Looking for O-320 firewall forward and float fin

[Forrest Barber]

Re: Looking for O-320 firewall forward and float fin

Robert please explain to the tribe the "changes" you have made to your ship over the years! The ventral fin was used on the pre-war or any three hinge BC12D because they had the "smaller" fin thus less "fixed vertical surface" aft of the C.G. You who mentioned that the longer nose SHOULD lead to the additon of the ventral fin are correct.
It all has to do with "fixed vertical" surfaces fore & aft of the C.G. During tests with the F-19 and the floats used at that time , the fin was not necessary. BY THE WAY! I loaned the one from here to someone to copy and it disappeared , like the Taylorcraft Owner Club shock cord tool , spreasd the word. That is why We now get high deposits. I do have the drawing.
When I got my seaplane rating I pointed out to the instructor and the Examiner that that ship would not meet certification on the Yaw Stablility tests. A BC12D-85 on 1320's .... Shhhhh. It just takes a person being awake on the rudder pedals.

[Robert Bradbury]

Re: Looking for O-320 firewall forward and float fin

Robert please explain to the tribe the "changes" you have made to your ship over the years! The ventral fin was used on the pre-war or any three hinge BC12D because they had the "smaller" fin thus less "fixed vertical surface" aft of the C.G. You who mentioned that the longer nose SHOULD lead to the additon of the ventral fin are correct.
It all has to do with "fixed vertical" surfaces fore & aft of the C.G. During tests with the F-19 and the floats used at that time , the fin was not necessary. BY THE WAY! I loaned the one from here to someone to copy and it disappeared , like the Taylorcraft Owner Club shock cord tool , spreasd the word. That is why We now get high deposits. I do have the drawing.
When I got my seaplane rating I pointed out to the instructor and the Examiner that that ship would not meet certification on the Yaw Stablility tests. A BC12D-85 on 1320's .... Shhhhh. It just takes a person being awake on the rudder pedals.

Forest,
I restored a 46 BC12D with latest spars, and beafed up the fuse in
a couple of areas that were known to be the weaker points. I installed a
C90 on a stock 65hp mount instead of using the longer mount. I dished the
firewall to clear the mags and used the B&C lightweight alternator and starter.
I built up a set of 1650 floats( Aeroset made in Quebec) very similar to the
Aqua design. The floats were set up per the float manufactures recomendations by having the step one inch fore or aft of the C of G, I can't
remember which it was its been so long. Most floats have an opening angle
between 3 to 6 degrees. I opted to go 4 degrees and it seems to be about
right. I've actually tried a couple of degrees both sides of 4 degrees with little noticeable difference. Once the aircraft was levelled and the float angle
set, I proceeded to make all of the rigging . I have a current approved gross
weight of 1650LB based on a climb test I did . The forward attach points and
hardware are identical to most certified aircraft however, I chose to use the
prexisting rear float bushing as used with 1320 edo floats. After 200 hrs of
operation this attachment point is still in great shape so the question is:
Does anyone know any good reason why I should upgrade to the later clamp on style fitting or was this newer clamp on only necessary because the float
bushing was removed from later production aircraft ???

So here I am 200 hrs later still concerned about yaw stability and whether or
not I should add the rear ventral fin. Most suggest that I should install one and I have decided to indeed do so in the spring . Another key that I may have just realized by writing the above is that I have a shorter moment from the C of G to the engine whereas later aircraft had larger engines with a longer moment. This combined with a bigger float furthur forward from the
C of G is probably my problem .

[crispy critter]

Re: Looking for O-320 firewall forward and float fin

Robert,
I have an 0290-D2 Lycoming I will sell....pretty cheap too. It has 350smoh and is a certified engine with logs back to the late 1960's or early 1970's.

[Robert Bradbury]

Re: Looking for O-320 firewall forward and float fin

Robert,
I have an 0290-D2 Lycoming I will sell....pretty cheap too. It has 350smoh and is a certified engine with logs back to the late 1960's or early 1970's.

Just the engine or do you have a firewall forward package?

[crispy critter]

Re: Looking for O-320 firewall forward and float fin

just the engine, I have 2 props but I want to wait and see which one works best on my Starduster with the O320 before I sell one.

[Robert Bradbury]

Re: Looking for O-320 firewall forward and float fin

just the engine, I have 2 props but I want to wait and see which one works best on my Starduster with the O320 before I sell one.

I know of a few local guys who swear by the O-290 in that the cruise is the
same but burns less gas. Now this is on a float plane with a Borer prop, in a
fast plane their may be a difference .

I have a freind that has the O-290d2 in a T on 1800 edos with fluted bottoms.
He cruises at 115. He's actually thinking about selling it to get a super cub .

[perryv1]

Re: Looking for O-320 firewall forward and float fin

I know a guy that tryied one of those on full lotis floats and it was a Dog.He almost had to truck it home after he he landed in a large lake.just wouldn't get going fast enough to get off the water, after about a mile or so, he got it off.
Im not really impressed with those floats,Ive seen a Kitfox with them on it and it wouldn get 2 160 guys airborn eighter.
PV
I dont think a fin would be that hard to make Should be a drawing for one somewhere.

[matsuthunder200]

Re: Looking for O-320 firewall forward and float fin

I have seen a few of the fins you are talking about all of them were on 65hp t-crafts with floats which they haft to have for certifacation on floats. At least thats what the paperwork i had at one time said. I have about 2000 hrs on floats in a t-craft and never have had any kind of turning problems as severe as you have. I have practiced spins on floats and have always recoverd in no time about a turn and a half. With an instructor...As far as doing slips i think they slip alot better on floats than on wheels.. I think it might be like you said to big of floats with the short mount and lack of power to opperate at gross wt. I have a 90 hp
bc12-d with 1320s she also has the 1500 lb gross wt in, i have about a 650 lb usefull load. at gross she flys great gets off the water good. and feels very stable in turns. I have flown the 125 hp tcraft with the 1650 floats and the 150 hp one with the 1650s and they both flew great. they just seem to take a little more rudder and sometimes opp,aleron in a turn, as most float planes.
By the way they both sold the planes and went back to a 100p or 90 with the 1320 or 1400s. They start to get to heavy with them bigger motors the stall speeds are in the fiftys they had to add more gas tanks and in the end they had more money in them than a cub. I dont think you can even convert one to a 125 now with the faa the way it is. Have you flown her on wheels??

[stormman]

Re: Looking for O-320 firewall forward and float fin

Robert is a Brit Lance. No FAA for him

[matsuthunder200]

Re: Looking for O-320 firewall forward and float fin

wow no faa what a deal..

[Robert Bradbury]

Re: Looking for O-320 firewall forward and float fin

wow no faa what a deal..

This Robert isn't a Brit, you must have been thinking about Robert Lees.

I have to deal with Transport Canada for my Amateur Built (experimenntal) in
your neck of the woods . I have a little freedom no doubt, but I have to say
things have been pretty smooth thus far. As long as its been done by others
changes are very straight forward . Maybe I shouldn't speak too loud, I'm sure
they are spying on me!!!

Robert Not the Brit, but closer to them in North America than anyone else.

[stormman]

Re: Looking for O-320 firewall forward and float fin

OK,OK my mistake
He's a Newfie from Newfoundland , i was born in St John's Newfoundland, probably some relation

[Robert Bradbury]

Re: Looking for O-320 firewall forward and float fin

I know a guy that tryied one of those on full lotis floats and it was a Dog.He almost had to truck it home after he he landed in a large lake.just wouldn't get going fast enough to get off the water, after about a mile or so, he got it off.
Im not really impressed with those floats,Ive seen a Kitfox with them on it and it wouldn get 2 160 guys airborn eighter.
PV
I dont think a fin would be that hard to make Should be a drawing for one somewhere.

Putting anything on floats that is not factory tested is a ambitious project.
If your saying the guy had a T with O-290 then it should have been a rocket
getting out,climbing and cruising. If he couldn't get it up " scuz the pun," I would suggest that he had too flat of an opening angle between the float centerline and the wing/fuse centerline . The opening angle should be between 3-6 degrees. Too flat and he'd be dragging the back of the floats during rotation. Too much opening angle would cause the plane to dig in in the bow on the step. I'm
not that fond of the Full Lotus floats either except, they can be used off of wet grass and on the snow in the winter negating the
need to change over .

Robert

[Robert Bradbury]

Re: Looking for O-320 firewall forward and float fin

OK,OK my mistake
He's a Newfie from Newfoundland , i was born in St John's Newfoundland, probably some relation

I had forgotten that Norm, I seem to remember that you were born here
and moved away at a early age........right ?

Robert

[stormman]

Re: Looking for O-320 firewall forward and float fin

roger that