Collimatrix Posted October 17, 2016 Report Share Posted October 17, 2016 We live in an interesting age when cutting edge military displays look very clunky compared to consumer-grade stuff: Quote Link to comment Share on other sites More sharing options...
Sturgeon Posted October 17, 2016 Report Share Posted October 17, 2016 Yes, it's very strange. The reason as you know (but others may not) is because the debugging cycle necessary for modern military hardware is longer than the development cycle for consumer grade hardware. Quote Link to comment Share on other sites More sharing options...
LoooSeR Posted October 17, 2016 Report Share Posted October 17, 2016 We live in an interesting age when cutting edge military displays look very clunky compared to consumer-grade stuff: Well, this video is 4 years old, maybe they improved it? Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted October 17, 2016 Report Share Posted October 17, 2016 Well, this video is 4 years old, maybe they improved it? Possibly. I know they changed the helmet. Quote Link to comment Share on other sites More sharing options...
Belesarius Posted October 18, 2016 Author Report Share Posted October 18, 2016 allthe$ . jpg Quote Link to comment Share on other sites More sharing options...
Priory_of_Sion Posted October 18, 2016 Report Share Posted October 18, 2016 That picture is worth more $ than the entire military of Argentina Quote Link to comment Share on other sites More sharing options...
LoooSeR Posted October 23, 2016 Report Share Posted October 23, 2016 Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted October 24, 2016 Report Share Posted October 24, 2016 Norwegian F-35s grounded by faulty fuel tanks to be in the air by November. Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted October 28, 2016 Report Share Posted October 28, 2016 How short-legged is the F-35? Because I just noticed something surprising: Per the USAF's page on the F-22, the raptor has 18,000 lbs of internal fuel. Per LockMart's page on the JSF, all variants save the B carry more than that. So either the JSF isn't really as short-ranged as we've been led to believe, or the F-22 has insanely short legs. Quote Link to comment Share on other sites More sharing options...
Khand-e Posted October 28, 2016 Report Share Posted October 28, 2016 How short-legged is the F-35? Because I just noticed something surprising: Per the USAF's page on the F-22, the raptor has 18,000 lbs of internal fuel. Per LockMart's page on the JSF, all variants save the B carry more than that. So either the JSF isn't really as short-ranged as we've been led to believe, or the F-22 has insanely short legs. the F-22 has insanely short legs Quote Link to comment Share on other sites More sharing options...
Sturgeon Posted October 28, 2016 Report Share Posted October 28, 2016 How short-legged is the F-35? Because I just noticed something surprising: Per the USAF's page on the F-22, the raptor has 18,000 lbs of internal fuel. Per LockMart's page on the JSF, all variants save the B carry more than that. So either the JSF isn't really as short-ranged as we've been led to believe, or the F-22 has insanely short legs. This wouldn't be the first time that the military deliberately leaked incorrect information about a program as a misdirect regarding its capabilities. Hell, they did that for M855A1 of all things. Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted October 28, 2016 Report Share Posted October 28, 2016 This wouldn't be the first time that the military deliberately leaked incorrect information about a program as a misdirect regarding its capabilities. Hell, they did that for M855A1 of all things. That's one possible explanation. My immediate guess was that the F-22A was designed the same was as the F-15A was. The F-15C carries about 760 liters more fuel than does the F-15A; not because the F-15A was designed haphazardly or anything, but because a bunch of spaces were left deliberately open in case new avionics needed to be fitted. F-22A has, IIRC, provisions for future installation of sideways-looking cheek radar arrays and IRST. It may have some empty space elsewhere that was deliberately not filled with fuel tanks for future contingencies. Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted October 28, 2016 Report Share Posted October 28, 2016 NUMBERS AND MATH INCOMING Per this official USAF maintenance book on the raptor, it carries 36,515 pounds of fuel when carrying a full internal load and 4x 2503 liter external tanks. Based on the density of jet fuel that's about 17,000 pounds of fuel in the external tanks, so the raptor is carrying 19,500 pounds of fuel or so internally. That's a little bit more than quoted above, but only a little more than the F-35A and actually less than the F-35C. (Unless the Maskirovka extends to official maintenance books, in which case, hats off) Now, how does this compare to other fighters? These numbers give the raptor a substantially higher fuel fraction than many idiot reformer detractors would claim. Per Lockheed Martin's website it weighs 43,340 lbs empty, so the F-22 has a respectable fuel fraction of .31. That's about what the old time fighter mafia white papers from the '80s consider ideal. Considering that the internal space for fuel is competing with the internal space for the weapons bays, this is pretty impressive, and suggests that there aren't huge tracts of unused space in the raptor. Most contemporary fighters manage around .3, so the raptor is actually pretty middle of the road on fuel fraction. It's a bit worse than a superhornet, but a bit better than a eurofighter, a bit better than a MiG-35, and way better than a MiG-29 or Gripen (Note that this post gives a lower FF for the raptor, but not the insanely low .27 that reformists have parroted. He probably used the AF's official fuel figures, which appear to be rounded down somewhat). Again, considering that it has internal bays eating up so much of the available internal volume, this is a pretty impressive engineering accomplishment. Given the above, the raptor might have somewhat longer legs than average because it cruises faster than most fighters. According to everything I've seen, the raptor's combat radius drops significantly if it supercruises for much of the mission. However, even in subsonic cruise the raptor is probably faster than other fighters, and its most economic speed may be high transonic, while other fighters (especially with weapons on) cruise at low transonic or even high subsonic. Also, the F-35A has a fuel fraction of .39 according to the official figures, which matches or betters most flanker variants! In terms of stuffing fuel into an airframe, the F-35 is absolutely at the top of the heap for fighters. This is completely insane, because the main bays on the F-35 are about as big as those on the F-22 (F-35 lacks sidebays, however)! Belesarius and Jeeps_Guns_Tanks 2 Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted November 4, 2016 Report Share Posted November 4, 2016 Putting it another way, the F-35C carries about 23% more internal fuel than a freaking tomcat. That's not relative to its mass or anything; it actually carries that much more fuel. When the JSF gets the block 2 F135 engine, which is supposed to deliver 7-10% more thrust and 5-7% less fuel burn (their words, not mine. Not sure if that's absolute fuel consumption or TSFC), then it's going to be respectably long-ranged. Quote Link to comment Share on other sites More sharing options...
Belesarius Posted November 5, 2016 Author Report Share Posted November 5, 2016 Do you think the lack of a of hydraulics system has much to do with that freed up space? Lost was mentioning on TS that it's probably a volume vs weight deal... but, how much space and weight does having the actuators save? Not to mention the lack of having hydraulic fluid around to deal with as a hazard. Quote Link to comment Share on other sites More sharing options...
LostCosmonaut Posted November 5, 2016 Report Share Posted November 5, 2016 I'd assume that any modern fighter aircraft is probably more volume limited than weight limited (because of all the avionics and shit that gets crammed in there), but I could be wrong. Either way, the saving on the hydraulic system could definitely be part of the explanation for the high fuel fraction. Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted November 5, 2016 Report Share Posted November 5, 2016 Do you think the lack of a of hydraulics system has much to do with that freed up space? Lost was mentioning on TS that it's probably a volume vs weight deal... but, how much space and weight does having the actuators save? Not to mention the lack of having hydraulic fluid around to deal with as a hazard. It probably has something to do with it. As I understand it, the design benefits of the F-35's EHA are largely indirect. That is, the system on its own really isn't much smaller or lighter than conventional actuators. But the system can be made much thinner, so critical areas on the wing and tails and whatnot can be made more streamlined. EHA also generates less waste heat than conventional hydraulics, and since the fuel is used as a heat sink, perhaps more of it can be safely consumed (unusable fuel is accounted as dry mass). Quote Link to comment Share on other sites More sharing options...
LoooSeR Posted November 10, 2016 Report Share Posted November 10, 2016 Bronezhilet and Belesarius 2 Quote Link to comment Share on other sites More sharing options...
Ramlaen Posted November 11, 2016 Report Share Posted November 11, 2016 Quote Link to comment Share on other sites More sharing options...
Sturgeon Posted November 11, 2016 Report Share Posted November 11, 2016 In that video, Gunn confirms that F-35 has very long legs. Point for colli. Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted November 11, 2016 Report Share Posted November 11, 2016 F-35A internal fuel tanks: I wonder what the best way to make a longer-ranged version of the F-35 would be? There definitely would be a market for that sort of thing. Canada and Australia, because they have enormous airspace they need to patrol, and Israel, because they want a strike fighter that can nail targets in Iran, all come to mind. Just stretching out the fuselage seems like a more efficient option than enlarging the wings. Quote Link to comment Share on other sites More sharing options...
Sturgeon Posted November 11, 2016 Report Share Posted November 11, 2016 You could Superbug it by increasing basically everything. Quote Link to comment Share on other sites More sharing options...
Ramlaen Posted November 12, 2016 Report Share Posted November 12, 2016 Conformal tanks always seem to be the answer now. Quote Link to comment Share on other sites More sharing options...
LoooSeR Posted November 16, 2016 Report Share Posted November 16, 2016 Quote Link to comment Share on other sites More sharing options...
LoooSeR Posted November 16, 2016 Report Share Posted November 16, 2016 Sun protection glass is up Quote Link to comment Share on other sites More sharing options...
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