Everyone knows many NFL stadiums have retractable roofs, but have you ever heard of any having a retractable field?
Well, now you can say you have after the Arizona Cardinals transformed their field into retractable turf.
And, the NFL had its own retractable natural grass turf installed specifically for the Super Bowl.
Where did the grass come from?
The Tifway-419 Bermuda hybrid grass came from sweet home Alabama, and was moved in and out of the stadium, according to Sports Illustrated.
The first debut of the grass was installed in time for the Pro Bowl, but after the game was over, the grass was moved back outside for more sunlight.
The retractable field was first built in 2006, and the 19-million pound tray holds 92,000 square feet of turf, drainage and its own irrigation system.
The tray rests on 13 tracks and moves through an opening through the end zone. Sitting on 546 wheels, the field moves at a top speed of one-eighth mph.
The field irrigation system works on customized timers, with 1-inch deep mat and piping for drainage.
A few facts:
- The grass field rolls out of the stadium on a 18.9 million pound tray, residing outside of the stadium except for football and soccer events, is the first of its kind in North America.
- The grass field remains outside the stadium in the sun until game day getting the maximum amount of sunshine and nourishment, eliminating humidity problems inside the stadium and providing unrestricted access to the stadium floor for events and staging.
- The site has the stadium situated along a slight northwest to southeast axis for maximum sun exposure for field in the outboard position.
- The roll out field travels at a speed of 11.5 feet/minute (1/8 mph); it takes approx. 75 minutes to travel approximately 741 feet.
- The field is 234 feet wide x 403 feet long and 39 inches tall.
- Field tray rests on 13 rail tracks and moves in and out of the stadium on 546 steel wheel assemblies (42 rows).
- 76 of the wheel sets are powered by a 1-horsepower motor (total = 76 horsepower).
- The field will support approximately 94,000 square feet (over 2 acres) of natural grass.
- The grass is Tifway-419, a Bermuda hybrid. It was planted by using stolons, or plugs, that provide long-term field conditions.
- The tray has an irrigation system that works on timers and can be customized. The water will drain through a 1-inch-deep mat and several pipes that lead to a main drainpipe underneath the field tray.
- A few inches of water will remain in the tray while the field is in play to keep the grass moist.