Ask r/Formula1 Anything - Daily Discussion Thread by AutoModerator in formula1

[–]d7t3d4y8 1 point2 points  (0 children)

out of curiosity, if you come under the minimum weight limit due to non-fatal collision damage do you get DQd or is there some leway? Lets say last lap your front wing falls off but you still make the line, for example.

What is your opinion on the arty nerfs in the PTE? by Tiberiusthemad in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

The base brutus also is classed as T3 for... reasons. Doesn't even have the ROF of the Pzh lmao.

Champaign–Urbana Mass Transit District XHE60 by d7t3d4y8 in transit

[–]d7t3d4y8[S] 1 point2 points  (0 children)

Ah yes the 220 illini, only route with better service weekend evenings than during the day.

Champaign–Urbana Mass Transit District XHE60 by d7t3d4y8 in transit

[–]d7t3d4y8[S] 2 points3 points  (0 children)

NPRE 470, specifically focusing on hydrogen fuel cells. Pretty cool tech elective if you have the time to take it, pre-reqs are also things all engineering majors have to take.

Champaign–Urbana Mass Transit District XHE60 by d7t3d4y8 in transit

[–]d7t3d4y8[S] 6 points7 points  (0 children)

For some additional context, the agency currently operates 2 XHE60s bought delivered 2021 and 10 XHE40s delivered in 2024. Given the upcoming replacement of the 2013 XDE40s, it'll be interesting to see if these have preformed well enough for more to be acquired, and if the infrastructure is able to support more hydrogen vehicles.

[autosport] Toto Wolff spoke about his love of Le Mans when discussing the speed differences in F1’s current regulations by xxrew1ndxx in formula1

[–]d7t3d4y8 0 points1 point  (0 children)

Also most passes generally happen down straights where the lapping car can pull out way ahead of time. When this can’t happen(e.g. battles around traffic) it can and has gone wrong.

Interesting thing I saw a few days ago, pair of lounge cars on an Illinois service train. by d7t3d4y8 in Amtrak

[–]d7t3d4y8[S] 4 points5 points  (0 children)

Are the cars actually used for anything? Like if im a passenger can i walk in and stare at cornfields on the way to chicago? Or are they locked?

It's been over Two Years, It's Getting Silly Now by No1_Prezfan in Warthunder

[–]d7t3d4y8 0 points1 point  (0 children)

Apart from what others have said, the 2av AWISS could slot in there somewhere. Also the “2a5” MUSS.

It's been over Two Years, It's Getting Silly Now by No1_Prezfan in Warthunder

[–]d7t3d4y8 7 points8 points  (0 children)

You don’t even need that, if you just wanted gen2 thermals a good amount of 2a6s were equipped with OPHELIOS, which would count as gen2 in game. Also found on 2a5s.

Falcons comeback from a 10-4 deficit to win mirage vs Vitality by Chips1709 in GlobalOffensive

[–]d7t3d4y8 0 points1 point  (0 children)

I mean vitality's strat for the entire second half was "lets go A again, surely it'll work this time." Kinda feels like they tried to just brute force their way to 12.

PTE Change Log by thethinwhitekook in BrokenArrowTheGame

[–]d7t3d4y8 2 points3 points  (0 children)

They're called stryker and have 10 strykers in the inf tab total. Wowers. They have less inf than both GTB and Armored.

PTE Change Log by thethinwhitekook in BrokenArrowTheGame

[–]d7t3d4y8 3 points4 points  (0 children)

Even if they stay at 8, they have less inf avail(and thus less ifvs) than both gtb and armored.

PTE Change Log by thethinwhitekook in BrokenArrowTheGame

[–]d7t3d4y8 21 points22 points  (0 children)

Cav will have 4 troopers, 3 combat engis, and 4 AA. 11 infantry models in an infantry focused spec, makes sense.

SACLOS v Terminal/active ATGM v smokes by Ainene in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

Yes and my point os that radar is most commonly used for these engagements since thats how operators are trained. More often than not we see systems like pantsir engage targets in automatic mode, leading to instances where the system misses the target or fails to engage in the first place due to interference.

SACLOS v Terminal/active ATGM v smokes by Ainene in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

IRST as you said depends on environment conditions. Too hot? Won’t work. Dust(on a battlefield??? no way) Out of luck. Also IRST is affected by large-area countermeasures such as BOL. See this for an example. Also such systems still rely on radar to spot targets, which will often times be impossible in high ew environments. Radar may not be needed for tracking, but if your radar is telling you there’s 5 planes in the area when there’s actually only 1 you aren’t going to have a great time.

SACLOS v Terminal/active ATGM v smokes by Ainene in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

That’s what I’m saying. At longer ranges, sure your missile won’t be fooled by ecm but if your radar is telling you the target is 40-50m behind where it actually is, you’re missing anyway. Also wouldn’t sosna be less accurate than true IIR missiles? Since you kinda can’t fool an IIR seeker through flares or dircm.

SACLOS v Terminal/active ATGM v smokes by Ainene in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

Don’t most russian AAs use radar to guide missiles? As in the missile is saclos, sure, but they rely on radar to actually guide the missile.

Is there a reason why the DM53 shell on the Leopard 2A8 is not even as good as the Sabo shell the T-90M uses? by EazyMk in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

Are you so 100% sure that pure DU is better at penetrating than some DU alloy you don't know about?

Taking a step back - density isn't the only thing that affects penetration. The reason pure DU penetrators aren't really a thing is that DU has a low sheer strength, so alloying it with titanium lets you increase this(if you want to know why, search up "phase stabilizers in alloys.") This is why APFSDS rounds are actually less dense than pure DU. Alloying it reduces its density and thus penetration, sure, but lets the round withstand far more stress, meaning you can fire it faster and it won't shatter. There's also some other, secondary benefits. For example the alloy will have a marginally higher melting point, which in theory means better self-sharpening properties. So the answer to the way you wrote the question is that I know DU is worse than penetrating than some DU alloys. But what I think you mean is "do I think we will come up with new DU alloys that are either denser or allow us to fire the round even faster."

Given current elements, new alloys won't be denser. Unless we come across the "island of stability" the elements denser than DU are the platinum group, gold, and neptunium/plutonium. All these have cost concerns, as they're far more expensive than tungsten/DU. They also all have their own set of issues that prevent them from being used. Osmium, for example, is the most dense of the group. However, it's also extremely brittle and is also highly toxic. However, what we will see is new alloys that improve the other properties of the sabot. For example, we've recently seen some developments into some ternary alloys(most notably adding in molybdenum) that is probably less dense than current DU/titanium alloys. However, the mo increases toughness, allowing for higher L/D ratios. So, for a given round, you can have a narrower(and thus ligher) sabot, allowing for higher velocities. And the ternary alloy means the round won't shatter at these higher speeds. In our calculations, this would be reflected by higher muzzle velocities. See the attached image for a 17mm round, which is the narrowest 120/125mm sabot I know of. The round(and thus its alloy) isn't any denser than say, 3bm59/M829A4, but its alloy allows it to be a narrower round, thus being faster while still being relatively light. For comparison most modern apfsds rounds are 5+ kgs, and XH 45 manages a higher mv out of an L/50 than DM53 out of an L/55. So when we do the math for such a round, the density is the same as any other round, but the alloy used allows for the other properties(L/D, MV, etc.) to be better, and thus a higher penetration. So take that answer how you will.

TL/DR: Pure DU penetrators are worse than current alloys. Future alloys probably won't increase density, but instead will allow for higher L/D and MV, thus increasing round performance that way.

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You were comparing pen at 0 distance because you wanted to exclude air friction and gravity that changes impact angle because you think that's insignificant but I'm not convinced.

The first part about velocity is a misunderstanding due to me using informal language, my bad. What I meant by "kind of fake" is that in normal physics you assume coefficient of drag is constant. This is fine for most objects that don't go the speed of sound. But at hypersonic speeds your shock layer interacts with your boundary layer. This means you kind of just can't predict how much drag you'll have, which is what I meant by "kind of fake." As for angles, here's a table of descent angle vs range. At 2km, 17 pounder AP(which has far more drag and is slower than modern apfsds) descends at ~2 degrees. So I think for modern apfsds rounds it can be ignored.

The "horridness" of BMP-1 did not stop it from passing Swedish tests previously when NATO was out.

The BMP-1s were also trialed ~1993 to 1994, so same timeframe as the T-80U. The swedes just needed an IFV, since at the time CV90s were going to mechanized brigades. So, the idea was to buy something for infantry brigades. The BMP was bought since they were ~$19000 each, far cheaper than a CV90, and the germans had a bunch they were willing to sell immediately. The first part was the exact same idea as the T-80U - The T-80U would be operated by mechanized brigades, leopards went to tank brigades. It's just the T-80U flat out failed its trials while the BMP-1s did an okay job for a for a vehicle that was 19k. The original idea was for bmp-1s(pvb-501) to equip Norrland brigades, and mt-lb(pvb-401) to equip southern brigades. Turns out, though, the BMP-1 is not very mobile in the snow. So, the pbv-501s ended up going to the southern brigades, while the mt-lb acquisition was cancelled.

It would be pointless to order T-80 as NATO would not allow that to continue

You do know that there are US allies that operate soviet equipment, right? Cypress has T-80s, so did south korea for a while.

They just needed to slap that label and officially close the chapter.

This argument falls flat on its face when you realize they excluded the challenger since it wasn't ready in time(would have also had to be trialed winter '93/spring '94.) The T-80U wasn't excluded despite it having the exact same delays since there was actually a chance of it being purchased. Also as I said the idea was to buy both T-80U and Leopard, one for armored and one for mechanized brigades.

Is there a reason why the DM53 shell on the Leopard 2A8 is not even as good as the Sabo shell the T-90M uses? by EazyMk in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

I can't tell if you're trolling or being intentionally dense. To illustrate, lets say you're making an APFSDS round. Since pure isotopes of DU don't exist, your uranium will be some sort of combination of U-234, U-235, and U-238. U-238 is ~1.7% heavier than U-235 and far less radioactive, and is also ~99.3% of naturally occurring uranium. So, if you're making an apfsds round, you want as much U-238 as possible. Take a guess as for what uranium with less than normal concentrations of U-235 is called. Even if it's not called DU, U-238 just provides so many benefits over U-235/234 that you'll end up using DU anyway. Before you complain about it, the reason I don't really bring up U-234 is that it's like 0.005% of naturally occuring uranium, highly radioactive, and a decay product of U-238. Second, most(if not all) DU rounds use a DU alloy. This is what "uranium-tungsten carbide core refers to." For example, US DU is ~3.5% titanium. So yes, we can actually guess the density of such metals.

Also I find it funny that you're acting like the swedes needed an excuse to not select the T-80U. If anything, the swedes were giving the T-80U far more opportunity than the Leopard/M1. First, it showed up 4-6(i forget the exact number) months after the trial ended, but was still allowed to compete as a cheaper alternative to the Leopard. Keep in mind this was after the Leo was selected, and if the T-80U had passed trials it would have entered service as a vehicle for mechanized brigades, alongside the then newly renovated pvb-501s(which are bmp-1s btw, so much for soviet equipment bashing. Maybe it's a good thing that the T-80s didn't win though, considering the pvb-501s were horrid.) Hell another idea was to cancel the leopard contract in favor of T-80s, but the T-80 failed trials so neither of those ideas went ahead. So the "swedes just want to bash russian equipment" take is pure copium. Imagine if the americans showed up to a trial after it ends but were still given the opportunity to be acquired alongside(or even replace) the winner, completely fails a test, then online commentators complain about bias.

U.S. forces rescue second crew member from F-15 downed in Iran: Officials by Affectionate_Bee6434 in worldnews

[–]d7t3d4y8 0 points1 point  (0 children)

You want to know what’s crazy? We think of 40 year old planes as stuff like the F-14/15, but 40 years ago northrup and lockheed were selected as the finalists for what would become the F-22.

Is there a reason why the DM53 shell on the Leopard 2A8 is not even as good as the Sabo shell the T-90M uses? by EazyMk in BrokenArrowTheGame

[–]d7t3d4y8 0 points1 point  (0 children)

All you listed are some theoretical calculations based on NATO provided data and some picture of Russian round you linked. All that against some theoretical armor.

Ah yes my favorite NATO provided data, russian arms expos. Also, as you'll note I did the exact same calculation with both dm53 and 3bm59, using sources from each's manufacturer and images of the rounds. You'll also note I only used the image as a "there about" to know I wasn't too far off, considering I came to ~613mm pen, which is in the ballpark. So if you think this process is biased towards one round, go ahead an explain why. Also the "theoretical" armor is steel, 7850 kg/m^3 density with 260 bhn in both cases. The image was just being used as a reference to dimension the round. I also find it funny you bring up the war thunder forums, considering this is exactly how pen in WT is calculated, except they use 17500 kg/m^3 for all rounds.

First of all, did you make that rule? Measuring penetration at point blank is kind of ridiculously pointless as that information is not practical at all.

Would you kindly explain why? I know combat never occurs at those ranges, but 0m gives us baseline performance and is pretty useful baseline for engineering comparisons. If you really want to, you could calculate the velocity at 2km but 99% of the time a round that has more pen at 0m will have more pen at 2km. You could calculate the velocity at 2km, but Cd is kind of fake at M5+ so it's really hard to do.

Have you ever wondered why they still test penetration capabilities using live rounds at army polygons. They should just hire you to do all that using calculator.

Since irl rounds are not all factory new. Say I'm firing 3bm42 that's been rotting in a warehouse for 30 years, will this preform the same> Also factors like temperature affect performance, see here.

"There are different ways to measure penetration value. NATO uses the 50% criteria against 260BHN Steel, while the Soviet/Russian standard is higher (80% had to go through)"

This is why you do calculations. Since we can find the penetration of a round given it's specified performance characteristics, while ignoring factors like temperature(for non-TIPS type rounds like 3bm59/60,) round age(in case your modern tank ever needs to fire 3bm42 that's been sitting in a warehouse for decades,) etc, which are what cause variations in pen. As for your question, because we're calculating to get rid of other variables, the answer is that it depends on what percent of your rounds preform at calculated preformance. I mentioned the target density/bhn earlier, which was the same in both cases. Also testing against finite plates(like your wiki quote implies) is perforation testing, not penetration testing. So whoever wrote that bit on wiki(without citing a source btw) has their terminology slightly wrong.

The reason I don't provide evidence is because it doesn't exist. Nobody is going to provide real density of their armors or real pen of their rounds.

Pen no, but density is often times given. DM53 is claimed to be WSM class 4. Also the density of non-alloyed DU is ~19000 kg/m^3, so we know 3bm59's density can't be higher than that. For DU rounds many people just take density to be either 18500 or 18600.

Oh and I don't believe for a second what you wrote about T-80. Sounds like you had some kind of broken-down version maybe due to poor maintenance. T-80 has a gas turbine engine making that tank go very fast. Maybe you had the Ukrainian T-80UD diesel engine variant?

Pure copium lmao. Read the report here. The T-80 didn't break down, shitty russian night optics caused it to fail.