mmattockx

I think it is more like 7 or 8 times, but yes, a round strut is about the worst aerodynamic shape you could have. It can also cause resonance and vibration problems due to the vortex shedding coming off of it. Adding a tapered trailing edge would be a huge improvement over nothing. You could also make a fairing the way Goldberg does on their Ultimate bipe and Extra 300 kits, with a piece that slides on from the side and adds a leading and trailing edge.

Mark

Mike Connor

My Feedback: (5)

The drag coefficient increases with speed when using a round shape.
Attachment form NASA web site.

hooty301

Some very good info! I love the way you guys think.
Im gonna make a seperate set of tubes with a shorter length and I will definatly have to do some experimenting with them.

hooty301

Just thought Id show you guys a few pics of my flatbottom with a Jettstream on the 91fx, setup with water rudder. Ive got a topspeed of 56mph with this combo.

The fuel tank is set for the pictures only, I normaly keep it insualated with foam to help with the vibration.

daven

My Feedback: (1)

That looks like a lot of fun Hooty, but I'd rather go 190 in the air

Lomcevak Duck

My Feedback: (14)

You do good work with wood Hooty. It looks great.

hooty301

Thanks for the kind words Lomcevac Duck.

Daven wrote:
I can only imagine the rush[8D]


Heres some more progress on my rigger, I shortend the boom tubes some in the second pic. Weight is at 1lb 14oz in the first pic a lil more in the others.

hooty301

I want to thank you guys for helping me select a good engine for my project.

I went with a 90lx fire.

jettlag

was it rich?

hooty301

Jetlag wrote:
I havent run it yet.

BTW Mr Jett, this thing is a work of art!


Thankyou[sm=cool.gif]

hollander101

Wow that thing looks sweet, how has everything been going?? I have got to get some pics posted of my plane that I am working on I will have the other wing put together tonight do you have any pointers about wings??? As I see you have a wing on the back of your boat just how big is it??

hooty301

Hollander101 wrote:
Sorry about the delede response, somehow I missed the post.

Thanks, glad you like it. Things are going perty good here, how about yourself?

Im no expert on wings, these guys on here are the pros. Is it a scratch build or kit? The wing on my boat is around 18 inchs in span.

hooty301

Well Im getting perty close to being finished heres a few pics.

HaveBlue

you know your gonna have to get a video of this thing hauling..dont you

proptop

My Feedback: (8)

That's really cool man
Pretty spiffy (does anybody else still use that word?) engine mount/pylon too[8D]

Craig-RCU

I think that there is a law to that effect in most states that if you build something that looks like it could break the sound barrier, you have to post video on RCU of a speed-run. You don't want to go to jail over this do you Hooty? Also, tell us more about that metal engine mount; is it stainless steel, aluminum?

freakingfast

My Feedback: (3)

I dont see any control surface for when it leaves the water and wants to be a plane

HaveBlue

I doubt to much of that hull? (fuse with pylons?) will see much water..besides I just want to hear that Jett 90 get on the pipe..take heed, you best included control surfaces for both water and air

cncswiss1

I agree it needs elevons, or at least an elevator

freakingfast

My Feedback: (3)

Some kind of horzontal control surface placed fore or aft and connected to a gyro would quickly help if the hull's pitch gets out of contol.....or level flight

hooty301

Thanks fellows, Ill definatly get some video for you guys.


LOL..no I dont wanna go to jail, will post video

The engine stand is aluminum.

asmithnc

I am such a fan of Hooty's work..... way to do BRO. For the video thingy.... I will host it on a dedicated site for you We ALL can see it in the quality it deserves.

Also when you come to NC for the meet my offers still stands. I'll put you in a 100mph speed boat so you can stretch the legs on your creation.

mike the snake

56mph with an air boat might just be the world record! You should look into that.

hooty301

Andy wrote:
Thanks Andy!

Cant turn that offer down

mike wrote:
Ive seen 56mph out of it but it wasnt documented, the fastest documented speed from an airboat so far that I know of is 53.3mph.

Record run

[link]http://www.rcairboats.net/Videos/Others/Nitro/Nitro533.wmv[/link]

mike the snake

I've been following that thread.

If you've already gone 56, then you should be able to eek even more speed from it.

GIT er Done Man! Take that World Record! That's something you can keep forever and not many people can say that.

I'm gunning for the all out world record for ALL model aircraft.