What would your Abrahams be without British armour? Hiw many Abrahams have been list? How many Chally's have been lost. Answer 1 to another Chally. End of argument.
As far as Norway is concerned, it looks like the future anti-aircraft battery/batteries of the Norwegian Army are going to consist of a mix of maneuver SHORAD (ACSV G5 with IRIS-T SL*) and NASAMS III with High Mobility Launchers. The latter has also been acquired by Australia in addition to cannister launchers, but theirs will be based on the Hawkei PMV instead of the HMMWV.
* I also would not be surprised if the SHORAD vehicle will also be outfitted with a H&K GMG and programmable ammunition similar to the C-UAS solution selected by Germany. In the latest image I've seen of this vehicle, it has both an RWS and a pintle mount FN MAG, and although the image is too small for me to be able to tell what sort of weapon is mounted in the RWS, I suspect it's a GMG since it seems a bit excessive for such a vehicle to carry 2 MGs (even if they are of different caliber).
If you weren't, we wouldn't have this discussion anymore. The point that the XM774 managed to defeat the BRL-1 special armor target claimed to be equivalent to the XM1 Abrams in 1978 should have been sufficient. Frankly any of the other sources should have been sufficient to make you question your own claims regarding the M1 Abrams' ability to protect against the XM774 round. Instead you have come up with other vague sources full of leaps of faiths and questionable assumptions...
That is the third time that you have claimed the XM1 supposedly was considered to provide protection equivalent to 350 mm steel armor (along a 60° frontal arc) and the third time you have failed to provide any source backing this claim up. Where is your source for this?
I've seen the 350 mm value four times, not once this can be considered a valid support for your claims:
S. Zaloga stated in his earlier books that the frontal armor of the M1 Abrams was equivalent to 350 mm steel armor. He did not specify an angle and has since started using Soviet estimates, showing that he apparently didn't have much faith in this value.
The Armor/Anti-Armor article published in the US infantrymen's magazine had a table in which the M1 Abrams front armor (again not frontal arc) was attributed with 350 mm steel-equivalent protection. The same table however claims the M60A1's frontal armor provides 325 mm protection vs KE rounds, which not only is inaccurate, but also shows us that this table isn't focused on a 60° protected frontal arc.
Jake Collins' now defunt wargaming reference collection of armor and penetration values, which unfortunately has been copied to dozens of web forums and still is used by ill-informed people, contained a value from Paul Lakowski attributing the M1 Abrams with 400 mm steel-equivalent protection based on a claimed 350 mm steel-equivalent protection along the frontal arc (which itself is a reference to Zaloga's original book). Paul L.'s old estimates have proven to be of extremely poor quality and he has since stated that his old estimates shouldn't be used due to inaccuracies
The 1982 (!) CIA document "Proposal for interagency intelligence memorandum on Soviet armor program" contains a paragraph that the CIA assumes that in the future a Soviet 125 mm APFSDS round will be capable of penetrating 350 mm steel armor at 2,100 meters range. There is no statement that the M1 Abrams would be able to resist such a round along the frontal arc, instead it is clearly stated that the M1 Abrams' development was started under the assumption the Soviet 115 mm APFSDS rounds could penetrate 147 mm of steel armor sloped at 60° at a distance of 1,000 meters.
I have provided you with four (!) sources of higher quality stating that the protected frontal protection of the M1 Abrams is focused on only a 50° arc, you have ignored that.
What you still massively fail to understand - aside of using an arbitrarly protection level of 350 mm along a 60° arc without having a source for it - is that RHA equivalent protection is not independent form the ammunition used. The 320-340 mm steel equivalent protection along a 50° arc (British assessment) or the 350 mm steel equivalent protection along a 60° arc (that you apparently pulled out of hot air) are achieved against the types of ammunition used to test the armor protection of the XM1 Abrams.
The XM579E4 APFSDS failed at defeating the XM1's armor at 1,000 meters distance, because it consisted of a high density early WHA alloy in a steel sheath. The penetrator core was very brittle and even simple spaced armor significantly affects its penetration ability. The XM774 was a monobloc DU penetrator, which is why it could defeat the XM1-equivalent BRL-1 armor target at ranges in excess of 4,000 meters (!) despite offering only 20 mm @ 60° more penetration.
Even with 394 to 427 mm steel equivalent protection against the XM579E4 and XM735 APFSDS rounds, the XM1 Abrams would not be protected against the XM774 APFSDS round. The same applies to the Leopard 2AV, which could stop the 105 mm K38 APFSDS round at 200 meters distance, yet was vulnerable to the monobloc 105 mm M111 Hetz APFSDS from distances as great as 2,000 meters.
Aside of the fact that it literally doesn't. Only after you apply your unproven, unsupported protection values that stand in direct conflict with proven, supported values, it becomes possible. I certianly wouldn't call that "reasonable".
Because it is a generic figure. It also is the exact same number as the XM579E4 and XM735 penetration, if you use a shorter distance to the target or change the angle of slope.
For "one version of the M1 turret armor" in a document that specifically calls about the possible need for improved protection and is from mid-1982, when the M1IP and M1A1 already existed as prototypes.
The CIA has underestimated the Soviet armor and penetration capabilities. That is a fact. The whole NATO did until the mid-1980s and that is absolutely relevant to the topic, as the armor of the M1 Abrams, Leopard 2 and also the Challenger 1 was designed to stop rounds that fell well below the Soviet capabilities. The protection requirement for the M1 Abrams was to stop the XM579E4 APFSDS round, as the US Army believed that to be well ahead of contemporary Soviet 115 mm APFSDS projectiles. This is a confirmed fact and not for debate. Meanwhile we have no source and no indication that the XM774 was ever used to test the armor protection of the M1 Abrams. We have however a US General telling congress that the BRL-1 special armor target provided the same amount of protection as the XM1's armor and we have declassified documents proving that the XM774 could defeat the same target in excess of 4,000 meters.
I do not have a negative attitude towards the US. Check this topic and read the older discussions; I have argued the same way against people attributing the Challenger 1, Leclerc, Leopard 2 and other tanks with way too much protection without providing any sort of relevant sources.
What I am doing - and you honestly also should start, if you actually had an interest in finding the truth - is the following:
I assess the competency of a source. A declassified document written for the staff of the FVRDE, the BRL or a meeting of high-ranking US Army members will contain more specific and more accurate information than a newspaper article written for Bob, Bill and Karen. Likewise Steven Zaloga's books have less competency as a source than R. P. Hunnicutts, just like Lobitz's books are less competent sources than Spielberger's.
When there is a conflict between different sources, I will pick the one with the highest competency rather than choosing the one that best fits my opinion/my ideal believe.
If a source is vague, I will I look at all possible interpretations for it, rather than chosing the one that best fits my opinion. I will look at the semantics and at other sources with similar or higher competency - if there is a contradiction or not.
If a source is vague, I will not use it to base my whole argument on it.
I've always considered myself as a younger member of the community, but the high influx of kids playing WoT, War Thunder and AW might have shifted that. So let me use this phrase: Back in my day, we learned this at school and university.
You on the other hand are an Abrams fanboy who doesn't bother to consider alternative interpretations, and considers newspapers more relevant than declassified documents as long as it fits your opinion.
If a CIA report says "one version of the Abrams turret", a fanboy's knee-jerk reaction is: "This means that the XM774 cannot penetrate the turret". Meanwhile my first question is: Why did they write "one version of"? How does this fit along with the other sources? What is the context of this statement?
The CIA document is dated 1982 and is specifically focused on possible improved anti-armor systems from the Soviet Union. What sense would it make to refer to the original Abrams in this context, when the improved M1IP/M1E1 already exist and would hence invalidate the need to discuss possible armor upgrades?
Using your logic, we could use old newspaper articles, Wikipedia and Zaloga's old books to argue that Chobham armor consists of ceramic tiles in a special honeycomb matrix structure... and this argument would be valid, because the fact that we have declassified documents saying otherwise is irrelevant.
Did you read what I wrote? The FSED prototypes were manufactured in 1978, the first on was handed over to the US Army in February 1978. One of the FSED prototypes was used for final ballistic testing in 1979.
We also know that the pre-FSEP Chrysler prototype had a weight of 58 tons, i.e. already was at the weight limit. As it is impossible that the FSED remained at the same weight as the earlier prototype, since it only added parts and increased armor coverage, Zycher and Morton have to refer to the FSED prototypes. They also stated that the design (with the 58 tons weight) was finalized in 1975, yet the FSED design was per R. P. Hunnicutt made in 1976. In other words: you are mistaken.
This is impossible, because the relation between the plates is wrong and the outside dimensions won't change that, hence you cannot get the proper plate thickness.Based on the fact that you are apparently overlooking the fact that the drawings from the Special Armor Secuirty Classification Guide only serve the purpose to illustrate the armor layout and are not blue prints or scale drawings, you are introducing massive flaws to your measurements/model and thus I cannot consider them in any shape or form valid for further discussions.
We have five confirmed measurements for the Abrams hull armor:
the upper glacis plate behind the special armor module
the upper glacis plate over the special armor module
the lower glacis plate
the back plate
the distance from outer edge to welding seam
Regardless how you scale according to outside dimensions, the relationship between thickness of the different plates remains wrong. The upper glacis plate above the special armor module and behind the upper glacis plate special armor module are both aligned on the same slope, so changing the outside dimension of the whole array won't fix that. The UFP behind the special armor cavity should be twice as thick as the UFP covering the special armor cavity as confirmed by measured values on the actual tank - but that's not the case. It is just ca. 50% bigger.
Likewise the frontal hull plate with a LOS thickness of 31.75 mm should fit 3.27 times into the back plate, if angles are adjusted. It fits however 3.5 - 3.6 times into the backplate. The UFP above the crew compartment (with 38.1 mm line of sight thickness) fits three full times into the 4 inch backplate, which also should not be possible. Regardless what plate I use to calculate the distance to the weld line, it never matches the measured value.
The relations between the armor plates are wrong. Scaling the whole image according to outside dimensions won't fix that. Given the inaccuracies between the plate thicknesses, assuming that any other dimensions and relations are accurate is silly.
This is wrong for two reasons:
First of all, you ignore the differences in angle. Changing the angle of impact from 25° to 20° increases the line-of-sight thickness by 24%. Changing the impact angle from 90° (i.e. hitting perpendicular to the turret armor module) to 65° (hitting directly from the front) increases line-of-sight thickness by only 10%.
Last but not least, until the late 1980s, APFSDS projectiles performed worse against steeply sloped armor, specifically against spaced armor arrays. So even if the frontal armor was 24% thicker, it wouldn't be guaranteed to provide the same amount of protection as the side armor against the XM774 APFSDS/simulated 115 mm APFSDS (DU).
If anything your argument has backfired and only shows that jugding by the reduction of the impact angle, until which the side armor can resist the XM774 APFSDS, the turret armor cannot withstand even a fr
This is again an example of you making an assumption, then making another assumption all in order to support your first unproven assumption. There is no statement that the new APFSDS round that can penetrate 15 inches of "armor" is the XM774 APFSDS. Aside of the fact that newspaper articles written by civilian journalists have a tendency to be inaccurate and full of sensationalism. Neither the XM735 nor the XM774 achieve a muzzle velocity of a mile per second.
The 15 inches of penetration is a generic figure and can mean anything given the wide range of unknown factors. Even the XM579E4 and XM735 can achieve 15 inches of penetration against steel armor under the right conditions. Furthermore the 15 inches figure appears to be a rough value given by a US official to the press, rather than an accurate value. "[T]he new armor" can as well be a generic statement in regards to Chobham or composite armor, rather than being a direct reference to the actual armor of the XM1 tank. The NYT article throws in several references to the - then in development - M1E1 tank.
The article also claims that the 105 mm gun with the then availablle ammunition would be sufficient to defeat Soviet tanks (it was not according to declassified CIA reports), the 120 mm gun would be overkill (it was not). It is not a reliable source, at least nowhere as reliable as the sources I have provided.
Yet this is nowhere directly stated.
They hadn't stopped underestimating the Soviets by the time the CIA document was written.
Yes, the armor was added to the FSED prototypes manufactured in 1978, which according to R. P. Hunnicutt served a reduction of weak spots rather than increasing the protection level against newer threats.
The improvements to protection included a new special armor gun shield compared to the previous one (made of cast steel only) and an increase in special armor module height in order to expose less roof area to the enemy.
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Your whole approach to the topic seems to be questionable. From my perspective you seem to have started with the opinion "the (X)M1 Abrams can survive the (X)M774 APFSDS" and then search for any sources that are vague enough that you can add your own interpretation.
"One version of the Abrams turret has protection equivalent to 400 mm RHA vs APFSDS rounds? That must be a reference (X)M1 and the (X)M774 APFSDS! An unspecified APFSDS round can penetrate 15 inches of armor at unspecified range and unspecified angle? That has to be a proof that the (X)M1 Abrams is protected agains that!" - yet we have much more detailed and clearer sources specifically stating that the Abrams in 1978 - the same year most of your "sources" (which are sources, just not for your claims) are from - was not protected agains the XM774 APFSDS round.
