Luis Carbonetti, who played in two Champions Tour majors in 2005, carded an even-par 72. He shares second place with Bill Longmuir, Nick Job and Bob Ralston on the Champions Course at PGA Southern California Golf Club.
Jaeckel, who won the 1978 Tallahassee Open on the PGA Tour, got off to a quick start with back-to-back birdies from the 10th. He stumbled to a bogey on the par-three 15th, but parred the next three to turn at minus-one.
He carded his third birdie on the second.
Jaeckel, whose best finish on the Champions Tour was a tie for 10th at the 2000 Mexico Senior Classic, moved to three-under with a birdie on the par-five fourth. However, he stumbled to another bogey on the par-four sixth before parring out for the first-round lead.
'Very difficult conditions out there today,' said Jaeckel, who is teeing it up in the Champions Tour Q-school for the seventh time. 'The Santa Ana winds made the first couple of holes on the back nine and the last couple on the front nine difficult. You better have taken advantage downwind and hope you didn't have a train wreck on the tough holes. I was able to get through that today, but that's not to say it won't happen any other time.'
Carbonetti birdied the first, but tripped to a bogey at the third. He got that shot right back with a birdie on the par-five fourth. He fell back to plus-one after bogeys on eight and 13. The 52-year-old got back to even-par with a birdie on No. 16.
Longmuir got off to a fast start with three birdies in a four-hole stretch from the second. Unfortunately, he faltered to a double-bogey on the sixth. Longmuir stumbled back to plus-one as he bogeyed 10 and 12. He got one stroke back with a birdie on 13. Longmuir bogeyed 15, but came back to birdie 16 to share second.
Ralston posted two bogeys and two birdies on both his front and back nines.
Job played the back nine first and carded three bogeys. After making the turn, he posted back-to-back birdies from the fourth and also birdied the par-five ninth to end at even-par.
Scott Masingill carded a one-over-par 73. He was joined in a tie for sixth place by Jon Chaffee, Tom Herzan, David Lundstrom and Chris Starkjohann.