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 It has been a love that has
become an addiction - and an addiction that has nearly killed me
twice. Mind you so has flying, but those are stories for
another time.
Now remember just about any
ultralight can be equipped with floats, or for that matter can
be made amphibious. But there are a number of things that you
must consider when adding floats to an ultralight.
These deal with the floats, the
plane, pilot and the "air(water)field".
The Plane:
There are basically two kinds of
float planes - ones that are built to be float planes and those that have been
adapted to handle floats and or amphibious gear.
These also can be broken down into a center hull or float like
the Buccaneer Amphibian or the Lotus Mono Hull and the two float
system.
The Center Hull or Mono-float systems - These craft land and take off on a center float, with two
sponsors out on the wings for support in cross wind
conditions. On the "Mono-Float' system the pilot sits in his plane but
above the float, and when on amphib gear he is
"really" above the float. When landing this takes a
bit of getting use to. When you land on water the plane
"floats" on the center hull and can tip one way
or the other depending on the wind. When landing on land the
pilot has to get accustomed to the extra height required by the
landing gear to allow the float to clear the ground.
While in the
"amphibian" craft like the Buccaneer the pilot sits
inside the "float" and literally lands with "seat
of his pants" touching the water.
 Both aircraft present
problems when trying to dock, for fuel, or to get in and out of
the plane.
With the sponsors out on the wing it is hard to get close to anything, and
unlike dual floats when you try to exit the craft you do not
have anything to step out onto. Thus these craft really need an
area where you can drive them in an out of the water. Experience
has shown that the "amphibian" style are not as suited for lakes with high wind and rough water.
For "TRIKE" lovers
there is the "flying boat" a unique unit that is now
available from a couple of different manufacturers. In this
application a boat, similar
to what most people know as a "Kodiak boat' is attached to
a Trike airframe. Giving you the best of both worlds.
The next type of plane is the
land plane which has been adapted to handle floats
 - that is the two float
system. For ultralights there are a couple of different styles
of floats on the market, from several manufactures. We currently
have available to us the Full Lotus float
system, the Puddle Jumper fiber glass floats, and aluminum
floats available from Zenair, Murphy and Aquafloat.
The Full Lotus two float system for ultralight is available in
two sizes to fit ultralight aircraft weights up to
1260 lbs. Advantages of this system are they are strong,
durable, easy to repair, light weight, easy to ship, are already
built, and can be easily mounted on any ultralight. They are
available as straight floats or amphibs.
Problems: Over the years Full Lotus has updated or revised their
floats on several occasions. In 1999 they put out an update
which changed the way the upper and lower sections of their
float system are held together. This update is available to ALL Full
Lotus owners free of charge.
For more information click
here!
The main problems reported by
owners, of Full Lotus floats is "ruptured or leaky bladders." The ruptured
airbags are usually a result of "stall landings," and
or improper inflation. 
The loss of air in the bladders are usually a result of improper inflation which
allows the bladders to move inside the float causing them to
"pinch" and leak.
WATER IN THE BLADDERS is another
reported problem. I found it hard to believe that water
could enter a bladder, when there was no loss of air, or signs
of leaking.
Apparently there are a number of ways this can
happen.
*One the air used to fill the bladders from a compressor
contains water.
*When air is heated and cooled water forms.
Picture
a float sitting on water on a cool summer night, then picture the same
float at mid day and 90 degrees F.
*Another way according to
informed sources is "osmosis". Now I am not going to
try to explain this one you'll have to look it up and draw your
own conclusion.
While teaching on a Murphy Rebel equipped with Full Lotus 1650 floats, I removed over 15 gallons of water from the rear bladders! A gallon of water weighs approximately 8 lbs! It really got my attention when it moved to the rear of the floats during climb out.
The next type of
 float
is the fiber glass float. Puddle Jumper is one manufacturer and
their floats can be found around the country on Challengers,
Rans, Titan aircraft etc. The floats come in about the same
weight as the Full Lotus (roughly 150 lbs). They come prebuilt,
ready for installation, and are available in also with amphib
gear. These floats are favoured on some aircraft because of
their lower drag, and I can say that on planes like the
Challenger they do out perform the Full Lotus system for getting
out the water.
Problems: The main problems
reported from pilots using this system are, the strength and
durability of the float - with the floats report ably cracking at the step and where the two float halves are joined
together. This normally results in an overturned plane. Another
reported problem on the older systems using the amphib set up
was with sticking real wheels and failed nose wheel supports.
Click here for more info on Puddle
Jumper Floats.
The next type of float is the
aluminum float. Several manufac turers
offer kits, including Zenair, Murphy, and Aqua Float. Aluminum
floats were the main stay of the aircraft industry and have been
around since the inception of flying. For ultralights most have
to built from kits that take between 200 and 300 hours to build.
They are light, very aerodynamic, and because they are kit
built, are priced within the reach of most pilots.
Problems: Most problems reported
deal with the "durability" of the float, and with
constant leaking. Many pilots report getting pin holes in their
floats after beaching for short periods of time on sandy
beaches.
One way of helping to prevent "leaking" is to
"slosh" the inside of the floats with a rubber
sealant.
Click here for more information on Aluminum
Floats .
If you are flying on floats
ALWAYS check for water in the float and or bladder compartments.
On the Full Lotus system a check 3 or 4 times a year is
recommended. On fiberglass and aluminum floats check prior to
EVERY take off! Many pilots install small electric bilge pumps
like those used in boats. When mounted in the step area of the
float it allows easy draining of the float.
I believe a gallon of water weighs in at
about 8 lbs - two gallons moving to the tail of the float on
lift off can and has caused ultralights to crash and pilots to
be injured or killed.
For
plans for floats for ultralights click here.
Now I am not going to get into
mounting your floats. But you need to make sure of several
things ALL of which should be available from your manufacturer
or the float supplier.
It is important that your floats
mounting hardware is strong!!!! During take off and or
landing you can reach speeds close to 50 mph. When you consider
you plane can weigh in at 1200 lbs - that is a lot of stress on
everything. This would not be
a good time for mounting hardware to fail!
The position of the float
relative to the center of LIFT on the wing is critical, as is
the position of the floats relative to the C of G of the plane!
Another factor is the angle of incidence BETWEEN the floats and
the wing.
Floats mounted to far back will
cause the nose of the plane to push up and possibly stall, too
far forward and the plane will be nose heavy. If the angle is
wrong between the float and the wing you may not be able to
rotate, or produce excessive drag.
Your Plane:
Okay you have decided what kind of float you want to go
with - now lets look at a your plane. Let's say you take
an average float system set up you will be adding about 150 lbs
to your plane. In most cases you will also add extra fuel
capacity, and possibly an electric start and battery, if you
have every flown on floats you'll understand why! If not picture
yourself standing on a set of floats at the rear of an RX 550
Beaver pulling on a recoil rope, with a prop about 2 feet from
you as your plane starts moving forward when the engine starts.
You will also be flying during the summer months, which
generally come with hot humid days, while some Full Lotus
customers fly on floats all year round I wouldn't recommend it
on fiberglass or aluminum floats.
Imagine you have just increased
your body weight by 35%, none of this being MUSCLE just weight,
now try climbing a flight of stairs, on a 90 degree day with high
humidity! That is what you are asking your plane to do. So
BEFORE you decide to put floats on your plane think of what kind
of performance you get out of it as a land plane, when it is
loaded. If you get about 500 feet per minute climb and cruise at
65 mph - chop your climb rate in half and take about 10 mph off
your cruise at the same power setting.
In most cases more power is
recommended - BUT this also depends on whether your plane can take
the additional power and extra weight of a larger engine. The
only person that can tell you that is the AIRCRAFT manufacturer.
Another factor you MUST be aware of is your gross weight -
many ultralights could be OVER GROSS when equipped with
floats - do the math.
Propeller: Your propeller is
another thing you have to consider. If it does not have some
kind of leading edge protection on it - after one take off you
will be able to use it as a wall clock! A ground adjustable prop is a more worthwhile investment than a
fixed pitch prop . On floats you can dial it in better for take off -
and then redial it back when you switch back to wheels.
My preference is for composite
props like the IVOPROP
over wood propellers. I have found that wood props require more
maintenance, rot, varnish peels off, expand and contract -
which can effect the torque on your prop bolts. They also goes out of
balance more often.
The Pilot:
A pilot flying on floats needs to realize that there is a
difference in all fazes of the flight operation.
Preflight: A float plane is
harder to preflight - you can't get at things the way you can
on a land plane. BUT a thorough preflight IS required none the
less! AND that preflight MUST include the floats - inside and
out as well as the mounting hardware!
Boarding: NEVER ALLOW anyone to
board OR exit your plane when the engine is RUNNING. Instruct passengers
or crew on the proper way to enter and exit the craft PRIOR to
boarding. ESPECIALLY deal with the emergency exit procedures and
ensure adequate life jackets etc are on board and within reach
or INSTALLED on the occupants.
NOTE OF CAUTION: Personal experience has shown me that a
standard life jacket can pose problems when exiting an
overturned and submerging craft. The bulkiness and floatation
can hinder a smooth exit. WEARING the type of vest that you can
inflate once clear of the craft may be an option.
Starting the engine: Remember
when you start the engine YOU have NO brakes. So make sure NO
ONE or NO THING is in your path - remembering that the path is
about 35 fee wide! Consider the wind, speed, and direction
BEFORE you start your engine. If the engine starts and you move
out onto the lake and then it quits - where are you going to end
UP! PADDLES for both pilot and passenger are recommended! A tow rope is also handy - that way you can through it to a boat to
tow you in - to shore so someone can help - or you can jump into
the water and with the rope attached to the plane act as an
anchor to prevent it from going into the rocks etc.
Taxiing: While water rudders do
aid in steering your plane (most ultralights I have flown do not
have them) they are not as positive especially in a wind as when
you taxi on land.
When taxiing DOWNWIND be very
careful - especially on aircraft like the MX with a high wing
and tail. I have watched several times as pilot's have throttled
up while going downwind - and watched as the tail lifts up and the
craft somersaults forward.
When you have to turn cross wind
on the water try to make your initial turn into the wind
rather than with the wind pushing you. And use your ailerons to
keep the wing that is into the wind down! ( Practice in a large
vacant section of the lake - using short blasts from the
throttle to help compensate for the wind.) On amphibians like
the Buccaneer be careful turning - waves will fill your hull
with water. THIS WATER must be pumped out prior to take-off.
Again a small bilge pump running while you taxi will come in
handy.
Take Off: When considering how
much room you will need to take off and climb out. Visualize
what you would need for a normal take off on wheels. NOW at
least double it! Whether you know the lake or not - taxi the
full course up and back. Look for things like rocks, or other
obstacles, something like a log that might have drifted in. By
taxiing the complete length of your "runway" you do
one other thing - you have just checked for BOAT wakes. NOW
before you take off look to make sure NO boats have crossed your
"runway." Hitting the wake from a large cabin cruiser
at 45 mph - just as you are about to lift off will really get
your attention! You will lift off STALL and hit the water like a
rock!
When taking off - take off INTO
the wind - and remember that on calm glassy water, with little
or no wind it is MUCH harder and will take longer to break free
from the water.
Your next problem is that you
have now taxied your engine for probably 10 minutes it is cold!
You need to bring the temps up to operating temperature - hard
to do with no brakes. To do this bring you plane up on to the
step and taxi along a bit. Then apply your power slowly until
the plane lifts off. DO NOT use abrupt power inputs. This will
help prevent COLD
SEIZURE!
Flying: Some things you will
notice while flying on float vs. land is that your climb rate is
not as good. Thus you need to consider that boat house or 100 ft
tree at the end of the lake. I once stood helplessly on shore
while a friend took off on floats. He took too long to get
airborne, when he did he couldn't clear the bull rushes at the
end of the lake. It took us nearly 4 hours to pull him out.
BEFORE you take off mentally make an "abort" mark on
your "strip." This spot has to allow you to back down
on power and stop long before you are in trouble. With me that
would be about the halfway mark. Use something on the shoreline
for a reference point.
In most cases you will need to use
a higher throttle setting to maintain the cruise speed you are
accustomed to. This will usually mean a higher fuel burn so make
sure keep track of your fuel. Where you use to be able to fly
for 2 hours you may now only be able to fly for an hour and a
half.
Turns will probably feel a
little "mushy" - due to the added drag and extra
weight. REMEMBER that the addition of floats and the added
things that go with them WILL increase you stall speed AND cut
down on your glide ratio. Most float planes glide like a
rock!
Landing: Like taking off on
water landing also requires a couple of additional checks and
considerations. First when landing and taking off - try to take
off as close to shore as possible without causing danger to
those in the surrounding area. Try to take off and land while
someone is WATCHING. Take off and land where possible
within 50 feet of the shore and preferably with
fisherman in the area! Why - because when you sink he will see
you and hopefully come to your rescue.
Landing close to shore gives your
mind a perspective of where the water is - in the middle of the lake
your brain will find this hard to compute - because it has
nothing to refer to.
Use your circuit to look for
boaters, swimmers, obstructions, wave height, wind direction
etc. Especially look for boaters that MIGHT be getting ready to
head out. Someone getting ready to pull up a water skier for
example.
Another recommendation is to
OPEN or at least unlatch your doors where possible. When a plane
crashes into the water things have a tendency to bend. A bent
door frame or a sliding canopy guide rail can trap you inside, then prevent you from opening the
door or canopy.
If you have a
passenger instruct them once again on HOW to exit the plane
remembering that in all likely hood they will be upside down
with water rushing in and pushing against the doors. Your body weight
will be pressing against the seat belt. A sharp pocket knife is
something I now carry with me when float flying.
Of course water condition also
plays a part in accidents. Too calm and you CAN'T see the water.
Too rough and you risk float damage, and or upsetting. That is
another reason for landing close to shore and picking a calmer
section of the lake, even if it means a long taxi back to where
you want to go.
Remember there are only two
kinds of float plane pilots - those that have gotten wet and
those that are GOING to get wet. As you can probably guess from
the above I fit into the first category - several times.
U.B. Judge
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