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Murgos
Oct 21, 2010


Godholio posted:

Just seats from one side to the other and a rope bridge over the top. This gets rid of those pesky overhead bins, too, so almost everything has to be checked for an additional fee.

How much pedal power does it take to move a turbofan at speed?

New from United: Fitness Class!

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Murgos
Oct 21, 2010


drunkill posted:

Major Wilfred McCloughry DFC, DSO, MC of No 4 Squadron Australian Flying Corps poses in front of the famous Sopwith Camel fighter aircraft.

I recall reading that the Sopwith Camel used castor oil as an engine lubricant and was extremely leaky such that the pilot would be inhaling a castor oil aerosol vapor for his entire flight. Castor oil is used medically as a potent laxative.

Murgos
Oct 21, 2010


Nebakenezzer posted:

Can I ask a question relating to R101?

I found a description of R101 "chief engineer" Lt. Col. VC Richmond as "an enthusiast of lighter than air flight - not really trained as a engineer - a good manager of men."

First question: does this surprise anyone?

Second: Is this in any way typical of older aerospace projects? Because I guess I thought like it is today would be like it was, IE the person in charge of engineering decisions would be an engineer, abet one now acting as a manager.

I'm just kind of curious why you think someone who attended University at the Royal College of Science and worked as a young professional doing structural analysis for one of the largest engineering firms in London at the time isn't actually capable of doing engineering work?

"Not really trained as an engineer" isn't saying much. Our VP of Engineering isn't really trained as an engineer but his PhD in physics and 40 years of experience is a pretty good substitute.

Murgos
Oct 21, 2010


Linedance posted:

Lol I see it now. That's not even how it works, you clip that to the ground stud on the gear!

Since the truck he's strapped to has rubber tires he's not even actually grounded unless it has it's own separate grounding strap.

Murgos
Oct 21, 2010


Plinkey posted:

If you work in the industry or a related one it really makes sense when you see the man-hours and paperwork that go into every-single-loving-part and component.

Electronics are the worst offenders (military side), most aircraft radar cpus probably run at something like 500mhz-1ghz tops and use 10 year old technology because it was all custom made and way more planning/effort went into it's manufacture per part then the motherboard/ram/computer you're typing on right now. The poo poo has to work 99.99% of the time and you need traceability incase something breaks

99.9%? You're off by orders of magnitude.

I just reviewed reliability analysis (mil-std-217f) for a complex box thats upwards of 800,000 hours MTBF. Yes, that's right, 91 years between failures. Not one of the components, the whole system integrated together.

Some individual components are rated at over 30,000,000 hours...

Murgos
Oct 21, 2010


Cat Mattress posted:

When LockMart got the F-35's computer to crash only every ten hours instead of every four hours as before, the USAF said "okay, cool, good enough, we'll accept it like that"

You're conflating the failure rate of the electrical system with the failure rate of the software. Those crashes aren't caused by components blowing apart or transistors getting stuck open.

I made no claims about software.

Murgos
Oct 21, 2010


Wingnut Ninja posted:

Navy dunker training is a four-year qual. I was talking with some friends about it the other day, and I think the main thing that it teaches isn't so much specifically how to get out of an aircraft (since the trainer is a generic box with seats), but more of an expectation of just how loving confusing everything is when it's upside down, pitch black, and full of water.

I did it three times in 6 years, I think? Once in boot camp (or AWT?), once getting ready to float with a MEU and then once again just before I got out because I guess time was up? I don't recall.

The first one was in a Huey and then the other 2 were in ch-47ish mock ups. It was kind of fun but we never hit the water very hard and weren't in full combat gear, I would expect that reality would be much worse.

Murgos
Oct 21, 2010


hobbesmaster posted:

You usually can't bring your own alcohol to consume into a bar or restaurant either.


wolrah posted:

You usually can't bring your own food or drink in to a bar or restaurant in any way...

Am I missing something? Because bringing alcohol into restaurants that don't serve, or have 'bottle service' is totally a thing and so is bringing food into bars that don't have a kitchen.

Murgos
Oct 21, 2010


Enourmo posted:

That's the key. Your example doesn't apply because airlines do serve alcohol.

No, corkage fees and bottle clubs are also things that exist. Except for that obscure and apparently mostly ignored regulation I am sure airlines would happily charge you an enormous fee to let you drink your own alcohol on board.


e: VVVV Have you ever been on a Grey Hound? Trust me there is no shortage of passenger procured alcohol (among other substances) on board.

Murgos fucked around with this message at 11:59 on Jun 9, 2016

Murgos
Oct 21, 2010


Lightbulb Out posted:

Are you coming during the air show?

<insert masturbation joke here>

Murgos
Oct 21, 2010


Mortabis posted:

The US-2 is rated for 3 meter waves.

That's pretty impressive. Like full operation take off and landing in 3 meter waves? Or, just "If you find yourselves in rough seas don't panic just yet and wait it out."?

3 meters isn't enormous but even old salts would rather not be out in anything not truly ocean going in it.

Murgos
Oct 21, 2010


Nebakenezzer posted:

So have you ever heard of the Supermarine Nighthawk? It was a purpose-built interceptor - of Zeppelins.
This aircraft was brought to you today by Good Idea/Bad Idea.

Murgos
Oct 21, 2010


Gervasius posted:




Four K-13 (AA-2) rocket engines strapped to a FAB-250 bomb. Mounted on a truck.
I hope that worked the way I expect, spiraling ludicrously out of control until impacting and breaking into 1000 pieces with the bomb exploding some random amount of time later.

Murgos
Oct 21, 2010


In my experience even Arab Muslims aren't generally all that observant of the restriction on alcohol.

Murgos
Oct 21, 2010


hobbesmaster posted:

Thats cheaper than spirit.

It costs more to fly the carry on than to fly the person.

Murgos
Oct 21, 2010


The range they are doing the stunt at would have a review board and safety requirements.

E: not to mention the FAA, Fox execs and their insurance partners. There is at least 5 groups supervising something like that.

Murgos fucked around with this message at 19:27 on Jul 31, 2016

Murgos
Oct 21, 2010


Inacio posted:

Is... is that really feasible? Would be pretty awesome to have long range vehicles (flying or not) by using a small traditional engine to generate energy. But I assume that it isn't very efficient

Using a gas or diesel engine to power an electric motor is very efficient (energy wise) and works really well. Pretty much every large ship or train uses this scheme (more recently hybrid cars). But while it's energy efficient it's not size or weight efficient.

Size + Weight usually is trumps in aerospace.

Murgos
Oct 21, 2010


Linedance posted:

It always comes down to this though. Why lower your efficiency and add complication by creating a system where the liquid fuel combustion engine turns an electric motor which turns the propulsion mechanism, when you could just directly power the propulsion mechanism from the combustion engine and do away with the middle man? You could still run a secondary independent emergency battery or ram air combination electrical drive as backup in case the combustion engine fails. In fact independent would be the better way of doing it from a safety perspective.

High end well designed diesel-electric and diesel-mechanical systems both come in at the 95-97% efficiency range.

The issue is torque. An electric motor applies it's full torque output all the time. Even at 0 rpm, if you look at the torque curve for an internal combustion engine you will see that this is not the case. That there is a peak torque output at some rpm value. This is obviously really important when you have a heavy train or huge ship trying to get moving from stopped.

I don't think that's as important for aircraft engines though. They can pick their most efficient rpm and just stay there most of the time.

If batteries improve dramatically though there will be a case for all electric engines in aircraft just due to fuel efficiency concerns. $ per kW is much, much lower at a big power plant than any portable engine can hope to be.

Murgos
Oct 21, 2010


Dannywilson posted:

This was inside a sealed LRU, panels are one thing, but this took taking the LRU out, then like 7 or 8 screws to take the thing apart. HOW DID THE CHIPS GET IN THERE.

This is still mind boggling to me like 15 years after it happened.

They were in there from assembly? Or, the last time it was refurbished.

These are high tech, high skilled workers. Imagine whats in the panels of your car or house... I've seen like, half a case of beer get left in the spaces between drywall framing and I've only been to a couple of construction sites.

Murgos
Oct 21, 2010


evil_bunnY posted:

Someone still has to provide the firing solution, and when you put "multispectral sensors", good engines and a maneuvering airframe on a AUV you won't buy 4 of them for the price of a raptor.


People tend to overlook that the person in the loop is a degree of fault tolerance. It's pretty important really and actually turns out to be much, much cheaper most of the time than adding in a degree of fault tolerance with more redundant hardware/processing.

Murgos
Oct 21, 2010


Alereon posted:

I think that because of improvements in the performance, cost, and size/weight of computer electronics this is no longer true.

Nah. It's trivially easy to spend a couple of hundred million dollars on fault tolerant software for systems with very little complexity at all. The hardware is getting cheaper but by the time you've established the pedigree of your parts and processes the number of zeros involved still gets to quite surprising levels.

Computers are good at evaluating problems that can be identified and processed as discrete inputs. Most cases where the word 'fault' comes into play don't fit those categories. Kind of by definition you are dealing with systems not working correctly and not telling you the truth. Computers have hard problems with liars, particularly when they may be the one lying.

Murgos
Oct 21, 2010


Alereon posted:

Just to be clear, I am in no way suggesting that it would be feasible to replace the pilot of an existing airliner with a computer and have it operate safely and reliably. I am saying that if you are designing a new aircraft and want it to be safe and reliable, it doesn't make sense to intentionally include a human pilot. A key point here is the cost savings from not building an aircraft that carries a human. If you already have to carry people that goes out the window.

This is nonsense. You're making the claim that autonomous aircraft are safer and more reliable except for the case when they have to be safe and reliable.

There are lots of somewhat autonomous drones out there but the tasks they do are for the most part carefully constrained not to be a danger (or the aircraft is so small as to be not dangerous) and have a minimal cost for being unreliable.

Real tasks, that have to be successful or operate in an way that could endanger people and/or incur large financial costs for failure are not currently suitable for drones because drones are not safe and reliable (unless you spend vast amounts of money to make them so).

Murgos
Oct 21, 2010


Nostalgia4Infinity posted:

looks like a plane to me

Looks like a flipper armed superman with a too-big cape to me. You know,. the way kids stick their arms out to pretend to fly?

Murgos
Oct 21, 2010


Mortabis posted:

I very much doubt they would be able to re-use stolen flight control software. Besides which, the fly-by-wire software is not the hard part of the F-35 software development.

Hard part? No because we solved the problem of electronically compensating for inherently unstable platforms in the 70's/80's (thanks in part to that Neil Armstrong guy again). Significant cost driver? You betcha.

Murgos
Oct 21, 2010


xergm posted:

Basically, it's an encrypted link that can carry all sorts of things. It's great for situational awareness, because a bunch of fighters can each share their radar picture with each other, and share targets.

https://en.wikipedia.org/wiki/Link_16

Everything any nerd would ever want to know about link16:

http://www.northropgrumman.com/Capa..._Networking.pdf

Fun fact the link 16 specification clocks in at ~10k pages.

Murgos
Oct 21, 2010


Platystemon posted:

Government contractors are the worst. You have to specify everything or they’ll deliberately do the wrong thing and bill you to change it. You can’t leave anything to common sense.

The thing about link 16 is that there are a lot of vendors from a lot of counties and all the radios have to talk to all the other radios. US Navy radios have to talk to RoK Army for example. Every implementation is different but they all need to interoperate so you get insanely detailed docs.

Murgos
Oct 21, 2010


CommieGIR posted:

Just now noticed. But you forgot MIDS JTRS/LVT

I mean, technically its the same thing, but I just wanted to be part of the party

Sort of the same thing but not? In that it inter-operates with L16 but is completely different internally.

I think MIDS and LVT refers to the host terminals you can connect to and that you can use it in a MID System, JTRS is that it's the SDR version of the radio developed that is compatible with the JTRS SCA Spec.

Yeah, it's alphabet soup. Cool system though.

Murgos
Oct 21, 2010


Careful study of that video is probably worth a half semester of fluid dynamics.

Murgos
Oct 21, 2010


Mortabis posted:

You're looking at a lot more than 4x the price I'd wager.

The article quote was same price as international business class. Which is 4x-8x (or more depending on route) peon class already.

Murgos
Oct 21, 2010


Platystemon posted:

It depends.

Describe your skin tone on a scale of #FFFFFF to #000000.

#00FFFF

Murgos
Oct 21, 2010


Dannywilson posted:

He's talking about Romania (another popular to-from the sandbox stopover) wrt the guards having SMG's.

When we were flying from US to Somalia in December '92 we stopped in Rome to refuel (we were on a chartered 747). The Italians decided that they had to keep an eye on us (in formation on the runway for 4 hours) with their riot control police. APC's, full body kevlar'd dudes in black with SMG's, the whole works.

I never quite understood what they were thinking.

Murgos
Oct 21, 2010


Everyone knows that when the tank says E there's always a gallon or two left.

Murgos
Oct 21, 2010


Ola posted:

Haha, 248 * 24 * 3600 = 21427200, so if it's counting something 100 times a second it overflows a 32-bit integer. Sure you can just reboot it once in a while, but I don't think there's any aeronautic engineering reason for not writing that bit of code better. It makes it look like a stupid airplane and you wonder what other else is lurking in there.

No. There is almost certainly a requirement that the GCU be able to operate nominally while powered on for X days. The coder met the requirement and probably exceeded it by two orders of magnitude( at a guess).

If you want to levy the requirement on the system that it shall be able to operate nominally when powered on indefinitely you can probably ad a bunch of zeros to the cost. This is almost certainly a case of where a counter roll over is being read by lots of other systems that are built concurrently by other parties and you have to draw the line somewhere.

e: The 'shall operate for X days while powered on' is a common requirement and is almost always specifically used to make sure counters don't roll over during the expected period of operation which is generally much larger than the actual use case being considered. I've seen it in at least half a dozen different systems.

Murgos fucked around with this message at 14:50 on Dec 5, 2016

Murgos
Oct 21, 2010


Davin Valkri posted:

Wouldn't that both (a) be freakishly expensive and (b) put classified technology and material into nominally private, non-government-controlled concerns?

What part of Donald J Trump is it that you don't understand?

Murgos
Oct 21, 2010


What does Sully do these days?

Murgos
Oct 21, 2010


Sagebrush posted:

well see there's this thing called the Sunk Costs Fallacy

Sunk costs fallacy is that you feel compelled to continue something just because you started it even though an alternate approach would be more beneficial if you changed.

The F35 still has an enormous potential and I am not aware of an alternate path that would actually perform better or be cheaper if we switched to it.

Murgos
Oct 21, 2010


hobbesmaster posted:

Trains are ok though.

That bit on the ice? Eh, not so much.

ITT parents of small children out themselves.

Murgos
Oct 21, 2010


I can say what would happen to an f-35 if there was a single event upset to a flight control. Nothing. It's a triple redundant system. You would have to have two simultaneous seu to the same fault with it a very small time (ms) window to see something like that.

Murgos
Oct 21, 2010


Generally looks a lot like the nose on a modern jet airliner to me.

Physics being physics I guess.

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Murgos
Oct 21, 2010


Keith Atherton posted:

Is "Airplanes I've flown on" a topic that is thread-worthy?

I just made a list but I don't want to derail

Edit: Sorry - back to lurking

Probably depends on either how interesting the list is or if it's crazy long.

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