scarier

For what it's worth, I'm not particularly worried. My understanding is that the accident was caused by a combination of poor maintenance practices, inadequate preflight procedures, and possibly poor ground procedures by the pilots that led to them taking off with an inoperative pitot-static system. Modern aircraft can also get altitude data from GPS (as you noted), as well as inertial navigation systems and radio altimeters, and generally have redundant pitot-static systems (at least an alternate static air source) for these kinds of contingencies.

Surveillance radars have narrow beam widths in azimuth, but broad in altitude to allow them to quickly survey around them and get good enough awareness of where everyone is. There's always a trade-off between resolution and volume--some military tactical and approach radars have very precise azimuth and altitude capability, at the cost of scan volume/time. Mode C (and now, arguably, ADS-B) was the solution to this problem, allowing ATC radar to have both good position and altitude precision with an acceptable refresh rate, at a non-prohibitive cost.

You'd be surprised--unless your hypothetical binocular observer was really handy with stadiametric ranging, I imagine they'd be nowhere near a mile. They might be able to get a decent azimuth and elevation on a single aircraft, but that's a much different problem than determining position near-simultaneously for a hundred.

Fair--we've both seen different parts of the elephant. I agree that military flight training is extremely rigorous, but I'd argue that it's so broad it has to gloss over a lot of technical detail in order to focus on developing the skills and instincts that matter in combat.

Based on the videos and reports I've seen, most or all of these cases involve sensor operation outside of typical A/A and A/G workflows, where the type of detailed technical knowledge that the system designers have could be more useful than years of practical experience. I've heard (and told) enough sea stories to be skeptical of eyewitness testimony (not that I think the aircrew who reported seeing this stuff are lying, but I've been humbled often enough by my own fallible recollections), and none of the publicly available footage I've seen of these events strikes me as anything more than a confluence of sensor limitations and (very understandable) human factors.

There are a number of reasons I'm glad the government is running these kinds of reports to ground, but I think wildly credulous reporting (particularly the "I'm not saying it was aliens, but it was aliens" interviews by a handful of aviators, but even presenting advanced adversary technology as the sane middle ground) is blowing this way out of proportion. We're already taking it way more seriously than it deserves, and there are plenty of other alligators closer to the boat.

ATC probably thought they were giving a different measurement. Especially in older planes, systems aren't particularly well integrated, and most of the time you ask them what they're seeing because you can't check your own Mode C altitude in the cockpit and want to compare it to your barometric altimeter (and yes, they generally do use the same static source, but it isn't atypical for them to read differently).

Thinking about it more, I've never tried asking ATC for an altitude check specifically from primary radar. It may well be that the system isn't set up for it, even if it's technically computable to some degree. When I'm talking coarse, I mean an altitude spread at range that may be measured in miles.

They can via primary radar, but the default displays secondary radar information (the transponder interrogation) as it tends to be significantly more precise. Surveillance radar has very coarse altitude resolution.

Frankly, I think the reality is even less interesting than that. US military aviators are trained to be proficient systems operators, but typically (and, I want to stress, very reasonably) have little or no education in EM/EO theory, and don't always understand the assumptions that engineers baked into these systems to optimize them for their primary use cases (which, in the case of targeting pods, is identification and targeting of surface objects--air-to-air capability was something of an afterthought). Knowing a little bit about how these systems work, I think it's pretty obvious why targeting pods wouldn't be able to focus properly in these kinds of circumstances, and how their built-in tracking heuristics could lead to wildly inaccurate conclusions even by well-intentioned operators and analysts.

I can't speak for the radar data, as I've never seen even leaked radar page footage from these events, but for those of you out there who think that what you see on the scope is a perfect analog of the real world, boy do I have some bad news for you...

It's also interesting to me that every single one of these videos I'm aware of has come from what's generally regarded as the least capable and most error-prone targeting pod currently in US service.

The main reason is stiffness—off the top of my head, it’s roughly a quarter as stiff as typical steel, so it needs significant engineering and often much more reinforcement to keep the concrete within allowable deformation limits. Basalt and carbon fiber are more promising replacements, but are significantly more expensive.

I mean, in the 1980s turbo era F1 engines were putting out way more than that--try around 1000 hp/l!

That was done with absurd levels of boost, fuel that bore little to no chemical resemblance to gasoline, and engines with a life expectancy (in qualifying trim) measured in single-digit laps.

The advances in modern engines' efficiency and reliability are staggering.

https://en.wikipedia.org/wiki/BMW_M12

With a fission bomb.

Don’t have a good explanation for your second question, although I think the short answer is “not with the way the Livermore experiment was set up.”

The short answer is no.

Check out frontal head restraint systems. In combination with a good harness they eliminate the C-spine concern, at the cost of reducing your field of regard a bit. If they can figure out the mobility piece, I’d happily drive with one on the street over air bags.

Check out 14 CFR 91.119 [1]. Over sparsely populated areas, there is no specific minimum altitude requirement—only that you need enough altitude to safely land following engine failure.

[1] https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F...

I'm not an etymologist, but I don't think the word "analog" originally referred to electrical circuits when it came into use.

I think the figurative use case we've given it makes way more sense than a lot of other words we've given new connotations to recently.

If we're talking military logistics, that may well still win out on efficiency over current methods. Even if it doesn't, it still has enough potential advantages to be game-changing.

You'd be surprised at how often they do--especially at how often the planes involved land safely despite the damage.

Often enough that it isn't good practice to assume one outcome or the other.

My best guess based on the video is that the P-63 pilot had been high and out of position in formation, and tried to get back in position using both geometry and speed. He may have recognized that he had too much closure and wasn't in position to safely underrun the B-17, and tried to bank and pull to get safe lateral separation, inadvertently putting himself into a blind lead turn where he wouldn't be able to see the B-17 through his wing or fuselage. The blind lead turn is an incredibly dangerous maneuver in formation flight--typically prohibited in military air combat training--for obvious reasons.

Ah, gotcha. Yeah, there’s zero chance that you can make a pressurized pancake using rib-and-stringer architecture, probably even out of unobtanium. The best candidate I can think of is making it like a submarine, although that would definitely mess with the open concept floor plan and probably impose a huge weight penalty (although it might be helpful from a fatigue life standpoint). The only other remotely viable solution I can think of is drop stitching, but that has some fairly obvious drawbacks that would probably make it impracticable.

How is that a meaningful distinction from either a design or manufacturing standpoint?

I mean, the rise of low-cost carriers has shown pretty clearly that passengers are willing to put up with a lot for cheaper tickets…

I mean, aerodynamic drag scales linearly with both Cd and A. It isn’t too far-fetched to think that you might be able to trade them off in a blended wing design and come out ahead by reducing interference drag and wetted surface area.

The pressure vessel problem is much more concerning to me—I can’t think of a way to solve it that wouldn’t massively increase weight and/or reduce usable space.

To be fair, the B2/737 comparison isn’t particularly fair—they were optimized for wildly different things, and only one design was significantly constrained by acquisition and operational costs.

Take a look at 14 CFR Part 23. The standards are performance-based. I don’t think I’ve ever seen any kind of proposed aircraft design that doesn’t fall into existing categorization.

The differences in ribs across the span of a wing are much less of an issue than compound curvature in the wing skins—this is where composite manufacturing really shines, because you can mold them into arbitrary shapes.

To be fair, even if Boeing's legal team cuts the CYA maintenance clause out of the purchase agreement, absolutely nothing will change in terms of actual maintenance on the aircraft they sell. The FAA requires all certified aircraft flying in US airspace to be maintained in accordance with the manufacturer's approved instructions as a condition of airworthiness.

Doesn't seem like a great analogy for consumer electronics sales.

Classic “screamer” failure—the tag line is that you have the rest of your life to figure it out. “The Man Who Rode The Thunder” is another classic parachute story worth reading.

Also the Foreign Dredge Act [1]…

[1]https://en.m.wikipedia.org/wiki/Foreign_Dredge_Act_of_1906

Do you have a source for the Gulfstream type rating cost? Most type ratings cost around $10-15k, and the most expensive I’ve seen is around $35k. Very few pilots pay out of pocket for type ratings, but the vast majority who do only need to take a low 5-figure hit. An aspiring airline pilot could self-fund all the formal training they ever need for under $100k.

There are a number of VTOL aircraft that have used multiple engines. The Yak-38 used two lift engines and one lift-cruise engine, the VJ101 used four lift-cruise engines and two lift engines, and the Do 31 used two lift-cruise engines and eight(!) lift engines. Out of these, only the Yak-38 was remotely successful, and not nearly as much as the single-engined Hawker Siddeley Harrier (and its derivatives).

There are plenty of ways to stabilize an aircraft without relying on pure engine thrust, and turbofan aircraft have some advantages here.

The distributed electric propulsion systems do have awesome redundancy, but they have significant losses in efficiency compared to fewer, larger props, which really isn't what you want in an aircraft with severe energy density limitations. I'm curious to see what the production Lillium's payload, range, and power margin end up being.

I would argue that various forms of cycles (going well beyond the UCI definition of a bicycle, but still using common components powered primarily by a human) are much more compatible with disabilities than cars are. I've seen both double-arm and double-leg amputees cycling, among others.

Ooooohhh, the air-cooled vs. water-cooled argument is a great one. The mechanical simplicity of air-cooled engines is a very strong point in their favor, but it's arguably the only one. Water-cooled engines can be run leaner (i.e. more efficiently) because they don't need to run rich to keep cool, don't have uneven cooling issues, aren't susceptible to thermal shock when going to idle during a cruise descent, have better power-to-weight ratios, and don't have as big of a problem dealing with the dilemma of having the slowest/warmest airflow when the most engine power is needed (during takeoff and go-around conditions)--all for the relatively modest risk of a pump, radiator, or hose failure. In an alternate reality where we had seen the same amount of R&D go into general aviation piston engines as automotive ones, I wouldn't be surprised if nearly all light aircraft used hybrid-electric liquid-cooled engines with reduction gearboxes.

Fair point—I never got good at “dating” as a standalone skill. I still think that’s the benefit of activity dates over bar/dinner-and-a-movie/whatever dates, though. Doing a thing that you’re both already reasonably confident at helps counteract the anxiety and pressure from being on a date, and if you both have a good time doing the activity it makes follow-on conversions easier and less stressful since you have a common foundation to build and/or fall back on.