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Collimatrix
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We all know Sparks is fond of advocating for continued upgrading of our M113s. I spotted this youtube comment the other day of an Iraq veteran giving his perspective on the matter: 

 

Upgraded%20Bradleys_zps8chy1mxn.jpg

 

"We had one run over an IED, it ripped a five foot hole in the floor, peeling it back like a banana."

 

Is he sure it was an IED and not just a stray AP round from a DShKM or KPV?

 

(Or maybe it just ran over an already fired projectile that scraped on the floor.)

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  • 3 months later...

I guess, if we eliminate the metric of being physically capable of destroying or making an effective kill against the other tank, the Sherman might be capable of competing against the Abrams. Probably need to remove any metrics relating to vision too. It's not fair to compare the two if we consider the Abrams' fire control so we're gonna take that out too. Yeah, sounds like a draw to me.

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I made an account only to comment and support that BRD is absolute retard. He is also a FURRY which is all you need to know to understand that he is absolute retard. ABSOLUTE FURRY RETARD. HOW THE FUCK ARE YOU GOING TO COMPARE SHERMAN WITH AN ABRAMS?

good first post, though you can compare the M4 to the Abrams but nobody with functioning cognition should come to his conclusion. 

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  • 3 years later...
On 7/16/2015 at 10:19 AM, Collimatrix said:

A wankel engine for a tank is attractive on paper; like I said, three companies have tried it (although none made it work).  Turbines have improved a lot since the AGT-1500 and GTD-1250 series, but I think a turbocharged wankel would still enjoy a bit of an edge in specific fuel consumption.

 

I have just discovered this hillarious thread thanks to Alex bringing it back to live after four years. The discussion about Wankels is particularly interesting though. AFAIK not even those experimental Wankel diesels were able to produce reasonably more power than they consumed. Aside of other issues common to all Wankels the diesel one has another much bigger ones related to the chamber shape (it was partially mentioned here already). The first is that from its principle it can not achieve high enough compression ratio to work at all, i.e. it needs to be fed by a compressed air to even run. So you need either sort of two-stage Wankel where one works as a compressor or you need an external supercharger. The other is that the chamber shape is absolutely wrong for diesel (there is no solution for proper injectior position and therefore also the mixture formation) and you can't do anything about it. Both things combined mean that the efficiency of such engine is abysmal and at least in some of the experiemental engines it was in negative values. And now all the other issues of the Wankel design on top of that... 

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2 hours ago, Beer said:

 

I have just discovered this hillarious thread thanks to Alex bringing it back to live after four years. The discussion about Wankels is particularly interesting though. AFAIK not even those experimental Wankel diesels were able to produce reasonably more power than they consumed. Aside of other issues common to all Wankels the diesel one has another much bigger ones related to the chamber shape (it was partially mentioned here already). The first is that from its principle it can not achieve high enough compression ratio to work at all, i.e. it needs to be fed by a compressed air to even run. So you need either sort of two-stage Wankel where one works as a compressor or you need an external supercharger. The other is that the chamber shape is absolutely wrong for diesel (there is no solution for proper injectior position and therefore also the mixture formation) and you can't do anything about it. Both things combined mean that the efficiency of such engine is abysmal and at least in some of the experiemental engines it was in negative values. And now all the other issues of the Wankel design on top of that... 



FWIW, the Rolls Royce Wankel Diesel was actually built.
 



There were, as I mentioned, a few others.

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17 hours ago, Collimatrix said:

FWIW, the Rolls Royce Wankel Diesel was actually built.

 

There were, as I mentioned, a few others.

 

Yes, I know. Though the Curtiss Wright one was not a real diesel. It burned diesel but it used spark ignition. 

 

Anyway, You are right, this last RR prototype looks to be really functional one (though the actual fuel consumption, reliability and durability is questionable as it looks like no testing was ever done or at least there is no info about it available). I learned that the development in Rolls Royce was stopped when the company went bankrupt and was briefly restarted when it was nationalized but soon again stopped. One can only guess that there was a reason why they didn't continue. 

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