# CF composite part 103. Possible?

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#### Aviator168

##### Well-Known Member
Been gathering data and doing some calculation for a CF composite part 103. Here is what I got so far

. Engine. mount & prop weight < 60 lbs that will probably land me 25 horses. I can probably do better with a two stroke.
. 125 ft^2 removable wing weighting less than 75 lbs. I estimated using solid core (blue foam, Rutan style) construction with flaperons.

That leave me 119 lbs for the fuse and the tail. Here is the question. Is it possible to build a fuse + tail within that weight limit for a LSA aircraft? I am trying to kill two birds with one stone here. The goal is to build a part 103 first, and when I am tire of it, replace the wing and the engine, then register it as a ELSA. If the answer is yes. The next question is. Is it possible to build a fuse that has enough room spared for a second upholstery for later conversion to a tandem ELSA? Your thoughts?

BTW. It is also acceptable if structural re-enforcement is required in the conversion process without any cutting.

#### Hot Wings

##### Grumpy Cynic
HBA Supporter
Log Member
Take a look at the E-Go mentioned recently in another thread. While not an ultralight by US standards it does claim to meet US part 103 weight limit. If it had more than 50% span flaps it would meet the stall speed - as determined by the AC.

It should give you a good baseline to work from to determine just what is possible.

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#### Aviator168

##### Well-Known Member
According to that spec sheet. It is possible. Anyone got the construction info of the e-Go?

#### danmoser

##### Well-Known Member
35 knot min., 100 knot max. speed..
Way too fast for 103 legal requirement .. which is <24 knots min. & <55 knots max.

#### Aviator168

##### Well-Known Member
35 knot min., 100 knot max. speed..
Way too fast for 103 legal requirement .. which is <24 knots min. & <55 knots max.
Even a full span flap will not cut it. It is also over weight. However, I can see the possibility of a CF composite part 103 with a fuse tough enough for ELSA.

#### Hot Wings

##### Grumpy Cynic
HBA Supporter
Log Member
Even a full span flap will not cut it. \
To meet the 24 kt stall speed, no. But to meet the terms of A.C. 103-7 as they relate to stall speed all that is required is a double surface airfoil, >50% flaps and 116 ft2

It has double surface airfoil and more than 116ft2 of wing. Artificially limit the cruise speed, again legal per A.C. 103-7, and it becomes a legal part 103 ultralight. That is IF it really makes the claimed weight.

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#### bmcj

##### Well-Known Member
HBA Supporter
[Subject title of thread: CF composite part 103. Possible?]

Been gathering data and doing some calculation for a CF composite part 103. Here is what I got so far

That leave me 119 lbs for the fuse and the tail. Here is the question. Is it possible to build a fuse + tail within that weight limit for a LSA aircraft? I am trying to kill two birds with one stone here. The goal is to build a part 103 first, and when I am tire of it, replace the wing and the engine, then register it as a ELSA. If the answer is yes. The next question is. Is it possible to build a fuse that has enough room spared for a second upholstery for later conversion to a tandem ELSA?
Wait...

Aviator, you are in New York, so I'm assuming you are referencing U.S. rules and nomenclature. For clarification, are you trying to make this as a Part 103 ultralight (as the title says) or as an LSA (per your first post)? I'm guessing Part 103 ultralight, but wanted to make sure before we go down the wrong path with advice.

Bruce

#### BBerson

##### Light Plane Philosopher
HBA Supporter
There is no ELSA (Experimental Light Sport Airplane) category of Homebuilt registration since 2008 or 2010.
Only Experimental-Amateur Built. It can qualify as LSA but not registered as such.

#### bmcj

##### Well-Known Member
HBA Supporter
One of the cutest ugly plans I've ever seen! Doesn't seem to have caught on here.

ZJ Viera Compilation + Bounce Landing!! - YouTube
With the exception of the engine placement, I think the ZJ Viera is an attractive design. Of course, with the engine and prop raised up in front of the pilot's face, it gives new meaning to the term "headwind". :gig:

#### danmoser

##### Well-Known Member
ZJ Viera is light! .. empty wt. = 170 lb (77 kg) .
Hollow molded wings with molded D-tube & ribs & cloth covering construction.
Available in tricycle & monowheel gear.
Manufacturing & distribution rights were for sale a couple years ago .. not sure of current status.

#### Aviator168

##### Well-Known Member
Wait...

Aviator, you are in New York, so I'm assuming you are referencing U.S. rules and nomenclature. For clarification, are you trying to make this as a Part 103 ultralight (as the title says) or as an LSA (per your first post)? I'm guessing Part 103 ultralight, but wanted to make sure before we go down the wrong path with advice.

Bruce
Yes. I live in NY. I am trying to build a Part 103 UL with a fuse that is LSA capable by just swapping out the wing/engine and possibly the HS/Rudder.

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#### TFF

##### Well-Known Member
Every 103 is LSA capable. Just needs an N number and DAR inspection. No going back and forth legally.

#### Aviator168

##### Well-Known Member
Every 103 is LSA capable. Just needs an N number and DAR inspection. No going back and forth legally.
You are just saying this for argument sake. See what happens when swap a bigger engine on ZJ Viera and go to the upper LSA speed limit, or put a pax on the plane (if it would carry the extra load).

#### Aviator168

##### Well-Known Member
There is no ELSA (Experimental Light Sport Airplane) category of Homebuilt registration since 2008 or 2010.
Only Experimental-Amateur Built. It can qualify as LSA but not registered as such.
OK. Can sports pilots fly it then?

#### saini flyer

##### Well-Known Member
Not in composite but Brian Carpenter is doing something similar to your goal with EMG-6.
EMG6

Yes. I live in NY. I am trying to build a Part 103 UL with a fuse that is LSA capable by just swapping out the wing/engine and possibly the HS/Rudder.

##### Well-Known Member

The longer answer... well, then you'd have to start paying my salary ;-)

#### Aviator168

##### Well-Known Member
Not in composite but Brian Carpenter is doing something similar to your goal with EMG-6.
EMG6
If more people can think along this idea, it would eventually give current LSA manufacturers and the FAA a headache. You are talking about a kit plane maker that don't have deal with the 51% rule. That was actually the idea.