New 100hp Amphibian Seaplane Homebuilt

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

Lee Schaumberg

Well-Known Member
Joined
Aug 28, 2003
Messages
215
Location
Northern Wisconsin
Hello
I don't have to fly LSA. May be you do. I am an instrument rated com pilot!
Because all I get is nonsense when I post I'll let every one mouth themselves.
 
Last edited:

Rhino

Well-Known Member
Joined
Apr 8, 2004
Messages
771
Location
SW Ohio
Hello.

You said you wanted an amphibian seaplane because "As the body ages it gets hard to get a 1st class, 2nd class, or 3rd class medical. The LSA only requires a driver's license." That's why I asked what I did, because you specified Sport Pilot as the criteria. It was just a curiosity question anyway. I haven't seen any indication of nonsense or 'mouthing' here.

I may stick with Sport Pilot. I don't know yet. But I still plan to equip my plane for night VFR, if for no other reason than I might want to sell it someday, and that would likely be attractive to a prospective buyer. I was just curious if you were thinking along the same lines, since you said you wanted the plane for Sport Pilot purposes.
 
Last edited:

orion

Well-Known Member
Joined
Mar 2, 2003
Messages
5,800
Location
Western Washington
Now, now, let's play nice. In following this discussion I also thought we were talking LSA, simply because of the 100 hp listed in the heading and the reference to the Mermaid, which is an LSA compliant airplane.

But I have to admit, unless the individual or potential customer specifies up front the performance specs he is working toward, I also from time to time nowadays make the assumption that he is looking for a lower end of the spectrum airplane or an LSA capable one, simply due to the recent prevalence of the subject matter.

Hello
Unfortunately I went to school to become a mechanical engineer not an aircraft designer. A well designed LSA amphibians seaplane set of plans could easily be sold. The cost of the plans could be 400 dollars. Total sales for 1000 plans would be 400,000 dollars. With sales like these all kinds of stuff could be done and it could be tax deductible.
Lee
It's a nice scenario but I'm afraid not a very realistic one. First off, I'm not sure that anyone in this industry has actually sold 1,000 plan sets in the last fifty years. I'd be rather doubtful if anyone sold even half that.

But for the sake of this discussion, let's assume you could eventually sell about half that - the next question would be over how long a period. Certainly not one to two years. So, given the amount of time it would take to develop said set of complete plans, and assuming one is doing so as a business, even the most optimistic assumptions would show that the payback certainly would not compensate you for the amount of work that you'd need to do in order to do this commercially - not in a realistic time period anyway.

Then you also need to consider that no-one in their right mind would buy a set of plans without them being verified through an actual built and flying airplane (at least I hope they wouldn't). So there again you have an additional investment of time and money in order to show that the design actually works.

Historically, the plan sets that were available were developed as a part of a project the designer did initially for himself, usually part time or after retirement. After he got done, he was able to turn around and make a salable package out of the project.

And finally, one also needs to consider the actual market. Assuming the sales interest in an amphib set of plans would be similar in proportion to the number of amphibs or float planes that are sold normally, the best number you might be able to estimate is about 1/4 to 1/3 that might be sold of a more conventional design.

The bottom line? Your sales may add up to a couple hundred sets but personally, I think even that is optimistic. So then the person must decide whether about 2,000 to 3,000 man-hours (ballpark to develop a decent set of plans, manufacturing drawings and assembly instructions) is a viable investment into something that would have so little potential of return.
 

Mac790

Well-Known Member
Joined
Jun 22, 2008
Messages
1,529
Location
Poznan, Poland
Unfortunately I went to school to become a mechanical engineer not an aircraft designer.
Sorry but I dont get it, what's a problem? There are few guys here that designing and building their own planes and they don't have even mechanical engineering title. Personally I think that you have three ways: hard way, expensive way and "easy way".

Hard way: you can learn everything by yourself so you will be able to design it by yourself.
Expensive way: you can hire someone for the job.
"Easy way": you can buy plans and modify them a "little bit". For example you can buy Osprey 2 plans and redesign the fuselage shape, or maybe replace wooden structure with composite one (of course you will have to recalculate it). I think that as long as you keep "original shape" flying surface, airfoils, CG, etc you should be fine but I'm newbie here so maybe I'm wrong.
 

Lee Schaumberg

Well-Known Member
Joined
Aug 28, 2003
Messages
215
Location
Northern Wisconsin
Hello
Sincere apologies if I angered the Adm or moderators on this board. It was not my intention. I can not reply to any board after lunch because by then I'm beyond any playing. If I angered any viewers with any thing but truth sorry.
Now an explanation of my posts.
The LSA aircraft is used because it has the widest appeal to any one with only a drivers license. I live in an area of this country with a lot of (open) lakes. Many parts of this country does not have lakes or has irrate people living on them. Only two manufactures make piston aircaft engines - Lycoming and Continental. 100-125 hp provides enough power to do the job I'm looking at. The number one problem that airplanes have is loss of vacumn pump ( all electric ). The number two problems are engine failure because of a lack of fuel ( pilots fault ) or a lack of ignition.
Lee
 

Rhino

Well-Known Member
Joined
Apr 8, 2004
Messages
771
Location
SW Ohio
Jabiru makes a piston engine in that HP range, and it's quite popular on LSAs, at least the homebuilt ones.
 

djschwartz

Well-Known Member
Joined
Jun 21, 2008
Messages
982
Location
Portland, Oregon
Hello
Fuel Capacity = 35 gallons
Range @ 75% = 7 hours no resrve
Speed = 120-125 @75%
Power = Continental O200 or IO240
The fuel quantity, range, and engine don't add up. An O-200 at 75% burns closer to 6.6 GPH (Continental's own numbers: .54 lb/hp/hr x 75 hp /6.15 lb/gal) and you need to allow for takeoff and climb at 100% prior to estimating range. Depending on what assumptions you make about cruise altitude for termination of the climb you'll probably need closer to 50 gallons
 

Blackhawk

Well-Known Member
Joined
Apr 18, 2008
Messages
196
Location
AUSTRALIA
Hi Lee,

Here,s a new Amphibian kit being released in early 2009. It's MTOW is 1350lb.

It's called a 'Sea Eagle' and made in Australia. No other info available yet.
 

Attachments

Last edited:

Lee Schaumberg

Well-Known Member
Joined
Aug 28, 2003
Messages
215
Location
Northern Wisconsin
Hello

After searching with 4 differant search engines for "Sea Eagle" I could only find that twin engined thing that I seen before. But in the process I thought of a great idea. How about tipping one of the removable wings straight up after landing and sail along using the flight controls? You could move around and pull up to a dock with out knocking every body off. I've never tryed sailing a seaplane yet.

I've also thought of a name for my amphibian too.
 
Last edited:

etterre

Well-Known Member
Joined
Aug 30, 2006
Messages
313
Location
St. Louis, MO, USA

Blackhawk

Well-Known Member
Joined
Apr 18, 2008
Messages
196
Location
AUSTRALIA
Hi Lee,

Sorry I haven't replyed to your comment about not being able to find any site for the Sea Eagle.

The reason you can't find anything is because I haven't put anything on the internet as yet.

As you can guess from that comment, we are the builders of the Sea Eagle.

When we get closer to releasing kits we will put it up on the internet.

Stay tuned.
 

Attachments

Kookaburra

Member
Joined
Dec 12, 2008
Messages
12
Location
Australia
WOW the Sea Eagle is the best looking and most practical amphibian I have seen for along time. I've been waiting for the right plane to come along and get my attention. This is looks like the one for me. This type of aircraft has it all why would you build anything else.

I would love to get the stats on it.

thanks
Kookaburra.
 

Blackhawk

Well-Known Member
Joined
Apr 18, 2008
Messages
196
Location
AUSTRALIA
Here's the Sea Eagle spec's you were wanting.

We will have three different Radial engines avalable for the Sea Eagle and they are:

CAPICITY ............HORSEPOWER.............. DIAMETER ............WEIGHT
1200cc .....................70HP ............................510mm ................<50kg
1600cc .....................95HP ............................610mm ................<65kg
2000cc .....................120HP ..........................710mm .................<80kg


And they are all DIESEL

These are still in development, but should be available towards the later part of 2009



 

Attachments

2
Group Builder
Top