Guest Editorial: Things To Do With Your Aeronca – Guest Editorial – Submitted by Robert Kittine – As I gaze at the cover of the October 2013 Aeronca Club Magazine, I again realize how dumb I was to sell my restored Chief on EDO Straight Floats. Determined to get back on (and off) the water, I recently purchased a set of EDO 92-1400 Floats with Chief rigging as well as a set of Federal 1500 Skis. As great a feeling it is to blast down the runway at 40 or 50 mph and take to the air to later return landing gently (or with a few little bounces) on a manicured lawn or even some potholed asphalt, sliding around on the water or snow is another added dimension and level of enjoyment to add to our favorite airplanes. Now I just need another Chief.
This gave me an idea for a series of articles including Float and Ski Operations as well as Aeroncas on Floats, Aeroncas on Skis, Refurbishing Floats and Refurbishing Skis, all projects that I am now undertaking. As this is too much for a single article, let’s start with what is involved with getting your Aeronca legally on floats.
Since before the Second World War, Aeronca Type Certificates have allowed for Straight Floats in various forms on many Aeronca Models. Straight Floats, unlike Amphibious Floats, that allow landing and taking off on solid ground, are meant to be used in the water only and to date, no amphibious floats have ever been Type Certified for installation on those airplanes.
To install floats on an airplane other than by the information included in the Type Certificate, one must either find floats where the manufacturer has applied for – and received – an STC for installation of their floats, or one must install and get a field approval, which in today’s day and age seems to be near impossible in this country. It is somewhat easier if you have an Experimental category airplane or if you are in Canada, especially operating under the 51% home build exemption. But for this discussion, lets stick with what can typically be done in the United States.
EDO, is the only float company that has provided a line of floats accepted via the Type Certificate for Aeronca Chiefs (Post and Pre-War) as well as Champs and Sedans. Unfortunately EDO is no longer in business and although Kenmore Air has purchased the rights to the type certificates and drawing, they only fully support the floats starting with the 2,200 series.
Although PK 1500 floats can be found with an STC for installation on Champs, they are hard to find and especially hard to find with the appropriate rigging. Companies like Baumann, now out of business, Wipaire, Mead, Full Lotus and others have developed floats with the intention of certification on Aeroncas, those certificates never materialized. So, our choices are basically EDO 60-1320s, 92-1400s or 89-2000s. Those numbers represent the design flotation criteria, I.E. 1320 should float a plane at a Maximum Gross Weight of 1320 pounds, but are designed to be able to float at least 10% over that weight.
Good time to note that for those of us currently flying LSA, the 1320 Max Gross Weight stipulated for aircraft is for those on wheels and for float flying that weight is increased to 1,430, an added 110 pounds. There are planes that qualify as LSA on floats, but not on wheels, but not any of our Aeroncas, with the exception of the 11CC Chief, which does not qualify on Wheels, but does on straight floats.
Aeronca Float planes were supplied from the factory with some modifications as well as an “S” Designation. Hence the S7AC was the Seaplane Version of the 7AC. As a base line the following float combinations are covered by the type certificate:
- C-3K – And other early Aeroncas – EDO D-1070 (Try finding some of these)
- 65CA – PreWar Chiefs – EDO 60-1320
- 11AC, BC and CC – EDO 90-1400
- 7AC Champ – EDO 60-1320 or EDO 90-1400 (See the notes on this in the section on which plane for you?)
- 7BC – 7EC Champ – EDO 90-1400 (though the 7EC does not qualify as LSA on or off floats)
- 15AC Sedan – EDO 89-2000, which also does not qualify as LSA for a number of reasons.
So, what do you need to put your Aeronca on Floats?
- The appropriate floats as listed above.
- Spreader Bars for the floats, which are the same for any given model regardless of the aircraft they are going on.
- Struts, usually 6 to support the airframe on top of the floats. Due to the angles involved, these are specific to each model aircraft. I.E. Struts that work for all “7” Series, will not work for all “11” Series Aircraft.
- Fuselage fittings to attach the rear struts to the fuselage.
- Front Fittings to attach the front struts to the landing gear attachment points.
- Additional Vertical Fins, either one single below the tail section or two small vertical fins attached to the horizontal stabilizer.
- Connecting wires to interconnect the water rudder(s) (these floats are available with one or two water rudders) as well as for retraction of the rudders. Also cross bracing wires.
In addition to the floats and rigging a few other things are suggested:
- A paddle;
- A hand bilge pump, to pump out the multiple float chambers;
- Addition lines for docking;
- A small anchor;
- Inflatable Vests for all Crew members and passengers;
How about the plane itself:
- Best to make your plane as light as possible. Seems like most of our Aeroncas have gained weight with age. (Sounds like me) Get rid of unneeded instruments, heavier seats and cushions, carpeting or anything else that you can legally remove to get your plane closer to what it would have weighed leaving the factory as an “S” model seaplane.
- Hand propping on floats can be done and is relatively easy from your home dock where you might have set up a tether system to hold the plane in place until the engine is started and you are inside the cabin. This does not work when you are stopped in the middle of a body of water to throw out a fishing line and now ready to depart. A light weight starter and a battery is more of a necessity than a luxury that it might be considered when you plane is on wheels. It does not take much wind to move the plane around on floats even with the engine shut down, so hand propping without being tied down is a real challenge.
- A seaplane door will go a long way to help if you must hand prop either because you do not have a starter or in case your battery is dead. I have a Seaplane Door on my 7CCM made by a modification to the stock Champ door. Happy to supply the information, pictures and a copy of the 337 and Field Approval to anyone that may want it.
- Although an 11AC with an A-65 can legally be put on EDO 90-1400 floats, getting you, a passenger and some fuel into the air will be a challenge especially on a no wind day. A C-85 or higher HP engine will help to make your float plane more user friendly.
Which plane is best for you?
If you already own an Aeronca and your budget does not allow for one on Wheels and one on Floats / Skis, then that is the model that probably will work best for you. If you are deciding on which model to purchase to put on floats, then you first consideration is if you need the final aircraft to qualify as LSA or not. Pre-War Aeroncas and all “7” Series through the 7DC as well as all “11” Series, qualify as LSA on Straight Floats. “7” series starting with the 7EC and all Sedans, do not qualify for LSA status, so there are your limitations for staying LSA.
So assuming that you want to stay within the confines of LSA, then what do you want to do with the plane once it is on floats. If you intend to fly by yourself or with a lightweight companion, then there is not a lot of difference between the “7” Series and the “11” Series, but if you want two adult males to be able to operate either in a training environment, or just for having fun, then you might want to consider the Pre-War or Post War Chief as the best aircraft for your needs. The reason for this is that as you add weight, it stays pretty much over the center of gravity in a Side-By-Side aircraft, while when you add weight to the back seat of a tandem seat aircraft, the shift of the CG rearward can greatly impede the ability to get “On The Step” especially in a light or no wind condition.
If you and your proposed companions can fit in a Pre-War Chief, say a 65CA, then you can find a great combination of that aircraft installed on a set of EDO 60-1320s, which are allowed by the Type Certificate. In talking to J.J. Frey, the past General Manager or EDO and Bill Pancake, who almost every Aeronca owner knows or has heard of, this is one of the best light float planes available. The design of the 1320s apparently was very superior to the design of the 1400s, but due to the cost to manufacture took a back seat to the 1400s. The installation of a C-85, C-90, 0-200 or 0-235 will help considerably.
If you have a Post War Chief or a “7” Series other than a 7AC, then you have a different situation. All “11” Series Aeroncas require EDO 92-1400s by the type certificate and I do not know of any STCs available that change that. Unless you have a very light 11AC, a C-65 and 1400 floats is not going to be a great performer, but if you add a C-85 or higher HP engine, you will enjoy flying your Chief with 2 on board and some fuel at least in the nose tank.
A 7AC with a 65 HP engine allows EDO 60-1320s by the type certificate, but unless you have a very light airplane, you may not be impressed with the performance. Add a bigger engine and convert to a BC, CC or DC and you will need the 1400s, which unless you have a light airplane may present performance problems, but there is an alternative.
Bruce Dunham and his father before him trained hundreds or seaplane pilots in 7CCMs floated on EDO 60-1320s based on an STC that they hold. This STC is still available and specifically allows 7CCMs with the C-90-8 Engine to be used with EDO 1320s. Any other engine may require a field approval, but the “-8” with no accessory case of the “-12” and a lightened aircraft, is a winning combination for a seaplane primary trainer.
My favorite and the one gracing the cover of the October issue is an 11AC Chief, with a C-85 on EDO 1400s. In my case, a Stroked C-85-12 as converted by the Don’s Dream Machine 0-200 Stroker STC.
If LSA is not a requirement, then I would stay away from a 7EC if possible as that aircraft has a lot of added weight while still only having a C-90-12, which will not be a stellar performer. For non-LSA a Sedan on EDO 2000s will give you great performance with 2 adult males on board, plenty of fuel and available weight for some fishing / and or camping equipment or for a couple of light weight children.
For two people max 7GC or 7GCBC with a 150 – 180 HP engine on EDO 2000s or even 2200s will fit the bill. Pick your mission, pick your plane and pick your float set up. In the next addition, we will talk about flying what you have built.
This article first appeared in 2013 in the Aeronca Club Magazine. It is published here with permission of its author.