Para Ski, Para-ski powered parachutes, Paraski powered parachute flight report.
The following can be found at: http://www.paraski.com/reviews_aero.htm
By Martin D. Ignazito
On December 21, 1998 Joe Albanese of ParaSki International brought a ParaSki to my local airport near my Home in Charleston Illinois specifically for me to examine and test fly. Our local airport is Coles County Airport (MTO). The weather precluded any flying being rainy, cold and very windy (drat), but the following are my impressions of this machine from the example I saw that day.
All 4 wheels are 8" aluminum with 16-650X8 ribbed, flat profile tires. These tires are much larger than those used by most in the industry. The wheels are fitted with ľ inch ID "standard" (wheelbarrow type) bearings. The vertical steering spindles (kingpins) use tapered roller bearings instead of metal to metal "bearings" like other powered parachutes. Steering linkages use Heim fittings with grease zerks at both ends. Suspension at all 4 wheels is via rubber in shear torsion springs on a trailing link axle mounting system.
The ground steering mechanism is a snowmobile or motorcycle type handlebar affair with the steering shaft mounted on split nylon bushings. The ground steering is coupled with the magnificent rudder in the propwash. The chute steering line pedals are adjustable in 8 steps of about 2" increments to accommodate varying pilot leg lengths. The steering foot levers or pedals are arranged with a series of three pulleys to give a 4/1 motion amplification of foot travel to the steering lines instead of the "traditional" long steering lever like most PPCs. Handgrip rings attached to the "home" end of the steering lines are used to "reel in" the steering lines for chute collapse or extreme final approach "braking" and touch down. The controls are well thought out and ergonomically laid out. The interior of the cockpit or fuselage is painted with "Zolotone" enamel. This is a speckled finish paint used to paint the interior of car trunks and such. It looks quite good in this application, covering the "business" of the exposed interior structure. The semi-enclosed cockpit is well finished and comfortable. The instrument panel is just that, a true instrument panel located right where it needs to be for good pilot viewing.
The chute is stored in a compartment beneath the rear seat. The rear seat is hinged at its front edge to act as a door for this compartment. This space could be used for baggage during flight or at other times if the chute is stowed outside the compartment e.g. on top of the rear seat. Buckeye, Six-Chuter and other traditional style powered parachute pilots might be hard pressed to pack the chute tight enough for this compartment. Para-Ski people are chute riggers and find this to be duck soup I'm sure. Others not accustomed to chute rigging and packing might stow the chute on top of the seat and store their lunch or other condiments in the ample compartment below electing not to attempt to "stuff the noodle up the wildcat" using the small chute bag. There is an ample front glove box at the front of the pilot's seat with a door to secure the contents.
The engine is mounted on 4 smaller versions of rubber and steel automotive type engine mounts. These are motor mounts used in snowmobile applications for the same engine used here. The engine in the machine I saw was a 75 hp Rotax 618. Rotax twin radiators were used on this example. These are being replaced on later production models with the newer and larger single radiator configuration. There have been numerous reports of "hot running" with the older Rotax twin radiator setup.
This unit is fitted with a Rotax "E" gearbox at a 3.00/1 ratio and a six bladed 66" diameter Ivo prop. This is the largest prop that Para-Ski prop cages will accommodate. An impressive bundle of sticks indeed. It looked like a giant Vegimatic or bologna slicer.
Fuel and oil tanks are of welded aluminum construction with external sight gauges. The fuel tank is streamlined for reduced drag and prop inlet flow restriction. A nice touch and typical of many things on this machine. The oil reservoir is fabricated from the same square aluminum tubing used to make the front and rear suspension "axles". A pipe nipple with schedule 40 plastic pipe cap is used for filling on both fuel and oil tanks. There is a clear plastic tube sight gauge along each tank.
The airframe is suspended from the chute flying cables via a single rapid link with 6 cables going to points on the airframe. Front axle, prop cage just above engine level and rear axle. The pivot point is higher above the CG than on other PPCs giving a more stable nose attitude and less propensity for "rocking" in the nose up, nose down direction. It is also claimed that CG location has less effect on nose up attitude with this arrangement.
The entire airframe is of welded 6061 aluminum tubing both square and round. The all-welded frame is rigid as a bridge girder. The prop cage, and indeed all frame parts, feel rock solid when grasped by hand and wiggled in comparison to bolted tube frame construction as used by others in the industry. Of course welding 6061 aluminum to make repairs is not for the timid, but this is not as much of a problem as it was years ago. In our area I know several farmers who can do this work as well as several welding shops. In fact I believe I could do it with a bit of refresher training having done some inert gas welding years ago.
Overall quality of construction, fit and finish is absolutely first rate throughout.
The magnificent torque compensated propwash rudder stretches vertically the entire diameter of the prop cage (about 72" or so) just behind the propeller. It is indeed a work of art with torque compensating offsets top and bottom and a smooth transition section in the middle between the two halves. It is of all aluminum construction and is linked to the ground steering controls via a single push/pull cable arrangement. Water rudders are linked to this rudder for water operations when floats are fitted. The beautifully designed and fabricated rudder should allow for crosswind landing capabilities well beyond the means of the rest of the powered parachute community. I have yet to try this feature, but look forward to it. With steering foot controls the wing can be canted into the wind while opposite rudder is used to line up the cart with the runway setting up a "side slipping" approach similar to that used in fixed wing aircraft. Crossed controls are held till touchdown at which time rudder is released before the steering wheels touch down and then a chute collapse is initiated. This is all conjecture on my part of course, since weather conditions precluded a flight test. Joe confirmed that this is the crosswind technique for this machine using the wonderful rudder. I can hardly wait to try it out. In my opinion, every powered parachute should have this feature. Crosswind landing safety would be much improved. Of course this would require some training for those not familiar with the technique, but the benefits are worth the effort. Joe could not quote a demonstrated crosswind component limit since this uncoupled rudder is a new feature. Prior to about 2 months ago, the rudder was coupled to the foot steering with limited override capability. This uncoupled arrangement is far superior in my estimation. Of course my GA background in three axis control airplanes makes me a bit prejudice. Para-Ski needs to take this light out from under the bushel and talk about it more. It is clearly a significant control advantage that is lost on the PPC market place from lack of discussion. I also suspect it is not well understood by most PPC pilots who have little or no exposure to rudder use.
Para-Ski's promotional video shows a crosswind landing being made which would test the limits of most powered parachutes. When the chute is collapsed after this landing, the entire canopy falls in a neat accordion like pile on one side of the machine with the entire chute off to one side outside of the rear wheels. A neat trick indeed and this was with the old limited override rudder.
The magnificent and well-engineered rudder alone almost makes the higher cost of the Para-Ski worth the added bucks when compared to other PPCs on the market (in my humble opinion of course). When you add to that the neat glove box, chute/baggage compartment, 4th wheel, 4 wheel independent suspension, all welded extremely rigid airframe, semi-enclosed cockpit, fully adjustable foot controls, well placed instrument panel, tapered roller bearing front spindles and the fact that no assembly is required, the added cost seems to be well justified. True, the bottom line ticket price is high, but good stuff costs money. I'm hooked, I think I gotta have one.
Due to the bad weather at the time, I did not get to fly this machine. My overall impression however, is that this is a first rate piece of work. Although I had seen a number of pictures, the machine is more striking in the flesh than the pictures reveal. The big 66" prop with its 6 blades and the wonderful rudder are striking when first seen. Engineering details are first rate. The quality of it and finish is also first rate. A magnificent flying machine indeed. Joe has promised me a turn at the controls when we meet at Sun-N-Fun in April. I will not sleep well till then. I'll follow up with some flight impressions after that. Meantime, this looks like a hot prospect for those seeking something out of the ordinary in a powered parachute.
Part 2: A 2nd Impression
Since writing the ‘First Impressions’ article about the Para-Ski back in December of 1998 (see May 1999 Aero Connections issue page 61) when the weather precluded any flight-testing, I have had the opportunity to fly a few examples of this machine. So far I have flown three different two-place Para-Ski configurations consisting of a 420 sq. ft. chute with Rotax 618, a 656 sq. ft. chute with Rotax 582 engine on an earlier model example, and most recently a 520 sq. ft. chute with Rotax 618 engine. My impressions of the Para-Ski in operation are as follows:
Since there is more "stuff" on a Para-Ski like another wheel, a cockpit enclosure, enclosed compartments, two wheel steering, 4 wheel suspension system, rudder and it's controls, more flying cables, lower prop
guard, more steering pulleys, etc., a thorough preflight inspection takes a couple of minutes more than on the usual PPC. I am a stickler for this sort of detail, and before one of my Para-Ski flights while doing my preflight inspection, Joe Albanese of Para-Ski was moved to ask me "do you ‘always’ do this before every flight?” "You bet your sweet posterior ", was my reply. While one is aloft, it is not the best time for discovery of what should have been found in a good preflight.
Having completed a preflight, it is time to layout the chute. Although pretty much the same as on other PPC’s, there are a couple of minor differences. Para-Ski uses a sheet metal chute compartment to store their chute. Being small by other PPC standards this compartment requires a packing procedure that is unique to say the least. The chute is laid out and rolled into a very compact package. Although this takes a bit more time to pack, it makes the layout go faster since the chute is well organized for rolling into place with this packing method. A pair of Velcro straps are used to hold the chute lines up on the prop cage prior to take off. At kite up, these straps release the chute lines; a neat, no wear, no snag, lightweight solution.
Although basically conventional, the kite up and take off are a little different depending on the version of Para-Ski you are using. The gigantic 656 sq. ft. chute was a real handful to get kited up, and even threatened to start a rollover early on in a crosswind. This is not a chute for a windy condition take off. The excellent two-wheel ground steering, rudder, and four-wheel cart, allowed me to reduce thrust and steer under the chute to avert a rollover even though the wheels on one side had begun to lift. After re-stabilizing the kite up run, I was able to power up and get off in a more or less normal way.
Joe Albanese of Para-Ski International indicates that this machine was an earlier version with a narrow track and high center of gravity making it a bit less stable in rollover than later models. Even given that, it was controllable in less than ideal conditions. The 520 sq. ft chute behaved about like the usual PPC with this size chute, kiting up at speeds similar to most PPC’s. The excellent ground steering and rudder made for a very confident feel. The 420 sq. ft. chute was a bit of a revelation, this thing is FAST by usual PPC standards and requires a high taxi speed on the order of 20 mph just to initiate kite up. Take off and flight speed is on the order of 40 mph, significantly faster than the average PPC.
The big 656 sq. ft. chute was stable enough in flight, although slow and ponderous. Turns were slow and required significant effort at the controls. All this is to be expected from so much parawing area. Even with the big wing, the machine had a very steady feel with little propensity to "bounce" or rock in spite of the big wing. The 520 sq. ft. wing was very typical of most of the other wings of that size that I have flown. The notable difference being the apparent rock steady flight characteristics of this machine. I verified the difference by flying another make of machine minutes after flying a Para-Ski and the difference in stability was striking. The six-point flying cable suspension system and full-length rudder are probably responsible for this.
The most striking machine was the 420 sq. ft. equipped unit. This chute combined with the 75 hp Rotax 618 made for a hot ship by usual PPC standards. It felt very "airplane like" which made me feel right at home with my GA experience in light airplanes. This combination might be scary for newbies, but experienced PPC or GA pilot should find it an exciting ride. It was my favorite Para-Ski configuration of the three. Because of the high cruising speed, approach glide slope under partial power was much like that in an airplane. Although a bit "hot" (i.e. fast) on landing compared to other PPC’s, control was never in doubt and the machine was very easy to keep lined up. With a reasonable power setting, there was sufficient flare available for a smooth, if somewhat fast, landing. The four wheel, fully independent suspension and two wheel steering made these "hot" landings a none event.
If you are looking for an unusual powered parachute ride and the higher price doesn't scare you, this is the machine for you.
Ignazito lives in Charleston, Illinois. He is a registered mechanical
engineer in Illinois and a licensed private pilot with single engine
rating. He received his BFI for powered parachutes last fall and began
instructing then. He will continue instructing with a Buckeye dealer in
central Illinois next spring.
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