Full Lotus Floats

How do I know what size float I need?

To calculate the model Full Lotus float required, take the total displacement of the float system (i.e. FL 1260 is the displacement of one float, x 2 for dual floats = 2520 lbs of displacement) and divide by 2. (ie 2520 divided by 2 = 1260 lbs.) That will give you the maximum gross weight that the float system will support. However, we prefer to see you better floated. To calculate the displacement you require, take the maximum gross weight of the aircraft and multiply times two. If your aircraft has a gross weight of 1200 lbs (545 kg), you need 2400 lbs (1090 kg) of float displacement. IE. - a pair of our FL 1220 or FL 1260 floats. To have an extra margin of safety, we like to recommend multiplying your gross weight by 2.4 instead of 2. You pay a very small weight penalty with an inflatable float but the extra flotation really is appreciated in high winds or rough water.

What sizes does Full Lotus make?

Dual float systems are offered in displacements of 1220, 1260, 1650, 2150, 2250 and 2600 lbs.

What colours do they come in?

Colours available are yellow, blue and grey - no price difference based on colour.

Does Full Lotus have rudder kits?

Yes. Full Lotus offers a rudder kit, dual for large floats, and single for small systems.

I'm having problems getting on the step and lifting off the water. Why?

If you are about to install your floats, or perhaps you already have, give consideration to the following points.

It is VERY important where the Centre of Gravity ( C of G) of the aircraft (loaded to full gross) is with respect to the float; specifically with relation to the step. (Note - the best way to determine where the step is, since it's a bit hidden away under the float, is to take a length of wood such as a 2"x4" and place it flush to the back of both steps bridging the two floats).

For locating C of G relative to the float, some aircraft manufacturers will tell you that the step should be a given distance from a fixed point on the aircraft such as the main gear. This is fine for initial positioning and when you first fly the aircraft it may be prove to be spot on (lucky you). However, even with the same aircraft type, the actual C of G will vary somewhat from aircraft to aircraft so you should determine the ACTUAL C of G of your machine and then measure from this point on the aircraft to the step.

Measure with a plumb bob with the aircraft level. Generally, the C of G of the aircraft should be 4-8" (10-20 cm) ahead of the step depending on the size of float. (See Full Lotus operator's manual.)When you first fly the aircraft at full gross weight, given adequate power and thrust, the aircraft should move onto the step (planing) fairly quickly (5-6 seconds typically).

Excessive control stick movement should not be needed.

IF LOTS OF FORWARD CONTROL STICK OR YOKE IS REQUIRED, this means that the aircraft needs to move forward on the float. Move in 1" (2.5 cm) increments until no forward stick (neutral) or minimal forward stick gets the aircraft onto the step quickly. When you have moved the aircraft forward on the float, fly it first solo making sure that there is adequate forward buoyancy at this new position. Then do the same test at gross weight.

IF LOTS OF AFT STICK IS REQUIRED ONCE ON THE STEP, this likely means the aircraft is too far forward on the floats. Move the aircraft back in 1" 2.5 cm) increments until only slight back stick is required. Also read section following re porpoising.

Given that the floats are at proper pressure, porpoising can be caused by either lack of lift from insufficient angle of attack of the wing or two much angle of attack. Adjust your rigging to vary the angle of the wing (in 1/2 degree increments) until the tendency to porpoise is eliminated or greatly reduced. This change in wing angle should make your aircraft more willing to fly off the water, i.e. - it should reduce your take off time.If too much back stick is required after getting on the step, this can be caused by insufficient angle of attack or improper C of G positioning relative to the float (see C of G section). Always experiment first with C of G before changing angle of attack.

There is an old adage that a seaplane can never have enough power. Given the power that you do have, you want to ascertain that you are converting that power into thrust as efficiently as possible.In this regard, we recommend you perform a thrust test. This will tell you if you have adequate poop to get good float performance. Record the thrust number in your aircraft log book. This number is valuable baseline data should your aircraft's performance change in the future, i.e. - you can compare back.The best place to do this test is in the water (no wind, no water current). Run a rope from a secure point (e.g. - the hard points where the struts attach) and back to the tail. Lash the rope up to the tail making sure the tension in the rope is ALL taken up by the forward attach points. Do not attach the rope lower down, for e.g. to the floats themselves, since you will not get an accurate reading. (You will be below the thrust line.)Use a rented crane scale (like a big fish scale) to meas ure thrust. You may wish to check the scale's accuracy first against a known standard. If the scale only goes up to 250-300 lbs (114-136 kg), use a pulley to halve the load to the scale and then multiply your reading by two.A Rotax 582 with a 3 blade prop should pull 375 lbs (170 kg) or better. A Lycoming 0-320 with a medium pitch prop should pull 510 lbs (230 kg) or better.

Check to ensure that the thrust line meets the aircraft manufacturer's specifications.

If your floats are pigeon toed or splayed out you will be paying a performance penalty. You will also notice you are the recipient of rude jokes. To correct both situations, get parallel. Also make sure those parallel floats are also perfectly parallel to the longitudinal axis of the aircraft.

Check to make sure all bladder compartments have the correct air pressure.

Check that the elevator travel is correct with reference to the manufacturer's data in the aircraft manual. This may need to be adjusted.

Check the bottom of the step to see that it is functioning properly. With the plane out of the water, use a straight edge aligned lengthwise on the hull cap in the centre of the high speed area of the hull cap (where the stiffener board is), to make sure the bottom is absolutely flat. The step should not be concave at all. If it is, you may have a cracked or warped stiffener board. There should also not be a "lip" at the back of the step. It should be a sharp (distinct) 90 degree corner.

Can you use Full Lotus floats on snow?

Yes. Full Lotus floats work better than skis on snow. Their wider footprint allows for landing in softer snow than skis. They are also much safer than skis when landing on frozen lakes. If the ice breaks, a Full Lotus equipped aircraft will float.

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