Racing to You by Susan Carlisle

The last person she wanted to ask for help is the man who destroyed her father’s life.
Hot air balloon pilot Emily Kerr needs to enter a coast-to-coast race across America to raise funds and start her own ballooning business. Her only obstacle is finding a sponsor.
Reid Martin is an industrial textile manufacturer who has developed a promising high-tech material, but he needs to test it in a practical setting before selling it to the Department of Defense. With a government contract in hand, Reid can take his family company public, saving it from bankruptcy.
Despite her reservations, Emily offers Reid an enticing opportunity to get a first-hand look at what his fabric can do. He agrees to help the intriguing woman but with two stipulations:
1. She must use the balloon he constructs
2. He will accompany her on the three-week trip
While floating across the sky, Emily reluctantly accepts the appealing man’s presence while vowing not to let him touch her heart. Will Reid risk everything—including Emily’s dream and his hope of winning her love—to save his future?