Air Combat (Long War)
UFOs are tougher, faster, and much more deadly in the Long War. Along with that, your crafts and armaments are significantly less potent, at least at first. You'll be needing to cycle your craft regularly (like your soldiers), as kills now grant a sort of XP to accuracy, as if your pilots learn UFO flight patterns and movements, and learn to fire with increasing accuracy with their experience. Interceptor experience provides +3% to hit per kill (up to + 30%) and +1% damage per kill (with no top limit).
The LW mod brings back a mechanic from previous generations of XCOM: UFOs can now have full DOA crashes (with minimal Alloy recovery, and no corpses or other artifacts), so in some cases you may want to pull your punches. To compensate, the Council will give cash rewards for UFOs obliterated in flight.
For starters, the Avalanche Missiles, on your fresh pilots, now have an abysmal 40% accuracy. While it is possible to still down the first Scout with one Interceptor, this is incredibly unlikely, and most likely it will take two, or even three interceptions to bring down these upgraded craft.
UFOs can fly at three altitudes. The altitude is a clue of what mission the UFO is going on. In Beta 9, the altitudes are "Very High," "High" and "Low." In Beta 10, this will changes to "High," "Low," and "NOE," the last meaning "Nap of the Earth." UFOs flying at the lowest altitude are most likely to land or generate an abduction or terror mission. UFOs at the highest altitude are most likely to be hunting satellites.
You may now also set a combat stance for your interceptors as they launch on a mission. Aggressive gives +15% to hit for both you and the UFO; balanced plays out like normal, and Defensive gives -15% to hit for both you and the UFO. You may not use the dodge consumable when aggressive and you may not use the auto-hit consumable when defensive.
It seems that a low-flying UFO's inital flight vector is randomly generated when it's event marker date arrives (ie: the "Intel reports heavy UFO activity over <Country>" notices), and that in actuality, satellite coverage just 'unlocks' the capacity to see it. What you may find is that if these UFOs cross over a satellite covered country, you may have a narrow window in which to intercept them, even if their desitination country is uncovered. So, on the exception to the previous paragraph: Abductors, for example, may automatically trigger an Abduction Mission if they land in an uncovered country, since your satellite won't be there to catch it landing.