Lots of ppl think u can enter the base without all 100 packages but thats not true, u must have all 100 packages before going into Baxter air base to get the apache,there are 2 ways of going into the base without getting shot.

#1 U get the police uniform at the police station that u can enter(near construction site) and get a helicopter, from there u go to the end of the military base and take the apache.

#2 (if u dont want to get a helicopter),get the uniform,then drive all th way to the base into the gate(breaking it) then turn left to some stairs that lead to the roof of a building, then u go to the other side of the building to a small walkway on the side of the main building,go through the walkway and down some more stairs, in the area that u r in there are fences and a tower,go up the tower then jump of the side of the tower to go in the "training area", go to the end of the training area and u should find an opening in the fence, go through it and u should be in the end of the base, from there u walk left a little and u should find the apache(hunter)
*****BUT REMEMBER,u have to have all 100 packages and the police uniform,if u cant find the police uniform u can unlock by finishing the mission Cop Land