SKIMMER OPERATION |
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The C-1 Skimmer came equipped with a Lycoming 0-320 engine of 150 horsepower, and room on board for 3 souls and 240 pounds of fuel. Needless to say, if one exceeds the load limits, it performs very poorly, especially with a “tired” engine on a hot day. However, if one keeps the plane light, it is a spritely performer, especially with the wing extensions. Because of its configuration of being a “pusher” and a boat-hulled amphibian, it has certain characteristics unlike any other plane. None of these are dangerous as long as one is aware of them. The first, and most important, is the fact that when power is applied the nose is pushed down by the high thrust line and conversely, when power is reduced, the nose rises, a directly opposite reaction to a standard Piper or Cessna. It takes but a few moments to get used to this phenomena and compensating for it with up or down elevator. It can be used to your advantage. Secondly, because it is a pusher, one cannot “hang it on the prop” as can be done with front-mounted engine like the Piper or Cessna. One must convert forward speed into lift and that can only be done by lowering the nose to a level attitude, especially when near the ground or water. Thirdly, because of its boat-hull, it cannot be flown like a pontoon equipped floatplane. In water operation you must be either on the step in a flat attitude, with power, or in displacement with no power. Alighting on water is done in two ways: A step landing (where the step on the bottom of the hull touches first) or a full stall landing (where the tail touches first, no power, elevator full up). Anything in between usually results in a skip out of the water due to the nose-up attitude and excess speed. Recovery from this attitude is most important with a “pusher” flying boat. Generally it is best to convert a skip into a full stall landing, since flying speed has deteriorated considerably. Most important with an amphibian is being aware of the placement of the landing gear. Landing with the wheels down on water is not permitted and very costly and dangerous. It is imperative that you announce aloud at each approach to landing, “This is a water landing, the wheels are up” or “This is a land landing, the wheels are down”. There are indicators in the cockpit to show where the wheels are, but in the Skimmer it is possible to see the main gear by looking out the window and the nose wheel by looking into a mirror mounted on the left float. There is no excuse for landing with the wheels in the wrong position. They should be checked several times prior to landing. The Skimmer is equipped with hydraulically operated landing gear and flaps. It is activated by an electric pump with a pressure switch to turn the pump on and off and an accumulator to pre-load the system for fast gear retraction, plus an emergency hand pump should the electric one fail. The selectors are shaped like what they are, a wheel and a flap, and must be moved out of a detent to select the next position. The indicator lights are wired in series with switches on each gear, so all must be in the proper position for the indicators to operate. Flaps are either in the up or down position and are “slotted”, low speed-high lift flaps. Best rates of climb speeds must be adhered to for best performance. The long gear legs, when extended, create a lot of drag and attention must be paid to maintaining airspeed when power is reduced. Conversely, one may dive the aircraft in a disconcerting nose-down attitude without worrying about reaching the never-exceed speed. Gear and flap operation speed is 125 miles per hour. Longitudinal trim is controlled by knurled wheel below the pilots right hand forward of the front seat and controls either tabs on the elevator (early C-1s) or tension on a spring connected to the elevator (later C-1s). Porpoising on the water: this subject blown way out of proportion in most circles. Yes, it will porpoise if the elevator is not controlled properly. The method of stopping a porpoise is to use up elevator until it stops. It will. Immediately. In fact, with reduced power, on the step, one may hold full down elevator with no porpoise occuring. As in any airplane capable of landing on the water, never try to “put” the airplane on the water. Set
up the correct attitude and wait for it to land itself. The same rule applies for takeoff. The C-1 Skimmer, as well as the C-2 Skimmer and Lake Amphibians are
comfortable and safe, easy planes to fly, providing certain techniques
are followed. |
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The C-2 Skimmer has the same basic airframe as the C-1 with a few changes. It sports a Lycoming 0-360 and a metal propellor mounted on a slightly different pylon from the C-1. The interior now has two moveable front seats and a bench seat behind, and the control wheel comes out of the instrument panel rather than up through the floor between the pilots legs, as in the C-1. The gross weight was increased by 200 pounds to 2350. It has small nose gear doors partially enclosing the nose gear when retracted. Longitudinal trim is now accomplished by two small elevator like tabs mounted at the outboard ends of the horizontal stabilizer. They are operated hydraulically by a selector set between the two front seats and from the existing hydraulic system. As mentioned in the C-1 operation, weight is critical to performance. The extra horsepower makes a huge difference, but the extra seat allows more room for overloading. We also now have a small baggage area located behind the rear seat. The nose gear of both the C-1 and C-2 Skimmer is not directly steerable but castering, with a damper installed to eliminate “shimmy”. One must get the Skimmer moving first and then a tap on the brake casters the wheel for the turn. Returning to straight ahead is done exactly the same with the other brake. This allows for very tight turns. The aircraft is super stable on the ground due to its low profile and 12 foot wide stance. All three wheels use hydraulic “oleos” to absorb landing shock. Engine controls on both models are mounted on the ceiling between the pilots with the throttle hanging between the hinged entry hatches. One feels comfortable with the arrangement very quickly. The powerful rudder of the Skimmer allows one to make a tight turn in the air with rudder alone, and the dihedral of the wings allows one to take their feet off the pedals with the aircraft remaining in the turn, untouched. A huge water rudder hangs in the base of the “air” rudder and is extended and retracted by a lever on the left side panel in the cockpit, and controlled by the rudder pedals. It is very effective for turning in the water, as is the large “air” rudder with a slight increase in power. It is unusual to have to “sail” the Skimmer even in a strong wind due to its ability to turn and the stability provided by the wing floats. Needless to say, all turns on the water, fast or slow, should be made with the rudder. The Skimmers live in two different worlds; that of boats and planes. It is not uncommon to go tearing around the body of water at 30 miles per hour making tight turns or planing downwind on the step and making a 180 degree turn into the wind for takeoff. The most common mistake pilots make is letting the Skimmer get too close to flying speed for maneuvering. Keep it slow when a boat and fast when an airplane. Or, keep the weight on the hull when a boat and on the wings for flying. An excellent way to learn the proper attitude for a step landing on the water is to stand on the ramp at the airport and look at the Skimmer. Now, imagine it with the wheels retracted. Note that the step is the lowest part of the aircraft, the bottom sloping up to the nose and the tail. This is the correct attitude. Sit in the aircraft and imagine that the asphalt is water and note how high you are sitting above the surface. This is exactly what it is going to be like just before your water landing. Bear in mind that most pilots overfly the Skimmer when they should be setting up an attitude for what they want the plane to do and wait for it to happen. A water takeoff is an example. Trimmed properly, a Skimmer will get up onto the step and plane without any assistance from the pilot and lightly loaded, will takeoff. Climb, fly the pattern with rudder and trim use only, adjust the power and trim for the descent, level off inches over the water and wait for it to land itself. [John H. Staber 2003] |
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Updated: 2003-10-09Copyright © 2003 John H. Staber & Steinar SaevdalE-mail: Steinar Saevdal
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