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dietcokefiend posted:So who is the go-to place for piston aircraft engine these days? There are three major manufacturers for piston aircraft engines currently in business, with two of those companies controlling the vast majority of the market. Lycoming (owned by the same parent company as Cessna) and Teledyne-Continental are the two biggest piston engine makers, with both selling lines of horizontally opposed, air cooled engines ranging from ~100HP 4-cylinder models, up to 6 and 8(for Lycoming) cylinder versions in the 300-400hp range. The engines are incredibly expensive, with the smaller engines going for around $35,000 new, and the biggest 8 cylinder Lycoming selling for about $120,000. A rebuilt engine runs in the $25,000-80,000 range, and overhauling an engine (which happens about every 2,000 hours), runs from $12,000 for small engines up to around $70,000 for the bigger models. Both Lycoming and Continental produce engines that are almost exclusively direct drive (they redline at around 3000RPM) and run on leaded fuel, but some of their larger engines run through a reduction gear setup on some aircraft models. The third player in the piston market is Rotax, which produces engines for smaller light sport or homebuilt aircraft. Rotax started out making engines for snowmobiles and jet-skis, but branched out into aircraft engines some time ago. Unlike Lycoming and Continental, Rotax engines are all reduction geared (with the engines running around 5,500rpm with a 2.43:1 reduction gearbox to let the propeller rotate at a normal speed. Rotax engines are also liquid cooled and generally run on premium auto gas, since they don't play well with the lead content found in Avgas. There is a company called Austro that recently introduced a diesel engine for aircraft use. The AE-300 is a liquid cooled diesel engine (although it runs on Jet-A in aircraft) that puts out around 170HP, but does so using about 50% less fuel than a conventional piston engine would. Homebuilt aircraft run on pretty much anything you can think of, with Volkswagen and Subaru engines being quite popular for their reliability and horizontally opposed design. ApathyGifted posted:Wait. He modified a Nissan VG30. As in the 3.0L, <300 hp VG30? To get 1,000 horsepower? As far as I can tell. The engines were based on the VG30, but were heavily modified and built by a company called Electramotive. I can't find any information as to exactly what was modified on the engines, likely because they were purpose built for Pond Racer and were way too unreliable for any other application. azflyboy fucked around with this message at 08:02 on May 12, 2010 |
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May 12, 2010 07:57
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Skyssx posted:Rotax engines work just fine on AVGAS. The Predator/I-GNAT/Warrior/Mariner/Name-Of-The-Week all burn it. It's easier to procure in theater, less likely to absorb moisture, and increases reliability while reducing head temps. Rotax engines can run on Avgas, but the lead causes deposits to form in the engine, which isn't great for them. I pulled this from the website of a Rotax service center regarding use of 100LL in their 4-stroke engines. Rotax service center posted:It is possible but not recommended to use 100LL AVGAS, since the the lead content is like cholesterol to your engine: it will accelerate wear on the valve seats, create deposits in the combustion chamber and sediments in the lubrication system and gearbox. Increased maintenance is necessary to compensate. Unlike "conventional" aircraft engines, lead is absolutely not essential to the proper lubrication and operation of a Rotax 4-stroke aircraft engine. The increased octane rating also has no marked advantage for the operation of your engine.
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May 12, 2010 19:24
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grover posted:It's even worse at take-off when the wing tanks are heavy with fuel. After watching that 777 wing-flex-to-failure test, I'm a lot less worried about a small bit of movement during flight. During early testing of the U-2, pilots encountered situations where the wings were flexing out of phase with each other, which had to be incredibly unnerving in an aircraft that delicate. When the U-2 is operating at lower altitudes, it actually requires a special "gust alleviation system" to keep turbulence from overstressing the fuselage and wings. When activated (normally when climbing to and descending from cruise altitudes), the deflects both ailerons 7.5 degrees above their neutral position, and it also drives the flaps upwards 6.5 degrees. By deflecting the flaps and ailerons, the system unloads the wing, which drastically reduces the forces that turbulent air can impart to the aircraft.
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May 22, 2010 07:03
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Revolvyerom posted:Somebody learn me some airplane From what I understand, the nose splitter is primarily there to duct air around the cockpit to the engine. The way the Mig-15 is designed, the cockpit sits directly between the intake and the engine, so the splitter takes the incoming air and divides it into ducts that pass on either side of the cockpit and into the engine. During the Mig-15's operational life, the splitter also proved a handy place to mount things like landing lights and radar antenna, although those components got moved around quite a bit as production progressed.
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May 27, 2010 19:58
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Minto Took posted:This is what I've wondered. I know a B-52 served as an engine test bed for the 747-100's engines, but I've heard is nearly impossible to re-work the B-52 fleet to move from 8 to 4 engines. Are the plumbing/electrical/mechanical connections so complex that the Air Force can't swap out the current layout for four engines with better economy and higher thrust? Re-engining the B-52 fleet is actually being considered, but it seems to be dead at the moment. Boeing proposed converting the B-52 fleet to use Rolls-Royce RB211's (which power the 747, 757 and 767), but the GAO claimed that the Boeing cost study was inaccurate and the program would be too costly, which stopped the idea in the early 2000's. In 2003, a Defense Sciences Board claimed that the GAO report was flawed, and the original Boeing proposal was correct, resulting in the Defense Sciences Board urging the Pentagon to re-engine the B-52 fleet. That recommendation was made in 2004, so it does appear that the re-engining program is dead for now, but since the B-52 is supposed to be around for another 40 years or so, I wouldn't be surprised if the engines aren't replaced eventually.
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Jun 2, 2010 15:09
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VikingSkull posted:The Hustler is the best plane, listen to that bastard go! The Hustler is even more awesome because of how they tested the ejection seats. Due to the high speeds the B-58 could reach, there was concern that conventional ejection seats wouldn't be survivable if used at Mach 2, so an "ejection capsule" which surrounded the seats was devised to protect the crew. For reasons I've never seen explained, the ejection capsules were tested by strapping a live (and presumably tranquilized) bear into the seat, and then firing it off to see if the occupant survived. I just love the mental image of someone then having to open the capsule, praying that they weren't going to be greeted by a pissed off bear when they did so.
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Jun 4, 2010 21:20
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slidebite posted:Here is a picture of said bear and ejection capsule. From what I've read, the capsules were configured with bars that automatically pulled the occupants' legs into a fetal position as part of the ejection sequence. The F-104 used a similar system that required the pilots to wear spurs on the back of their boots. The spurs attached to sockets in the ejection seat, which were in turn attached to cables. When the pilot ejected, the cables were automatically retracted into the seat, pulling the pilots' feet back in order to make sure that a flailing leg wasn't amputated by slamming into something upon ejection.
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Jun 4, 2010 21:33
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InitialDave posted:Yeah, a Russian one, this could have resulted in a pretty good Hartlepool Monkey situation should some rednecks have found it. Something like that happened when the CIA decided to train Taiwanese pilots to fly U-2 missions over China in the 1950's through 70's. The entire training program was kept classified (the aircraft itself was still secret when it started), which lead to an interesting incident in Cortez, Colorado. On August 3, 1959, a Taiwanese pilot on a training mission experienced a total engine failure over Colorado at night, but the pilot was able to dead-stick the airplane into the Cortez airport (due to its' runway lights being on), despite it not appearing on his charts. After the airplane landed, the airport manager came out to see what the hell had just showed up on his ramp, only to be met by a figure wearing a space suit gesturing and yelling "Quick! get gun, guard airplane! Very Secret!" in heavily accented English. For his actions in saving the still-secret aircraft, the USAF awarded the pilot the Distinguished Flying Cross, but I'd have loved to have seen the look on the face of the airport manager when the incident happened.
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Jun 5, 2010 00:17
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KYOON GRIFFEY JR posted:Man the Peacemaker is loving ugly, no wonder the B-47 kicked its rear end. Thanks to the huge wing area of the B-36, it was actually more maneuverable at high altitudes (lightened aircraft commonly cruised at 50,000ft) than most of the fighters of the 1950's, which annoyed the Air Force and Navy to no end, since their fighters either couldn't reach those altitudes at all, or if they could, they were essentially ballistic projectiles and found themselves outmaneuvered by a 400,000lb bomber. There was also a great story in Air & Space a few years back about B-36 crews messing with fighter pilots. As part of exercises, interceptors were often scrambled to intercept "enemy" B-36's, and the fighter pilots greatly enjoyed harassing the slow moving bombers. During one such exercise, an F-89 pilot tried to form up with a B-36 to show off, only to find himself whizzing past the larger aircraft. Undeterred, the fighter pilot set himself up for another attempt, with the same results as before. Somewhat annoyed by this point, the F-89 pilot extended flaps and speed brakes in an attempt to pace the B-36, which ended with the fighter stalling and losing several thousand feet in the recovery, at which point the pilot gave up and went home. Some time later, the F-89 pilot was told by a former Peacemaker crewman that the B-36 was capable of controlled flight at around 100MPH when lightly loaded at lower altitudes, which was far slower than the jet powered F-89 was capable of flying.
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Jun 10, 2010 23:40
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2ndclasscitizen posted:It's certainly a thing of beauty, but my first thought was: The long nose on the H-1 was a result of Hughes needing room for a lot of fuel to set a transcontinental speed record. Even with a set of longer-span wings installed for the transcontinental record (a shorter set were fitted for the absolute speed record), there were only 75 gallons of fuel per wing, so the H-1 carried 150 gallons of fuel in two tanks between the cockpit and engine. Howard Hughes also "borrowed" the engine on the H-1 from the US government. When the aircraft was being designed, Hugues realized that there wasn't an engine then in production that could produce the kind of power he needed, but he had heard about Pratt and Whitney developing an engine for the US Army that might meet his requirements. Somehow, Hughes managed to convince the US government to let Pratt and Whitney lease him an R-1535 for the H-1 (claiming it was for development of an advanced fighter), at which point he had the engine disassembled in the quest for more horsepower. Stock, the R-1535 could produce 700hp, but Hughes needed more power than that, so he had the engine modified and spent a fortune fueling the aircraft with (then experimental) 100 octane fuel, which boosted the output to around 1000hp without blowing up the engine. The tweaks clearly worked, since the H-1 set a landplane speed record of 352mph, followed by a coast-to-coast speed record of 7hrs 28 minutes, averaging 322mph. As for the "leased" engine? Hughes never paid Pratt and Whitney for the engine, nor did he bother returning it to the US government, and to this day it's still fitted to the H-1, which has been on display in the Smithsonian since 1975.
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Jun 22, 2010 03:47
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jandrese posted:As to why they don't just use older style reciprocating engines, the answer is that Turboprops have fewer parts and less required maintenance, so they're cheaper to operate over the long run (even if they do cost more up front). Turbine engines also have a huge power/weight advantage over reciprocating engines, in addition to being far more reliable. The Pratt and Whitney R-4360 produced 4,300hp by the end of development, but weighed almost 3,900lbs, which meant it's power/weight ratio was only slightly higher than 1/1. Most turboprops have power/weight ratios in excess of 2/1, and do so without the vibration or reliability issues of piston engines. As an example, the 28 cylinder R-4360 used two spark plugs per cylinder (56 per engine), and each engine used both a turbocharger and supercharger along with reduction gearing for the propeller, which made them less than simple to maintain. Even when running properly, a large radial still required a ton of maintenance, with engines in commercial service requiring a total overhaul about every 600 hours. By contrast, a modern turbine engine might get inspected every few hundred hours, but will last thousands of flight hours in normal service before needing a replacement or major overhaul.
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Jun 23, 2010 06:08
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Sterndotstern posted:
Sikorsky used radial engines into the early 1950's due to the simple fact that turboshaft engines capable of powering a helicopter hadn't been developed yet. Turboshafts were first developed in the late 1940's, but it wasn't until the mid 1950's that they were refined to the point of making the large radial engines obsolete.
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Jun 30, 2010 02:32
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Sterndotstern posted:These are both fantastic shots and utterly staggering displays of human ability. Nothing impresses the mind like perfect control. What makes it even more impressive is that those guys fly without the benefit of a G-suit. Due to the precision required for that kind of flying, Blue Angel pilots fly bracing their right arms on their right thighs, and since G-suits use inflatable bladders on the abdomen and legs, the suit would jostle the stick whenever it inflated. To compensate for the fact that most of the formation maneuvers pull about 4G's (the solo pilots pull close to 7), the pilots have to tense up their abdominal and leg muscles during maneuvers to keep from blacking out. After the team experienced a fatal crash while practicing for a show in 1999 (caused by a pilot blacking out in a high G turn), the Navy considered forcing the team to wear G-suits, but relented after it was determined that the accident pilot was suffering from a rib injury that kept him from tensing up properly during flight.
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Jul 2, 2010 06:56
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Nebakenezzer posted:That's some beautiful camo. Is it real? If so, what's it for? It's real. The two F-16's with the "AK" tail codes are based out of Eielson AFB in Alaska, and the paint schemes (often referred to as "Flanker" camo) are put on aircraft that are used as aggressors in exercises like Red Flag.
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Jul 4, 2010 02:31
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MrChips posted:And for an aircraft as large and complicated as a B-29, the outlay of dollars and man-hours to keep one airworthy is so great that you essentially need to start with an aircraft that requires only minor work to get airworthy, as the Commemorative Air Force did with their flying B-29. Fifi had actually been used as gunnery target that sat in the California desert for 17 years (along with several other B-29's) before the CAF came along. When the CAF finally got permission to take the aircraft, it took a team of volunteers 9 weeks of almost nonstop work to install new parts (many from the other B-29's at the range) to get the aircraft airworthy and flown to Texas, where another 3 years of restoration were still required. As for Kee Bird, Greenamyer was an idiot. There was no reason to fly the aircraft off the ice, and the recent restoration of Glacier Girl (a P-38 buried in a glacier for 50 years) to flight status showed exactly the right way to go about getting a priceless aircraft recovered, restored, and flying, all without setting it on fire.
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Jul 22, 2010 03:15
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Sterndotstern posted:Awesome! I've always wondered about the details of aircraft props, now I can finally find out! If anyone's interested, the USAF animation of that accident is on youtube. http://www.youtube.com/watch?v=fI5xTmmPbsY The accident aircraft had just departed Dover AFB when the crew got an indication that the number 2 thrust reverser had unlocked, which required them to shut down the engine and turn back to Dover for landing. As the aircraft approached Dover, the pilot accidentally swapped the throttles, and began manipulating the #2 throttle as though it had power, while leaving the #3 engine (which was still running) at flight idle. Although the C-5 was capable of flying on 2 engines, the crew then used a flap setting that produced more drag than the engines could overcome, which resulted in the aircraft crashing into utility poles short of the runway. All 17 people on the aircraft survived, but the airframe was scrapped, with the cockpit slated to be used as an avionics test bed for future C-5 upgrades.
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Jul 22, 2010 07:43
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dietcokefiend posted:What is the average military pilot worth? I figure from a basic training/skill standpoint there has to be some sort of value places on their lives. This also plays into the next question. The current Army ROTC helicopter contract requires 8 years of service after finishing, so that should give you some idea of how expensive flight training is. That said, the Chinese students that train in the US have it far worse. Their training is paid for by an airline, but in return, the student essentially becomes an indentured servant for that company. When they sign the contract, those students are required to work for the airline for 20-30 years after finishing training (I've also heard of 99 year contracts as well), and they're automatically required to pay around $300,000 if they try and leave early. azflyboy fucked around with this message at 06:43 on Jul 24, 2010 |
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Jul 24, 2010 06:36
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slidebite posted:I think you picked a couple of really strong candidates. I would also probably throw the UH1 series in there too. They've been used for everything. The KC-135 certainly goes on the list, since it's been in service since 1957, and some of the aircraft may be flying until around 2040, which is also about when the B-52 might finally retire. I'd add the U-2 to the list as well, since it's about the same age as the B-52 or C-130, and managed to outlast both the USSR and it's own replacement.
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Jul 24, 2010 23:06
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meltie posted:How does one 'archive' an aircraft when it goes to a museum or storage? For things like AMARC (the huge "boneyard" facility in Tucson, AZ) where the idea is long term storage with a possible return to flight, the process is something like this; After taking out batteries and things that might explode, the fuel and hydraulic systems are completely drained and flushed, and I think some kind of preservative gets run through the lines to keep them from rotting. After that, if the aircraft will be stored outside, it gets shrink wrapped in heavy white plastic that not only covers the windows (to protect them and keep the interior from getting sun damaged), but is used to cover intakes, exhausts, and anywhere else that dirt, water, or wildlife might get in. Airliners can be stored in a similar method for long term storage, but for shorter term storage, they're "unwrapped" and the engines are run up periodically to keep things working. Military aircraft in museums are gutted of electronics, pyrotechnics, and anything that might be classified before the government lets the museum take possession, and what happens after that is pretty variable. Aircraft that sit outside at museums need repainting every so often, and in cases of rare or important aircraft (like the Memphis Belle) the government has "repossessed" aircraft that aren't being properly cared for. Indoor museums pretty much just keep their aircraft away from direct sunlight, humidity, and abusive guests, and they'll rarely need anything more than a dusting or washing. Many of the older aircraft in the Smithsonian are actually still wearing their original fabric coverings and paint, although their Jenny (which has an 80 year old covering) recently had to be taken off display after tourists damaged it by throwing coins at it from a balcony. azflyboy fucked around with this message at 02:14 on Jul 25, 2010 |
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Jul 25, 2010 02:02
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Tindjin posted:I should hope so. The A380's design was done 40 years after the 747. Lots of changes from the early 60's to the turn of the century. The 747's nose design actually comes from it originally being an entry into the competition for what would eventually become the C-5, combined with the thought the aircraft wouldn't be in passenger service very long. When the USAF requested proposals for a new heavy lifter, one of the requirements was that the cargo bay had to be at least 17ft wide, 13.5ft high and 100ft long, with doors in both the nose and tail, which meant the cockpit had to sit on top of the cargo bay. During the design phase of the 747 in the mid 60's, the prevailing notion was that it would soon be replaced on passenger routes by supersonic transports, so Boeing designed the aircraft to be easily converted into a freighter when that happened, which meant the cockpit was placed on top of the cabin to allow a nose door. Thanks to the cockpit placement, all purpose built 747 freighters have a nose that hinges upward like a visor, which makes loading the aircraft (especially for bulky items) much easier than smaller doors on the sides of the fuselage. Since the A380 was mostly intended to work as a passenger carrier, Airbus decided to just keep the cockpit on the lower deck to make things a bit easier for pilots. Although they did originally offer an A380 cargo model, Airbus managed to delay A380 deliveries long enough that all of the cargo customers canceled their orders, with Fedex buying several new 777 freighters instead.
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Jul 26, 2010 07:36
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Ola posted:Are there any official stats on how many crashes/deaths there are every year at Oshkosh? Looking in the NTSB database, there are 12 accidents listed at OSH during Airventure from 2005 until now (the one yesterday isn't listed yet), with a total of six fatalities. However, if two aircraft collide, each aircraft involved counts as an accident, so four of the listed accidents actually took place in two events. One of the events was the collision between the two P-51's in 2007 (one fatality), and the other was when a Grumman Avenger taxied into an RV-6 in 2006, killing the RV-6 pilot.
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Jul 28, 2010 18:37
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two_beer_bishes posted:I've been a pilot for a long time and I don't recall ever hearing that term... Servo tabs are the surfaces used to reduce control forces on large aircraft without hydraulically boosted controls. They always move in the opposite direction of their control surface, which levers the control surface into moving the desired direction. Anti-servo tabs do exactly the opposite, increasing control forces by moving the same direction (but to a larger degree) than the control surface. Anti-servo tabs are most commonly seen on aircraft with stabilators (an all moving horizontal tail), since the large moving surface would lead to a very pitch-sensitive aircraft unless the anti-servo tab was in place to raise the control forces. Aileron spades aren't really servo or anti-servo tabs (they're an aerodynamic balance), since they're rigidly attached to the ailerons and work by effectively countering the mass of the control surface aft of the hinge line, which lowers the stick forces in roll. You'll occasionally see older aircraft with weights sticking forward of the rudder hinge line, which does the exact same thing as spades on ailerons.
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Aug 4, 2010 06:49
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Cakefool posted:What are the white lines on the B2? Like Godholio said, they're probably areas that someone can stand when working on the airplane, although the two on the top of the cockpit might be there to mark where the ejection seats come out when they're fired. Most airplanes are essentially hollow over large parts of the wing and fuselage, which means stepping somewhere that doesn't happen to have a structural support running underneath it is a very good way to dent a metal aircraft or put a hole in something made of composites.
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Aug 14, 2010 23:40
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Skyssx posted:Trim tabs? I don't know what you're looking at. He's talking about the triangular aileron spades, which can be seen blocking out the second "R" written on the left wing, and between the "E" and "T" on the right wing.
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Aug 16, 2010 18:43
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Godholio posted:Unlike crashing. The big advantage to ballistic parachute system is that the aircraft comes down almost vertically, and at a controlled rate. When an aircraft lands under a parachute, the landing gear and seat absorb much of the impact energy, and the human body is does a much better job absorbing an impact up through the spine than having the body whipped forward against a seatbelt.
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Aug 19, 2010 17:52
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Lilbeefer posted:And why bother asking about some silly Sidewinders in the wingtips when the real question is what possible defense could be provided by 82 F18s and a handful of cruisers in a country nearly 3 million square miles in size? Since the Russians are still flying Tu-95's around the arctic, having F-18's around to follow them as a show of force actually makes some sense. On a related topic, the US seems to be convinced the Canadians want to invade North Dakota, since there's now a Citation, two helicopters, some Cessna 182's, and a Predator based in Grand Forks for the sole purpose of patrolling the Canadian border with North Dakota. I feel so much safer knowing that we're protected from the menaces of socialized medicine and Tim Hortons.
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Sep 11, 2010 21:16
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ApathyGifted posted:Wrong hemisphere buddy. It's happened in Canada as well. During the Cold War, the USSR commonly sent Tu-95's to snoop around just outside the edges of Canadian and Alaskan airspace, and Putin restarted the flights a few years ago, as part of his "sabre rattling in the arctic" series. As recently as August of this year, the RCAF has intercepted TU-95's that were patrolling just outside Canadian airspace, so at least the CF-18 pilots have the chance to get some nice air-to-air pictures in the process.
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Sep 12, 2010 01:22
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Godholio posted:His point was that the Aussies don't have to worry about Bears entering their airspace. Those were RAAF F/A-18s in the pictures carrying live missiles, not CF-18s. Derp! Somehow I thought the pictures were from Canada.
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Sep 12, 2010 02:10
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cloudstrife2993 posted:How's this for aeronautical insanity? That honestly looks like a bunch of engineers got drunk and decided to start some welding spare helicopters and a scaffolding together to see what would happen. On the topic of crashes and helicopters Why you shouldn't try and fly a helicopter without an instructor or license. http://www.youtube.com/watch?v=uI4d5AeAi7g Apparently Charlie didn't see the hanger there. http://www.youtube.com/watch?v=RkeqQY3t174 A turboprop P-51 taxis into a helicopter. http://www.youtube.com/watch?v=pFbD5NUcJnM&feature=related
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Sep 16, 2010 20:17
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More aeronautical insanity! During the 1950's, both sides of the Cold War began worrying about the possibility of a sneak attack disabling their airfields, so experiments began on "zero length launch" systems for fighters. Initially, the idea was to shoot fighters off a track (actually a modified cruise missile launcher) using a booster rocket to get them up to flying speed, and then have them land gear-up on an 80X800ft inflatable mat at the end of the flight. http://www.youtube.com/watch?v=cE6QmjAlHT8 The USAF conducted tests using an F-84 fired from a modified cruise missile launcher (and using the rocket from the missile as well), and although the takeoffs went surprisingly well, the inflatable mat idea didn't really work. The first mat landing resulted in the arresting hook of the aircraft tearing up the mat, damaged the aircraft beyond repair, and gave the text pilot severe back injuries. Although later landings went a bit better (the aircraft could at least be used again), the idea was judged to be unworkable and scrapped. Since the launch part of the system worked pretty well, the USAF expanded to shooting F-100's from trailers, strapping the aircraft to a rocket that produced 130,000lbs of thrust and took it from 0-275MPH in about four seconds. http://www.youtube.com/watch?v=wDstVGAmI74 http://www.youtube.com/watch?v=oImq1glnOds&feature=related Somewhat surprisingly, the launch system worked almost flawlessly, and aside from an incident where the booster failed to detach from the aircraft (requiring the pilot to eject), there were no major accidents. Although shooting fighters off of trailers was clearly possible, the logistical and security concerns (like fitting through tunnels or under bridges) posed by the setup, combined with the increasing effectiveness of cruise missiles and work on other short takeoff systems meant the idea was never put into service in either the US or USSR, which had conducted similar experiments.
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Sep 19, 2010 18:37
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Trench_Rat posted:is there anything more NAZI SUPER SIENCE than the ME 323 There are a few other crazy Nazi designs out there... The He-111Z was created as a tow aircraft for the ME-323, and was built by just taking two He-111 bombers, attaching them at the wing, and adding a fifth engine at the middle of the new wing.   Click here for the full 1024x904 image. A total of 12 were built in 1942, and by the end of the war (after an unremarkable career), eight had been shot down or bombed on the ground, and the remaining four examples are presumed to have been destroyed. In 1939, the Luftwaffe began work on the Me-163, which remains the only rocket powered fighter to ever enter service.  Click here for the full 800x414 image.  Entering combat service in 1944, the Me-163 would take off from a jettisonable wheeled dolly, climb at a 45 degree angle to around 35,000ft, and then make one or two high speed (around 500MPH) passes on Allied bombers before having to glide back to base after running out of ammo and fuel. The Komet was powered by a rocket engine that ran on a mixture of methanol and hydrazine hydrate (which burn when mixed), which gave the Me-163 an alarming tendency to explode after a hard landing or even when sitting on the ground, since the metal fuel lines tended to develop leaks. Although the Me-163 was far faster than any Allied fighter and was almost impossible for defensive gunners to hit, it's short flight time and the difficulty in hitting a target at high speeds meant that the Komet only managed to shoot down about 16 Allied bombers during 1944-1945.
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Oct 7, 2010 22:17
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CommieGIR posted:They didn't help the war effort because they were TOO LATE. If they had been present any earlier in the war...it could have been a turning point. With most of the German superweapons, putting them into service a couple of years earlier would have done nothing more than possibly prolong the war by a year or two, since the major mistakes Hitler made (failing to close the Atlantic, shifting the bombing of England away from factories and airfields, and invading the USSR) were strategic decisions that technology couldn't have overcome. The invasion of the USSR was pretty much doomed from the start by Russian winters and Stalin having no qualms about massive casualties in battles. Aside from those factors, Hitler's refusal to allow Nazi troops to retreat from hopeless situations combined with his constant replacement of experienced officers with "yes men" made a bad situation progressively worse, which is something giant guns and rocket powered fighters couldn't change.
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Oct 8, 2010 04:29
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Nerobro posted:as engine failures go, that's not so bad. Looks a like "just" a simple engine fire. Still, it's not something Airbus wanted to have happen, especially when a carrier publicly grounds their flagship product in response to an uncontained engine failure. Over the last few years, Airbus has had the A380 delivery delays (including being forced to cancel the freighter version), the loss of the Air France A340 and subsequent revelations of icing issues in A340 pitot masts, the constant schedule and budget overruns with the A400M, and changing the A350 design every five minutes in attempt to copy the 787. As screwed up as Boeing's 787 schedule has been so far, they still have yet to reach the "piss off a customer and have to cancel an entire production variant" Airbus hit a few years ago with the A380.
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Nov 4, 2010 20:48
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Minto Took posted:Pretty sure Qantas uses Rolls-Royce engines on their 747s too. Somebody's going to be in trouble! Quantas also had an incident earlier in the year where one of their 747's experienced an uncontained engine failure shortly after leaving San Francisco, so it's either an issue with the engines or their maintenance, which means a large company gets in trouble either way.
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Nov 5, 2010 19:44
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InitialDave posted:They are, somewhat unsurprisingly, saying they believe the A380 incident is unrelated to their maintenance. The Trent family has never been fitted to a 747, so the aircraft in that incident would have been using an RB211. However, I'm pretty sure some RB211 models use a hot section from the Trent line (I don't know about the engines Qantas uses), so there could be a problem that spans two RR engine lines now.
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Nov 5, 2010 20:32
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grover posted:There are always engineering changes/updates in projects this big. True, but fatigue cracks appearing in a major structural component at less than 10% of the design life seems like a pretty "oops" this late in the program, especially with all the other schedule and budget overruns LockMart has run into during the F-35 project.
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Nov 22, 2010 03:04
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Ola posted:But this is the complete opposite. This is the most incredible NTSB report on a GA accident I have ever read. Put something soft on your desk, your jaw will be doing multiple drops. Obviously, real men don't bother with things like "reading manuals" or "connecting the flight instruments". I'm amazed it took him that long to get himself killed, especially since he had a lovely combination of useless instruments (that he didn't understand anyway) and a propeller control system that required constant babysitting for any change in power settings.
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Nov 27, 2010 21:58
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Ola posted:Hahaha I love stories about aircraft idiosyncrasies. I don't have any links or usable memory available, but have read some rather hairy stories about, for instance, Royal Navy pilots in the early jet age. Carrier ops in the 50s was pretty rudimentary stuff. I've got copies of pilots handbooks for a bunch of early jet aircraft, and some of their "quirks" are pretty terrifying. On the YB-49 (a six-engine, jet powered flying wing built in the late 1940's), the throttle system requires something like three pages to describe, and makes it quite clear the engines would pretty much quit or catch fire if someone looked at them funny. When increasing or reducing thrust under 10,000ft, the throttles had to be moved incredibly slowly (~30 seconds from idle to full power), since the engines would flame out or catch fire if the throttles were moved faster than that. The B-47 suffered from the same slow throttle response (which makes an aborted landing interesting), so the aircraft were occasionally fitted with a parachute that was deployed on approach to allow the engines to be kept at a higher RPM without accelerating the airplane. The B-47 manual also describes the aircraft as having an oxygen system installed, as well as reminding the pilot that "ash trays for the crew are conveniently located", which seems like there was a bit of a potential for disaster.
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Nov 29, 2010 18:23
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slidebite posted:The one at 1:35 has outriggers on the wings. Do the others have them and they're not used or is that plane an oddball? The outriggers fall away on takeoff, so that incident might have taken place during takeoff.
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Dec 7, 2010 22:25
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Ola posted:That made me wonder too. There is quite a lot of glass fiber aircraft around, is it very different from carbon fiber? Fiberglass has been used on smaller aircraft (often on non-structural bits like cowlings or fairings) for years, and it's actually pretty durable. I used to fly a late 70's Cessna 172 that had an aftermarket fiberglass cowling installed, and it survived having the alternator pulley break off in flight (and subsequently ricochet inside the cowling a few times) with nothing more than a couple of dings to the paint. Fiberglass also tolerates cold better than a lot of plastics. On newer 172's, the tips of the elevator are made from a plastic that gets incredibly brittle in subzero temperatures and is very prone to cracking. There are aftermarket fiberglass replacements available that largely solve that issue, so I've got no idea why Cessna still uses the stupid plastic parts on a $300,000 airplane.
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Dec 7, 2010 23:50
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