Schwarzkopf portable roller coasters were very popular in the 1970's, becoming staples of fairs, boardwalks, amusement parks and even theme parks. The small footprint of the rides and the ease of installation made them a great crowd pleasing attraction. Most theme parks would replace them with full sized permanent coasters as time went on, making them more and more rare through the decades.

Great Adventure's Jumbo Jet roller coaster is perhaps the most mysterious attraction in the park's history, with very little imformation existing on the ride and its short stay at the park.  The ride was introduced as part of the Fun Fair section of the park in 1975. 

The Jumbo Jet was leased from Willy Miller's Continental Park Attractions along with several of the other rides in the Fun Fair section. The lease included an option for the park to purchasse the rides if they wished to keep them. The ride was assembled in the spring, and by all accounts sat idle for weeks.
Technical Information
Ride Model: Jumbo Jet III
Ride Manufacturer: Schwarzkopf
Number of Cars: 8
Capacity per Car: 6 Guests
Hourly Capacity Approx. 2000 Guests
Depth of Ride: 194 ft
Width of Ride: 108 ft
Height of Ride: 56 ft
Length of Track: 2854 ft
Weight of Ride: Approx. 170 tons
10- 40 ft Containers
Features: Brakes and retractable anti-rollback devices
Entrance and Exit stations
Cars are "elastic" with moving motors
Electric spiral lift without chain elevator
According to all the information available at this time, the Jumbo Jet never operated or opened to the public while it was at the park.  Currently no reason is known for why the coaster never opened. Dozens of the identical model coasters have operated around the world, and some continue to operate to this day.

The Jumbo Jet was removed midway through the 1975 season, and the Super Cat ride was brought in as a replacement in July of that year.