FTFC’25 MS Design SR - 71 Blackbird by Houndpup Rc

[Houndpup Rc]

any suggestions for the wing?

 

[Mr Man]

any suggestions for the wing?

As in?

 

[Houndpup Rc]

As in?

Like how much of an air foil i should have. Or any other ideas or cautions you guys have.

 

[Houndpup Rc]

Like how much of an air foil i should have. Or any other ideas or cautions you guys have.

This is fun!

 

[Mr Man]

Like how much of an air foil i should have. Or any other ideas or cautions you guys have.

Thicker near the middle and very thin near the tips. Try to minimize drag of course. (Should be easy with the blackbird)

 

[Houndpup Rc]

Does anyone have a blueprint for the back of this?

 

[Houndpup Rc]

Thicker near the middle and very thin near the tips. Try to minimize drag of course. (Should be easy with the blackbird)

I meant like how thick of a spar. I am kinda thinking two thicknesses of foam.

 

[Houndpup Rc]

My current progress!

 

[Burnhard]

Post pictures please.

 

[Houndpup Rc]

Post pictures please.

Of?

 

[Jo's squadron]

My current progress!
View attachment 249483

Very nice. I like the ''spar'' in the middle of the fuse.

 

[Houndpup Rc]

Very nice. I like the ''spar'' in the middle of the fuse.

Thanks! It's got a long ways to go and I probably will get halfway thru and not like something and start over.

 

[Houndpup Rc]

I just hope it has enough lift......

 

[Houndpup Rc]

Hey @Mr Man is there a tool for measuring 3D objects in Onshape?

 

[Mr Man]

Hey @Mr Man is there a tool for measuring 3D objects in Onshape?

I normally just create a sketch and make a line and measure it using the dimension tool.

 

[Houndpup Rc]

I normally just create a sketch and make a line and measure it using the dimension tool.

Okay thanks!
And how do you get the skins to loft out side your former and to be hollow?

 

[Houndpup Rc]

This is what happens right now when I loft

 

[Mr Man]

Okay thanks!
And how do you get the skins to loft out side your former and to be hollow?

First you use the shell tool to hollow it out, then the thicken tool to well… Thicken it.

 

[Mr Man]

I meant like how thick of a spar. I am kinda thinking two thicknesses of foam.

Yup, I’d say that’s a good thickness.

 

[L Edge]

Houndpup;

Advice:
You talked about using motors/prop also, did you see the review of this version of a SR-71. He talks about about stall condition for low speed so be aware of this condition. It ain't successful until it lands as a SR-71.
I hope you strengthen the wing including the outer segment past the ducting. It could fold in a sharp turn.
What are you using for foamboard?


When you launch, make sure you AOA is not to high or you will flip it. Add differential thrust so you have coordinated turns. You will need it.