Decided on 60cc aircraft expressly designed for electric flight

[Andrew767]

Adrian

Can i just say...I don't post very often but i have really,really enjoyed this thread. I would never build or fly anything quite so big as this but nevertheless it has been a real learning curve.Sorry about the stupid question about RXs and carbon fibre earlier (i know nothing about airframes with C/F) but otherwise fantastic!!...Thank you for posting this and i'm glad all went well...

Andrew

[john stones 1 - Moderator]

Well done Adrian, nice trailer.

[Nigel R]

Great stuff.

Nice site too!

[Adrian Smith 1]

Thanks Andrew767, not a problem. Enjoyment is not based on size, design or discipline alone, more a case of what you enjoy. This plane appears to be so aerodynamically clean that it may not appeal to the purist, but as I say it's all about what appeals. I still have a little 60" leccy MXS which is just as much fun. Glad you liked the thread.

Thanks John & Nigel. I won't feel I have finished the job properly until I put a video clip on here, but the weather is pants for quite a few days! I think when I end my days I will be carted off in that trailer John!

[Adrian Smith 1]

Now I am a stupid dolt! I took the GoPro out today when flying the Extra. What I did was to only put a 1gb card in the camera in error! The end result was under 3 minutes of video clip. I will do it properly next time with bigger capacity card, but here is what I have. Ignore the old git at the start of it. This morning was cold and as you can see some ground haze was present as the sun got to work on the frost. I will video MORE at a later date.

**LINK**

Incidentally, The 2S RX lipo's (3600 mAh) closing voltage was reduced from 8.4v at the start to 8.0-8.1v at the finish after four 7 minute flights. Not sure what to expect with these HV brushless servos, but I was surprised at how little capacity was used.

Edited By Adrian Smith 1 on 11/12/2018 13:04:07

[Adrian Smith 1]

As promised a couple more videos. Both pretty similar. It was a windy day today 10 mph+ so a lot of the flying/tracking was imprecise. A lot of fun though!

**LINK**

**LINK**

Hope you get an idea of how good she is.

I did reduce the duration to 5 1/2 minutes given I was heavy on the throttle to avoid stalling in the moderate breeze. As can be seen I completely misjudged the first landing due to wind speed.

Edited By Adrian Smith 1 on 17/12/2018 20:06:17

[Dave Wilshere]

I have a CARF Hybrid Extra with four MacGregor 5921HV and 1 x 6928HV on rudder, I'm using a Powerbox Sensor Switch HV (so output 7.4v) with two 1000mAh Overlander Rx Li-Pos and I get three flights inc some 3-D.

DW

[Adrian Smith 1]

Good stuff Dave. Do you have a video clips of it?

[Dave Wilshere]

No, there was no camera the day I test flew it (3 weeks back) and I've not flown it since. Did you ever post your final weight? I was happy with mine, with 12s Overlander 45c 5000's its 8.42kg ready to fly. Flies light too!

Might not fly it again until its warm, I started the build back in May and finished it in Nov with other commitments!

Dave

[Adrian Smith 1]

The AUW was 8.48kg, Dave. I am also using 12S Overlander 45C 5000 mah. Also got some Turnigy 40-50c 5000s on a 12S set up. My prop is JXF 24x8. Given the aircraft is specifically an electric design, the performance is very good at that weight. Because she is light too, under normal circumstances, she is a doddle to land.

Adrian

[Dave Wilshere]

I have a set of Overlander 5800 35c packs, flying 6 1/2 mins on two sets of 45c 5000 and one on the 5800 35c gave me a very similar end voltage on each cell. It was not that warm and the packs were not warmed to 30 degrees for optimum discharge.

I have a Graupner 8028-190 motor since they had it on special and i'm running a Graupner Electric 22 x 10 at the moment. I have a 24 x 10 to experiment with when its warm again. On the 22 x 10 it prop hangs just above mid stick and punches out well.

Dave

[Adrian Smith 1]

Interesting, Dave. I have not tried any Graupner kit. Where do your source it from?

I am also testing out some 4-Max Purple Power ProfessionalV2 6000 mAh 40C packs in series (12S) in the Extra 330. I have conservatively timed the flights at 6 minutes before landing and she seems fine despite the extra weight penalty. End voltages on all the cells are around 3.78-3.80v across the board.

[Dave Wilshere]

From my shelves! I've been a main Graupner agent for over 20 years. Graupner did/do a 2.4m wood Extra 330 based on Gernot Bruckmann design, they recommend this motor and I built one for a customer and test flew it for him. It worked great, so when I got the Hybrid Extra from CARF I skipped the DLE 61 first thought and went electric since I have plenty of 6s packs from 90 size heli's and the motors were on a super cheap offer.

I'll do a better test once the temperature allows the cells an easier time. But I was finishing at 3.82ish after the 6.5 minute flights, with electric its a case of flying a schedule-high power stuff at the beginning of the flight and flat controline inverted circuits and alike at the end, like this the cells won't be 'stressed' as the voltage drops and you can eek out another 30secs on the end.

I have 6-9KW EDF models and you get used to coasting once you are 3/4 through the flight.

Dave

[Adrian Smith 1]

For the record another cracking flight just for pure pleasure.

here is a clip.

**LINK**