Cox Engines Forum
You are not logged in! Please login or register.

Logged in members see NO ADVERTISEMENTS!


Modified 1/2a Skyray  - Page 2 Cox_ba12




Modified 1/2a Skyray  - Page 2 Pixel

Log in

I forgot my password

Search
 
 

Display results as :
 


Rechercher Advanced Search

Latest topics
» Introducing the new - "QZ" RR-1
by Boats13 Today at 10:19 am

» STUKA bomb dimentions needed
by latole Today at 9:36 am

» Indexing COX cylinders
by davidll1984 Today at 7:56 am

» Another of C.T. engines cleaned ---- Cox Tee Dee .09 --- Just today (3/26/2024) more Cox parts
by Yabby Today at 7:47 am

» Introducing our Cox .049 TD Engines
by Yabby Today at 6:33 am

» 1/2a Skyray plans?
by 944_Jim Yesterday at 10:14 pm

» Postage stamp backplates
by JPvelo Yesterday at 8:52 pm

» my attempt at making an exhaust throttle for Cox .049
by roddie Yesterday at 8:20 pm

» Cosmic Winds, - Big Guy, Little Guys, Silver Guy and Wounded Guy.
by rsv1cox Yesterday at 5:18 pm

» My friend Ramón, his Cox .09 & Cox .010
by MauricioB Yesterday at 12:31 pm

» Parts Cox TD-4
by rsv1cox Yesterday at 8:40 am

» On ebay a very special Cox engine
by davidll1984 Yesterday at 6:32 am

Cox Engine of The Month
March-2024
balogh's

"COX Budapest" .049 engine



PAST WINNERS
CEF Traveling Engine

Win This Engine!
Gallery


Modified 1/2a Skyray  - Page 2 Empty
Live on Patrol


Modified 1/2a Skyray

Page 1 of 2 1, 2  Next

Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  roddie Fri Sep 19, 2014 6:49 pm

Nice! It seems plenty responsive even at those high speeds. Are you using a 5" prop? I wonder whether a 6 x 2 or 3 would slow it down 10-15 mph... enough to let you "carve"  your corners more? Were you able to get an average lap-time/mph estimate? I'm curious.. only because I don't know what an average lap-time should be.. for a given line-length for 1/2A "Precision Aerobatics". Do you have any 6" left-hand props you could try? What the heck... a left-hand prop will help with launching.. and pull better in breezy conditions. I'm planning on running a 6 x 2 L/H on my PT19 tomorrow... but it will be on much shorter lines.. Affraid or WOW!
roddie
roddie
Top Poster
Top Poster

Posts : 8156
Join date : 2013-07-17
Age : 64
Location : N. Smithfield, Rhode Island

http://www.stilburnin.com

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  JPvelo Fri Sep 19, 2014 9:18 pm

roddie wrote:Nice! It seems plenty responsive even at those high speeds. Are you using a 5" prop? I wonder whether a 6 x 2 or 3 would slow it down 10-15 mph... enough to let you "carve"  your corners more? Were you able to get an average lap-time/mph estimate? I'm curious.. only because I don't know what an average lap-time should be.. for a given line-length for 1/2A "Precision Aerobatics". Do you have any 6" left-hand props you could try? What the heck... a left-hand prop will help with launching.. and pull better in breezy conditions. I'm planning on running a 6 x 2 L/H on my PT19 tomorrow... but it will be on much shorter lines.. Affraid or WOW!
For cox flying I use a master airscrew 6 x3 cut down to 4.75. I like them to fly fast!

Jim
JPvelo
JPvelo
Diamond Member
Diamond Member

Posts : 1969
Join date : 2011-12-02
Age : 56
Location : Colorado

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  Cribbs74 Fri Sep 19, 2014 10:18 pm

Thin airfoil likes speed.

Roddie you would be hard pressed to get a 5 sec lap time out of a 1/2A. Although I would love to make that happen for myself.

As it stands when I fly 1/2A I hang on, but bigger stuff I am more relaxed.

Cribbs74
Cribbs74
Moderator

2022 Supporter

2023 Supporter

2024 Supporter

Posts : 11892
Join date : 2011-10-24
Age : 50
Location : Tuttle, OK

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  roddie Sat Sep 20, 2014 9:06 am

Cribbs74 wrote:Thin airfoil likes speed.

Roddie you would be hard pressed to get a 5 sec lap time out of a 1/2A. Although I would love to make that happen for myself.

As it stands when I fly 1/2A I hang on, but bigger stuff I am more relaxed.


I guess I figured that the idea behind adding flaps to this model was an attempt to improve it's PA capabilities. Maybe it's just too fast with the slab-wing combined with Jim's "hotrod reedies"..  Cool

Jim, how does the flapped version's performance compare to the original design? Let's say you had both versions involved in a combat match.. all else equal (pilot's ability, engine set-up, fuel, props) Do you feel that the flapped version would have an advantage? Does it feel like it turns any tighter or quicker?

I have mixed feelings about the use of flaps for C/L stunt. Do they really help to turn the airplane around it's pitch axis? I would think that a well designed tail-plane moment with adequate span and elevator/stabilizer proportions would handle the job of pitching the model, without the use of flaps. I feel that an un-flapped fully-symmetrical wing works in unison with the models center of gravity when pitch is altered; changing it's angle of attack. Flaps are for generating "lift"... which; when you think about it.. is working against turning the airplane around it's pitch axis. Maybe I'm full of crap... Laughing
roddie
roddie
Top Poster
Top Poster

Posts : 8156
Join date : 2013-07-17
Age : 64
Location : N. Smithfield, Rhode Island

http://www.stilburnin.com

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  JPvelo Sat Sep 20, 2014 4:05 pm

Roddie,
It flys much better with the flaps. Whereas the stock plane mushes through maneuvers like a slab wing plane this grooves much more like a plane with a built up wing.  It's an easy enough mod on a slab winger with a big enough performance gains I will probably to it on all my slab wingers from now on.

Jim
JPvelo
JPvelo
Diamond Member
Diamond Member

Posts : 1969
Join date : 2011-12-02
Age : 56
Location : Colorado

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  Theo Kleynhans Mon Sep 22, 2014 12:35 am

Hi Guys

Could someone please paste the link of the video.

I still cannot open the way it it shown.

Theo
Theo Kleynhans
Theo Kleynhans
Gold Member
Gold Member

Posts : 196
Join date : 2013-12-30
Age : 42
Location : South Africa

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  roddie Mon Sep 22, 2014 1:46 am

Theo Kleynhans wrote:Hi Guys

Could someone please paste the link of the video.

I still cannot open the way it it shown.

Theo

Here you go..

https://www.youtube.com/watch?v=0RjoEefb0sE
roddie
roddie
Top Poster
Top Poster

Posts : 8156
Join date : 2013-07-17
Age : 64
Location : N. Smithfield, Rhode Island

http://www.stilburnin.com

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  getback Mon Sep 22, 2014 8:10 am

Jim ; looks like it flew real well nice and smooth. On the flaps when elevator is up are the flaps in down position and vise versa?? Thanks Eric Very Happy
getback
getback
Top Poster
Top Poster

2022 Supporter

2023 Supporter

Posts : 10028
Join date : 2013-01-18
Age : 66
Location : julian , NC

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  JPvelo Mon Sep 22, 2014 11:04 am

getback wrote:Jim ; looks like it flew real well nice and smooth. On the flaps when elevator is up are the flaps in down position and vise versa?? Thanks Eric Very Happy  
Eric,
That's exactly how it works. It tightens up the corners.

Jim
JPvelo
JPvelo
Diamond Member
Diamond Member

Posts : 1969
Join date : 2011-12-02
Age : 56
Location : Colorado

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  getback Mon Sep 22, 2014 5:44 pm

Thanks JIM , I thought that was right but not sure Huh... ERic Very Happy were the controls as smooth as it looked I mean like the feel you get // Shocked ???
getback
getback
Top Poster
Top Poster

2022 Supporter

2023 Supporter

Posts : 10028
Join date : 2013-01-18
Age : 66
Location : julian , NC

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  JPvelo Mon Sep 22, 2014 7:12 pm

Eric,
Controls are very smooth and quick.

Jim
JPvelo
JPvelo
Diamond Member
Diamond Member

Posts : 1969
Join date : 2011-12-02
Age : 56
Location : Colorado

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  Theo Kleynhans Tue Sep 23, 2014 1:09 am

WOW Jim, that slab wing flies great. I am impressed with that performance.

Great job!

I will have to try this mod on one of my slab wing planes. Thank you for doing this and showing us all. This is a great forum!

Theo
Theo Kleynhans
Theo Kleynhans
Gold Member
Gold Member

Posts : 196
Join date : 2013-12-30
Age : 42
Location : South Africa

Back to top Go down

Modified 1/2a Skyray  - Page 2 Empty Re: Modified 1/2a Skyray

Post  Sponsored content


Sponsored content


Back to top Go down

Page 1 of 2 1, 2  Next

Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum