During the fightings between India and Pakistan in early 2019, there was an episode where the Indian side claimed that their MiG-21, developed in the mid-20th century, allegedly took down a modern Pakistani F-16 multirole fighter. Although the statement was hard to believe, neither the Pakistani side nor independent observers were actually able to reliably refute it.
One would have hoped that data from U.S. satellites would clarify the situation, but this did not happen. The Americans did not publish any materials, including satellite images, that could provide additional information in this case, as noted by The War Zone back in 2019. This dated article appears in a new light in the context of Washington's recent access denial to satellite services for Ukrainian users, now reverted to normal.
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To begin with, let's recall the background. From February 27 to March 4, 2019, India and Pakistan had cross-border clashes, which involved heavy artillery and aircraft, although did not escalate into an all-out war. The episode in question happened on February 27, when a large-scale air battle broke out, with eight combat aircraft (2x MiG-21, 2x Mirage 2000, and 4x Su-30MKI) engaged on the Indian side, and as many as 24 aircraft from Pakistan, including eight F-16s.
Afterwards, India claimed its MiG-21 shot down a Pakistani F-16 fighter, but then the heroic aircraft itself was destroyed by an enemy JF-17. It should be clarified that both fighters (i.e. the MiG-21 and the F-16) fell on Pakistani territory — this detail only added to the media chaos that followed the statements of both sides of the conflict.

For example, at first, the Pakistanis stated that the Indian side was outright lying, for one reason, because the Pakistan Air Force that day allegedly never used F-16s at all. But the Indian side later showcased fragments of an AIM-120 missile as evidence that Pakistan did use F-16s on February 27, 2019.
Then, Pakistan said they had found the wreckage of the downed Indian MiG-21, and its examination allegedly showed none of the four air-to-air missiles mounted on this jet had been fired, hence it could not have shot down the F-16. Here, once again, since the aircraft wreckage was discovered on Pakistani territory, the statement was not largely perceived as 100% reliable.

The above fragments of debate clearly show why even nine months past the incident, the question of whether the MiG-21 really shot down the Pakistani F-16 remained open as of December 2019.
Amid this exchange, the TWZ authors wondered if the United States could dot the i's and cross the t's by publishing the data gathered by its infrared satellites. If anything, this would be beneficial since it was also about the reputation of American-made weapons: as a fourth-generation aircraft, the F-16 was supposed to be undefeatable to a MiG-21 from the third generation.
However, as the authors of the portal further summarized, despite the ability to do so, Washington chose against publishing any data that could clarify what happened in reality. One possible explanation is that the White House decided not to intervene for its own geopolitical motives.
Therefore, Defense Express adds, even 5 years later, the mystery of whether the Indian MiG-21 was able to shoot down the Pakistani F-16 remains unsolved.
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