reporter: cheryl took her daughter to this nearby ramada inn. she never heard from joe again. the next morning this is what cheryl drove up to. the morning of the fire, they took refuge at a neighbor s home. it would be there that she would discover the fate of her husband on the local news. they interrupted the house fire to show that a plane had crashed into a building. reporter: how did you react when you realized it was his plane and it was him? well, i don t think i did react. i think i was just just in complete and utter shock.
joe stack knew exactly where he was going, the echelon building in austin, which housed the irs. it was like a fireball. people let out a scream all around you. people were crying. reporter: stack slammed his plane between the first and second floors of the building. it exploded on impact. one man in the building was killed, vernon hunter, an irs employee. immediately, there were fears that this was an act of terrorism. but it wasn t. it was simply one man s grudge against the irs. and then came the manifesto. before stack would die by suicide, the 53-year-old software engineer would leave behind a rambling diatribe online, where he railed against the government in excruciating detail.
reporter: it took some time for cheryl stack to get to this point. for two years, she has struggled. but has found comfort in her music and her faith. i have been more sad than mad. suicide is so painful on so many different levels. then you add the public factor, the public suicide. reporter: it was february 18, 2010. an angry and violent joe stack set his family s house on fire, then drove here to the georgetown municipal airport, boarded his single engine plane. ready for departure. reporter: and was cleared for takeoff. 39 delta, cleared for takeoff. what s your direction of flight, sir? reporter: at 9:44 a.m., joe stack was headed for his final flight.
both loved music. cheryl played piano, joe played bass guitar. two years later, in a small ceremony in austin, they married. joining them was cheryl s 12-year-old daughter, margo. did he ever talk about how he was angry with the government, angry with the irs? when we were dating, he did talk about the irs. he didn t seem so angry. he just didn t like them. reporter: but actually, joe s emotions ran much deeper. in the 80s while living in california, he was part of an anti-tax movement, even forming his own tax exempt home church. his run-ins with the irs continued for decades. joe and cheryl got audited in late 2008, and once again, joe was in another battle with the irs. a battle he wasn t going to lose. joe stack started to document
the government in excruciating detail. i choose to not keep looking over my shoulder at big brother while he strips my carcass, he wrote. i choose not to ignore what is going on all around me. i have just had enough. today, that manifesto still haunts cheryl stack. what do you say to people that may be listening to you and thinking, how could she not know about this rage, about this manifesto, about this anger? i knew that he was angry, but i thought he was angry at us. about the irs, i didn t know that he was violent. how could i possibly know he would do a thing like that? cheryl met joe stack through a mutual friend in 2005. both loved music.