raptormesh Posted April 30, 2015 Posted April 30, 2015 (edited) This just reminds me of the YF-21 NASA Successfully Tests Shape-Changing Wing for Next Generation Aviation NASA researchers, working in concert with the Air Force Research Laboratory (AFRL) and FlexSys Inc., of Ann Arbor, Michigan, successfully completed initial flight tests of a new morphing wing technology that has the potential to save millions of dollars annually in fuel costs, reduce airframe weight and decrease aircraft noise during takeoffs and landings. The test team at NASA’s Armstrong Flight Research Center in Edwards, California, flew 22 research flights during the past six months with experimental Adaptive Compliant Trailing Edge (ACTE) flight control surfaces that offer significant improvements over conventional flaps used on existing aircraft. http://www.nasa.gov/press-release/nasa-successfully-tests-shape-changing-wing-for-next-generation-aviation Edited April 30, 2015 by raptormesh Quote
Shadow Posted April 30, 2015 Posted April 30, 2015 Hmm, maybe we'll see it in Northrop's 6th gen iteration of the YF-23. Quote
frothymug Posted May 7, 2015 Posted May 7, 2015 I've been working on a design project for my graduate air-breathing propulsion project and I'm trying to nail down some reasonable engine operating conditions. Maybe you guys can help me out. My mission is 11,000 km at 40k ft and at Mach 0.9. Required takeoff thrust is 100k lbf. I need to design a high-bypass unmixed flow turbofan engine to complete it. Using some real-world engines as a measuring stick, I've been able to size out an engine and used NPSS to simulate the on-design and off-design performance using a custom turbofan model that I coded up. However, I can only output performance at 100% thrust, as I haven't figured out how to vary shaft RPMs to change performance. My current design has an uninstalled SLS thrust of 103k lbf., but the cruise condition has me at about 17.6k lbf. I would assume that this engine would be one of two engines on a long range commercial jet like a 767-400ER. The current fuel flow only gives me about 9,000 km range. Since I only know of performance at 100% throttle, I need to know of a typical required thrust at cruise condition for a long range jet. If I can justify the lower thrust requirement, I can assume that the engine I've designed will meet the mission requirements. I found a forum post where someone listed the GE90-110BL's cruise thrust at 19k lbf. However, that engine's cruise velocity is probably around Mach 0.8. I know that Mach 0.9 is high for a large jet, but that's what my professor wants. I may have to resort to further increasing the fan diameter to ingest more air, but it's already at 10.8 feet and I haven't factored in the hub size yet. The GE90-115B's fan diameter is 10.7 feet. Any help is greatly appreciated! Quote
David Hingtgen Posted May 7, 2015 Author Posted May 7, 2015 Bigger fan? I think that's almost the opposite of what you want-----the GE90 etc get their raw power by having massive fans and bypass ratios------much mass, low exit velocity. Their goal is power and quiet. If you need to bump up the speed by .1 Mach (a lot for a jetliner), I'd look more into higher exit velocity----greater compression ratio. Mach .9 cruise is the realm of the 707/727----both of whose engines were basically altered military turbojets. And very skinny. (JT8D is a modified J52, and JT3C/D is a J57) Asking for 777 levels of power and range with a speed greater than anything else currently done seems like an awfully high requirement. Quote
frothymug Posted May 7, 2015 Posted May 7, 2015 The problem with higher exit velocity is that fuel consumption would have to increase. I'm using a 767-400ER's fuel tanks as a measuring stick for what should be available, which is 161,000 lbm. With my current design, I can go about 4600 miles at 100% thrust. As I was saying, I am sure that overall consumption would be reduced so that I can explain my way through completing the mission. I just want to know what required thrust at cruise would be. I already have an OPR of 64.8 (including the fan PR. 1.6/4.5/9.0, fan/LPC/HPC). I'm pretty sure that's pushing current technological limits. I would like to include at least some semblance of realism in my designs and not just cobble together whatever works. I agree that the requirements may be too high. I may just take what I have now and explain where the limitations are for fulfilling the mission requirements. Maybe if I had more time, I'd explore a geared turbofan model. Quote
frothymug Posted May 8, 2015 Posted May 8, 2015 Finally turned in my report this afternoon. I ended up sticking with the design I had originally selected. I had mistakenly used the wrong plane as a real-world counterpart. I should have been using the 777-400ER, which has tanks that are twice as large as the 767's. Fuel efficiency was more than enough to make the trip, but the cruise performance was insufficient. Max thrust was about 17,600 pounds and I needed about 19,000 pounds at cruise thrust. I was originally opposed to increasing fuel flow because it wouldn't have made the trip on the 767's tanks anyway. Part of my report was to simulate a transient solution to the case of an aborted landing where the throttle would need to be thrown from 60% RPM to 100% RPM in as little time as possible. With the sudden massive increase in fuel flow, the turbine inlet would have gotten cooked pretty good if I had set the max thrust Tt4 any higher. I had to ramp up the fuel flow over 0.9 seconds to keep the temperature from going too high... and to not stall the compressor. Quote
David Hingtgen Posted May 9, 2015 Author Posted May 9, 2015 There's no such thing as a 777-400, much less an ER version of it. Do you mean the -200ER, or the even longer-range -200LR? (the -200LR always has the GE90-11x's, -200ER's have the "standard" 3 777 engine options) Quote
frothymug Posted May 9, 2015 Posted May 9, 2015 Yep, Sorry about that. I meant the 300-ER. I was sleep deprived Quote
David Hingtgen Posted May 9, 2015 Author Posted May 9, 2015 The -200LR is the longest-range 777 of all, as a stretch will never fly as far as the original. Quote
frothymug Posted May 9, 2015 Posted May 9, 2015 (edited) Well, the mission was from DFW to Seoul, Korea. I used the 300ER because it represents a large portion of Korean Air's international fleet. Edited May 9, 2015 by frothymug Quote
David Hingtgen Posted May 9, 2015 Author Posted May 9, 2015 Just to mess with people, the 777-200LR and -300ER share wings and engines, whereas the -200ER and -200LR differ in those regards. Quote
frothymug Posted May 9, 2015 Posted May 9, 2015 As I understand it, the difference between the 200LR and 300ER is that the former has auxilliary fuel tanks in the storage compartment? Quote
F-ZeroOne Posted May 9, 2015 Posted May 9, 2015 An A400M has crashed in Spain; four people on-board have died, at least two seriously injured. http://www.bbc.co.uk/news/world-europe-32673713 Quote
David Hingtgen Posted May 10, 2015 Author Posted May 10, 2015 As I understand it, the difference between the 200LR and 300ER is that the former has auxilliary fuel tanks in the storage compartment? Well, the main difference is that the -300 is about 30 feet longer than the -200. Quote
raptormesh Posted May 10, 2015 Posted May 10, 2015 Some of you probably have seen this, but man. Love this approach. Music and wings man...straight to the heart. Quote
Valkyrie Driver Posted May 10, 2015 Posted May 10, 2015 That video on the Active Compliant Trailing Edge has curious, what do y'all know? Quote
renegadeleader1 Posted May 16, 2015 Posted May 16, 2015 I was at the Great New England Airshow today and I got a question for those who know a lot about the Blue Angels. Before they took to the air the maintaince truck was parked in front of number five for about ten minutes after the other crews cleared their planes. When the truck finally left it was trailing a lot of smoke from the back like one of the planes canisters went off. Is that normal? Quote
David Hingtgen Posted May 26, 2015 Author Posted May 26, 2015 It's the Marines! Every aircraft*! *yeah, they included drones I thought the different sizes of Hornet squadrons was interesting. Had no idea the Red Devils were that small, relatively. Quote
F-ZeroOne Posted May 27, 2015 Posted May 27, 2015 (edited) I hadn't realised that many Ospreys had been made total, let alone that much just for the Marine Corps! Lend a small navy a bit down on its budget a few? We need something to hang a radar on... Wait... "Moonlight" squadron? Are they for Love and Justice?! Edited May 27, 2015 by F-ZeroOne Quote
David Hingtgen Posted May 28, 2015 Author Posted May 28, 2015 Hoverboard. Just to put things in perspective---that's several times further than the Wright's first flight. Quote
Retracting Head Ter Ter Posted May 28, 2015 Posted May 28, 2015 Yikes, that's more Osprey's than Michael Bay's CG budget can afford to blow up! Quote
F-ZeroOne Posted May 28, 2015 Posted May 28, 2015 Real Ospreys don't look like Ospreys on film, so they use a Tiger Moth with "USMC" painted on the side instead (which would not actually be the most blatant movie example of the "But thats not a - !" in films... ). Quote
raptormesh Posted May 29, 2015 Posted May 29, 2015 Well considering one of the USMC's airwing's main role is tactical airlift I'm not really surprised. Quote
Beltane70 Posted May 30, 2015 Posted May 30, 2015 Real Ospreys don't look like Ospreys on film, so they use a Tiger Moth with "USMC" painted on the side instead (which would not actually be the most blatant movie example of the "But thats not a - !" in films... ). You mean like the MiGs they fight at the end of Top Gun? Quote
Nekko Basara Posted May 30, 2015 Posted May 30, 2015 You mean like the MiGs they fight at the end of Top Gun? Yeah, those don't look anything like real MiG-28s! (Which, by Soviet numbering conventions, wouldn't even be fighters) Quote
F-ZeroOne Posted May 30, 2015 Posted May 30, 2015 (edited) I could write a book. However, its forgivable, at least at the time. The only real MiGs in the country at the time "Top Gun" was made were flying in a top secret U.S. adversary programme. In these days of CGI, perhaps a little less so, though you can still only CGI so much. Notable offenders over the years have included: "Airwolf", where it seemed every aircraft described as a "MiG" never, ever was. "Iron Eagle" is actually interesting - although the "MiGs" were of course Israeli Kfirs, Israel did sell Neshers, an earlier type, to Argentina, so from a British tabloid news point of view that sort of counts as a "bad guy" plane. "War Games" - "Scramble the F-16s!". Cut to footage of F-15s. Most war movies made up to the time of CGI; "The Battle of Britain" features many, many late-model Spitfires that weren't in service in 1940 (the Me109s and He111s with Merlin engines are a bit more forgivable). Pretty much any movie that features a "heads-up display"; even with plenty of real footage to play with these are almost always "sexed-up". "Pearl Harbour", not so much for typical vintage warbird problems but for the tactics - pilots that tried climbing directly in front of a Zero early in the real war would very much regret it; the correct tactic (assuming that you had the altitude) was the exact opposite - to go into a dive. Any movies that feature either a F-22 or a F-35 firing its guns (or, more correctly, gun) - the most recent offender being "Avengers: Assemble!" - they never get the location or number of fitted guns right. I've even seen a documentary where the narration describes Hurricanes in action whilst showing footage of Spitfires - the poor old Hurri never gets any credit, even seventy years later! Edited June 1, 2015 by F-ZeroOne Quote
Coota0 Posted May 30, 2015 Posted May 30, 2015 (edited) It's the Marines! Every aircraft*! *yeah, they included drones I thought the different sizes of Hornet squadrons was interesting. Had no idea the Red Devils were that small, relatively. They left out the Hueys, the USMC has several UH-1Ys. Edited May 30, 2015 by Coota0 Quote
Chronocidal Posted May 30, 2015 Posted May 30, 2015 They're in there actually, mostly on the bottom rows of the Marine groups, just have to zoom in. They've got so much stuff hanging off them, they look like Cobras now. All the listings mention both the AH-1Z, and UH-1Y. Quote
Vifam7 Posted May 31, 2015 Posted May 31, 2015 (edited) "Airwolf", where it seemed every aircraft described as a "MiG" never, ever was. "Iron Eagle" is actually interesting - although the "MiGs" were of course Israeli Kfirs, Israel did sell Neshers, an earlier type, to Argentina, so from a British tabloid news point of view that sort of counts as a "bad guy" plane. However, in Iron Eagle 2, F-4 Phantoms posed as MiG-29s... which is about as bad as it gets. I believe most of the MiGs seen in Airwolf were F-84 Thunderstreak footage taken from the 1958 movie "The Hunters". Edited May 31, 2015 by Vifam7 Quote
Sildani Posted May 31, 2015 Posted May 31, 2015 (edited) Hey, they both have twin turbines... What about Iron Eagle 3, where that Burt Rutan ARES mudfighter posed as the Messerschmitt 263? Edited May 31, 2015 by Sildani Quote
F-ZeroOne Posted May 31, 2015 Posted May 31, 2015 I'd forgotten the "Iron Eagle" sequels... Speaking of Messerschmitts, some episodes of "Mazinger" feature the Me262 as a Japanese Air Self Defence Force plane! (they did actually build a similar type inspired by the German design during the war but "Mazinger" is set in Future Year 197X...!). There was also a sci-fi space combat board game whose name has slipped from my memory which tried to pass off the He162 "Volksjager" as a hyper-advanced space fighter once... Quote
miles316 Posted May 31, 2015 Posted May 31, 2015 (edited) Copenhagen Suborbitals just tested its BPM5 engine today https://www.youtube.com/watch?v=kcONo5hOSIk first test fire was 36 minutes in and the third was in the last 30 minutes of the video. Edited May 31, 2015 by miles316 Quote
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