Harm says the Mig-29 is a rip-off of the F-14 Tomcat. The Mig-29 was invented by the Soviet Union as a counterpart to the F-16 and and F/A-18.
As far as can be searched, there's no real "Hotel Posolskaya". Posolskaya is a rural locality in Kabansky District, in the Russian Far East not Moscow.
Harm says a Mig-29 has a range of 1,500 miles if both tanks are full. At best search, the ferry range - which means one pilot - of a Mig-29 is 1,300 miles.
Mac tells Harm the local time is 0525 when he wakes up. That would mean 0225 Zulu. On the screen earlier, the time was 0220 acceptable as Harm was dreaming. Later, during the secure line call, Admiral says it's 0400. That is wrong as time Washington DC time would be 2125 or much later the previous day.
Ham and Mac towards the end are shot down by Russian fighter jets. Those were clearly not Russian; they were the fictitious Mig-28s, in reality F-5s from Top Gun (1986). JAG (1995) often uses archive footage from Paramount movies as they are from the same company.
Harm and Mac steal a MiG-29, but the plane shown flying along the river is a SU-27.
Harm asks Alexei how far it is from Norilsk to Beloyka. Norilsk is a real city in the arctic north of Russia. At best search, there's no place in Russia called Beloyka. There's Belovka, Russia but in western Russia.
Major Viktor Lushov met Harmon Rabb Snr in Vorkuta. That is not in Siberia but in northwestern Russia, on the Vorkuta River. Yes, there were gulag camps there.
Lushov could not have been working for Consolidated Aircraft. In 1943, Consolidated merged with Vultee Aircraft to form Consolidated-Vultee Aircraft or Convair.