At the time the only thing which can intercept F111 advark in most of scenario (including high altitude bombing ) is F-16 ocu, the rest of Indonesian fleet at the time is consisted of F5 Tiger, Hawk MK 209/109 (in which many still at delivery process) and A4 skyhawk in which all of them is only being Armed with short range AA missiles like sidewinder. Meanwhile our Navy still consisted of archaic gunboat /torpedo/ASW warships just like the Tribal class, Parchim class, Claude jones class, and the most advanced ones is the Van Speijk class and Fatahillah class in which neither of them being Armed with decent Air defense system.
Fast forward around twenty five years to the future, Indonesian Air Force only adding some number of Su27/30 fighter, F-16 C/D, T/A 50 and now only recently adding a decent number of Rafale fighter.
While in the region Australia Air Force already going Gung ho with four squadron of F35 fighter, a squadron of Growler and a number of Super Hornet, that's too with the intention to bolster the number with loyal wingman program. Singapore already fielding a decent number of 4++ generation fighter aircraft (64 F-16 block 52 along with 42 F15 SK). The Malaysia with at least 8 Legacy Hornet and 18 Su 30 MKM. Indonesian Air Force at least needed to have some parity of forces against all of her closest neighbor (that's including Australia, Malaysia, Philippines and Singapore) at the same time in which needed to bolster Indonesian air power deterrence, increasing leverage and bargaining chip at any would be potential conflict over maritime dispute and also to save guard Indonesian territorial rights and claims.
