No argument here. A good thing to touch on is what they need in their inventory by 2030 for the air force.
Low/medium altitude, slow moving UCAV supporting army (kind of like Q-5 replacement)
I am not convinced that any UCAV should be "low altitude".
Operating at low altitude is suicide and puts you at risk of even MANPADS.
Medium altitude UAVs may have a role in more permissive environments (those would be your generic MQ-9, WL-2 type UAVs or smaller MQ-1, WL-1, CH-3/4 style UAVs), but against a high intensity foe, it is suicide.
There should be no replacement to Q-5 just like how there should be no replacement to A-10. Operating at low altitude to conduct interdiction or CAS is cold war era thinking.
Interdiction and CAS today is all about having the EO sensors and PGMs on your aircraft that is operating at medium or high altitude, and the same principles exist for manned and unmanned aircraft alike.
medium/high altitude, medium/high subsonic UCAV capable of attacking air defense, naval ships and other high intensity environment
medium/high altitude, supersonic UCAV capable of A2A combat as well as A2G missions.
I think these are the two most important UCAV roles of the future.
Stealthy strike UCAV, and stealthy A2A UCAV.
Both of those types of UCAVs have their own desirable traits in terms of range, endurance, sensor and weapons loadouts, and ability to be attritible.
That said, I have a feeling that the stealthy A2A UCAV may seek to be developed to be more attritible than a stealthy strike UCAV.
And in case other people raises it -- no, A2A UCAVs will not high performance hyper agile fighters that are pulling crazy amounts of Gs and being slaved to manned fighters. This isn't anime, and the point of developing A2A UCAVs isn't to fly in a more vigorous manner than what stresses the human body can handle.
Instead, A2A UCAVs should be seen as stealthy, distributed, and attritible sensor and weapons platforms, where their sheer quantity helps to massively strengthen your system of systems aerial battlespace, to provide your side with superior first look, first shoot capability at BVR.
In such matchups, stealth, ECM/EW, and distributed A2A UCAVs will be widespread, and the side which wins will be the one that possesses a superior and more robust networked air fleet in terms of both quantity and quality. That is how VLO fighter aircraft will seek to counter each other -- not by blindly encountering each other and then engaging in WVR combat, but seeking to further extend and distribute their sensor and weapons capability by saturating the battlespace with forward deployed MUMT A2A UCAVs to enable themselves to detect and engage the enemy, before the enemy can detect and engage them.
I agree with all of this. You can keep increasing the thrust (larger engine or more engine) to carry more fuel and payload, but what is the right size? You don't want it to be too large, because then it will be too expensive and not attritable anymore.
If you intend to operate it with just fighter jets, then it would only need maybe 1500 km combat radius and maybe 8 hours endurance at full payload. With 1 non-AB WS-10, could you carry 3t of internal payload with that? Probably
If you intend to operate it with H-20s as well as J-20s, then you'd need 4000 km combat radius. That would require a larger UCAV.
I think the "right size" or indeed, the "right aircraft" fundamentally is dependent on what mature technology and production you have available (a proxy of national wealth), in addition to the role of the aircraft.
A non-AB WS-15 would be more powerful than a non-AB WS-10 for example, but WS-15 is probably going to be in high demand for J-20 production (and possibly 6th gen fighter development) going into the late 2020s, so the likelihood of sparing WS-15s for mass produced UCAVs is unlikely.
But WS-10 and WS-13 are relatively well known quantities, and WS-10 in particular has been in production for a long time now.
For some nations, in the near future they might have the industry and the money to build and mass produce UCAVs with sensor and weapons suites that are equal to that of a manned 5th generation fighter -- but for other poorer and less capable nations perhaps they are unable to even build a manned 4th generation fighter.