Hopfgeist

joined 1 year ago
MODERATOR OF
[–] Hopfgeist@feddit.de 0 points 1 year ago* (last edited 1 year ago)

I don't think there's anything intrinsically wrong, but far as I can see you are using only a single disk for the zfs pool, which will give you integrity checks (know when something is corrupted), but no way to fix it.

Since this is, by today's standards, a tiny disk at 100G, I assume this is just a test setup? I'm not sure zfs is particularly well suited for virtual machines, I think it is better to have the host handle the physical data integrity by having the disk image on a zfs filesystem, or giving the VM a zfs volume (block device) directly.

[–] Hopfgeist@feddit.de 0 points 1 year ago

Good news, if true. I have a soft spot for any delta wing fighter, especially true deltas without empennage, so that includes Delta Dagger, Delta Dart and all Mirages except the F1.

[–] Hopfgeist@feddit.de 0 points 1 year ago

[...] they are being acquired in cooperation with other countries.

So presumably from some ex-Warsaw-Pact-now-NATO countries, of which there are quite a few.

[–] Hopfgeist@feddit.de 0 points 1 year ago

That's how I read it, too. Putin won't allow the military to withdraw, even if everyone on the ground knows that that would be the only sensible option. For everyone. (Except Putin, maybe, although even he could give it a positive spin if he wanted to.)

[–] Hopfgeist@feddit.de 0 points 1 year ago

I have now, but that doesn't really change my mind. You have a point and it becomes a matter of semantics. I don't think it's actual malice in that he consciously wants to cause harm (on balance), but that he is so thoroughly misguided because of his own sense of infallibility, that he truly thinks he is a force for good in the world. Is that stupidity? It becomes a matter of definition. The video is too short and selective to really make any call based on it. "There are no 'ordinary' Russians on Twitter"? How can he tell? Maybe he has explained that in previous videos.

[–] Hopfgeist@feddit.de 0 points 1 year ago (2 children)

I would still argue that Hanlon's razor applies: "Never attribute to malice that which can adequately be explained by stupidity."

[–] Hopfgeist@feddit.de 0 points 1 year ago

Yes, this is designed to work with absolutely minimal infrastructure and very few trained personnel, very much unlike the F-16, which requires sophisticated equipment, not to mention hydrazine, which is truly nasty stuff and cannot be handled in the field.

Gripen is what Ukraine desperately needs. You can literally refuel and re-arm it at the roadside in a forest with three trucks and 6 people, 5 of which can be conscripts.

[–] Hopfgeist@feddit.de 0 points 1 year ago

One urgent thingis that the EU follow the UK in abandoning the ill-conceived "client-side scanning", aka Chat-Control.

[–] Hopfgeist@feddit.de 0 points 1 year ago

This is an ECM/reconnaissance drone, not a cruise missile. So no "target" in the normal sense (although I wouldn't be surprised if it was going to be used a cruise missile, too). And reduction of induced drag (raked wingtips or winglets for transonic; straight high aspect-ratio wings with elliptic lift distribution for subsonic) works the same at both scales. At a cruise speed of 600 km/h this is fast, but almost certainly fully subsonic, so sweep makes little sense aerodynamically, in either direction. If they were bothered about fuel efficiency, it would have long, straight, high-aspect-ratio wings, like the Global Hawk, or the Reaper, or the Predator, and a turbofan or turboprop engine.

I'm sure they're no idiots and have very good reasons for the design decision. I just doubt that the reason is aerodynamic efficiency.

The beaver cruise missile is completely different, it is a propeller-driven canard with straight wings. But that may actually be the reason: they re-used the fuselage design, and with the same wing attachment point, forward sweep was required to maintain a reasonable centre of lift in a conventional configuration. Again: a compromise for a short time to deployment. Not aerodynamic refinement.

[–] Hopfgeist@feddit.de 0 points 1 year ago

That's the point. This is not a very refined design, it is a quick-and-dirty, "good enough" approach to get it out of the door as quickly as possible while still fulfilling the requirements. Which is why I found it surprising that forward sweep was deemed the best option, despite its aerodynamic and structural challenges (which usually outweigh any benefits). And as I said, fuel efficiency was not foremost on the designers' minds. Case in point: small turbojets are notoriously inefficient (only pulsejets and rockets are worse), and many small details could be improved cheaply. But having a large unobstructed payload bay is a very good reason for forward-swept wings on such a small design and can greatly simplify operation. I will not recommend any computational fluid dynamics package, because it takes many years of study and experience to apply it to real-world problems meaningfully. And if the design team includes aerodynamicists, they will know what software to use anyway, and don't need my recommendation. Surprisingly, if you have good data on the airfoil cross-section performance, X-Plane is not the worst tool to get a good idea of performance and stability. It was used for Solar Impulse in that way (also for pilot training).

[–] Hopfgeist@feddit.de 0 points 1 year ago (4 children)

If it were beneficial in total, most transonic planes would have it. The only aerodynamic advantage over backward swept wings is higher manoeuvrability, which isn't a priority here. This isn't a dogfighter. My money is still on better payload distribution.

more effective control of the ailerons

Not sure what that means. I don't think agility is a priority with a jet-powered drone. Or benign stall characteristics.

reduction in vortices formed by the wingtip which would increase drag and decrease efficiency

That is negligible. We know how to reduce wingtip vortices, and reverse sweep is not the answer. Raked wingtips as used on the 787 and the larger-wing versions of the 777 and the 777X are optimal for transonic flight. Blended winglets are a close second, as used on the A350 and A330neo. Again, not forward sweep.

This thing also does not look very refined aerodynamically, and there are many more things that could be done to reduce drag that are much cheaper. Wing-body fairings come to mind to reduce interference drag, or winglets if you really want to go there. This has all the looks of "Eh. Good enough. Send it!", which makes sense given the urgency.

[–] Hopfgeist@feddit.de 0 points 1 year ago (6 children)

I wonder what the design decision was for the forward-swept wings. These typically decrease lateral stability and increase structural weight, because they require substantially higher stiffness for flutter-resistance compared to straight or rear-swept wings. Maybe so the main wing spar can be further aft to have a larger contiguous payload bay. The HansaJet had forward-swept wings for a similar reason (no main spar in the cabin).

view more: ‹ prev next ›