I know posting about 3D printed planes on here usually results in 50 comments of people saying "give me some cardboard and packing tape and i could build something better in an hour..." so I would like to preface this with saying that this was an academic exercise and the vision for the future is that you could upload your mission requirements to an interface, some software would design an airplane optimized for your mission, and then a printer would print it, all without a human in the loop. So, yes, I understand the practicality implications, but I think this is a very interesting exercise.

That being said... we finally got our plane to fly! The aircraft was designed by a group of students from Purdue University, Brigham-Young University, and Georgia Tech during the last academic year but it was never flown before the students graduated. An attempt was made but the motor ingested some gravel and blew neodymium chunks everywhere. I upgraded the propulsion system, modified the control surfaces (they used to be printed but they were very delicate) and that's about it. For this flight, I took out the ardupilot and just flew it manually.

Video of the flight here

All up weight with batteries was 12.000 lbs. Span is 8', and I can dig up area and wing loading and all that stuff. Flew it off 2 5S 5000mAh batteries ganged together to make 10S. 16x12 prop.'

Aircraft is almost entirely FDM, made on a fortus machine. There is a carbon fiber spar running down the wing and the control surfaces are foam. Other than that, everything you see is ABS.

Very wiggly in yaw, which was surprising as the scale model we flew last year was fine. Could be the fancy winglet design.

As you can see from the video, the landing was on the hot side, but the structure held up impeccably. There are sacrificial landing skids that did their job and broke on impact and we can just pop new ones in to fly again.

All in all, I'm overjoyed it finally flew! It's been quite a few months since the last attempt.

Hi all! Just wanted to share a project I have been involved with since last September. I was the TA for a class of students at Purdue University and we collaborated with students from Brigham Young University and Georgia Tech to create an almost entirely additive manufactured UAV for agricultural surveying. Boeing funded the program through their education wing and Stratasys was a huuuuuuuuuuuuuge help with printing our aircraft. 

Wingspan is 89" from winglet to winglet and we are running an APM 2.6 with all the fixings as our autopilot. We are going to be flying the model in a few days but we have flown a 75% scale foam and fiberglass version and gotten all the waypoint navigation working. 

Here is a top-down view of the aircraft. It is a blended wing body done almost entirely in FDM except for a small carbon spar and some hardware (hinges, nuts, bolts, etc)

Here is a cutaway schematic view of what the guts look like.

Even though we are heavier than anticipated (and what university aircraft doesn't have weight problems?), we are still around 12 lbs which is not bad for the amount of ABS we used. 

We have an NDVI generating camera on board so hopefully we should be able to start spitting out some good data soon. 

This project has really made us think about the value proposition that 3D printing poses. The other teams that were building aircraft at the same time went with more traditional composite layups and made gorgeous aircraft but they took forever to create all the plugs and molds and do the layup and assembly. Their airframes are much more robust than ours and can really take a beating but the amount of time sunk into fabrication is really thought provoking. 

Look for a flight video in a couple weeks! I'll try to put together some more info if people are interested. 

Finally getting around to posting a project I worked on a year ago at MIT Lincoln Laboratory. We 3D printed (FDM on a Fortus 400mc) a UAV with telescoping wings. Structure was primarily FDM except for a carbon fiber backbone that all the parts were attached to. Designed to be highly modular, the aircraft was essentially 3 reconfigurable pieces: the fuselage pod on the front with the avionics and batteries, the wings, and the empennage. To adjust the CG for different payloads you could move all the parts around until you balanced and had the stability margin you needed. 

We printed the wings without support material and with an internal structure that made them pretty strong. We also decided to incorporate carbon fiber spars into the wings which essentially doubled our strength to weight and it took less than a minute to install. Combining COTS materials with FDM really helped alleviate some of the strength concerns we had.

I've attached a talk that my coworker and I did at the RAPID additive manufacturing conference this year which has some of our lessons learned and more information about our aircraft. Hope there is something helpful in there for anyone interested in doing FDM UAV design! RAPID Presentation

I just designed and printed this. It snaps together in a few seconds and provides a good way for me to keep my radio pointed vertically. Seems very stable even with the longer antenna. You can find it on thingiverse if you want to print one for yourself Check it out here.

First of all, sorry for the unexciting video. Waiting on my new gopro so I made do with an old keychain cam. 

Flight went well! I was very impressed with the RTL performance straight out of the box. The Radian displayed much less of a tendency to wander than the 6' Telemaster I had flown with APM before. I will take a stab at tweaking the gains. This first image is just the RTL flight and the next one is all the flight data. 

Before landing, the plane didn't want to come out of RTL mode, so a lot of frantic switch-toggling happened and eventually it came back. Not sure what the issue was.On the plane,  I have the auxiliary antenna set up orthogonal to the main RX on board so antenna nulls shouldn't have been an issue....

Like I said, onboard video isn't great. RTL starts at about 2:17. 

All in all, not a bad morning!

Set up with airspeed sensor and telemetry. A little worried about propwash on the pitot-static probe but we'll have to see! 

APM frame is 3D printed and uses nylon standoffs to space everything out. Flight battery is under there but balancing leads exit on the right side of the fuselage so it can be charged and remain inside. Its also wired up to a switch so there's no more fussing with battery connectors. Battery was moved aft to counteract extra weight up front. CG is pretty dead on. 

I can post STLs of my frame if anyone is interested. It's stuck onto the fuselage with VHB. Hopefully will get some good video soon!