Pushing the limits

While I have, for some time now, hinted at our intentions to obtain a more capable aircraft which will provide longer endurance and higher payload capacity, I have kept it mostly in the shadows. Well, it is now time for me to [very excitedly] announce the arrival of the newest and most capable addition to our fleet of aircraft: the Mugin v3 aircraft.

This impressive aircraft will launch us into a whole new class of UAV remote sensing, giving us capabilities far beyond our current stable of electric aircraft. Here are some of the details:

Wingspan:	3m
Material:	Wood structure, fiberglass and film covering
Powerplant:	Saito FG-57TS 57cc, 4-stroke, twin-cylinder, gas engine
Propeller:	Xoar Beechwood 22x10
Flight controller:	3DR Pixhawk
Cruise speed:	120 km/h
Endurance (expected):	~5 hours
Range (radio limited):	~100 km

This aircraft is not widely used, but there are some notable exceptions. CanberraUAV used an earlier version of the aircraft in the 2012 Outback Challenge. There are a handful of others who are discussing using it with APM/Pixhawk or are in the process of adopting it into a program, but we are certainly spring-boarding ourselves to the forefront of this work.

Stay tuned for updates on the build and testing of the aircraft. At the moment I have done the little bit of assembly that is required on the fuselage, gotten the motor and fuel system set up, and installed all the electronics. The next steps are to break in and tune the engine and power up the electronics, configure them, and test them out. The it will be flying time. As I have been building I have been looking around and found that there is an utter dearth of information about this airframe, so I will do my best to document the process in painstaking detail.

Too much excitement

Alright, after long absence I have some updates to make. First of all, to follow up on my last post, the endurance quad got back-burnered but we're going to turn our attention back to it. We made some test flights and determined that the vibration levels were too high for reliable flight. I traced this issue back to the motors, so we're replacing them. We could change bearings and fix the vibration issue but I already wanted to swap the motors for some lower KV ones, so I decided to save the time on the bearing work and just get the right motors for the setup. They should arrive in the next week or so, so I'll update once we have some flight time on the aircraft.

2 Zephyrs heading to Peru soon

Second, I have been in a build frenzy around here, with 3 Zephyrs just getting finished up and another right in the middle of the build. I am also working on a rail launcher that should get the planes in the air more reliably. It looks like we will have some fantastic weather this weekend, so we should be able to get all those new aircraft up and see how they perform. I'll provide more info on that after the weekend.

The Deacon Zeph in its fantastic black and gold livery

A bit of bad news is that we did a test flight on one of the new Zephyrs a week ago and had a crash on takeoff. We had flown it before and it performed really well, so that caught us by surprise. The wind was quite gusty and swirling on the ground that day so we think there might have been a stall issue with a rogue gust on takeoff that put it in the ground. We should be able to determine if that was the issue this weekend. I review the logs and there was a suspect board voltage change, but it didn't happen until after impact. We'll keep an eye on that to see if we actually have a hardware issue.

Finally, on the same day we crashed the Zephyr, we also did our first ever successful fully automatic airplane flights. We had tried auto-takeoff before with a skywalker and it ended badly. We were hoping that new firmware had solved all the issues we had before, so I put together an auto takeoff, circuit, and auto landing mission on Marcus' Pixhawk-equipped Apprentice. We were able to carry out the flights with total success from hand launch and ground roll despite the heavy winds (really too windy for an Apprentice). We found the results to be repeatable, with identical performance on numerous flights.

Well, thats all for now, but hopefully on Monday I will have lots of exciting updates to report.