Dragonstriker

By having the capitalist Americans build all your factories and bureaus? Yeah, that is one way.

British procurement looking more like that of India every day , evil tongues could say of same folks running the show .

thank goodness we've gotten past all that and embraced robust, strong soviet policy which handily out-competed it.

Some detail on the hull faults on AJAX:

- inconsistent lengths
- hull sides not being parallel 
- substandard welding 
- etc 

Watching the mythology of Challenger 2 collapse finally after all these years has been deeply satisfying to me.

GDLS UK has announced that it will be providing verbal evidence to the Defence Select Committee on July 20. Also released ahead of the testimony is their written evidence: https://committees.parliament.uk/writtenevidence/37866/html/
 
At this rate my suspicion is that in short order, this will be the case because nobody sane will want anything to do with British cavalry scout vehicle programs after this.

or any other - even vapouware EOS types   Iron Fist just does not do what it says on the tin.

Dutch seem happy with it. 
 
Speaking of underperforming, here’s some pics of Lance 1.0.


 
 

 

 

 
First Australian Army turret conversion course. Pics: Private Jacob Hilton. 

CR2's failure should have shown Britain that their procurement was flawed. 
Nimrod's failure should have shown that.
Warrior failing officially but not Ajax should have sparked a lot of eyebrows being raised.
 
CR1's inadequate performance should have shown that.
 
What's Ajax gonna do? All the MoD is going to do now is to play victim like they always did and wait until the heat dies off and do it again.
 
They're dumb, and it's fun to watch.

This should really shake up UK procurement.

The idea that no modern tank can achieve protection across more than a limited frontal arc jives well with the fact that modern tanks do well when crewed by competent soldiers and die in droves when crewed by Saudis or Iraqis. If your magic armour only works from the front (and then only in certain spots) you need to be good at your job to stop people from flanking you.

I don't like your contribution. It's WoT Forums level shit, complete with bizarre white knighting for a tank.
The M1 isn't gonna let you fuck it, bro, no matter how hard you defend it on the Internet.

I don't think you're going to get a neat, single answer for all of this.  Penetration is very complicated even when you focus only on rigid OR eroding regimes.   APFSDS occupy a transitional region between those two, meaning it is likely to be even more complex. 
 
For example I did more digging by changing search parameters.  One thing I turned up came from army-guide and this interesting point:
 


 
Completely unsourced but it shows a the potential for multiple factors at work.    I've found sources that allude to nose shape influencing interface defeat, transitions from rigid to eroding penetration and velocity thresholds, and so on.  I'll share the various things I ran across in the hopes it will prove useful.  In no particular order:
 
CTH hydrocode predictions on the effect of rod nose-shape on the velocity at which tungsten alloy rods transition from rigid body to eroding penetrators when impacting thick aluminium targets
 
Abstract:


Design of hard-target penetrator nose geometry in the presence of high-speed, velocity-dependent friction, including the effects of mass loss and blunting
 
Abstract


 
INTERIOR AND TERMINAL BALLISTICS OF 25g LONG ROD PENETRATORS
 
Introduction:



Investigation of Oblique Penetration I: The Effects of Penetrator Leading End Shapes on Unyawed and Yawed Impacts
Abstract



TERMINAL BALLISTICS TEST AND ANALYSIS GUIDELINES FOR THE PENETRATION MECHANICS BRANCH
 
Introduction:


 
Penetration of 6061-T6511 aluminum targets by ogive-nosed VAR 4340 steel projectiles at oblique angles: experiments and simulations
Abstract



The Effect of Nose Shape in Long Rod Penetration
(link to free PDF download)
Abstract:


 
This one seems related to the one below, so I included it more for completion's sake and informative purposes. 
 
Comparative Study of Nose Profile Role in Long-Rod Penetration
Abstract:


 
Honestly I'm not sure this is very relevant.  It seems more about eroding-penetrator processes and mushrooming vs non-mushrooming.  But it's also about EM guns specifically, so it was worth mentioning.
 
Interface Defeat of Long-Rod Projectiles by Ceramic Armor
Abstract:


 
This is mostly about interface defeat in general vs ceramics, but there is a bit in there about nose shape.  So nose shape may be a factor here.
 
Interface defeat studies of long-rod projectile impacting on ceramic targets
 
Abstract:


 
Analysis of the Noneroding Penetration of Tungsten Alloy Long Rods Into Aluminum Targets
Abstract



 
This one seems to be more about rigid penetration, but its also about about LRPs. Worth noting for that 'transitional' aspect I mentioned and the fact nose shape has a huge impact in rigid penetration.
 
Modeling Threshold Velocity of Hemispherical and Ogival-Nose Tungsten-Alloy Penetrators Perforating Finite Aluminum Targets
Abstract

Ajax situation is ramping up. Trials have been suspended for a second time and Ministers now believe that senior officers hid the extent of problems so that it would not get cancelled during the integrated review.
 

Tricking Ministers will likely be Ajax's death knell.

I read this entire post, and the experimentalist in me feels victimized. 
 
Since you're in thermo (join the club), you should also know that carnot cycles for anything only give a dimensionless efficiency value designating the maximum energy transfer rates, ignoring all other variables, at a set temperature (or pressure if you get wonky). 
 
So, yes, a heavier bullet would, on paper, be more efficient with combustion. 
 
But that efficiency gain is peanuts when compared with what crimping does to a cartridge. The difference in projectile mass on a small arms scale is negligible thermodynamically given your scenario. 
 
Now, if you're putting together a potato cannon, we can get together and talk numbers. That's a much more interesting process, in terms of PdV etc etc. Plus it's something anyone can do!
 
I'm currently (in my off time that's not spent sending dirty pictures to Sturgeon) looking at building a PVC pipe gauss cannon. 

Crimping measurably increases efficiency, because it increases pressure. Because gun enthusiasts are typically backwards people, they consider this to be bad.

I agree with Xlucine's assessment that heavier bullets on top of the same propellant are more efficient - however once this is applied the advantages quickly shake out and you are compelled to bow before SCHV Zod.

Unless you're Emeric, then it's a suppression study

Is graceful like swan, but also asshole like goose.

Yeah, this is impossible. The closest you can approximate this is through pattern recognition software (which, incidentally, is how the postpross in your brain works), but that only works if there's a pattern to be followed.

If you are looking at a patch of sky at a certain resolution, a computer can simulate a higher resolution in a way that's convincing to a human being. What it can't do is show you details that are below the native resolution level, like far away or low signature aircraft, for example.

Maximum angular resolution is a function of beam width.  Beam width is a function of antenna size and operating wavelength.  An AESA might be able to wring a slightly smaller beam width out of a given antenna size and a given wavelength, but it is still subject to these same limitations.  It's fundamental physics; you see similar-looking equations if you look into the maximum focal range of laser weapons.
 
L band is an order of magnitude longer wavelength than X band.  Wing antennas are narrower than nose-mounted radars.  This supposed "wing mounted L band AESA radar" is going to have less than a tenth the resolution of the nose radar.
 
Computer signal processing do a much better job of finding useful signals.  A more capable computer can find information that a weaker computer would have to throw away as noise.  But there are information theoretic limits.  Computers cannot create information that they weren't given in the first place.  Computers aren't magical.  They cannot improve the resolution of a grainy photo to show the face of the killer reflected in a raindrop.

If a radar has a small antenna relative to its operating wavelength then its beam will be quite wide.  If there are two targets within that beam width at the same distance moving at the same speed then there is no possible way that the computer will be able to tell whether it's one target or two.  There simply is not enough information for the computer to dig through to find out what is going on.
 
Likewise, if a radar has a wide beam and it's engaging a moving target, it is going to have a hard time figuring out where exactly in this wide beam the returns are coming from.  It can move the beam around until it stops getting return signal, but the edge of a radar beam isn't a clean and abrupt end, and if the target is moving it won't be able to do this quickly enough to get a precise location anyway.
 
These are fundamental problems with the amount of information that the antenna can provide the computer.  The computer won't be able to fill in the blanks.

It's an Actively Electronically Scanned Array (AESA), but that does not mean it is a radar.  AESA is just a type of antenna, it doesn't necessarily mean it's a radar antenna.  It could be a transmit-only antenna, or a receive-only antenna.
 
It can't be a radar.  Or if it were, it would be the world's most singularly useless radar.  This isn't a matter of experience or design finesse, this is a matter of fundamental radar antenna physics.  That is not a large enough antenna relative to the wavelength it's operating in.

It is almost certainly an IFF system, but one that uses an AESA.
 
The way IFF works is that the aircraft with the IFF system gets pinged by a radar, and the radar sends a coded interrogation signal.  The aircraft that receives this signal sends back a coded response, which identifies it to friendly forces.
 
The problem with this for a stealthy jet is that the IFF system is broadcasting radio waves, which is decidedly un-stealthy and could allow any radar with a passive seeker mode to get a bearing fix on the aircraft.
 
The solution Sukhoi is using here is an AESA IFF system.  Instead of a regular antenna, the response IFF signals are transmitted through the AESA, which allows it to confine the signal to a very narrow beam.  AESA has extremely high gain and very small sidelobes, so it can make the IFF beam much narrower than a conventional antenna.  That makes it much less likely that an enemy eavesdropper will detect these signals and use them to locate the PAK-FA.

It is official, the PAK-FA is now the Su-50 Furry on SH.

Erm, lumping things like the P-59 and Schwalbe in with the F-86 seems decidedly silly to me.

The recoil length is 340 mm for the L/44 and L/55 guns with a hard stop at 380 mm. Only the L/47 LLR (light low-recoil) has a recoil length of 500 mm.