Girvin .049 Seaplane
#28
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
Thanks for your patience. It is built and I have started covering. It was a slower process since as I built, I would make small changes to the plan and then build some more. Plus I was gone most all of this last week. I changed the width of the first former +1/4" and added a balsa stringer along the keel aft of the step to help with sheeting. I also decided on attaching the fin all the way through the body to the keel as opposed to attaching it just to the top of the sheeting. I will post some pics tonight and will maiden this week for sure.
Ya know, I wont have any water to float in until march/april! Take offs from snow will have to do for now. I have gotten a few requests for plans already even before it is finished and flown. It is hard 'cause I have been making changes to the plan constantly but I will post a final version here shortly.
Mike
Ya know, I wont have any water to float in until march/april! Take offs from snow will have to do for now. I have gotten a few requests for plans already even before it is finished and flown. It is hard 'cause I have been making changes to the plan constantly but I will post a final version here shortly.
Mike
#29
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
I promised a pic and here is what I have so far. Needs a little trim, some floats and install of the electronics but I WILL maiden on Saturday. It has been covered with a stolen minute here, a minute there... Frustrating I just don't have enough time in the day.
Edit - Airframe finished, installing electronics now.
Edit - Airframe finished, installing electronics now.
#31
RE: Girvin .049 Seaplane
Looks great congratulations, will wait for the maiden report.
Hope plane performs as good as it looks , let us know if you changed or improved anything from original plan during construction .
Hope plane performs as good as it looks , let us know if you changed or improved anything from original plan during construction .
#32
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
During construction, I changed the plan to widen the first former (F1) by 1/4", added a balsa stringer along the keel behind the step to aid in sheeting, and I changed the fin so it passes all the way through the fuselage and glues to the keel for strength. No major changes otherwise. Testing balance right now shows I may need to push the electronics forward as much as possible or lengthen the nose for future models. It's close... I estimate final weight to be 14-15 oz.
#33
RE: Girvin .049 Seaplane
Flug I will consider your comments before I start building mine, all info you can share will be very helpful.
Hope maiden flight becomes a great experience , will wait for your report.
Hope maiden flight becomes a great experience , will wait for your report.
#34
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
Plane is charging for maiden tonight, if the wind goes down. We have had 25-30 mph winds the last several days and then I came home yesterday to water in my basement! Needless to say, it has been frustrating for the lack of time on this project.
However the plane is done, and I'm pretty happy with the way it turned out so far. Span 30" and weight came in at 13 7/8 oz, which could be lightened up some with lightening holes in some of the ply. I'm using a 300mah Nimh battery pushed all the way up to the front for balance. I think I might play around with lengthening the nose slightly to help with this. 2 HS65 Hitec servos power the R/E and I am using a 6ch nano receiver (it was handy and it further served as nose weight. I also have an .061 Norvel that is begging to used on this one - (thats why I went with the pylon for the external tank) but I wanted to power it with the cox for the first flights.
So hopefully maiden tonight or early tomorrow morning if the wind goes down!
However the plane is done, and I'm pretty happy with the way it turned out so far. Span 30" and weight came in at 13 7/8 oz, which could be lightened up some with lightening holes in some of the ply. I'm using a 300mah Nimh battery pushed all the way up to the front for balance. I think I might play around with lengthening the nose slightly to help with this. 2 HS65 Hitec servos power the R/E and I am using a 6ch nano receiver (it was handy and it further served as nose weight. I also have an .061 Norvel that is begging to used on this one - (thats why I went with the pylon for the external tank) but I wanted to power it with the cox for the first flights.
So hopefully maiden tonight or early tomorrow morning if the wind goes down!
#35
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
Was able to get in one try before dark. First time for this engine and it was developing low power. With the 5x3-3blade, it was just not enough for ROG. It skipped along the snow and made a couple leaps into the air but it was just not enough. Will try switching engine and prop and tomorrow's another day.
#36
RE: Girvin .049 Seaplane
Woowww Flug it sure looks nice , great job you' ve done , you think lengthening the nose about an inch or so could be enough?
Hope wind gives you a break and the chance for the final maiden report.
Hope wind gives you a break and the chance for the final maiden report.
#40
Senior Member
Join Date: Jul 2003
Location: Plattsmouth,
NE
Posts: 682
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
dieFluggeister,
The plane looks great. Looks like you have some upthrust too! I would ditch the 3 blade prop and use a 6 x 3 Tornado. Do have enough clearance for the 6 x 3? Keep us posted.
Hec
The plane looks great. Looks like you have some upthrust too! I would ditch the 3 blade prop and use a 6 x 3 Tornado. Do have enough clearance for the 6 x 3? Keep us posted.
Hec
#41
Senior Member
Join Date: May 2005
Location: Savage,
MN
Posts: 567
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
Really nice!!! I like the wheels on the sides. You're making me want to go watch "Tales Of The Golden Monkey" reruns. I can't beleive you got it so light!! Todd
#43
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
Got the first flight in tonight! But I probably should have waited.
Learned a couple things...
1. The wing floats fold up in a crash (like they're s'posed to)
2. It gets dark amazingly fast in the last three minutes of daylight.
3. Three minutes at full throttle in the dark in windy conditions can be the longest three minutes of your life.
I ended up switching to a Surestart with a one ounce external tank and used a 6x3.5 prop. It was definitely pulling harder. It took off from the snow in about 30 feet but was a handful - like the CG was too far back. After an unscheduled landing, I remembered that the surestart was a 'shorter' engine (I had taken the snorkel intake off) and that threw the balance off just enough to make it squirrely. I added 5/8 oz weight to the nose and on the second flight it flew much better with the CG slightly behind the bend in the wing.
By then though the sun had disappeared below the horizon and twice I lost orientation but regained control. Trimming took a surprising amount of up-trim. I will need to look into that for possible changes.
Overall the plane flew ok, but it needs some adjusting under better conditions.
Learned a couple things...
1. The wing floats fold up in a crash (like they're s'posed to)
2. It gets dark amazingly fast in the last three minutes of daylight.
3. Three minutes at full throttle in the dark in windy conditions can be the longest three minutes of your life.
I ended up switching to a Surestart with a one ounce external tank and used a 6x3.5 prop. It was definitely pulling harder. It took off from the snow in about 30 feet but was a handful - like the CG was too far back. After an unscheduled landing, I remembered that the surestart was a 'shorter' engine (I had taken the snorkel intake off) and that threw the balance off just enough to make it squirrely. I added 5/8 oz weight to the nose and on the second flight it flew much better with the CG slightly behind the bend in the wing.
By then though the sun had disappeared below the horizon and twice I lost orientation but regained control. Trimming took a surprising amount of up-trim. I will need to look into that for possible changes.
Overall the plane flew ok, but it needs some adjusting under better conditions.
#44
RE: Girvin .049 Seaplane
ORIGINAL: dieFluggeister
Trimming took a surprising amount of up-trim. I will need to look into that for possible changes.
Overall the plane flew ok, but it needs some adjusting under better conditions.
Trimming took a surprising amount of up-trim. I will need to look into that for possible changes.
Overall the plane flew ok, but it needs some adjusting under better conditions.
#45
My Feedback: (28)
Join Date: Jan 2003
Location: san antonio,
TX
Posts: 23
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
Wow! the Cute factor is at the top of the scale.
I've built dozens of small seaplanes; and they all needed 3-4 degrees upthrust.
And if you make the fuselage wide enough, they dont need spray rails. Check out the Puddlemaster for example; it actually looks FAT!
But it gets off the water quickly with no nose-dives.
I built a Herr 1/2A seaplane with the main fuselage bulkheads replaced with new wider dimensions, an inch wider in the widest area, and it does not submarine like the stock one does.
BTW I'm flying the Puddlemaster with a Norvel 074 with a 6-4 prop; I added ailerons and raised the stab 1" to keep it dry, and doubled the volume of the wing floats. Works great.
How can I get the PDF file for your Girvin?
I've built dozens of small seaplanes; and they all needed 3-4 degrees upthrust.
And if you make the fuselage wide enough, they dont need spray rails. Check out the Puddlemaster for example; it actually looks FAT!
But it gets off the water quickly with no nose-dives.
I built a Herr 1/2A seaplane with the main fuselage bulkheads replaced with new wider dimensions, an inch wider in the widest area, and it does not submarine like the stock one does.
BTW I'm flying the Puddlemaster with a Norvel 074 with a 6-4 prop; I added ailerons and raised the stab 1" to keep it dry, and doubled the volume of the wing floats. Works great.
How can I get the PDF file for your Girvin?
#46
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
Getting the width of the fuselage right is a fine art. Wider does help it plane out on water, but it also makes it skip on landings. I have not had a chance to float Girvin yet - I don't even have a bath tub! We had a blizzard here the last several days and I have been unable to test fly it any more. I would like to get a couple more flights logged make a few more changes to the plan and then give it out for release.
#48
Join Date: Oct 2002
Location: Chilliwack, BC, CANADA
Posts: 12,425
Likes: 0
Received 22 Likes
on
19 Posts
RE: Girvin .049 Seaplane
I'm late to the game on this since I've been fooling around with some other stuff more the past few days.
I hope I'm wrong but I think the nose may be a little short to provide the proper lift while on the water for riding over the wavelets instead of through them. You're well along already though so I'd suggest just keep going. You can always cut off the nose and graft on a longer one if it proves to be a problem. Don't forget to use something like packing tape or whatever to seal the gear access opening under the wing. On a small model like this water will get in EVERYWHERE without a full sealling. Models of this sort are where I really like Nyrods just because they do so well at allowing for minimal openings in the outer finish of the model.
If it ends up needing a longer probiscus grafted on perhaps add in some plug in gear tubes so it becomes a full fledged amphibian instead of "just" a boat.
I hope I'm wrong but I think the nose may be a little short to provide the proper lift while on the water for riding over the wavelets instead of through them. You're well along already though so I'd suggest just keep going. You can always cut off the nose and graft on a longer one if it proves to be a problem. Don't forget to use something like packing tape or whatever to seal the gear access opening under the wing. On a small model like this water will get in EVERYWHERE without a full sealling. Models of this sort are where I really like Nyrods just because they do so well at allowing for minimal openings in the outer finish of the model.
If it ends up needing a longer probiscus grafted on perhaps add in some plug in gear tubes so it becomes a full fledged amphibian instead of "just" a boat.
#49
Senior Member
Thread Starter
Join Date: Mar 2004
Location: New London, MN
Posts: 752
Likes: 0
Received 0 Likes
on
0 Posts
RE: Girvin .049 Seaplane
I agree Bruce and I have already lengthened the nose on the plan 1.5 in.
The wing saddle is sealed with silicone rubber gasket formed with wax paper around the wing and seems to be holding the snow melt and fuel out ok. Water is always a bugger though. Using sullivan flex cable pushrods to also help keep water.
Here is a shot of my first float test today. Despite what it looks like in the picture, the open water was too small for a water takeoff and the ice is so thin around there that if the plane got stranded, I would surely have to wait for weeks to retrieve it. It's stance in the water was about like I expected. Now where to find bigger water....
The wing saddle is sealed with silicone rubber gasket formed with wax paper around the wing and seems to be holding the snow melt and fuel out ok. Water is always a bugger though. Using sullivan flex cable pushrods to also help keep water.
Here is a shot of my first float test today. Despite what it looks like in the picture, the open water was too small for a water takeoff and the ice is so thin around there that if the plane got stranded, I would surely have to wait for weeks to retrieve it. It's stance in the water was about like I expected. Now where to find bigger water....