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priznat posted:On the plus side in this makes sense since I keep seeing contracting postings for Petawawa
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Jul 3, 2014 05:20
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news I read that the delivery of the last CH-147F chinook of an order of 15 just happened on time AND on budget, holy poo poo.
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FullMetalJacket posted:this makes sense since I keep seeing contracting postings for Petawawa For maintenance?
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Jul 3, 2014 05:24
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Correct. Most of the time they're specific and mention "previous ch-146 experience an asset" likewise for postings at Gagetown, but before I went off to QC I had a few calls to go to Ottawa to work on a "research project". A firm in the Ottawa valley had a lot of involvement in developing the silencers for the Chinook, So I suspect the two were related in some regard. Shame they didn't like my level of experience. 
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Jul 3, 2014 05:31
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Plastic_Gargoyle posted:This was a semi-serious proposal for a B-1R variant... It's like you guys have never read Dale Brown...
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Jul 3, 2014 09:51
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Pretty bird landed at the airport today. Only a few months late. 
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Jul 3, 2014 11:42
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Linedance posted:Pretty bird landed at the airport today. Only a few months late. What is that?
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Jul 3, 2014 11:49
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I'm gonna guess that's a 787.
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Jul 3, 2014 12:11
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RandomPauI posted:What is that? 787 winglet 
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Jul 3, 2014 12:17
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787? E: Durp
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Jul 3, 2014 12:17
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From what I understand, the reason that modern jetliner engines look like an engine wearing a "collar" is because they're high-bypass turbofans: most of the thrust comes not from squirting hot exhaust gases out of the engine's rear end, but from the huge primary fan discs driving air around the engine which improves efficiency and noise. The previous generation of jetliners was big on trijets - 727, L-1011, DC-10. The #2 engine on these always seemed like a big compromise in placement, and I don't see how they could have effectively used the high-bypass concept on those. Was there some ingenious engineering done, or was high-bypass not appreciated/perfected in their era?
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Jul 3, 2014 14:40
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This is out of my rear end, but I'm guessing 4 major things: 1) Improved metalurgy: Fans are big, have insane centrifugal forces and need to be light 2) Improved manufacturing technology: can build the more complicated gearing to keep the fans and compressors in synch 3) Improved experiential and experimental data: wind tunnels,bitch 4) Change in demand and priorities of airlines: gas is expensive and noise laws are getting more draconian every year.
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Jul 3, 2014 14:47
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The DC-10 and L-1011 were high bypass. I don't understand why their #2 engine position would contradict that. The 727 had low bypass turbofans. Low bypass gives you better power-to-weight ratio and better high altitude performance. High bypass are costlier to make, but are more fuel efficient and deal better with hot-and-heavy takeoffs E: hot-and-high, I mean, obviously simplefish fucked around with this message at 15:41 on Jul 3, 2014 |
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Jul 3, 2014 15:14
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hogmartin posted:From what I understand, the reason that modern jetliner engines look like an engine wearing a "collar" is because they're high-bypass turbofans: most of the thrust comes not from squirting hot exhaust gases out of the engine's rear end, but from the huge primary fan discs driving air around the engine which improves efficiency and noise. The previous generation of jetliners was big on trijets - 727, L-1011, DC-10. The #2 engine on these always seemed like a big compromise in placement, and I don't see how they could have effectively used the high-bypass concept on those. Was there some ingenious engineering done, or was high-bypass not appreciated/perfected in their era? As you probably already realise, the DC-10 and L-1011 were indeed high bypass on all the engines. Here's a photo that demonstrates how the Dc-10's #2 engine is configured (and shows it's high-bypass) 
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Jul 3, 2014 15:46
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Its easy to see on the DC-10 but I think the question was more about the L-1011 because it seems kinda crazy to hide a high bypass engine in there. But the answer is that they did and that the L-1011 owned.
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Jul 3, 2014 15:51
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hobbesmaster posted:Its easy to see on the DC-10 but I think the question was more about the L-1011 because it seems kinda crazy to hide a high bypass engine in there. Yep, I think that's the sort of thing I meant. Looking at the straight-through #2 on the DC-10 I can (convince myself that I can) see the bypass ducting, but the #2 on the L-1011 is such a goddamn aeronautical crazy straw that I just can't picture it.
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Jul 3, 2014 16:21
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Actually if you look at the back of a 1011 the bypass is very clear http://en.m.wikipedia.org/wiki/File:LockheedL1011.jpg
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Jul 3, 2014 16:28
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hogmartin posted:Yep, I think that's the sort of thing I meant. Looking at the straight-through #2 on the DC-10 I can (convince myself that I can) see the bypass ducting, but the #2 on the L-1011 is such a goddamn aeronautical crazy straw that I just can't picture it. It helps once you realise that the engine is at the tail end of the S-duct, after the twist e: this image makes it clearer (small image tho): 
SybilVimes fucked around with this message at 16:31 on Jul 3, 2014 |
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Jul 3, 2014 16:29
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Also, while on the subject of Lockheed's defunct commercial division... It seems they may be contemplating getting back into the airliner segment, and that this is a real proposal:  Odd, but it'd be nice to see some 'unique' airliners that aren't just a 'tube, wings, 2 engines on pylons' again. Also, some bonus weirdness I came across... 707 with rarely used quantas cargo pod (and a nice view of the original hush kits for 707s)  And a L-1011 in engine-ferry configuration (this isn't a photoshop, however much it looks like it, this is a legit way the tristar could be configured): 
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Jul 3, 2014 16:35
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You get 5-engine 747s in the same vein (the 5th engine is unpowered and being ferried)
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Jul 3, 2014 16:39
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SybilVimes posted:Also, while on the subject of Lockheed's defunct commercial division... With that much bypass shouldn't you just use prop fans? (RIP crazy DC-9 derivatives)
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Jul 3, 2014 16:58
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simplefish posted:You get 5-engine 747s in the same vein (the 5th engine is unpowered and being ferried) 
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Jul 3, 2014 17:01
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DC-10 can do it too: Related: Since even a nose-load 747F can't carry a fully assembled GE90, (Only the AN-124, AN-225, and C-5 can swing that,) the GE90 fan is designed to be detachable in the field, so that you can load the engine core, and then lay the fan section down flat on the load deck of your everyday 747F or 777F, when you have a grounded 777 somewhere that doesn't also have a quickchange-ready GE90.
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Jul 3, 2014 20:47
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Airbus wants to get rid of the traditional cockpit so they can shape the noses of planes more aerodynamically by not having to worry about glass or visibility. http://arstechnica.com/gadgets/2014/07/airbus-submits-patent-application-for-windowless-jet-cockpit/
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Jul 3, 2014 21:06
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bull3964 posted:Airbus wants to get rid of the traditional cockpit so they can shape the noses of planes more aerodynamically by not having to worry about glass or visibility. Not a new concept.
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Jul 3, 2014 21:28
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So, are these attachments just....there, or they added as the need arrives?
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Jul 3, 2014 21:34
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bull3964 posted:Airbus wants to get rid of the traditional cockpit so they can shape the noses of planes more aerodynamically by not having to worry about glass or visibility. I would be really, really nervous about that as a regulatory agency.
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Jul 3, 2014 21:36
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wdarkk posted:I would be really, really nervous about that as a regulatory agency. The thing is though, most modern planes have no physical linkage between control surfaces and the cockpit anyways. So, I'm not really sure how moving to virtual displays really hurts things. You already have the critical control aspect of the play relying on electrical signals and computers, surely the display aspect could be made just as robust.
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Jul 3, 2014 21:44
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e- never mind I'm tired and not talking any sense.
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Jul 3, 2014 21:48
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Is that ever done on passenger flights?
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Jul 3, 2014 21:52
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^^^ is what ever done? Fly by wire is on the A320 and newer airbus and the 777/787Linedance posted:I honestly don't think the stumbling block here is the plane, it's the airports. The plane can know everything about itself and where it is in space and on the earth, but it won't know there's goats on the runway. That's what cameras are for. Large modern jets already have a bunch pilots can look at. Important for ground handling and the like. hobbesmaster fucked around with this message at 21:56 on Jul 3, 2014 |
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Jul 3, 2014 21:52
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SybilVimes posted:Also, while on the subject of Lockheed's defunct commercial division... I can't find the post but I swear I made fun of the ever-enlarging winglet trend by suggesting someone just make wings that just keep going up and form a big hoop. It appears someone at Lockmart had the same idea but took it seriously.
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Jul 3, 2014 23:39
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bull3964 posted:The thing is though, most modern planes have no physical linkage between control surfaces and the cockpit anyways. So, I'm not really sure how moving to virtual displays really hurts things. You already have the critical control aspect of the play relying on electrical signals and computers, surely the display aspect could be made just as robust. Also adds the possibility of looking 'through' the cockpit. That'd be a big safety advantage over traditional cockpits (imagine if QF32's crew could have just looked through the cockpit's walls and seen the damage straight away?).
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Jul 3, 2014 23:50
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bull3964 posted:The thing is though, most modern planes have no physical linkage between control surfaces and the cockpit anyways. So, I'm not really sure how moving to virtual displays really hurts things. You already have the critical control aspect of the play relying on electrical signals and computers, surely the display aspect could be made just as robust. I would expect the majority of the airgoing public to have a visceral bad reaction to the pilots not having a window to look out of, not really understanding that they fly by instrument for the majority of the flight anyways. That will probably kill this concept faster than any regulatory agency's refusal to sign off on it.
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Jul 3, 2014 23:53
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Geoj posted:I would expect the majority of the airgoing public to have a visceral bad reaction to the pilots not having a window to look out of, not really understanding that they fly by instrument for the majority of the flight anyways. That will probably kill this concept faster than any regulatory agency's refusal to sign off on it.
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Jul 3, 2014 23:58
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Psion posted:I can't find the post but I swear I made fun of the ever-enlarging winglet trend by suggesting someone just make wings that just keep going up and form a big hoop. It appears someone at Lockmart had the same idea but took it seriously. The box-wing design has been floating around as a concept aircraft since the 50s. Never a production aircraft though, we'll see if the efficiency increase is worth it.
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Jul 4, 2014 00:00
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Previa_fun posted:The thread title got me thinking about the su-34. When was the last time you took a poo poo at mach 0.8 and +7g. Having the other guy pull 7Gs while you're on the shitter is probably a pretty effective way to deal with constipation.
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Jul 4, 2014 00:05
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Psion posted:I can't find the post but I swear I made fun of the ever-enlarging winglet trend by suggesting someone just make wings that just keep going up and form a big hoop. It appears someone at Lockmart had the same idea but took it seriously. Given that the engines are suspended from the upper wing surface, at the rear, they're getting all the benefits of fuselage-mounted engines, without the vibration/noise issues. Only thing I can't tell at first glance is if the AOA problems of a T-tail kick in, or if it's 'ok' because you have so much wing area and your control surfaces are all going to be elevons anyway - so deep stalling of elevators shouldn't ever be an issue. It might be a genius design that combines almost all advantages of each option...
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Jul 4, 2014 00:07
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Psion posted:I can't find the post but I swear I made fun of the ever-enlarging winglet trend by suggesting someone just make wings that just keep going up and form a big hoop. It appears someone at Lockmart had the same idea but took it seriously. Look up "non planar wings" and you'll see some actual flying versions from over the decades, plus this thing: 
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Jul 4, 2014 00:07
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benito posted:Look up "non planar wings" and you'll see some actual flying versions from over the decades, plus this thing: That's a photoshop. This isn't https://www.youtube.com/watch?v=X6A1mSh0DB8 There are lots of reasons why they're not a great idea. Mainly control placement and that they stall like a mo-fo (like ducted fan ducts do). The main advantage to them is that they have double the spanwise lifting efficiency, but hey, they're essentially biplanes. Of course they have double the spanwise efficiency. They lifting efficiency vs area is very similar to a conventional wing. So they're good when you need a small wingspan and don't want a traditional biplane for some reason. The swept-box wing design (which has been around forever) counters these problems and gains the advantages/disadvantages of a canard configuration, but I think that currently the weight of the structure offsets any gains, so they're waiting for advances in materials to become a reality. edit: VVV- your sarcasm was a bit subtle in text form. Apologies. You could stack them in a hexagonal-cell multi-story hanger with greater packing efficiency maybe? Captain Postal fucked around with this message at 00:38 on Jul 4, 2014 |
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Jul 4, 2014 00:28
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Captain Postal posted:That's a photoshop. Of course it's a Photoshop, hence my qualifier. But can you imagine the hangar for that thing?
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Jul 4, 2014 00:33
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