Sure, but this doesn't make the gunships less useful, it just means that they need support, just like any situation where you used CAS in more conventional wars such as WW2 or the Korean war. It doesn't diminish the utility of a gunship.
I am not denying that a gunship can't be useful, it just won't be useful against Cannalans in their current state. Ironically enough, it'd have much better go at it after we make the SAM. Also, gunship require way more support than regular CAS, considering that they're spending a lot of time over the enemy, rather than dropping the payload and retreating to relative safety. Gunships kill people, but they aren't a design that I can see being effective in our case, and honestly, I can't see it being effective most of the time during an Arms Race, because they're very easily countered.
Helicopters also orbit in the exact same way because it's safer than flying directly over the target,
Yeah, no. Helicopters sure show their side, or at least should, but helicopters also operate on lower altitudes and (should be, Cannalans are just... special) are more agile. Not to mention that if we're talking about helicopter gunships the entire doctrine pretty much calls for fast and quick attacks and then retreating behind the safety of cover, since you can actually hide a helicopter beind a hill, not to mention the same thing as with CAS kind of applies - attack helicopters have most of their weaponry mounted at the front, and so they face the enemy when they're attacking and then break off. Fixed-wing gunships just float in the air over the target on very predictable trajectory, and while they could change that trajectory, it is at cost of losing the ability to shoot pretty much.
it's really hard to hit an aircraft that is constantly changing it's direction by moving in a circle,
...what? If it's moving in a circle it's not constantly changing direction, it's moving essentially in a straight line, except it doesn't really change it's distance from the middle of said circle, and... I don't even know how to begin explaining that because that would require you to understand basic concepts as leading the target, "walking" into fire, and just fucking basic ballistic pretty much.
and to anything that's in its killzone it's moving left to right
Which it can't do because it has guns only on one side, unless ours doesn't, but then it'd be very fucking hard to fit TWO tank cannons, and whatever additional weaponry. There's probably just not enough space for that, especially considering that tank cannon is gonna need some serious fucking dampening.
which is a very favorable condition (aircraft get shot down when they're hovering or they're flying straight towards something that's firing at them which is why attacking ships on water in WW2 was so dangerous).
Attacking ships was dangerous as fuck but LITERALLY FLYING TOWARDS THE ENEMY ANTI-AIRCRAFT is one of safest ways to approach one, since it's probably the approach that gives you the most possibilities to dodge. There's a reason why they did it this way. I'm not even going to comment on hovering.
And yet we have examples of gunships doing exactly that and surviving, usually because their mission was considered so important and their contribution so valuable that casualties were acceptable, and because gunship crews are expecting to be shot at while they're performing a pylon turn and train to exit that maneuver in the safest way possible when things do get too dangerous. The fact that an aircraft has been shot down before by AAA isn't proof that it's not a useful or survivable platform, not only do you have to show that an orbiting aircraft is more likely to be shot down than a strafing aircraft, you also need to show that this supposed loss in survivability outweighs it's effectiveness as CAS.
Like a dozen AC-130s arrived in Vietnam. Six were lost. Three to 37mm cannons, one to 57mm cannon, one to a Strela and one to a SAM missile. Of course they were replaced with the war, but I again remind you that Vietnamese anti-air capabilities were not enough for a conventional war. Fixed wing gunships are anti-insurgency weapon, and this isin't a fucking insurgency, it's a war.
Based on one incident which you haven't formally cited you argue that unguided 37mm cannons frequently shot down fixed wing gunships,
Google is your friend.based on one incident I show evidence that a gunship can survive being targeted by radar-guided AAA, yet in your example the outcome was inevitable and in my example the gunship was lucky. Why?
I honestly don't even know how to argue anymore, if you reject evidence and common sense I am not going to win it, so whatever. Can't use my own tricks on me. :I
E: More about friendly fire:
All our aircraft have radios already, if friendly fire does become an issue then you just install IFF transponders. It's just a radio code that the radio is constantly spitting out and SAM sites will interrogate the target before engaging. Easy solution.
This is what I considered, the problem is I am not sure if we can just make IFF transponders in the same design, and Cannalans might just fucking copy them and put them on their own planes. Might be worth adding them.
UFAF-AGS-44 'Endless Vigil' [with research credit]: (1) Madman
UF-GAM-44 "Noose" [with research credit]: (5) Kot, Cnidaros, NAV, ConscriptFive, Kashyyk, eS