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Peter Grey
Posts: 1488
Joined: Sun Dec 11, 2005 5:37 pm
Location: Prescott Valley, AZ (PRC)

Yet more flying fun from F57.

Fri Mar 20, 2009 5:37 pm

Hey guys, well I had another fun trip I figured I would tell you guys about.

One of my personal goals in aviation is to always be learning new stuff. With this in mind I went down to the Tampa area over Spring break to learn how to fly seaplanes. We have a lot of virtual seaplane pilots so I figure I would describe the training process.

I went down to Browns seaplane base in Winter Haven, FL (F57) which is located next to (I mean literally next to) KGIF.

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The process starts well in advance with study materials, specifically a 25 page document covering all the bases on what is to be covered. The plane of choice is the venerable J-3 Cub on floats. The only new equipment other then the floats is the water rudders (which are exactly what they sound like, they can go up or down as needed)

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The airplane I flew the entire time. The cockpit is very sparce and is blocked by the CFI anyway.

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Water rudder handle, thats the up position, for down take it off the hook and put it on the floor.

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Throttle, the water rudder handle is just at the bottom of the picture.

Transitioning to seaplanes really only requires one to relearn ground operations, specifically taxiing, takeoffs, and landings.

There are two ways to move a seaplane on the water, sail it (without power) or use power and water taxi.

The most important thing is, with the water rudder up the seaplane will always weathervane into the wind (it will with them down, but not as easily). No matter what you are doing this is true. Also full aft stick is always used (except when established on the step) when on water.

Seaplanes will sail just like a sailboat (the down alieron serves as a sail, and the air rudder which serves as, well a rudder) except in reverse (tail first). Alieron and rudder are used to turn.

With power there are 3 types of taxiing, the first and most common is the idle taxi (Exactly what it sounds like) the water rudders are used to turn.

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Airplane during an idle taxi.

In the event that wind is to strong to turn downwind (remember weathervaning), a "plow turn" is used, the aerodnamics are a little complex, but basically you shift the water CG back with power and let the seaplane reverse weathervane. This is done by applying full power then reducing to a set RPM (varies by plane), and applying full rudder in the turn with opposite alieron (wind correction), this forces the plane nose up, pushing the water CG back allowing the plane to turn (in theory, this wont work in high winds). Water rudders are also down for this manuver (this and the idle taxi are the only times they are used)

The third type is the high speed taxi, known as "step taxiing". The step is the break in the floats, it allows for a small part of float to support the weight of the plane (water generated lift) without the added drag of the back section. Entering the step (which is also how we start a takeoff), requires full power this inducses a strong nose up moment which is allowed. Several seconds later a second slower nose up occurs (caused by the front of the float lifting out of the water), you slowly nose over and are now on the step, power is reduced to a set RPM (dependent on wind direction).

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Video of a step taxi done by my CFI into the dock. This is around 30 mph.

As brakes dont exist on a seaplane the seaplane is slowed to a stop (minus current effects) by idle power and full aft stick, this is VERY effective.

From step taxiing a normal takeoff is done by leaving full power when on the step, the plane is not rotated and naturally flies off the water (in the J3 at EXACTLY 40 mph).

There are three more types of takeoffs, the first is the rough water takeoff (similar to a soft field T/O in a land plane). This is done by holding a higher pitch on the step (~5 degrees more) and getting airborne at the lowest speed. Once airborne you level off in ground effect till safe flying speed.

The second is the glassy water takeoff. Glassy water (absolutely no wind) is very hazardous due to the water causing more drag (this is complicated), and an inability to judge height (whos ever run into a very clean glass mirror). The goal in this takeoff is to get one float up as soon as possible to reduce drag by 50%. This takeoff starts like a normal takeoff until on the step. At this point left alieron is used to lift the right float up. Meanwhile right rudder is used to hold heading (imagine a sideslip on the water). Once the left float is off the stick is neutalized resulting in a liftoff of the right float soon after.

Finally we have the confined area takeoff (similar to the short field). Its impossible to do a static runup in a seaplane, however direction of takeoff doesnt matter within limits. So the goal here is to do a circular takeoff. The manuver starts with a left crosswind, once power is added the plane is put into a slow left turn on the water, once on the step (and still turning) the right float will lift, once this happens a left bank is established, soon after the left flaot lifts and the plane is airborne in a left turn. The turn is kept over the lake till obstacles are cleared.

Ok, still with me, finally we have landings. The trick with landing a seaplane is that you can really do whatever you like. There is no specific direction you must land and as a result you generally land with a direct headwind or with a slight crosswind for a more convient heading on touchdown (like pointed at your docking ramp).

Patterns in the J3 were done at 500 feet and 2300 RPM (around 65 mph), base and final were tight and all the landings are done power off (at least until the flare).

A normal landing works almost identically to a landplane. Flare nose high and touch down. Once down still full aft for braking (time to a stop is only 2-3 seconds). Because of the short distances there is no such thing as a confined area landing, it isnt needed.

A rough landing works like a soft field in a land plane. Everything is normal till the flare where power is added (1400 for the J3). The nose is kept high to allow for a softer touchdown, once on the ground full aft is done.

Finally is the glassy water landing. The problem here is that you dont know how high off the ground you are (making flaring impossible). So this is done by picking a visual reference as close to the water as possible (lilly pads are great for this). You aim in the power off glide just before that point, level off around 10 feet, set a flat landing pitch and add power to 1700, all before that point. Once past that point everything is held until the firm landing occurs. Once touchdown happens, power out and stick full aft.

Ok, thats the theory, so how does this all work. Brown advertises a 5 hour course + checkride in the cub.

The course starts with a 1.5 hour ground session that covers the above and some J-3 specific data. A fun fact is that adding floats to the J-3 makes the plane go 2 mph FASTER!

The course gets down to the point quickly. The J-3 is a very simple plane to operate, and has a total of 10 switches/levers/controls. They are:

1. Stick
2. Rudder
3. Throttle
4. Magnetos
5. Fuel shutoff valve
6. Engine primer
7. Trim
8. Water Rudder
9. Carb Heat
10. Intercom switch

There is no electrical system and the plane is hand propped to start. The door is left open usually, and the student sits in the back (the solo position). The plane is a tight fit. I had to jam my legs in to get to the rudders, it was not comfortable and I'm still a little sore 2 days later.

The first flight is planned for 2 hours. After meeting my insturctor we got the plane in the water, hopped in (not easy on water when 6' 3"), and started up. We kept with a simple idle taxi across the lake to a downwind position, let the plane weathervane and did a normal takeoff. Just as advertised the plane flies itself off the water.

Due to KGIF being 500 feet from the shore of the lake, no patterns ops are done at F57 (which having no radios in the cubs the local appreciate Id imagine, takes traffic avoidance and visual scanning to a new level). The final approach to the 2 main runways goes over the lake. Planes will be over the lake from 200-1000 feet and cut across the lake downwind and final. Several landings at F57 were changed last second to avoid a land plane.

Put "Lake Jessie, Winter Haven, Polk, Florida 33881" into google maps to see how close they are. Lake Jessie is F57. The base is at the NE corner near runway 11.

Ok airborne we go up to 1000' (the highest we will go the entire time) and do some manuvers to get use to the plane, steep turns, and power off stalls. You can tell the plane is about to stall as the open door starts to close.

With that done we picked a nearby lake (there are TONS), and did a normal landing. Basically over the 2 hours we did 20 landings on different lakes using different styles of takeoffs and landings. By the end of the first flight every manuver had been introduced and practiced. The only susprise was a simulated engine failure, the procedure is just to do a 60 mph best drop (its a brick with floats on it), and flare like a normal landing.

After the first flight we had lunch, then a second 1.5 hour flight. The only susprise on this flight was the oil cap popping off at 300 feet causing white smoke to pour out of the engine and necessitating a quick landing to fix this. After the fix we tried again, and same result....

After fixing it again we went back to base to get a new cap. This would be the only issue the entire time. The second flight went just like the first but with more complicated lakes to work with (the hardest part of any seaplane landing is figuring out the lake).

That was it for the day. The plan for day 2 was a 1.5 hour flight followed immeditely by the checkride. The third flight was a repeat of the second with new lakes and no help from the CFI.

Checkride time, checkrides are done by an 2 FAA DPE's, the owner and his brother. After a quick oral session, we went out to the plane. By this point winds were around 10 knots, with the max allowed of 15 knots this was getting up there for a seaplane (remember weather vaning). Also the J-3 can only handle 18 inch waves. The checkride was simple, due to winds only normal takeoffs were done, followed by a normal landing, a glassy water landing, and an engine failure. After that it was back to F57 for a normal landing to a step taxi to the dock. That was it, a .8 and a new certificate in the pocket.

Honestly its the most fun Ive had in an airplane in a while. It was great. Hopefully this helps you'll understand our favorite non land plane.
Peter Grey
Instructor - ZLA
N31ER
"Nice Landing, Contact ground point 5"

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Wayne Conrad
Posts: 1494
Joined: Thu Dec 14, 2006 11:24 am
Location: Phoenix, Aridzona

Sat Mar 21, 2009 3:37 pm

This really should be in Playboy. It's just porn. Pure porn.

You slut.

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