Bird Of Time conversion

[Robster]

Help please....Thirty yrs in RC but brand new to electric powered planes..

Am doing an electric conversion on a Dynaflight Bird of Time 118" w/s...60 ounces.

I've had some components kicking around the shop for a few years and am wondering how The BOT will perform if i were to use them....I have at hand a Mega 22/20/4 brushless motor... a Castle Creations 45 amp ESC..and planned to use with a 3 cell 11.1v 1300mah (14.42 Wh) Lipo battery all being pulled with a 10/6 prop

Whats this 3 meter bird gonna do at launch..

(1) Creak/groan slowly upwards, hanging on the prop at stall point ?
(2) Climb with authority
(3) Streak straight up and outta sight in 6 seconds

Thanx

[gramps2161]

Here is a link to the BOT might help you out with yours. I also moved your question to this area hi-performance and sailplanes.
link to the BOT
http://www.wattflyer.com/forums/showthread.php?t=3234

[Leadchucker]

It'll fly on your power plant but you will definitely be in Catagory 1. To get mine to Cat 2 (climb with authority) I wound up with a Rimfire 35-48-1300 running at 700 watts with a 12x7 Aeronaut. A 1300 maH battery is too small for two reasons. One being you're going to need ballast to achive proper CG so why use lead instead? The other is to feed a bigger motor as the 400 watts you have now will probably be disappointing.

Even with the bigger Rimfire motor ,80 amp CC ESC and a 2250 maH 3S lipo in mine, she still needed 4 oz of lead to balance. Weight was 65 oz with full gear of 4 servos,Rx and the above power plant.

Do plan on cutting in spoilers, you'll be glad you did. The BOT floats in ground effect forever and the spoilers are nice to get out of trash mover lift. Try to use the lightest servo that you can if you do the stock intstall in the tail. You don't need tons of power with the balanced flying stab. Or do the mod and put the rudder servo forward with the elevator servo and use the bell crank setup in the tail.

[Robster]

Thanks LC for the power suggestion...I'd been reading about spoiler installation and the problems some appear to have trying to get this bird down in a root puller..... was considering HK servoless ...or should I lay out the extra bucks and go Graupner ?

[Leadchucker]

Robster,
I just went simple with the spoilers.Cutting them in is easy as heck, I used a piece of 1/4" x 1" trailing edge stock and made hinges from Mono Kote then ironed them on. No need to big big either, 1" x 9" works very well,the servos are HS-55's and are plenty of power. She drops like a brick when they are deployed. See pics. And yes, I striped and recovered her as I didn't the creamsicle covering livery.p

Warren

[Robster]

Originally Posted by Leadchucker

Robster,
I just went simple with the spoilers.Cutting them in is easy as heck, I used a piece of 1/4" x 1" trailing edge stock and made hinges from Mono Kote then ironed them on. No need to big big either, 1" x 9" works very well,the servos are HS-55's and are plenty of power. She drops like a brick when they are deployed. See pics. And yes, I striped and recovered her as I didn't the creamsicle covering livery.p

Warren

Yay Warren....Bingo........ simplicity itself, no linkage to bind, weighted to simply fall down under gravity and wind pressure to flush position........Superb idea, I'm gonna install those, fer sure

Thanx
Rob

[Leadchucker]

Robster,
I had to find the photo I was looking to show you an optional way of spoiler retratction without linkage. Here's a pic of the spoiler setup on my 3.2 metre Pulsar. It's still simple and works. You can get away with the weights and they work fine as there is no centrifugal force that could open the spoilers on launch as there is with a winch.
Rubberband placement this way puts minimal stress on the servo at open position but still gives positive closure.

[Robster]

Originally Posted by Leadchucker

Robster,
I had to find the photo I was looking to show you an optional way of spoiler retratction without linkage. Here's a pic of the spoiler setup on my 3.2 metre Pulsar. It's still simple and works. You can get away with the weights and they work fine as there is no centrifugal force that could open the spoilers on launch as there is with a winch.
Rubberband placement this way puts minimal stress on the servo at open position but still gives positive closure.

Have you ever tried using those small dental quality silicone rubber bands, they are used for holding dental orthodontics/braces in place....they tend to be lighter gauge elastic, more resiliant and seem to generally outlast regular rubber bands by a mile.

[FlyWheel]

I like the open look of those spoilers, but how strong are they?

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[Yakfishingfool]

Hey Lead, I love the Bird of Time, seriously thinking that may be the next bench project. Would love to get together and fly some time. Scott