
Av_tur is not combustible at all..in all its forms..will only burn above 21degrees c....under compression....AV gas..on the other hand will burn at minus 14 degress c... nad burns at a bout 400 feet per second..

Allouettes will run on Jet B...which is a mixture of Diesel and petrol...a 1960s fuel which is not generaly available out side the military...although the old Aer lingus Shorts 360s were labelled to be able to run on the same.....

And if any body wants to question my answers..please take it up with the CAA fire school in Teeside...

yellowjacket
3rd February 2006, 00:30
Still though i'm impressed as AV-TUR is notoriously flammable when placed in confined space

Can you elaborate a bit on that? Superficially it seems physically impossible, flammability ranges and all that lark.

Goldie fish
3rd February 2006, 00:40
And the IMO experts strike again....

Bosco
3rd February 2006, 01:14
Can you elaborate a bit on that? Superficially it seems physically impossible, flammability ranges and all that lark.

Like murf said under pressure i.e. confined space its what took that 747 down off of Long Island back a few years ago. Spark came in from outside wiring taht was bundled with the fuel probe wiring. This brough it the nitrogen topping off of fuel tanks( similar to INERGEN I think)

California Tanker
3rd February 2006, 02:19
Hang on, it was vapours, not fuel that blew up the TWA flight. It had some stupidly low level of fuel in the center tank, the spark set those off. And unless my physics is shot, vapours under high pressure become liquid.

NTM

strummer
3rd February 2006, 04:05
It's always vapors that burn. Solids do not burn, rather the vapors from the solids or liquids.

hptmurphy
3rd February 2006, 09:39
Correctemondo....look at fuel burning..its not the actual liquid but the vapours it gives off!

yellowjacket
3rd February 2006, 10:20
Yep, the tank was nearly empty and at lower atmospheric pressure due to altitide, thereby dragging the fuel vapour/air mixture just into the flammable range (usually theres not enough air in a fuel tank to get it to burn)

AS CalTank says, it's very very difficult to get a liquid under higher pressure to burn.

The Sultan
3rd February 2006, 10:51
It's always vapors that burn. Solids do not burn, rather the vapors from the solids or liquids.

Am I right to call that pyralisation? (Thats directed at yourself or YJ).

NB:Slightly off topic, but this is a pretty good thread

GoneToTheCanner
6th February 2006, 14:06
hi all
With regard to using Avtur/Jet A1 in diesels, one invariably ruins the injection pump in road vehicles if a lubricant is not mixed in with the Avtur. I've seen it happen on airfield vehicles more than once. I'm sure someone can elaborate about the lubricative properties of Avtur versus road diesel. Whilst aero turbines such as the Alouette's Artouste engine and the Short's PT-6 can burn diesel, if you're really stuck, the engines life is dramatically reduced (something to do with the resultant turbine temperature, I think). I don't imagine military multifuel diesels would last too long if you vary the fuel grade too much.... Although, I've used Avtur in older road diesels (mixed with ordinary diesel) without any problems...there is/was a variety of Avtur called AVCAT for aircraft carrier use, which had a much higher ignition temperature and was harder to accidentally light up than A-1. There was also a version called AVPIN used in jet turbine starter motors.....Anyone remember the SAAB Draken at Baldonnel years ago? They had to mix their fuel with oil, thru their ground service truck, before starting the engine, as the fuel was used to lubricate the pumps on the Avon engine, something I encountered on land-based industrial Avons...anorak mode selector to OFF.
regards
GttC