> As soon as someone learns to detect F35 radar signal, more than half if it's stealth advantage melts away.

Much of the stealth advantage of any aircraft evaporates as soon as it turns on its radar. It's not a matter of "learning to detect" anything. An aircraft that wants to be stealthy runs with radar off and relies on passive sensors. A system like this, if it could be made to work at the scale of a fighter radar, would change that.

> F35 sales pitches are probably warming up right now, so news like this are expected.

Scaling this system up to the range and power required for a fighter radar is going to be a lot of work.

> The only surprise for me is that this comes from the army and not the air force or navy. They probably need to worry about enemy droids. And if they worry about those droids using radar, they need to worry about enemy anti-radiation missiles.

I will hazard a guess that this effort grew out of the artist formerly known as Future Combat Systems. Part of the effort was the Multi-Function Radar Frequency System (MFRFS, pronounced "merrfs") which was a vehicle-mounted scan-and-warn radar that would have been part of a larger active protection system. The idea was to identify incoming ordinance, particularly RPGs, and 1) identify the shooter's location; 2) identify the specific target vehicle and warn the crew; 3) trigger an active protection system, if equipped.

All of this predates drones, and the Army has been interested in small-scale radar for decades. The concern on detectability is to keep the enemy from identifying and tracking ground forces using systems like MFRFS by using the emissions from the sensors.

> This is probably part of larger picture of U.S. armed forces to avoid using Infra Red Search and Track (IRST). Because that makes stealth planes look bit silly, when you go past ~0,07m^2 radar cross section. At that point you would get parity with detection ranges of common radars and modern IRST sensors, which would be something like 80km for fighter jet sized object. But this would mean no operations in enemy airspace, as flight ceilings are typically around 20km. F35 has RCS 0,01 and F22 RCS 0,001 which is just great for operating in enemy airspace, if the enemy can't detect their radars and lacks IRST.

I have no idea where you are getting RCS numbers from, since those are classified.

As for IRST, I have no idea from where you got the idea that the US is ignoring it. The US Navy and Air Force have been mounting IRST sensors on their fighters since Vietnam. The F-22A and F-35 carry the very sensors you say the USAF is ignoring. Also, an IRST sensor can detect a fighter (ass-on) at 80km; it cannot identify or track that aircraft like a radar can. It needs to be much closer to do that.

> Currently it seems the best USAF can do about IRST is to pretend it doesn't matter. So if there is any coordination between the branches, the army has to get their own stealth radar against enemy drones. After two decades and gazillion dollars, we probably see subsonic F40-cool-skin, with reflecting mirror finish aluminum body, that eliminates this problem. And power projection and proceed uninhibited.

No, you won't. First off, the primary source of heat in an aircraft is the aircraft's own power plant, not solar heating. Second, a mirror finish would be a beautiful target for radar. It would be a blinding "KILL ME!" sign to even the most primitive systems. For that matter, so would a subsonic aircraft. Third, like I said, not modern air force is ignoring IRST.

> Right now we don't hear about this aluminum shit, because U.S. is still funding some weaponized lasers. Airborne lasers smelled like "overspending" before, but it's really going to smell like bluff when reflecting surfaces increase power requirements some 400%. They already suffer from bad power/weight ratios. But once naval laser "close-in weapon system" has been fielded (because any chance is a good one when you're desperate) we can go back to airplane design.

The airborne laser projects are intended to target ground vehicles and missiles, not aircraft. Naval CIWS is also intended primarily for targeting missiles. Current gun-based systems only have a range of ~2km, and no fighter pilot has been ballsy enough to come that close to an enemy ship in combat since the Argies bombed British landing ships at mast height in the Falklands.

> Sorry, this is bit long. I've had this autistic streak about this subject for past two weeks.

Yeah, so am I. I worked in it for almost a decade, though.