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The Pentagon will have to live with limits on F-35’s supersonic flights (2020)
- dangerlibrary 6y agoWONTFIX. See F35-13174 "Add timeout for supersonic flight at high altitude" for details. Interesting that they called out the materials problem, and specifically the duration of research time necessary to develop and test new materials. I currently work for a company specifically targeted at shortening R&D cycles for materials companies. It's an interesting AI application - materials data tends to be small, and sparse, because each data point is expensive to generate. But you have the benefit of physical properties being bounded in the real world, where we already know certain relationships. So you need a way to inject ground truth into your model(s) so that you aren't trying to have your model re-learn the boiling point of water.
- nuisance-bear 6y agoSupersonic cruise was an explicit design requirement for the F35, and it has been achieved using materials developed in the 1990s for the F22. Your problem set sounds super cool, and it would be nice if DOD had a functioning acquisition process that would allow people with interesting tech to out-compete companies whose boards are stacked with current and former public officials. But alas, that's not the world we live in. The sad thing is, there are probably dozens of proto Kelly Johnson's out there. But they've made defense industries so intolerable that none of them work there.
- flerchin 6y agoI don't think supersonic cruise was a requirement. F35 has to use afterburners to get supersonic.
- hollerith 6y agoDrag increases significantly as the speed approaches Mach 1.0 (which is why commercial airliners stay below about Mach 0.8), but decreases significantly after that. So, just because a plane needs afterburners to attain supersonic speed doesn't mean it needs them to remain in supersonic flight. https://upload.wikimedia.org/wikipedia/commons/0/0e/Qualitive_variation_of_cd_with_mach_number.png https://upload.wikimedia.org/wikipedia/commons/0/0e/Qualitiv...
- data_acquired 6y agoIs it the case that the nature of projects in the defence industry is such that companies are prone to consolidation into a few large contractors? In the case of pharma, given the length of time and billions needed to go from drug discovery to market means that only large companies can effectively do R&D. Is it similar for defence i.e., long development times mean only a few large companies can effectively compete? Or is the creation of oligopolies that don't allow for competition a very conscious aspect of government defence policy?
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- michaelt 6y agoIt's extremely easy for the government to accidentally create monopoly suppliers. If Amazon signs a 5 year contract to get all their delivery trucks from Ford, GM isn't going to go out of business; and when they're re-negotiating the contract in 5 years time there'll still be a vibrant competitive market. But if you make tanks or jet fighters or railroad rails, you might only have one customer. And if your only customer signs a 5 year deal with someone else, you're out of business.
- bobthepanda 6y agoMost of the consolidation has happened though because of ever more expensive weapons programs. A B52 is a lot dumber than an F35 and costs way less. Similar trends took place in commercial aviation. There aren’t successful entrants into this market despite a lot of state backing, because it is now very hard and expensive to create an aircraft that matches the performance and efficiency of the latest models of Boeing and Airbus.
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- baybal2 6y agoF22 also has a limit on how long the RAM rubber can hold, and relies on constant RAM inspections, and repairs. F35, as an aircraft created more than a decade later, is supposed to have a much better RAMs.
- daniel-cussen 6y agoOh that AI application sounds fantastic for symbolic-regression brute-forcing with the algo I'm getting ready to publish. It has no minimum amount of data. It can solve relationships with a single data point if it's exact enough.
- selimthegrim 6y agoCitrine?
- dangerlibrary 6y agoYep
- selimthegrim 6y agoNice, I’d love to know what the day to day is like. They responded to my data engineering application with “We do not currently support the state you live in (Louisiana) for remote work”
- dangerlibrary 6y agoI am surprised to hear that living in Louisiana was a barrier - we have remote workers in a large number of states. Not sure if we are still hiring in Data Engineering, but it probably wouldn't hurt to reach out and reapply if this was pre/early-COVID. It's a good company to work for - excellent learning / growth culture and a lot of very smart people who don't have cookie cutter software backgrounds.
- selimthegrim 6y agoI can try and ping my contact there again- my email is my HN name at gmail. I did express my willingness to eventually relocate as well. I think I did put in a re-app for DS recently.
- decafninja 6y agoHow did things come to where they are? My understanding is that the requirements of the SVTOL B variant were the cause of the lion's share of this plane's woes? However there's also conflicting review from pilots - many who seem to love the plane (unless they are mandated to give glowing reviews to the press?).
- spicybbq 6y agoIt is notable that several countries have held competitions to choose new fighter jets and the F-35 has generally won those competitions when it was an option. Countries like Belgium, Japan, South Korea, and Poland would be examples.
- quickthrowman 6y agoIs it really notable? 4/4 of those countries have US military stationed in them, and all of them are either defended by the US directly or as part of a mutual defense treaty.
- 35fbe7d3d5b9 6y agoGovernment procurement projects, especially international ones, aren't a great way to compare things on merit. Take Belgium: Boeing and Saab didn't even bid. Boeing hinted that the program wasn't truly a "level playing field" - and then there were leaks that suggested the Belgian military promised NATO they'd purchase the F-35 years earlier and set the procurement process up to ensure the F-35 would come out on top.
- ericbarrett 6y agoI'd suspect politics, monetary incentives (not coarse bribes, but rather discounts, money for other programs, soft political support, and so on). And behind all that, "Can't get fired for buying IBM" syndrome[0]. [0] http://www.ipglossary.com/glossary/no-one-ever-got-fired-for-buying-ibm-computers/ http://www.ipglossary.com/glossary/no-one-ever-got-fired-for...
- decafninja 6y ago
- whalesalad 6y agoHN is fascinated with bashing this aircraft.
- the-dude 6y agoThe F35 is an employment program, not an aircraft.
- jp555 6y agoAlso forces adversaries to divert money into counter-F35 activates (or copying the f-35), and this is also a type of geopolitical weapon.
- toomuchtodo 6y agoThese are the worst broken windows. So much waste for so little gain.
- the-dude 6y agoStarwars worked really well.
- Red_Leaves_Flyy 6y agoWe can't be losing talent to China/EU/Russia. So the bureaucracy feeds the bureaucracy.
- woeirua 6y agoPlease do tell that to the pilots who are flying the F35.
- offtop5 6y agoHmm, I feel like the trillion or so spent on this expensive military flex would be better used to solve homelessness. The whole thing doesn't make much sense, what is this for ? Why are we still acting like we might need to fight Russia or something. Even if you are imagining WW3 I reckon human pilots will be obsolete by then. A drone would be able to fly faster and react quicker
- zozin 6y agoWhile a limitation, I don't really think this affects the platform much. It's not an air superiority fighter like the F-22, it's much more of an air "quarterback" to to speak. It flies up, sees the defense, sees the offense, tells the offense where to go and what to do, and in case of emergencies can defend itself if need be. Supersonic flight also requires a lot more fuel and the internal fuel tanks on the F-35 also severely limit the amount of time the plane can sustain supersonic speeds. Obviously you want to have your cake and eat it too, you want a stealthy, extremely high speed, capable, and affordable platform, but that's not how the real world works. I imagine the operators would rather have F-35s in the air for longer periods of time to act as a force multiplier rather than have the jet be able to zoom around 10% faster for 30-40 seconds at a time.
- bradleyjg 6y ago> it's much more of an air "quarterback" to to speak I thought that was AWACS? Why is an F designated plane not in a fighter role?
- piva00 6y agoIf we are going to stretch the analogy, AWACS could be the watcher on the stands, telling the coach the big picture plays. The quarterback is in the heat, calling tactics in the spur of moment. Not sure if the analogy breaks down completely from here on.
- zozin 6y agoAWACS do do that, however, in a conflict with a peer enemy AWACS would get shot down immediately since they're non-stealth sitting ducks.
- jasonwatkinspdx 6y agoThe F-35 is definitely a multi role fighter. It just also has sophisticated enough electronics it can act as a sort of "mini AWACS" when useful. And it's a lot more likely to survive in a peer fight, while AWACS will be pushed back beyond standoff range.
- rswail 6y agoSo perhaps this aircraft should be considered a "mini AWACS" alongside drone fleets such as is being developed by Boeing and RAAF instead of a "fighter" itself. https://www.abc.net.au/news/2021-03-02/loyal-wingman-first-flight-australia-boeing/13207388 https://www.abc.net.au/news/2021-03-02/loyal-wingman-first-f...
- dingaling 6y agoBut that magic is all the result of avionics, which aren't inherently unique to the F-35. They could also be applied to the new-build F-15, including conformal antennas, which offers much better kinematic performance.
- MilStdJunkie 6y agoThere's so much FUD dusted up literally every conversation about this program that it's unlikely any minds will be changed before the next peer conflict. Expensive education, certainly. If you love the thing, stop reading, and we'll come back and have this discussion after the SCS conflict. That said, those of us on Team Bash aren't doing this out of malice or . . whatever motivation I would have for "trash talking" a military program that indirectly pays my checks. Hell, I should be strapping on my little flouncy skirt right now and getting out the pom poms. It's a fine development platform, and we're learning lots of stuff from the 35. It'll make a great bomb truck over whatever 'stan we need to blow up at the time. Anyways, the thing can't fight. (TL;DR: the plane is in a catch-22 of not having enough range when it carries enough weapons and not having enough weapons when it has enough range. Along with a bunch of other stuff, but that's the big one, and supercruise is a direct part of that) * 1000 NM radius is not enough for SE Asia, at all, certainly not for a Hainan mission. Flying dirty (unstealthed), it flies low for terrain masking, and now it's lucky to get 500 NM. * persnickety: pre-chilled fuel; exotic conditioned electricals; 30,000 dollar CPFH + regionally specific MDF for the active LO systems * Can't stealth mount BRU-61, AARGM-ER/AGM-88G, AIM-260 JATM, JAGM-F, SPEAR 3, JSM, APKWS, AGM-183 ARRW, AGM-158C/D LRASM/JASSM-XR, SACM/CUDA/PEREGRINE, Hammer/Hatchet. Remember, if it has to fly dirty, it has to fly low, and now you're dealing with a 500nm range. The weapons fitment issue is probably the biggest source of FUD on this program, with lots of "it carries X Weapon" when really all they checked is that X fits inside of a NxNxN space. * Can't supersonic launch missiles no supercruise. Subtract 30% from your missile range - a lot of rocket power to make a shock cone on the missile nose. * 8 seconds (A), 16 seconds (B) and 43 seconds (C) over KPP requirement for missile sprint, during the run up to IOT&E and OPEVAL. * 4 AMRAAMS internal, and let's be honest here, you need 3 to guarantee a kill in ECM environment. Take more than 4 and now you're flying "dirty", so you fly low, halving the combat radius if you're lucky. And don't forget, it doesn't have the speed to run once it empties its magazine, and from behind IRST will see its burner from 100k or more. * APG-81, MADL, stealth coatings were pirated in the late aughts, compromised
- hef19898 6y agoI would add potential issues operating it from advanced airbases in a major conflict. This planes needs so much high tech ground gear to be at 100% capability, that I think it will have serious problems if air filed ops are actively threatened. And in theaters where air bases aren#t threatened by a near-peer enemy you don't need haf of the F-35s capabilities. Using it to defend Europe against a Russian invasion is different, so.
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