1. What was "Operation Giant Reach"? I can find nothing on Google or anything else about it.

Operation Giant Reach was SAC's codename for European-based SR-71 reconnaissance gathering missions, during the Cold War.

2. What was "Operation Prairie Fire"? I can find nothing about this either.

http://en.wikipedia.org/wiki/Operation_Prairie_Fire

3. How do you shoot down the SR-71 in Hanoi Linebacker 2 scenarios with the SA-2! I can't seem to get a missile anywhere near those aircraft!

A tutorial YouTube video can be found at the bottom of the SAMSIM homepage.
http://sites.google.com/site/samsimulator1972/home
It was created by one of the best real SAM battery commanders, I ever met.
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Hpasp
Free SAM Simulator, "Realistic to the Switch"
(U-2 over Sverdlovsk, B-52's over Hanoi, F-4 Phantoms over the Sinai, F-16's and the F-117A Stealth bomber over the Balkans.)
http://sites.google.com/site/samsimulator1972/home

Book from the author - Soviet Nuclear Weapons in Hungary 1961-1991
https://sites.google.com/view/nuclear-weapons-in-hungary/
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