Dandy Sport on floats

[flipstart]

I built a set of floats for my slow stick and plan on getting a Dandy Sport to also have floats. In looking at Cunningham's formula for float design, the width is only listed by gas engine size. I found out on the SS that width is as important as some of the other dimensions (which are expressed as a % of total length of floats). Has anyone seen any other info on the width dimension? Would like to build my Dandy with floats and lights in mind up front. My first set of floats on the SS were 1-3/4" wide and second set are 2-1/4 " measured at the widest point-all the difference in the world as far as handling in the water.

Seems like a plane weight vs width chart would be useful.

Flipstart

[fumblethumbs]

You might find this interesting reading Flipstart. It's an old MA article about model float design/calculations:http://users.rcn.com/llfc/floats/
-thumbs

[flipstart]

Thumbs-wow, I may not be able to sleep tonight thinking about all that data-but have to start somewhere-good info-Thanks

[peterv]

Wish you luck Flip! Mine was a failure. Mine is almost back together after dryout and draining of the wing, slight warp in on the fuse sides, begining to think that only foamies are good in water! Going to do some dry runs to check CG and stability with floats over grass. Maybe that is way no one posted that they put floats on a Dandy Sport. Sure was a great flying plane with wheels!

Pete

[flipstart]

Pete-sorry to hear about your Dandy-do have one yet but suppose to be a great plane-guess they will all get wet sooner or later-but flying off water is so much fun and I have to drive a ways to fly off land. What type of floats did you have?

[flipstart]

Pete-Flip here again-did not realize that was you later down the list with the Dandy that was having problems-ok, well would have to agree with the comment of too much AOA and step being back too far but let us know what happens next-

[peterv]

Flip, using foamfloats hollow 19", takeoff was OK, just very hard to control in the air, and landing. Live on a lake and been flying a heavy, much epoxied and taped Wingo, it flys and lands great, just gets tipped over in any wind while taxing! Not giving up yet!

Love the Dandy Sport though!

Pete

[flipstart]

Well you have me thinking about balsa though-my favorite plane material but on water, hate to think about a warped wing, having to water proof inside of fuselage, I build heavy anyway, my Dandy may never get off the ground or water. 19" is right length, hope you can get it worked out.

[BEC]

Hmmmm...... I'm in the process of putting a pair of 19 inch foamfloats.com floats on my Dandy Sport with hopes of flying at the Chilliwack float pond on Saturday. Sounds like I'd better be prepared to do a hand launch test flight at the club field Friday.

[peterv]

BEC, was looking at mine last night hanging from the rafters and noticed that the rear of one float was higher than the other by about 1/4 inch. Hmmm, wonder if that could have caused the eratic flight. Going to work on that rear float mount and rebend it. Takeoff was fine on a 280 with 3 cell ETec 1200. 15 to 20 feet and ROW! Was on step in 6 to 7 feet. Do try a over grass launch first!

Pete

[BEC]

Floats are on the DS, step is right at where the CG is supposed to be (but it balances about 1/2 inch forward of that). Total weight gain due to the floats is about 2 ounces (foamfloats.com 19 inchers that aren't the hollow ones).

Will test fly later today (after some sleep). Just range checking it tried to skitter across the cul-de-sac (was also checking out a Glowire installation). I think ROG from grass will be possible.

Power is EPS-300C-C on two LiPolys (either ETec-1200s or Thunderpower 2100s) and APC 10x7SF prop. ESC is a CC Pixie-20P that I special ordered from them waterproofed.

If the grass flying is OK, then water trials on Saturday in Chilliwack.

[peterv]

BEC, my step is about 1 inch behind the CG. However CG is still the same with the ETec 1200 2S1P. Using the EPS 100A the 280 and 10x8 prop. Worked great with wheels. Wish I would have tried over grass first!!

Good Luck!!!

Pete

[BEC]

Thanks to a snafu with child care I'm not in Chilliwack tonight and so will miss the float fly in the morning..... however, I did fly the Dandy Sport on floats in a park today. After getting the roll trim sorted out (this wing is also new and had a bit of wash-in on the left side), it was fairly fun to fly. The extra weight and drag was definitely noticeable, and with that much extra weight down low rolls are a bit more interesting.

It is not as fun as the DS on wheels, but the changes are similar to those I've seen on other planes when putting them on floats. I need to carry extra power on landing, not just glide in power off.

It will be interesting to see how it actually works on water. Maybe they'll go float fly in Chilliwack on Sunday, too and I'll get to go. We're going up in the morning.

[peterv]

BEC, glad yours worked out! I have found that in all water landings you MUST keep power on otherwise they nose up and stall nose down with the resulting tip-over! May work on mine this weekend and do a dry run over land first. Live on a lake so all I need is light winds and I'm ready to try again.

Pete

[BEC]

I FINALLY, one year later, got the Dandy Sport on floats on the water - at the Chilliwack float pond. It worked just great! This particular fuselage has an old 16T Astro 010 in it, which I run on 3s lithiums. I got about an hour on it Sunday with many touch and goes off the water as well as a fair percentage of the Dandy Sport's usual repertoire (inside and outside loops, rolls, Immelmanns, etc.)

I do wish for a water rudder - not much "traction" with the flat bottom floats.

There was also a GWS Tiger Moth 400 on GWS floats there Sunday morning and he has much better control on the water even without a water rudder - but those floats have a deep Vee bottom rather than a flat one.

[peterv]

Wow! BEC, you did it! I gave up on mine after that poor flight. Decided only float planes I have will be foam! That 30 min in the water sure warped the fuse and horiz stab. Had to replace the stab and drain out the wings! Plane still flys great with wheels though! Now have a Kyak and a dock on my shore for quick recovery. However almost 200 takeoff and landings this year and not one tip-over! Wow, talk about luck and all on a 5 year ols Wingo! BEC, have fun with yours! :)

Pete

[BEC]

A shot from yesterday at the Chilliwack float pond. I'll have to depend on someone else for in-flights, but here it is taxiing slowly.....

[peterv]

SWEEET!!!

Pete

[jimsp]

Aircraft-World (http://aircraft-world.com/shopexd.asp?id=2351) has some new lightweight floats that might work for the Dandy. I guess they also would be a good choice for the Tiger Moth. They are little over 17” long, only 55grams and cost $16. Although I’ve made several sets of floats I thought I’d give these a try on the Dandy.

[BEC]

Hmmmmm..... those might work. The ones in the picture above are the 19 inchers from foamfloats.com. I certainly wouldn't want to go any shorter than 17 inches.....

[BEC]

Here's one of a handful of shots Glen Peden took of the DS on floats.....

[peterv]

BEC, did you have any trouble with water entering the battery door?

Pete

[BEC]

No. The underside of the plane got less wet flying that Sunday on the pond than it gets when I fly off of damp grass (or skis). That might be different if it had been choppier, but not much up to the point where it would no longer make sense to try to fly off floats (with no water rudder).

[peterv]

Thanks BEC, I'll have to try it again, the Dandy Sport is such a good flying plane with the J250 and 1500 2S Tanic Lipos! Got some new floats to try from Canada, 20" and really well designed, inexpensive too! Good luck and keep the float side down.

Pete