MY FANTASIES always ran to survival - after a plane crash I live on roots and berries and swim the Amazon to get help for the others; as a castaway at sea in a dinghy, I spear fish, fashion a sail out of my skirt and navigate my way to port.

Farfetched. I live in the middle of the city, phone the market for groceries and get my exercise doing sit-ups with other women in a gym. Then one day my dreams led me to sign up for a grueling three-week Outward Bound course in wilderness survival.

I picked the Southwest Outward Bound School in Gila Wilderness, N.M., where my course would include backpacking, camping and rock-climbing in a rugged mountain and canyon area.

At the bottom of the application I hesitantly signed the statement, "I understand that the program is a physically and mentally strenuous activity in a remote wilderness area far removed from the facilities of civilization," and immediately began worrying. At 30, could I survive such rigors; I'd never even camped before.

The OB people sent me a list, notable in its brevity, of clothing and equipment to bring. Under "optional" they listed toothbrush, a bar of soap and a change of underwear.

They suggested aerobics before the course began, working up to about twice the workout the average vigorous woman is supposed to get. I started running around the block every morning. They also advised cutting out tobacco, drugs and alcohol.

It didn't help. I was a nervous wreck when I finally stood in an open field in the Gila National Forest with 35 other equally tense students facing a bearded young man in rumpled khaki shorts.

He was Larry Campbell, the course director. He had graduated from Princeton with honors and from the Sri Auribindo Ashram with inner peace, and gave us a reassuring pep talk. "If you got off that bus on two feet, you can finish this course." Then he divided us into "tribes" of nine and introduced us to the instructors.

All Outward Bound personnel are clear-skinned, bright-eyed and have a look of tranquility. I still marvel that people who bathe so rarely can look so good.

Moe, the instructor for my tribe, wore wire-rimmed glasses, bib overalls and a faded purple tee shirt. Though he was 37 years old, tiny laugh lines around his eyes were the only clue that he might be over 25. He spoke so softly we had to inch toward him and slow our breathing to hear.

My tribe included Steve, a business man in his late 30s, Mark, a 22-year-old graduate student, and six assorted teen-agers; including the son of the president of Nicaragua.

OB provided all the equipment we needed, including packs, tarps, hard hats and climbing gear. Most important, they gave each of us a green plastic whistle tied to a shoelace. "Wear this around your neck," Moe said, "and blow it if there's an emergency."

With clothing, equipment and a week's supply of food, my pack seemed only a bit lighter than the average refrigerator. Since I couldn't lift it high enough to put it on my back, I sat on the ground, slipped my arms through the shoulder straps, pitched forward and staggered to my feet. I wobbled after the group as we began our trek up Turkey Creek.

The first days on the trail were very bearable. We moved slowly and camped near warm springs. The water was bathtub hot and neck deep, ideal for soakaing sore muscles. On the afternoon of the third day I was sunbathing on a rock after a long soak and I looked over at Moe and said, "I don't understand. I thought I was going to suffer." He didn't answer.

He didn't have to. For the next 10 days we moved over rough terrain at a rapid pace, and there were no more hot springs. We trekked trough nearly 100 miles of wilderness. We sloshed through creeks, clambered over rocks and fought our way through thick underbrush. We climbed steep grades on airless days, carrying an eight-pound gallon of water in addition to the heavy pack. We had three days of rain that left me without one dry piece of clothing. Nearly everyone in the group suffered from soggysock blisters.

But there were pleasures in tribal living in the wilderness. We would plunge into a mountain stream for an icy swim after a long, sweaty day of hiking. We sat around the fire at night exchanging back rubs. On cold nights we zipped our sleeping bags together.

When I had no dry clothies, Mark lent me his shorts and Pat lent me his belt to hold them up. One day when we were learning to tie a seat harness used in climbing called a swami, the group spontaneously broke into a chorus of "Swami, how I love you, how I love you."

Our food was supplemented occasionally by edibles we picked along the way and what we ate seemed remarkably nourishing and tasty, although at each weekly resupply we relished foods we couldn't carry on the trail - watermelon, fresh milk, eggs and bacon, English muffins, oranges. And we all developed strong cravings for meals that were impossible in the wilderness. Entire days' conversations were devoted to foods we missed. I wanted lime sherbet and lemon meringue pie.

The most remarkable deprivation at Outward Bound takes place during solo. The object of the solo is to give the student time to think by cutting off his usual outlets, like eating and moving from place to place. Each one of us was put on his own site for three days and given water but no food.

Many people, I am told, have dramatic revelations or profound experiences on solo. I didn't. The only thing that was revealed to me dramatically was the fact that a woman who doesn't eat for three days gets dizzy when she stands up too fast. I spent the time sleeping a lot. I was feeling so sweaty and stale by the third day that I used some of my precious drinking water to wash out my underwear.

Since I didn't feel especially hungry or lonely, however, solo was not an unpleasant experience. When the tribe picked me up after 72 hours, I was feeling calmer, more deliberate.

I lost that feeling as soon as we started rock climbing. It was supposed to teach us that we had strengths and resources we didn't know we had and to give us a sense of accomplishment. Mostly I felt scared. It was also supposed to be fun. I hated it.

Losing my nerve on a relatively easy climb, I pressed my body against the rock and wondered how I was going to get down. An instructor yelled up from below, "Bonnie, you're climbing like an amoeba."

Legs shaking, voice cracking, I called back, "I can't do this. I'm tired."

"Okay," he said, "let's think of all the reasons you can't climb that. You're tired. You socks are wet. Your feet hurt. You're just a girl. Any other reasons?

"No," I said wearily.

"Then move your right foot up about six inches, straighten your leg and finish the climb."

I finally found a toe hold and heaved my body over the top. I lay there gasping, sweat pouring down from under my hard hat. I told myself I would never rappel.

An hour later, I was preparing to rappel.

A rappeler must lean out, step backward over the edge of a cliff and slide down a rope. The first step, they said, was the hardest.

"Do I have to do this?" I asked weakly as I backed toward the edge.

"No" Moe said, and I stepped off anyway. They were right, the first step was the hardest. As calmly as I could, I slowly slid down to the ground. Part of the time I closed my eyes. At the bottom I was so relieved I wanted to cry. I would not, I whispered to myself, try gorge crossing.

By midafternoon, I was sitting on the edge of gorge trying to get up the nerve to cross it on two strands of rope suspended 80 feet above the canyon floor. The nerve I could't get up was to refuse.

I spent the entire three days we climbed in a constant clammy sweat, pushing myself from one terrifying situation to another.

Climbing is probably no more dangerous than driving on an interstate highway. The climbing activities at Outward Bound are safe. Qualified instructors supervise, and all students are on belay or firmly anchored.

I knew that, but I never believed it. I don't to this day understand my reactions. What I understand even less is that when I got home from OB, I signed up for local climbing classes.

Otherwise, I was beginning to feel at ease in the wilderness. I had learned to read a topographic map and use a compass, to administer first aid, to identify a couple of plants and to tie a few useful knots. I learned, too, that I could sleep out on the ground, unprotected, and nothing bad would happen to me. That's quite a lesson for a city person with the usual spider and snake fears.

I needed everything I had learned to get through the last phase of the OB course, the final expedition. Tribes separated and groups broke into smaller units. I was put into a group with three people from other tribes. The instructors gave us a map, a lecture on the dangers we might encounter (flash floods, hypothermia, lightning) and told us to get back to base camp within four days. If we were overdue by more than 12 hours, they'd come looking for us.

But the map was inaccurate, the trails were badly marked and the going wasn't easy. We got lost, found ourselves again and slept sliding down hills because we could find no flat places to camp.

We nearly made it, but we got lost on some jeep trail two miles from base camp.

As it began to get dark, we met another lost tribe and discussed our predicament. We considered blowing our whistles, but wondered if we had a bona fide emergency on our hands and whether we'd even be heard.

In the stoic Outward Bound tradition, we decided we were in no real danger, merely lost. We set up our tarps and prepared to spend an extra night in the woods. Since we had no water for drinking or cooking, we sat around eating dry raspberry gelatine mix and feeling sorry for ourselves.

The OB people found us the next morning and we suffered the disgrace of arriving back at base camp in a truck. We had a good meal and prepared to go home the next day.

Are the benefits derived from Outward Bound merely like the old joke about banging one's head against the wall, it feels so good when it stops? Yes and no.

Having explored the far ends of the aggravation scale, I now realize the triviality of most day-to-day irritation. I don't get annoyed when the water is slow bringing dessert.

And now that I've met up with a rattlesnake, there are few people who intimidate me