Troop parachute MC-6
The controllable round canopy parachute of the MC-6 is based on the main canopy of the FS-14 of the Smokejumper of the USA , which was introduced slightly modified by some special forces of the United States as SF-10A around the turn of the millennium . In the meantime, the same main parachute has been procured as the new MC-6 steerable troop parachute for all specialized forces in the USA. It uses the same T-11R reserve parachute and harness as the T-11 troop parachute . Its control and flight characteristics make the MC-6 clearly superior to the previous parachutes in the MC1-1 series.
FS-14 the Smokejumper
As early as the 1940s, the United States Forest Service (USFS) had tried parachuting its firefighters in the vicinity of the fire. In order to be able to land with all their equipment on steep mountain slopes, in small clearings and at great heights, they used controllable round canopy umbrellas from the start. Only the smaller Bureau of Land Management of the Ministry of the Interior is currently using flat parachutes for their own smoke jumpers. In the early 1990s, the USFS was looking for a new steerable round canopy parachute with automatic opening and decided on modified parachutes from the Quantum Series, which were originally developed as rescue parachutes for paraglider pilots . Designated as FS-14 (FS = Forest Service), these parachutes were introduced in 1995 in three sizes for the smoke jumpers. Depending on the jumper's weight, the equipment carried, the height of the landing site and the weather, one of the umbrellas is used. The aim is for the firefighter to reach his landing site with a safe rate of descent, but still quickly. The lowest possible sink rate is not advisable because a light jumper under a parachute canopy that is too large can easily be carried away by the wind. As a guideline for the use of the parachute variants, which only differ in size, apply:
| Cap size | Cap area | Load range | Landing altitude and ambient temperature |
|---|---|---|---|
| 8.53 m | 55.8 m² | 81 to 102 kg | 1500 m at 29 ° C |
| 9.14 m | 63.9 m² | 102 to 115 kg | 1500 m at 29 ° C |
| 9.75 m | 72.5 m² | 115 to 129 kg | 1500 m at 29 ° C |
The harness for the different sizes is color-coded, with blue for the smallest, olive for the middle and gold for the large parachute canopy.
With this advanced round canopy parachute, the Smokejumpers can land with their equipment with great accuracy in clearings or aisles the size of a house, even at high altitudes in the Rocky Mountains . The FS-14 main parachute is used together with the H-5 harness and the steerable reserve parachute FS-14R carried in front of the chest. The USFS has procured the main parachute in a blue color with white strips on the back and the reserve parachute in a red color. As a possible successor, the Smokejumpers are testing the more robust development FS-14Plus with improved sinking and gliding properties, of which 50 had already been purchased by 2011.
Special Forces SF-10A
In December 1998 the United States Army Special Operations Command , which leads all special units of the US Army , decided to independently procure a successor for their controllable round canopy parachutes. They were still using the now obsolete MC1-1 series, based on the T-10 parachute from the 1950s. Especially during jumps with full equipment, the weight of which the parachute is not designed for, and over high dropping points, the parachute was regularly damaged. In addition, the rate of descent was so high under these conditions that the risk of injury to the soldiers continued to increase. As the site for the selection process, the 1,800 m high landing site near Fort Carson , Colorado, was chosen, where in July 1999 the testing of six different parachute patterns took place.
Because the now proven FS-14 the Smokejumper was specially developed for these high-altitude scenarios and also had superior controllability, it was decided to introduce this parachute in the 9.75 m version. After adapting the glider to be able to use it under military conditions with the harness of the MC1-1 and the previous reserve parachute, the test was successfully completed. In the meantime, Irvin Aerospace had bought the rights to this product and sold the parachute, now known as the SF-10A, to the American armed forces and worldwide.
As part of a decentralized procurement of this non-standardized product, the SF-10A was introduced to special units. The 10th Special Forces Group took over this parachute as the first military user in 2002, which explains the name of the parachute (SF-10 = Special Forces-10). Other USASOC units have also successfully used this parachute as an interim replacement for the MC1-1 parachutes. The advantage of USASOC going it alone was the quick availability of a suitable parachute that was explicitly tailored to their requirements. However, USASOC was now solely responsible for the procurement and management of the SF-10A, which did not exist through the official channels of the US Army.
Troop parachute MC-6
In addition to USASOC, the other special forces, led across the armed forces by the US Special Operations Command (USSOCOM), had expressed their urgent desire for a replacement for the MC1-1. In order to meet this need and to introduce a standardized parachute, the USSOCOM, which like the armed forces has its own budget, looked for a suitable successor under the name Special Operations Forces Tactical Advanced Parachute System (SOFTAPS).
At the same time, the US Army went to great lengths to replace its obsolete MC1-1 and T-10 parachutes, harnesses and reserve parachutes. In September 2002, therefore, the USSOCOM and the US Army decided to bundle their efforts in the procurement of a controllable round canopy parachute with automatic opening. In order to save development costs and time, it was agreed to integrate the new reserve parachute and harness from the ATPS program, from which the T-11 troop parachute later emerged, to be used for the SOFTAPS. At that time, more than 40,000 jumps had already been successfully carried out by the USFS and USASOC with the FS-14 and SF-10A. The testing took place from 2003 on the Yuma Proving Ground and was ended without major difficulties. With new main risers, the main parachute SF-10A could easily be integrated into the harness of the T-11 and used together with the new reserve parachute T-11R. The development for both components was already completed and only briefly affected by problems when testing the T-11. That is why the first unit could be equipped with the parachute, now called MC-6 (Maneuverable Canopy 6), as early as 2006.
The main parachute is made by Irvin Aerospace and the harness and reserve parachute are made by Para-Flite - both are subsidiaries of Airborne Systems. All MC1-1 parachutes in the US armed forces have now been replaced by the MC-6. In April 2011 a total of 18,831 MC-6s had been introduced. Thereof 15,780 in the US Army, 675 in the US Navy , 107 in the US Air Force and 2,269 in the USSOCOM. All users have so far been convinced of the superior capabilities of the MC-6 and the jumping injuries with it have significantly decreased. However, a control line regularly breaks while the main parachute is opening. The reason for this is an inadequate packing process, in which a control line becomes tangled with the suspension lines or the main canopy during packing. During the deployment thrust, too much force acts on a single control line, which then breaks. Although this does not limit the load-bearing capacity, the usability of the MC-6 is severely limited. To solve this problem, after a test phase in 2013, the introduction of an improved main parachute with reinforced control lines is planned.
In 2011, Australia also decided to purchase the MC-6 for its paratroopers and special forces in addition to the T-11 military parachute . Further orders from abroad will most likely follow. With the US ceasing to be the primary user of the MC1-1 family of parachutes, widely used around the world, many armies around the world will be looking for a successor.
Construction of the main parachute
The parachute models FS-14, SF-10A and MC-6 presented so far all use the same main parachute. They only differ in smaller areas, such as the main risers, so that they can be used with different harnesses. In all three cases the parachute was introduced as a steerable round-cap parachute with forced opening initiation by a pull-up cord. Due to its superior control and gliding properties, it replaced older parachutes, which had reached their limits, especially at high altitudes and with a lot of load. The reduced deployment thrust, the low rate of descent with a higher glide rate and the steering and braking properties up to slow reversing are only possible because of the well thought-out construction of the parachute canopy. Thus, after dropping down, the parachutist can even head for small clearings with a high tolerance to wind strength and direction and land vertically on them. This property does not have a flat shield.
The main canopy consists of 28 parachute lanes with an enlarged base rim and 15 openings that generate thrust or allow control. At the lower end of the parachute canopy is the extra-wide base edge, which in turn is followed by the base net. The air that has accumulated during the opening process can escape in a controlled manner through the base net and prevents the canopy edge from turning inside out and the resulting line throw. The base edge is inclined slightly inward when unfolded and thereby stabilizes the parachute against pendulum movements. In addition, this base edge alignment creates a more favorable aerodynamic shape, which is further promoted by the six front openings. These openings adjoin the upper edge of the base edge and are located at a distance of one lane in the front half of the parachute. They reduce the pressure during the forward flight of the parachute and in wind and thus stabilize the shape. With the help of the base edge, they also ensure that the parachute can compensate more headwind when flying against the wind than it generates itself when driving forward without drifting backwards. The parachute's forward movement is partially generated by the three large rear openings above the base edge. They are closed with a mesh fabric to make this canopy area more stable despite the lack of material and to prevent other jumpers from falling through.
The main parachute has 28 suspension lines plus two control lines, which branch near the main canopy on each side into two central control lines for each control slot. The four central steering lines lead to a guide ring. Two control lines per control slot and an additional brake line for the brake slot at the two front control slots lead through this. While the parachute opens, each control line is held in position by two holding lines to prevent uncontrolled steering movements, which could lead to problems in this phase.
The parachute owes its very good controllability to the two open parachute lanes on each side. They are covered by wider and longer parachute tracks and only open to the rear, thus forming a control slot that can be closed with the control lines. The air flows up through the opening and is diverted backwards through the cover. As a result, almost the entire flow energy of the air acts backwards and the control slots are small and the increase in the rate of descent is kept low. To steer his glider, the jumper only needs to pull the control line into which he wants to turn. The control handles for this are located after the parachute opening on the back of the main risers. The pull acts via the guide ring on the control leashes, which are attached to the rear edge of the cover, and both control slots close at the same time.
While the air is trapped at the rear control slot in this braked state, it can escape at the front control slot via a smaller brake slot in front of it. Because in parallel with the closing of the control slots, parts of the parachute path in front of the brake slot are also pulled down via the brake line through the guide ring. The air can now flow out through this opening unhindered to the front. This creates a force that is exactly opposite to the other side, which enables the cap to be fully rotated in four seconds. In addition, these forces cause the parachute to turn flatter with less pendulum movements. If the jumper pulls down both control lines at the same time, so much air flows forward through both brake slots that he can stop the parachute in calm conditions and even move it slowly backwards.
Further developments
After the first successful sales of the military SF-10A to special forces, attempts were made to further improve the parachute system. For this purpose, the old harness and the reserve parachute T-10R and T-10R MIRPS used by the US units with the SF-10A main canopy were replaced by more modern models. The manufacturer's choice fell on a version of the low-level parachute LLP Mk1 developed for the British military for the harness and packing cover. In addition, customers were able to order this parachute, known as SF-10N, with the associated reserve parachute LLRP, which was later introduced into the US armed forces as T-11R for the T-11 and MC-6.
The main potential for improvement is the inadequate tensile strength of the control lines, which regularly resulted in broken control lines during the opening process, both in the smoke jumpers and in the US armed forces. While the military only wants to increase the tensile strength of the steering lines in the future, the Smokejumpers are testing a version that has been improved in many aspects with the FS-14Plus (also known as FS-14 +). In addition to the improved control lines, the new main canopy features a flatter profile for less susceptibility to wind and a higher glide rate, as well as a different canopy material. This absolutely air-impermeable rip-stop fabric with the brand name Soar-CoatTM has a silicone polymer coating and retains its properties even after a long period of time and intensive UV radiation . Furthermore, the design of the FS-14Plus has been simplified in order to facilitate manufacture and repairs. The changed material and profile gives the parachute a more agile behavior when advancing, braking and turning compared to the previous version FS-14 / SF-10A with unchanged high stability. The following data shows the comparison to the previous version:
| Parameter | FS-14 / SF-10A | FS-14Plus |
|---|---|---|
| Glide rate at 113.4 kg load | 0.8 | 0.92 |
| Descent speed with 96.6 kg load | 21.5 fps | 12 fps |
| Descent rate with a load of 192.7 kg | 19.1 fps | 17.3 fps |
Virtual parachute training
When purchasing the FS-14, the Smokejumpers also procured a parachute simulator to get the jumpers used to the control characteristics of jumping training before hanging under the parachute for the first time. The simulation model reproduces the image from the point of view of the jumper through enclosed glasses, while he hangs under a frame with the control lines in his hands in the harness. The simulation reacts realistically with steering, braking and pendulum movements to the control impulses of the jumper up to landing. In addition, environmental influences such as weather, wind and obstacles on the landing site can be included in the simulation.
Encouraged by the USFS, the special forces also procured this simulator for each Special Forces Group and had every soldier complete mandatory jumps with it before jumping with the SF-10A for the first time. Even with the introduction of the MC-6, the parachute simulator is used for retraining purposes.
Technical specifications
| Parameter | MC-6 |
|---|---|
| Parachute material | Nylon type IV, FG 504 |
| Weight of main parachute with harness | 13.2 kg |
| nominal diameter | 9.75 m |
| Max jumping weight | 181 kg |
| Max. Lowering speed | 278 km / h 150 KIAS |
| Min. Drop height above ground | 152 m |
| Max. Wind speed close to the ground for jumping clearance | 21 km / h |
| Sink speed with max. Jumping weight at sea level | 4.8 m / s |
| Glide rate | 0.8 |
| Forward speed | 16 km / h |
| time required for a 360 ° rotation | 4 s |
| Max. Swing angle | 8 ° |
| Suspension lines | 28 |
| Line length | 6.5 m |
| Packing cycle | 120 days |
See also
literature
- Headquarters, Department of the Army: Technical Manual for MC-6 Personnel Parachute System , Washington DC, 2009
Individual evidence
- ↑ History of the Quantum Parachute Series . Retrieved January 4, 2013.
- ^ A b National Wildfire Coordinating Group: Interagency Smokejumper Operations Guide , Boise, Idaho (2011)
- ↑ Parachute development for the Smokejumper . Retrieved December 20, 2012.
- ↑ a b MC-6 parachute development on Globalsecurity.com . Retrieved December 20, 2012.
- ↑ a b PEO Soldier Parachutes Briefing to Industry ( Memento of February 16, 2013 in the Internet Archive ). Retrieved December 20, 2012.
- ↑ a b Aerial Delivery And Field Services Training Facility Auditorium: 133nd Triannual Airdrop Review And Malfunction Safety Analysis, Fort Bragg (2010) p. 3ff
- ↑ Irvin Aerospace Inc: Users Manual For The Irvin SF-10A Parachute Assembly, Santa Ana, CA (2007) p. 18
- ↑ Australia procures MC-6 . Retrieved January 3, 2013.
- ↑ Airborne System: SF-10N Manuverable Troop Parachute System, Pennsauken, NJ (2007)
- ^ Airborne Systems: Airborne Systems Products, Pennsauken, NJ p. 9
- ↑ 16th AIAA Aerodynamic Decelerator Systems Seminar and Conference: Virtual Reality Parachute Simulation for Training and Mission Rehearsal, Boston, MA (2001)
- ↑ Virtual parachute training in the military ( memento from January 22, 2016 in the Internet Archive ). Retrieved December 21, 2012.
- ^ Headquarters, Department of the Army: Technical Manual for MC-6 Personnel Parachute System , Washington DC, 2009 pp. 2-18f