The MC1-1 parachute, commonly called the Dash 1, is the U.S. military's static line deployed steerable troop parachute. Currently, there are two versions, the MC1-1B and the MC1-1C, in service. The Dash 1 is used less often than its non-steerable counterpart, the T-10C, because its forward motion and steerability increase the chance of mid-air collisions between jumpers. It is similar in size, shape and weight to the T-10C, and both the parachutes utilize the same pack tray, static line/D-bag, and harness assembly. The steerability of the Dash 1 is achieved through the removal of several panels at the rear of the canopy, which provides a forward drive of about 9 miles per hour. The parachutist can turn by pulling on toggles which attach to two control lines. The control lines change the shape of the opening and allow turns to the left or right. Some features of the MC1-1B are:
- 35 foot diameter, parabolic canopy.
- Weight of ~30 lbs.
- 30 suspension lines with a length of 25.5 feet and a tensile strength of 375 pounds each.
- Rate of descent is between 18 and 22 feet per second, depending on the weight of the parachutist.
- Attached to the T-10 harness by 4 nylon webbing risers. The control lines are routed through the two rear risers.
- 100 sq. feet of canopy is removed from the rear, creating a 9 mph forward drive and 8.8 second turn rate.
- Repacked every 120 days.
The MC1-1C is the same basic design, with the following differences:
- Suspension lines are 22 feet long.
- It is made of non-porous material, slowing the descent rate to 14-18 feet per second.
- Turn rate is 7.7 seconds.
- The rear opening is 60 sq. feet in area.
Like the T-10C, the MC1-1B/C canopies feature an anti-inversion net to help eliminate malfunctions. They can be used from a minimum height of 435 feet to a maximum of 10,000 feet. The T-10 troop chest reserve parachute is used as a backup in case of a main canopy failure.
Source: US Army FM 57-220 Static Line Parachute Techniques and Training.