Nancy Reagan came out swinging yesterday over what she calls "character assassination" of her husband, Ronald Reagan, By President Carter.

The normally reserved wife of the GOP standard-bearer unveiled a new role she expects to play in the days between now and the election. She accused Carter of waging a "vicious and cruel" campaign against not only her husband "but the people he's [Carter] trying to frighten -- to put fear into their hearts is a terrible thing to do."

The former actress said she tried to ignore Carter's Chicago speech in which he said Reagan was trying to divide the country, or, as she put it, "North from South, Jew from Gentile, black from white." She said she tried to ignore Andy Young's remarks, and Patricia Harris' remarks, but they just kept continuing and she just didn't like it.

"I'm mad," she said, "yes, I am, and if you think I'm mad, you should hear my children. You almost have to tie them down, they're so mad."

Making a rare solo campaign appearance, Reagan was on her way to Syracuse for a fund-raising event co-starring her, Frank Sinatra and Wayne Newton last night. She talked on the plane, toying with a soft drink as she described her reactions to the campaign. She was impeccably dressed in a red and blue knit Adolfo suit.

She said she decided to say what she thinks after she realized that Jimmy Carter's vow to moderate his campaign rhetoric was temporary. "He said he'd stop, but he hasn't stopped," she said.

"The picture he's tried to create of my husband is absolutely untrue. He's [Carter] trying to paint this man as a warmonger, or as someone who would cut off Social Security for the elderly," she said. "There's no background for that in Ronnie's makeup to make anybody say that."

Of Jimmy Carter's claim that Ronald Reagan had promised not to introduce the hostages into campaign rhetoric, she said her husband "never promised anything of the kind." She called it another attempt to get away from talking about his record.

"Anything to prevent conversation about the record," she said, a note of exasperation in her voice. "It seems to me that the issues in this campaign are Mr. Carter's record, and those are the things that should be discussed."

Admitting that voicing her outrage publicly, at least, on campaign matters "really isn't my style," she said she decided to speak out this week.

After she taped an interview with "Good Morning America's " David Hartman to be aired this morning in which she made similar comments, Hartman expressed surprise.

"I've known David for a long time and afterward he said, 'Nancy I've never heard you like this before.' And 'i said, 'Well, I never felt like this before.'"

She told Hartman, according to a transcript of the taping, that "I'm now ready to respond. I deeply resent what he has said about my husband, the picture that he's trying to paint of my husband as a man, which has no basis in fact in his background, in his character, in his whole makeup."

She raised the hostage issue by demanding that Carter explain "why our country is regarded in the way it is by our friends overseas, who don't know if we're their friends or we're not their friends. Why our men have been taken hostage. Why they're left to sit there in Iran. And why, if you plan a rescue mission, why can't you plan it well? I think even I would know better than the way it was planned.And we lost eight boys."

She told Hartman that Carter was using scare tactics because "that's the most effective weapon that there is, particularly with women. When you scare them and [they] think that their sons are going to maybe go to war, that's a very powerful weapon and a very unfair weapon. You just don't fight like that. Campaigning is very character-revealing. How you choose to fight your battles is very character-revealing."

During the flight, she said she wanted Jimmy Carter to explain why so many people are unemployed, why inflation has reached such proportions.

Of Ronald Reagan's so-far secret plan to gain release of the hostages and end the war between Iraq and Iran, she was momentarily flustered. Reminded of a similar secret plan to end the war in Vietnam that Richard Nixon had during the 1968 campaign, Nancy Reagan would only say what she says Ronald Reagan says. "You don't negotiate in the press or in public. You may have you own ideas, but you don't talk about them publicly."

She said she thinks the way people campaign tells a lot about them, but she stopped short of commenting on whether she thinks Jimmy Cater is an immoral man. "I'm not going to comment on whether someone is moral or not."

Asked if she thought Carter lacked principle, she replied: "I don't like the way he campaigns."

She became angry when it was memtioned that Carter called Ronald Reagan's foreign policy ideas "naive."

"Well, let him explain why so many ambassadors of ours are kidnaped or killed. That never happened before," she said.

Sometimes Carter's characterizations of Ronald Reagan have made her so angry she has cried, she said.

She said that she had mixed feelings about wanting her husband to be president and if he loses, "it won't be the end of our lives."

She said she told her husband only yesterday about her own new campaign tactics and that he was surprised.

"He was in such a hurry, and I talked so fast, that I'm not sure I got his blessing," she said, laughing.