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Ukraine uses (among other things) fixed-wing drones with similar characteristics to civilian aircraft. Some of them are *actual* civilian aircraft, retrofitted into unmanned suicide drones,

https://www.flightglobal.com/military-uavs/ukraine-appears-t... ("Ukraine appears to deploy modified A-22 ultralights as suicide UAVs")

Unmanned kamikazes?

They are just DIY cruise missiles really.

None of them remotely resemble an E190 though, which is about 50x the size of a cruise missile, communicates effectively with air traffic control and broadcasts ADS-B signals telling you what it is (at least when you're not jamming it...)

Radar doesn't exactly tell you the size of of a contact. Sure, you can measure the power of the return signal, correct for distance and get something that loosely correlates with size. But it correlates much more strongly with other things.

You're also making the assumption here that it was a modern Russian system. This wasn't exactly close to the current fighting, its entirely possible this radar was manufactured in the Soviet Union. I don't think those receive a lot (or any) civilian broadcasts.

> You're also making the assumption here that it was a modern Russian system

People do like to provide their very important opinion completely oblivious what Grozny is farther away from eg Crimea than Kiev.

Since Russia reduced Grozny to rubble relatively recently, it's probably not that old.

Most A2A systems has wheels (or floats) and can thus easily be relocated. While it probably had good stuff once, I think all the high end equipment once located here has moved closer to Ukraine by now. What's left is probably the worst (human or technological) that's left.

> Ukraine uses (among other things) fixed-wing drones with similar characteristics to civilian aircraft.

Including taking off from commercial airports on publicly available schedules, on predetermined airways/corridors, and broadcasting 1080 MHZ ADS-B data?

> Some of them are actual civilian aircraft, retrofitted into unmanned suicide drones

literally small prop planes with guidance systems and instead of ~4 passengers it's lots of explosives. commonly used against Russian oil depots, etc.

small radar signature, and a lot of ambiguity with civilian aircraft.

Confusion with civilian prop aircraft, not commercial jet airliners flying at vastly higher altitude and speeds.

An E190 on approach (remember, this airplane was trying to land at Grozny) has an approach speed between 125-145 knots (depending on load). A Cessna 172 for example has a cruise speed of ~120 knots and can cruise up to 10k feet. A typical instrument landing glide path is 3 degrees - that intercepts 10k feet at ~60km out.

The likelihood of confusing a regional jet with a small prop plane (purely based on speed/heading/altitude) is way higher during landing.

While it crashed near an airport it doesn’t seem like the aircraft was targeted at low altitude and low speeds.

This aircraft was trying to land so it likely had much lower altitude and speed than usual.

It doesn’t appear that the aircraft was attacked on final approach. Instead flying much higher and faster than prop drones.

> With zero knowledge of how well-equipped the Russian military is, could they really be so far behind that they're unable to determine the difference between an commercial airlines and a high-speed missile

If they exclude radar signature of commercial airliners, and let them fly, it will just make weapon makers start designing high-speed missiles with the radar signature of an airliner lol.

There is a reason why a lot of military and sci-fi movies have the phrase “aircraft with radar signature of a bird” , anything that the military excludes or allows to pass off, just becomes the cloning target of missile makers under the tag of “camouflage”.

> ... it will just make weapon makers start designing high-speed missiles with the radar signature of an airliner lol.

Well, the problem with that is that airliners are (relatively speaking) slow as fuck. A "high-speed missile" with the radar cross section of an airliner would be mind-meltingly obvious as a threat even to automated defense robots.

Iran mistook PS752 for a cruise missile [0]. It's not an impossible mistake; a cruise missile is (often) a subsonic, jet-powered object.

[0] https://en.wikipedia.org/wiki/Ukraine_International_Airlines...

Point of order: A cruise missile isn't a high-speed missile. It's (almost?) always a big, slow, lumbering bastard, as far as missiles go.

There are cruise missiles powered by ramjets that go significantly supersonic, but for the most part ballistic missiles are easier to use, longer range, and harder to intercept. The prospect of anti-air systems effective enough to pose ballistic missiles trouble in a "near-peer" non-nuclear conflict is recent. Both maneuvering-capable ramjet/scramjet cruise missiles and (the significantly easier) maneuverable hypersonic re-entry vehicles that launch ballistically, are the subject of recently fielded early models, active development & active testing because of that prospect.

Hence the term "cruise", which in every other context means not traveling especially fast.

Airliners aren't slow by cruise missiles standards: supersonic cruise missiles are few and far between, and most cruise missiles in fact fly roughly at the speed of an airliner (between 800 and 1000km/h).

You're the second person to talk about cruise missiles in this subthread.

The comment I replied to (and quoted in my reply) talked specifically about "high-speed missiles". Nearly all cruise missiles are most emphatically NOT that sort of missile.

Stealth airplanes might have the radar cross section of a bird but they don't have the same flight characteristics (altitude, speed.) If you can manage to see it, you won't confuse it for a bird.

put another way, your average seagull ain't cruising at 10000 feet @ 600 mph

A flock of migratory birds could very easily be cruising at that height, and if in a fast moving jetstream or similar could be moving at hundreds of miles an hour when referenced to a ground based source.

That came as news to me. Some fly at 11200m/37,000 feet.

https://en.m.wikipedia.org/wiki/List_of_birds_by_flight_heig...

If you've ever dropped a French fry at the beach, you know that's not true.

> it will just make weapon makers start designing high-speed missiles with the radar signature of an airliner lol.

The weapons industry isn't that enthusiastic about blatantly violating the Geneva Conventions. There would be massive diplomatic costs to making, selling, buying or firing missiles with fake civilian transponders.

When I look at current conflicts, I’m not sure that the Geneva convention features anywhere in anyone’s thought processes.

You are describing a war crime.

> With zero knowledge of how well-equipped the Russian military is, could they really be so far behind that they're unable to determine the difference between an commercial airlines and a high-speed missile?

In a quick decision, in a high-stress scenario during an actual attack, possibly. Even if they have the capacity to make that decision correctly otherwise, every system—including the human element—is fallible, and procedures in those circumstances are likely to err on the side of safety-from-attack, rather than safety-for-potential-attacker.

(OTOH, the rerouting of the plane afterward was clearly intentional murder with the hope it would help cover up the shooting incident, whether or not the shooting itself was an accident.)

Wait a minute. I thought they hit some angry birds?

All of these decisions are made by soldiers. Russian air defense troops are no doubt overworked, poorly treated, under intense pressure and probably motivated by avoiding going to the front.

Chances are, an operator or officer made a bad call. They are cogs in a killing machine.

I would have thought the aircraft’s transponder would have been the first clue. I can identify nearly every aircraft over my house right now using a $30 USB dongle, including callsign, airline, flight number, altitude, speed, and bearing.

> With zero knowledge of how well-equipped the Russian military is, could they really be so far behind that they're unable to determine the difference between an commercial airlines and a high-speed missile?

It depends a lot on the context (weather, altitude) and equipment (Russia has a lot of equipment, some of it new, some of it old, some of it ancient).

Without minimizing the personal contribution to this disaster of every serviceman, IMHO the blame, first and foremost, rests firmly with whoever the bloody hell decided to keep the airspace open nearly three years into a war. Civilian airspace is open above Chechnya and Dagestan while the VKS is lobing missiles from/from above the Caspian Sea, and planes are landing at Sochi while Novorossiysk gets hit by drones. This is nuts even by post-Soviet standards. There's a very good reason why Ukraine closed their airspace almost right away and continue to keep it closed.

To pre-emptively address the "but that would be too costly" angle: well, maybe that should've been factored in before greenlighting the invasion. Boo-hoo. Does keeping it open look cheap now?