Although only with old anti-aircraft missiles, with flexible tactics, the Houthi militia successfully shot down the F-15 fighter of the Saudi Air Force.

On December 11, Yemen’s Houthi rebels released a video, confirming that they had damaged a Saudi Air Force F-15 fighter jet over Juba, Yemen. In the video, the air defence missile of the Houthi forces hit the F-15 the plane was not destroyed immediately but continued to fly, but because the missile exploded very close, certainly, the F-15 was seriously damaged by the missile debris and It’s not cleared whether the above F-15 returned to the airbase.
the Houthis announced the type of missile used in shooting down the F-15, which was the Fateh-1 missile that was made public a few years ago. This type of missile is actually a 3M9M series air defense missile, of the 2K12 Kub (SAM-6) air defense system made by the Soviet Union, but refurbished by the Houthis, with the help of Iran.
The substantial feature of the 3M9M missile is that it uses a solid-fuel jet engine and is equipped with a 1SB4M semi-active radar detector, which can intercept air targets below 7,000 meters altitude and airspeed. exceed Mach 1.8; Maximum range of 22km.
The improved versions of 3M9M missiles are 3M9M1, 3M9M2 and 3M9M3, the main purpose is to improve anti-interference ability and extend the range and altitude of air defense. The firing range of the last two models was increased to 24 and 25 km, and the anti-aircraft altitude was increased by 1,000 meters.
Yemen was equipped with the 2K12 Kub air defence system around 1979. At this time, all three types of improved missiles were functional and were widely exported by the Soviet Union; According to some sources, Yemen has imported relatively large quantities of this type of missile.
Since the Yemeni government army’s air defence forces joined the Houthi armed forces, after the Houthis took power in 2014, 2K12 Kub missiles in their hands and 3M9M missiles in stock, of course, fell into the hand of the Houthis. Although the missile stockpile of the 2K12 Kub system has been in stock for decades; Iran is the main ally of the Houthis is also using 2K12 Kub missiles and also improving 2K12 Kub; so they have no problem helping the Houthis to upgrade the number of missiles they have in stock.
Even if the number of missiles is not enough, they can be smuggled directly from Iran’s Revolutionary Guard. However, 3M9M series missiles must use continuous irradiation radar guidance, provided by the 1S31 fire control radar on the 1S91 Flush Radar vehicle.
If the 1S31 needs to lock the target accurately and in time, the 1S11 target search radar must provide the target coordinates early, to transfer the signal to the 1S31 fire control radar. However, as soon as the two 1S11 warning and reconnaissance radars are turned on, the radar warning receiver on the F-15 will immediately notify the pilot.
It is possible that the Saudi Air Force F-15s were damaged by Houthi’s missile this time, apparently not realizing that it was being tracked by the radar of the 2K12 Kub air defence system. According to the image from the 1S91 radar vehicle released by the Houthis on social networks, they have made frequency changes to the 1S31 fire control radar, to disable the electronic system on the Saudi F-15.

According to the information that the crew did not use radar to detect targets, but used opto-electronic observation equipment; Thus, the pilot F-15 of Saudi Arabia did not know that he was “locked to death” by the 2K12 Kub missile.
So most likely this time, the Houthi forces used a close-range combat method, that is, without turning on the fire control radiation radar and the target search radar; which only uses an opto-electronic sighting system to find and track the F-15.
The antenna of the fire control radar and the photoelectric system are linked together, and tracked by the photoelectric system; which means that the antenna of the fire control radar is tracking, but the radar is not on and does not signal; such that the F-15’s warning receiver will not issue an alarm.
As the F-15 approached, the fire control radar was suddenly turned on; To achieve this element of surprise, now the missile crew entered the “high voltage” mode, at this time the radar radiation had just covered the target and immediately launched the missile, causing pilot F-15 surprises.
But there are two prerequisites for this method of ambush, one is that the radar operator must be experienced and proficient in using it; so this force must be well trained, and it is possible that they are trained by Iran.
The second, but very important prerequisite is that the Houthis must find a regular flight path of the F-15 to build an ambush field; help the photovoltaic system to quickly find and capture the target, without the need for the results of the search radar.
And it is possible that the pilots of the Saudi Air Force were too subjective and based on their air superiority, to follow the same fixed route for each strike. Another tactic that Houthi could use is to leave the fire control radar on; but after the F-15 approached the fire zone, the 1S11 search radar suddenly turned on, quickly searched the F-15, guided the photoelectric observation system to capture the target, then the 1S11 radar turned off.
This method helps to reduce the difficulty of targeting the photovoltaic system; but for the pilots, even with high vigilance, it was certainly a surprise. The premise of this method is the same as the one above, that the crew must be well trained, synergistically proficient and understand the flight path of the Saudi fighter
It should also be said that this time, the Saudi pilot was quite lucky, the missile was in the state of chasing the plane, so it was detonated at the rear. And if the 57kg fragmentation warhead of the 3M9M missile explodes close to the target, either across the fuselage or tip of the nose, the F-15’s cockpit could have proved fatal.