IMAC Delro 2.5M Raven Build

[Wacobipe]

Interesting cowling design. So, the engine, etc has to be mounted while working through that opening?

Yep! It could definitely present some challenges depending on engine choice ( I wanted to put a DA70 in this bird but ended up going with a DA85 as it will actually fit better inside)...but the lines are so clean and the access is very open ( from underneath the airplane). Really like it overall...much better than a cowl that slides over the front of the fuse and has to be oversized in my mind.

I'll get some better pics of the opening so you get a better sense of the design.

 

[Wacobipe]

Nice build so far. I like composite planes. Someday I will pony up and buy one. Until then, I will drool over these build threads

I've always wanted to try one. It is definitely stretching my build knowledge but I am really liking it so far...and the end results should be awesome. Just imagine...no more covering wrinkles in the sun!

 

[Dooinit]

Yep! It could definitely present some challenges depending on engine choice ( I wanted to put a DA70 in this bird but ended up going with a DA85 as it will actually fit better inside)...but the lines are so clean and the access is very open ( from underneath the airplane). Really like it overall...much better than a cowl that slides over the front of the fuse and has to be oversized in my mind.

I'll get some better pics of the opening so you get a better sense of the design.

So are you going to run a re3. I want to try the 85 on a pipe in a 35%

 

[Jetpainter]

So are you going to run a re3. I want to try the 85 on a pipe in a 35%

I've flown a 35% Pilot extra with a DA85 and an RE3 many times. It makes tons of power, but the transition has never been great and it makes 3D more difficult. I'm trying to talk him into changing to a one of Planebenders smooth pipes to see if that helps. For IMAC style flying it's great. The 85 in Waco's Raven should be plenty strong, even without a pipe.

 

[Wacobipe]

So are you going to run a re3. I want to try the 85 on a pipe in a 35%

Nope...running a KS Canister

 

[MattyMatt]

A quick question for all you aerodynamic experts out there...the Raven comes with no directions... the wing main wing tube (spar) and rear anti-rotation pins are molded into the fuse (also the wing fairings are molded in so there is no adjustment on wing position) so placement is easy. The horizontal stab main tube location is molded in but the anti-rotation pin location is not. I am bout to propse my plan but want to hear from others an their thoughts for incidence of wing and tail...

My plan is to use the wing incidence as the datum (master measurement). My plan it so set the wing at a positive 0.5 degree of incidence (counters gravity)...and from that have the horizontal stab and the engine crankshaft each at 0.0 degree incidence. In other words, the fuse, engine, and tail will be at ZERO incidence angle with the wing at a Positive (upward) 0.5 degrees of incidence.

Note there will be a right leaning angle to the motor to counter torque...this angle is molded into the cowl where it meets the spinner.

My understanding is this setup gives you the upward lift needed to support the plane (symmetrical wing) and doing so at the wing (CG) means throttle changes don't change the pitch. Alternately, setting the wing at zero and the tail at a positive (or using elevator trim to accomplish the same) changes with every throttle setting.

Thoughts everyone?

This really depends on several factors. Speed, how nose heavy you want the plane to be and ultimately to remove pitch coupling. I have positive in my dalton. For my Delro 3.1m Raven, it's set where Delro set it up, and can tell you that it is the truest flying Giant Scale planes I've flown. (I've flown a lot). I think I have 2 and 2.5% pitch mix.

For example most great imac planes (Dalton & Carden) usually need 6-9%.

Leave it alone. These are amazing planes designed very well... Don't over think it.

 

[Jlc]

How's your plane coming along? I was making good progress on mine then I broke my arm so things came to a halt. Of course it was my right hand.

 

[Wacobipe]

I was cruisin' along and My Dad Passed away this past Wednesday. Just got back home but I don't fell much like building, and I have to travel for work this coming week so no idea when I'll get back into it...the DA 85 for it came this week while I was away so that was a nice box to come home to!

 

[Jlc]

I was cruisin' along and My Dad Passed away this past Wednesday. Just got back home but I don't fell much like building, and I have to travel for work this coming week so no idea when I'll get back into it...the DA 85 for it came this week while I was away so that was a nice box to come home to!

Very sorry to hear about your dad.

 

[Pistolera]

Oh wow....really very sorry to hear. Lost my Dad 5 years ago, but still seems like yesterday.