You want a sim that's IMO is better than the "new" wilco one and won't cost you a penny then do a search for BAO Tower.
It was released in 1995 and does a grand job. A shame it was never developed beyond it's intial release.
You may have some difficulty getting it to run, though I manged on XP. I have never tried to get it running on Vista +
{look at that, after 7 years this is my 100th post!
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