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[ Intro ] [ Prereq ] [ Preparation ] [ CRW Canopies ] [ Landing Techniques ] [ Weather ] [ Accuracy ] [ Other Scenarios ]IntroductionGreat CRW parachute landings are not just a function of your final approach speed and flaring technique. They begin well before you even get into the aircraft. Hence, it is important to prepare for your landings on each jump. Also, given that the landing performance of a CRW specific canopy is not as good as standard elliptical and 9 cell canopies, it is important to spend a little time preparing for and learning about your first & subsequent CRW canopy landings. The focus should be maintained on every jump. PrerequisitesYou can and should learn most of the skills you require to land a CRW parachute on other canopies prior to taking up CRW. This means that you will only need to fine tune what you already know when you start jumping CRW parachutes. What should you know? The obvious thing is how to fly a parachute. You should have understanding and experience in all control inputs (risers, toggles, harness), all flight configurations (full drive to dynamic and static stalls), affect of flight in turbulence, various landing approaches (full drive straight in, deep brake, cross wind, keyhole), flight in traffic, etc. You should also have a basic understanding of weather (wind), spotting, and accuracy. PreparationPre jump preparation is vitally important to maximise your safety and enjoyment on each and every jump. What you know before you exit an aircraft will determine where you land, what conditions you land in, and the level of difficulty and safety of the landing area. These factors will also determine what technique you have to use for the landing area. For example, if you have a poor spot in gusting wind conditions, you may have to do a deep brake, vertical approach into a tight, rocky, uneven landing area on the lee (downwind) side of a hill. As far fetched as this may sound, why put yourself into that position. You should have a plan in your head for this and every other eventuality so that you know what to do prior to getting into that situation. It is also good to know the performance envelope of your equipment so that if you do end up having to modify your landing technique, you know how to do it safely. In contrast to the desperate scenario mentioned above, a well prepared jumper will end up swooping onto an open field free of obstacles and other dangers. There are many factors to consider which may seem overwhelming. But with a little practice the preparation can become very quick and efficient. So what should you know before you board the aircraft:
Peculiarities of CRW & CRW CanopiesThere are a number of categories of canopy designs available in the market today. Included amongst these are tandem, elliptical, cross braced, hybrids, rectangular, round, reserve (7 cell rectangular), 9 cell student, BASE, accuracy, and CRW. Within each of these categories is a wide range of aerodynamic characteristics that need to be taken into account. Most contemporary skydivers are brought up on 9 cell and elliptical canopies and they are unfamiliar with the flight characteristics of 7 cell canopies. As a result, they tend to use the same flying technique when they are first confronted with a 7 cell canopy. This can be dangerous. Can you imagine flying a jumbo jet the same way that you fly an aerobatic aircraft? So what is different about CRW canopies? Compared to standard ellipticals:
All this means that a CRW canopy does not perform as well as a standard elliptical canopy when comparing general flying characteristics. You should take extra care when flying a CRW canopy. On your first jump, brake off higher and practice flaring, planing, stalls and stall recovery, and use of all your control inputs. If you follow a few simple rules, you wont have a problem. If you brake a few simple rules. . . . . . If you are wearing large amounts of weight that is tertiary mounted, your landing safety may be compromised a little. In particular, when making a running landing without full flaring ability, your weights will tend to drag your body forward and cause you to overbalance and fall forward. You may have to use the option of cutting away the weights on each jump. Be very aware of where you are doing this if you pursue this option. Landing TechniquesAssuming you have spotted well and will comfortably make your intended landing area, the steps for a safer landing are: Setup For Final Approach: ensure the area around you is clear of traffic and that you will not hit anyone when performing the manoeuvres discussed in this section. Choose a landing point and a flight path that will get you there (allowing for wind, performance and flying characteristics of your canopy, traffic, and your intended technique). Plan to land into the wind is you will be able to generate the most lift in this direction. Speed Buildup: What does this mean? The speed that we want to eventually maximise is the forward speed of the canopy in its final planing (or flaring) stage. Speed equals lift. The greater your forward speed, the greater the lift you can generate and the better your flaring capabilities on landing. This obviously assumes sufficient space. You will not be able to do this in a tight landing area. To generate this forward speed during planing, you need to utilise your only available form of energy, gravity. So the cycle of speed generation begins with a sudden and sustained increase in descent rate until an equilibrium is attained where the canopy is fully pressurised (the airfoil is rigid and properly shaped), the suspension lines are under full tension, and the canopy and suspended load are descending at a faster rate. There are a number of ways to generate this speed increase on parachutes:
The amount that you pull down on any of your control inputs will determine the increase in speed. Basically, the more you pull them down, the faster you will go. When first starting out, do this higher until you learn what height is consumed during the manoeuvre. NEVER execute a speed increase at low altitudes. DON'T DO LOW HOOK TURNS. You should also be vigilant about maintaining grips on your toggles so that you can flare after increasing the descent rate. The Transition - Efficient Canopy Flight This is the period of change from high vertical descent to planing out. The wing performs most efficiently when there is minimal distortion to its airfoil shape and the airflow around it. The more dramatic the change of control inputs, the greater the disturbances. Hence, you should aim for a smooth transition. This is best explained using one of the scenarios from the speed build up section above. Lets look at the hybrid example. If you really snap the 180, you are more likely to suffer induced line twists, suspension line de-tensioning with resulting partial canopy depressurisation (the suspended load pendulum swings and momentarily goes back into freefall), and if you maintain this position the canopy wants to get back to equilibrium - which is the flight characteristics you started with. The better option is to give a toggle input that is a balance between maximum input and avoiding the pendulum & de-tensioning affect. Prior to the pendulum affect you should commence front riser input. The initial input can be quick. As you straighten out and approach a suitable height to begin your transition, smoothly and consistently let off front riser pressure. The objective is to create a curved flight path, not a dramatic 90 degree change from vertical descent to horizontal. When you have let off all front riser pressure, gradually introduce toggle input. Again, this should be smooth and consistent, not a rapid stab of the brakes. Once you can consistently perform this technique, you can introduce a transition from front risers to rear risers, and then to toggles if required. The key thing to remember is make it smooth, not dramatic. As far as the heights that you should initiate the turns, and transitions, they are different for different airfoils, wing loadings, weather conditions, altitudes, temperatures, pressures, canopy age, line trim, etc, etc. Hence, I can only suggest the following:
Weather & Altitude ConsiderationsThe ideal landing conditions include:
Altitude As altitude increases, the air density & resistance decreases. This basically means that as the elevation of your landing zone increases, your flaring ability decreases. You land harder as you get higher. Wind - Relative Motion of Air Masses CRW parachutists need to consider wind direction, strength and variability, and all forms & sources of thermal activity in their landing preparation. Excessive variability can be dangerous, especially when performing "radical" manoeuvres for landing. Jumpers should not attempt to land formations in high or gusty winds, high density altitudes, or high field elevations either. In fact, all CRW activity should cease when you encounter moderate to severe turbulence. Thermals Sources of thermal activity include: paved surfaces, plowed fields, and buildings. Depending on the conditions at the time, these thermals may contribute to the development of CN clouds. These thermals will be affected by prevailing winds. Avoid flying at low altitudes downwind of thermal sources. Humidity / Rain
Accuracy
Other Landing ScenariosIt would be pertinent to start this section with this advice: DO NOT ATTEMPT ANY OF THE FOLLOWING LANDING SCENARIOS. Try to avoid them in the first place. Planned Bi-Plane: The landing of canopy formations should be attempted by only those with a high level of CRW proficiency. Dual Canopies - Single Person: Main / Reserve Entanglements: Wraps: Entanglements: Other Formations:
Following are notes & other ideas relevant to this section that require further development. Please ignore.
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