A report by The New York Times (NYT) touched on a video Iran circulated on February 4 whereby it unveiled a new underground Iranian Air Force base called Eagle 44. A poster with fighter jet silhouettes was hidden in plain sight on the wall, with one jet, in particular, standing out, according to the paper. It was shaped like a cutting-edge military jet, which Iran does not currently have, but officials claim that Russia is in the process of selling it to them, the paper claimed.

Satellite imagery analysis also reveals an at-scale model of the same type of fighter jet at the base, which experts refer to as a "mockup". According to NYT, two things indicate Iran's intentions: Officials are optimistic about the delivery of these planes, and they may intend to house some of them at this air base.

Iranian military and political officials have publicly touted the expected purchase of Su-35s, which is considered one of Russia's most advanced combat aircraft, since September 2022.

The details in the video and satellite images suggest that Iran is at least preparing for the planes' arrival, which officials say will be later this year, according to the NYT, even though Russia has not confirmed the agreement. If went through, the nation's fighter jet fleet would receive the biggest upgrade in decades.

This comes as Russia's Western-induced isolation furthered cooperation between Moscow and Tehran at different levels. The Biden administration responded to the situation by calling the ties "harmful" and claiming that Iran is allegedly already receiving training for the new aircraft without providing any evidence. White House Spokesperson John Kirby stated that "these fighter planes would significantly strengthen Iran's Air Force relative to its regional neighbors" at a news briefing in December.

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A former US government imagery analyst and senior director for Mission Applications at HawkEye 360, Chris Biggers, suggested that there are "two mockups of combat aircraft" at the base, including one that looks similar to the Russian Su-35. “These are likely being used in assessing clearances for maneuvering the aircraft throughout the underground facility and could suggest they’ll be based here,” Biggers wrote.

Biggers said the second mock-up aircraft is one that the Iranian Air Force currently has on hand, adding that “the Su-35 is not, but is expected in early 2023 as Tehran continues to support Russia’s war in Ukraine."

Both probable mockups, according to the NYT, showed up at their current location in January while base construction was still going on. The Times' review of satellite images shows that they haven't been moved since, suggesting that it's possible that the air base is still undergoing some improvements in anticipation of the potential delivery.

A tunnel entrance that can be seen in the video may be too small to fit the wide Russian jets. However, the NYT's analysis of the location reveals that work is still being done on a different tunnel, possibly for bigger planes.

The Iranian video analyzed by the NYT and Biggers was one of many press releases Iran issued last week to promote Eagle 44. It displays senior military officers touring the base.

According to Biggers, the main fighter jet's silhouette on the poster in the video is a "flanker series jet," a term used to describe contemporary Russian fighter jets like the Su-35. Iran does not currently possess any of those types of aircraft, but the other silhouettes depicted are of actual, older Iranian aircraft that are still in service.