Whoa, hold on there and put away the can-opener please

AC land after making an "approach move", which is still a *move*. However it is not a
"Ground move". So to that extent they still "barge" like any other WE.
There was a whole lot of discussion way back in the past about what did and did not trigger OW. Ultimately it was decided that a "Ground move" and "disembarking" triggered OW, but not air-transports making an "Approach move" or "Planetfalling".
Here is Neal's comments on this point:-
nealhunt wrote:
Rug wrote:
And Overwatch? When the aircraft lands and when troops dismount, or just when troops dismount?
Only on the dismount.
For a history of this ruling, picture a time when Deathstrike Missile Launchers had the "no line of sight" note instead of the Indirect Fire special ability. Now picture a DS on Overwatch as an enemy aircraft loaded for assault comes onto the board. If the DS can fire before troops dismount, it's basically a 2+ autokill, ultimate air defense (and for ~800 points of SMs, you better believe people were firing both missiles to avoid the risk of a 1).
The result was Jervis' FAQ stating that for purposes of OW, only normal ground moves apply as a trigger, because he felt that was a clarification/correction he could make without directly contradicting the RAW.