Dude F-35 is 120 million, without weapon systems. There's no way F-15 is that much, the Silent eagle maybe.
Besides, S-300 is getting phased out, with the new stealth fighters, the strategy is to destroy all anti air batteries and then comes the 4th gen fighters and bombers.
So anti air may not be the investment you think it is.
ViXueng says SU-35, not F-35. As long as America still holds embargo on Vietnam, it is useless to talk on buying of US weapons.
No, modern anti aircraft systems can track all targets, including stealth fighters. Have you ever heard of passive radar system?
A conventional radar station sends out a powerful search beam, which is reflected by ships or aircrafts. From the echo, the computer can calculate the position, course and speed of the target.
A passive radar does not require an own search beam. It analyses the wave salad coming from the atmosphere. Any object such as aircraft or ship moves through the wave soup like a fish through the water - and raises inevitable return of measurable echoes. A stealth jet cannot hide because it is hit by radio waves at all sides. High performance computers with complex math algorithmen analyse the wave soup and identify the objetcs.
Plus a passive radar works faster. Unlike a classical radar whose search beam takes about four seconds for a full 360-degree turn, the passive radar image is updated twice per second.
Here is a passive radar system from the company EADS Cassidian: It fits into a conventional small truck. It uses three frequency bands: analogue UKW, digital radio DAB and digital telvision DVB-T. The company promises the radar can locate small flying objects, stealth fighter aircrafts, up to 500 targets up to a distance of 200 km, with an accuracy of 10m.
Vietnam needs such a toy combined with a high performance anti aircraft system. Stealth jets do not mean invisible.
Passivradar: Das Ende der Unsichtbarkeit - SPIEGEL ONLINE - Wissenschaft