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Elviscat
Jan 1, 2008

High Energy, Good Feeling!




If y'all haven't seen, Iran now has an SSG to compliment their fifth-gen stealth fighter https://www.aljazeera.com/amp/news/...7061811732.html

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Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Previa_fun posted:

So would these either:

1.) Rip the track out of the ground and lose control

or

2.) Stay attached and immediately nosedive into the ground

or

3.) Remain attached to the track and controllable.

I think the real question to ask is "what kind of diamond-brilliant intellect does it take to conceive a replacement for a boring, safe, and efficient mode of transport, and make it slower, more lethal, and less efficient all in one go?" "What would it take to combine all the worst aspects of a plane, train and helicopter, without using the obvious answer of 'flimsy gondola suspended from explosive/irreplaceable lifting sack (aaaaaand poo poo, at least those are efficient)'?"

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




CommieGIR posted:

Plus Boeing leaving tools and FOD in the USAFs new KCs just seals the deal.

This is just a tried and true Defense Contractor tradition.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Sagebrush posted:


If it turns out to be a problem with the sensors or the MCAS, Boeing is hosed.


But Boeing has admitted this is a problem(ish) and provided additional training on the exact issue and how to recover from it to airlines? Certainly every 737MAX pilot must be aware of it after the Lion crash.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




1 of 1 redundancy (i.e. no redundancy) is probably not allowed on flight critical systems.

Coming from a whoooole 'nother engineering field though, so ymmv.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




I finally made it to Udvar-Hazy, it's insanely overwhelming. Just walking on the promenade and seeing two of the fastest, highest-flying vehicles ever made...

https://i.imgur.com/Sc61Ku9.jpg

Then there's something for everyone:
Biggest engine ever made




Big planes



Small planes



Space planes



Leaky planes





Rocket-assisted suicide planes



Really efficient rotary-wing suicide planes



Big wastes of time and money.





Bullet Missile with Butterfly Wooden wings.



Something for LTA travel "enthusiasts"

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




That's a real mic drop from WOW, should we wind down operations? Nah, gently caress it we're out

Elviscat fucked around with this message at 18:00 on Mar 28, 2019

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




pthighs posted:

I agree friend, you and I were meant to break Mach 1 straight up, and caress the face of God herself.

Felix Baumgartner parachute account spotted.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Fender Anarchist posted:

Military jets are primarily known for their maneuverability, though, and the pilot has an exit in case something goes wrong; lower risk, for an actual reward (unstable planes are more maneuverable). A plane with 100s of passengers whose primary task is "fly in a straight line efficiently" has zero reason to be designed with negative stability.

Aside from stubbornly maintaining a 50 year old type certificate despite massive design changes like that.

There are some sweet overreactions ITT, the 737 MAX is not inherently unstable like an F-16, it suffers from a programming flaw.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




evil_bunnY posted:

It's missing 2 AoA sensors and a safety critical flight control software. And because the software wasn't deemed safety critical by the people who sell it, they didn't even catch the basic bitch input sanitization mistake they put into it.

I 100% agree, Boeing designed in a system that they decided wasn't flight critical, but which will fly the plane into the ground on a single point failure, from my understanding it doesn't even cross-check the two installed sensors and deactivate if it sees an out of tolerance deviation, like you would expect a non flight critical "pilot aid" feature to do, much less satisfy the 2/3 redundancy you would expect from ANY critical engineering system. It's a fatally flawed system, the current also flawed safety certification scheme failed to catch it, and seems to have actively contributed to the design of the system.

I'm not in the aviation industry, but I'm in an engineering field where safety in design and operation can not be compromised, so I like to come to this thread, because of the high-quality posting from Patagonian Cave, Fingerprince Et al who allow me to understand what's going on well, without the background noise of, say, YouTube comments.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Well, fortunately Aluminum is a really good conductor, so it'll conduct all them 'trons safely around the delicate meatbags in the plane, same reason/misconception for why you're safe in a car, you're not really in the flowpath, not that rubber does poo poo all to protect you.

I heard the new composite super-planes have a conductive mesh embedded in the composite to provide this effect, us that true?

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Keeping Chrome Dome going after the first few of the 41 for Freedom were launched is a wonderful example of the power, and hubris, of the SAC in that era.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Isn't anything that flies, and has a wing a flying wing?

E.g.: an bumblebee

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




RandomPauI posted:

Thank our godless state laws for mandatory fire sprinklers.

I don't think the sprinklers actuated so much as the plane smashed right through the pipe, there was a huge waterfall in the video on the morning news.

And thank goodness it was low/out of fuel, that would've been a fireball and a bunch of people would have died otherwise.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




The Army wanted in-house cargo airlift support, got it in the form of the C-27, Air Force "won" an inter-service pissing match about who gets to fly fixed-wing aviation assets (everyone except the Army), so the Air Force got the C-27s that the DOD had already purchased, but didn't loving want them because they already have a massive fleet of C-130s/17s/5s that they can't afford to keep in the air, so the Pentagon is desperately searching for someone to GIVE the things to, before 60 Minutes does a special on the program.

It's the politics of the largest organization, with the most money in the world, an array of government contractors hanging off their teet, kickbacks, blowbacks, and rampant greed and corruption.

E^^ it'd have to be water bombers.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




BIG HEADLINE posted:

I know the reason against something like this would be $$$ and "what if it goes wrong," but it'd be nice given the recent spate of "depressurization as a tool for crazy/depressed pilots" if they'd put in a logic gate that only allows the plane to be depressurized after being pressurized once weight is reapplied to the landing gear after landing.

It certainly wouldn't stop another Germanwings-type incident where the nutjob in question doesn't care about hearing the screams behind him, and I could see it delaying some flights if/when it malfunctions and the plane has to be manually depressurized on the ground...

Thoughts?

Or add another few thousand lines of code to the satellite tracking systems mentioned in that article so that when a plane undergoes depressurization at altitude it constantly broadcasts an automated distress call until someone's forced to investigate.

I think airplane manufacturers might be wary of any system that the pilot can't directly control/override in light of recent events. In any case there's no technological solution, besides fully autonomous aircraft.

There are a lot of fields out there where you avoid seeing mental health professionals at all costs, and there are definitely cases where SSRIs cause mental "breaks" and paradoxical effects that can aggravate the condition, which is the worry and the reason for some of the backwards regulations on flying while taking them. It's sad, and it requires a full culture shift, where pilots are encouraged to spend (paid) time on the beach to get their heads/meds right. The Western world is kinda slowly shifting to realizing that mental health is not something you can just take a concrete pill for and "harden-up" and manly-man your way through, but we're still not there, and I imagine it'll take even longer for less progressive cultures to realise this.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Aargh posted:

On the flip side is there any reason to fly lower level on a 380?

So you're not tortured by the idea of being behind the thing's hideous fivehead the whole time?

Elviscat
Jan 1, 2008

High Energy, Good Feeling!





He was clearly trying to ditch the pursuing fighter with the maneuver at 1:15 in this video. https://youtu.be/Jv1ZN8c4_Gs

Elviscat fucked around with this message at 03:13 on Jun 25, 2019

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




I thought that more than a few minutes above FL30 was sure hypoxia and death? Could some of those CNN numbers be from propeller planes or pressurized cargo holds?

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




NightGyr posted:

We learned that it's simpler to just heat the air directly. And instead of a boiler, we use a turbine... and voila jet engine.

A Nuclear powered prop driven airplane is my fetish though.

And totally doable with molten salt reactors.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




bull3964 posted:


This is the exact wrong attitude to have. "We tried to do something bad with the bugs that were handed to us and we couldn't so everything is good." The correct answer would be "We determined that the vulnerabilities pose no thread to flight safety but we are undertaking steps to close those vulnerabilities and reviewing our testing procedures to ensure similar vulnerabilities aren't created in the future."

So, it's not a "sky is falling" type of thing, but you don't just shrug stuff like this off either. You take steps to close the issue and review how it became an issue in the first place.

This is totally true from an engineering perspective, but from the corporation you can't ever say this, because tomorrow's headlines are "BOEING ADMITS TO POSSIBLE CYBER VULNERABILITY!" 'Will the next airplane YOU ride on be crashed into a mountain by hackers?' Call it a cultural problem or whatever, even in this thread there's been some gross hyperbole about the MCAS issue.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Sagebrush posted:

*battery-electric, I should say. We could build a DC-9 with a nuclear reactor powering a pair of electric propfans tomorrow if only the dang gubmint would allow it

Unfortunately Nuclear powered aircraft are a terrible idea, for pretty much every reason

Nuclear powered rigid airships though? You could use the hydrogen and alpha emissions to recharge your lifting gas! Mount the gondola on top and reactor on the bottom, radiation field intensity decreases with the square of distance, very little shielding would be required, making for a lighter reactor plant! There's no downside!*

*There may be some downsides


Also, any reasonable energy policy would attack ships and aircraft last, as they're the most difficult target, but thanks to "environmentalists" being window licking loving morons, nearly as bad as their lignite-worshiping counterparts we'll never have a reasonable energy policy in time and the world's gonna loving burn for it anyways, so why not fly some more while it's cheap?

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Sagebrush posted:

On that note, incidentally, I learned recently that the prepper nutjobs like to try to get their hands on avgas because it has no ethanol in it and thus keeps longer in their underground bunkers

For fucks sake, ethanol free premium is widely available, and fuel stabilizer is both cheap and effective at minimizing hygrophillia and separation. Honestly, after seeing fuel lines in NY and NJ after hurricane Sandy, keeping a few hundred gallons of fuel on hand doesn't seem that crazy.

I would not keep diesel though, if you get a bad batch it's subject to bacterial contamination, which forms a disgusting, thick, foul film on the diesel that instantly plugs any kind of filter. I've had to exchange tens of thousands of gallons of it, and the smell from the discharge tankers makes an outhouse on a 100 degree day seem pleasant.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Nebakenezzer posted:

I agree that transportation is the hardest to make carbon free, with aircraft (that aren't airships) the most difficult thing of all. I think a smart CC policy would attack the low hanging fruit first, then move up to more difficult problems, tacking transport (assuming ships with molten salt reactors isn't low hanging fruit) last.


Makes my hydrogen fuel cells idea look pretty sensible, eh? Eh?

Knowing what a nightmare other nuclear powered aircraft are, I've only thought a little about this. I think that some sort of lower power reactor, like those (currently unbuilt) modular reactors people have been dreaming of could possibly be used to power an airship, but the weight of any sort of system like that would be huge compared to other options. That makes me think that the only way an airship like that could use nuclear is if it was stonk-ingly gigantic even by airship standards, so you could get your payload capability up to where the cost would make it useful.

Yeah, you'd want to use a molten salt reactor so you don't need a massive pressure vessel, then polyethylene and water to attenuate neutrons, since they tend to make other things both very brittle and very radioactive, then use mostly distance and a little lead to get your gamma levels down to acceptable levels. Until your airship gets struck by lightning and you have a giant hydrogen fire that's also spewing burning radioactive salts over a populated area, then you might have something of an R101 moment.

You could certainly use one of the nuclear powered ram-jet designs to power a conventional fixed-wing aircraft, but they tend to have some small reliability and fallout issues.

Nuclear powered shipping is obviously feasible, the US Navy has a couple good size nuclear powered vessels, and Russia has the nuke ice breakers, and they'd actually be cheaper to fuel than current bulk carriers, maintenance costs for anything nuclear are ruinous unfortunately, you'd also have to adopt a far higher level of automation than the current regulatory bodies will allow, but realistically everyone who currently holds an engineer's license for big ships could be taught to run one without a crazy amount of extra training.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




In the event of a water landing, retrieving the knife from your rectum prior to drowning may prove difficult.

Anyone who wears a harness close to water should have a knife on them.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




You really want to upgrade to the Titanium or Vulcan float plane, the Chicago Electric model is cheaper, but you have a 50/50 chance of smoking the electrics each flight.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Minto Took posted:

Watch Lockmart come out of nowhere with a new mid-sized airliner.

Oh man, this airliner might cost twice what every other one in the world does but it sure is.... why am I dizzy? I think the O² supply i....

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




I could see a major worldwide recession making civilian aircraft orders dry up pushing them into bankruptcy, and the shortage of credit forcing a government loan of some sort.

If the 737 issues somehow pushed them into bankruptcy in the absence of a recession, they'd, at worst, declare bankruptcy, reorganize, maybe sell off some businesses to competitors and VC groups, there's too much capitol potential just in the 787 line for the Boeing name to simply disappear.

I could see their DOD contracts being broken up between Lockmart, NG, and GD though, they're not particularly competitive in that realm anymore.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Cross post from PYF.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




It's probably not a great Cunnilingus technique either, my partner does not enjoy it when my head hits their crotch at mach 0.8.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Hey baby, do you wanna gently caress a DEATH CATHEDRAL?

'Cause my name's Victor.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Hey baby, can you fit 70,000lbs inside of you?

Then you must be a BUFF!

no, don't ask what it stands for.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




"Oh no, it's 281,000 lbs? Damb girl, you must be a thicc-rear end FRED!"

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Isn't e.pilot an actual commercial pilot? I don't think he wants to be all "look at m'dick I'm a pilot" but I think he's pretty much the technical authority on this.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Sagebrush posted:

Ultimately it's the swiss cheese model:



This is a standard model for understanding process risk. Engineering controls attempt to prevent the risks by engineering them out of existence. Administrative controls prohibit actions or decisions that increase the risk. Behavioral controls teach the user how to operate the system safely and correctly. When an error gets through all of those, it becomes an incident, and then you have physical barriers (failsafes, shields, etc) that try to stop the damage. If those too fail, you have a catastrophe.

In this case no single factor was entirely responsible for crashes, and changing any one would be enough to prevent them.

- The plane was designed with less than optimal handling characteristics in the first place. (engineering)
- There was not enough physical redundancy in the AoA system. (engineering)
- There was no standard warning system to indicate a failure in the AoA system to the pilots. (administrative/enginerering)
- The MCAS system was not designed with much thought put into its ergonomics or the consequences of its failure. (engineering/behavioral)
- The MCAS system and its effects on the airplane's flight characteristics was poorly documented. (administrative)
- The Boeing lobbyists managed to get simulator conversion training waived when it really should have been required. (administrative/behavioral)
- The training that was given, in the case of Lion Air at least, was probably insufficient in the first place. (behavioral)

Change any one of those factors and things probably would have been different. The people blaming the pilots for not disconnecting the trim are focusing on the "mitigate" step in the image above, where the error has already happened and it's now up to the pilot to correct it in the moment. It's true that that could have saved the planes; there were indeed dozens of cases of probably MCAS-related "runaway trim" with the 737 MAX before the two crashes, where the pilots disconnected it in time and flew the rest of the flight uneventfully. But focusing on mitigation ignores all the other factors that had to line up to let it get that far.

This is a great post, I'd like to address MCAS based on engineering principles alone as a safety system.

Redundancy should be baked into any life safety system anywhere, in my field how we address this is having either 2/3, or more commonly 3/4 redundancy.

Basically, let's say you have a minimum of 3 sensors, if 1/3 sensors trip a "bad" value (we're assuming one sensor is hosed from the start, in this case stuck at 0⁰ AoA, so 2/3 is all that's required to trip), a warning is displayed, giving the operator a chance to cut the bad value out of the loop and engaging 1/2 redundancy, this means if one of the remaining sensors registers a "bad" value (in this case an AoA approaching stall) the automatic safety feature actuates, again it sounds a warning concurrent with the actuation, giving the operator the ability to cut out the remaining bad value, along with the lone operational sensor, returning the safety feature (trim) to a default value (whatever it normally is during level flight) disengaging any automatic override and returning control to the operator, this shoul be controlling trim with the electric actuators as the normal method, with manual control as a backup.

Inherent in this system is a minimum of two independent computing systems, i.e. each sensor has one set of mechanical linkages and two electronic paths, this allows the operator to select away from a faulted electronic signal path.

Automatic safety features are critical to any modern system that is vital to maintaining human life, old-school full manual controls are too prone to operator error, and too slow, it's been born out time and time gain that automatic safety's beat out human responses 9 times out of 10, but this requires a properly designed system, and a safety system that's not covering for an inherent design flaw, as Sagebrush said. Anyone in a field of engineering critical to human life can tell you how the "swiss cheese model" (what Sagebrush posted) or "pyramid model" (wide base of redundancy leads to stability) are essential to preventing failure.

Operator training and control is the first layer of blocks in the pyramid, and the last piece of swiss cheese in the diagram, which is why it's unacceptable for Boeing to not provide training on their new poorly engineered system.

SeaborneClink posted:

join the navy, become a submariner.

In case anyone wondering he's not kidding, XBOX controllers are not used to drive submarines, but are used for a variety of critical functions onboard, because they're more reliable and cheaper than bespoke controllers and talk güd with windows computers.

The joysticks used to drive a modern submarine are like $50,000.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




LibCrusher posted:

I use a high quality but Chinese made keyboard/trackball that an American vendor repackages and rewires the USB into a DB-9 that only uses 4 pins. The most common failure point is where they soldered the original USB wires into the DB-9. The unit costs $3000.

Oh man, there was a scandal awhile back where some dude was taking cheap Chinese microprocessors and forging Motorola markings on them, then reselling them at a discount to a DOD approved supplier.

Xbox controllers though, no real reason to get them through supply, they're cheap enough that you can just hop down to Best Buy with the Chop's credit card and pick a couple up on open purchase.

Military procurement is loving insane in its wastefulness though, ask me about trying to get new tools, with the only descriptor being "roll, wrenches" is it metric wrenches? 2-4" fractional wrenches? Who loving knows! Once a year we'd be allotted funds to order poo poo from the Granger catalog, it was like loving Christmas come early.

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




Airplane manufacturing is like the one industry where huge corporations make sense, the R&D costs, startup costs for huge facilities, certification costs, the risk that you overlooked your generation's square windows/MCAS. There's a reason there's only two players in this market, and one of those players required multiple COUNTRIES merging their aircraft industries and pumping capital into making them competitive.

Now a massive dollop of additional governmental control and oversight is obviously warranted.

E: This isn't exactly new territory for Boeing, remember when they convinced regulators they didn't need redundant hydraulic systems, then had multiple crashes because of failures in those components, but the FAA couldn't figure out why, because the Boeing reps who had been invited to help were literally stealing the evidence and replacing the failed cylinders with good ones?

Elviscat fucked around with this message at 17:11 on Jan 19, 2020

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




PainterofCrap posted:

I'm trying to imagine a universe in which anyone would ever set foot on a 737Max again.

Perhaps I simply lack imagination.

Two Boeing 737's have crashed before, after the first crash Boeing "lost" the critical parts that were causing rudder reversal, leading directly to the second crash, people have been flying on 737s in the intervening 20 years after the problem was fixed. With the media attention on the MAX I'm pretty sure it's not going back in the air without being as safe as any other plane in commercial service, I wouldn't think twice about flying on one once the FAA and their European counterparts get done tearing it apart and certifying a fix.


Article I think I erroneously stated this was the 757 before, I was wrong.

E:

Platystemon posted:

Bring back in‐wing engines.

Oh gently caress yeah, Victor passenger jets for all, make sure the V-tail and death-cathedral cockpit gets added on too.

Elviscat fucked around with this message at 01:47 on Jan 20, 2020

Elviscat
Jan 1, 2008

High Energy, Good Feeling!




bull3964 posted:

It was the 90s where the current level of media coverage didn't exist and while I'm certain there was internal politics that caused that issue, there weren't emails from employees saying that they were "shocked if the FAA passes this turd."

The 737 also wasn't grounded for over a year over it either.

True, no emails, just literal theft of evidence.

If the FAA says "this plane is safe now" people will fly on it, and airlines won't give them a choice, the number of people connected/informed enough to give a poo poo will be insignificant.

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Elviscat
Jan 1, 2008

High Energy, Good Feeling!




BalloonFish posted:

Just to quibble - the Ju86R's engines were weirder than that; they were supercharged two-stroke opposed-piston diesels. They had two pistons in each cylinder, with compression/combustion taking place between them as they moved inwards, rather than one piston-per-cylinder horizontally opposed as on a boxer engine.

Jumo licensed the patents on their opposed-piston diesel quite widely in the 1930s and ironically that ended up significantly to the Allies' advantage. Napier built the Jumo 204 (the first in the opposed-piston series) in the UK as the Culverin, and then developed that into the bonkers Deltic engine with went into torpedo boats, minesweepers and locomotives. Fairbanks-Morse licensed the patents in the USA and expanded the design into the 38 8-1/8 Series which powered a lot of the later Fleet Boat submarines and continued post-war in both GUPPY and nuclear subs. The Fairbanks-Morse engine was in turn copied by the USSR and made by Karkhov where it became the standard Soviet locomotive diesel of the post-war era. The Soviets also more directly copied the original Jumo engines (with plans seized as war reparations) to be the basis of the engines used in the T-64 tank and some of its later descendants.

Oh man, that's a good post, we were still putting those giant diesel-juice spewing fuckers on Nuclear powered submarines in the 90's

Here's some mesmerizing gifs from the Napier Deltic Wikipedia page.


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