raydar

Aussie you convinced me on the k30/avanti combo, as you know I have a couple k30's and put one in foam. Never fancied this airframe due to retract woes on grass and short fields but lately getting reports (local dealer just put one together) of k30 and avanti coming in at 3.3kg dry with jp gear upgrade. At 1400mm ish wingspan that is bang on the money for my local grass fields and flying skills. X45 sitting here to so of it lacks (won't for me) have a plan b.

Aussie1

Yes , we do seem to follow the same path regarding micro turbines. Interestingly enough, my favorite jets are both fibreglass construction being the Avanti/K30 and the Savex L39/K45. The K45 for me is the game changer due to its power/weight ratio.

1moparman1

My Feedback: (28)

LewisE1

caliber90

My X45 powered Avanti has done over 20 flights, so far very good.

I don't know what "standard servos" you refer to. I put Futaba HV servos in my avanti. I use 2 Optipower LiPo 1450 2S packs, one for radio, another one for turbine. I am looking to try 850 2S packs to make it lighter, since my Avanti consumes <200mAH each per flight.

My planes take-off and landing on asphalt so I can't comment on the struts off grass. The standard retracts has stiffer spring rate compared to JP upgrade struts. With standard struts in a hard landing always results in bending the pins in the struts ( which is good because they take the shock load, and second, it is easy to replace the pins), but a harder landing will damage the wood structure in the wings. My Mini Avanti are all replaced with the JP upgrade struts, which have softer spring rate, more effective in absorbing shock loads.

LewisE1

Aussie1

Hi guys, Iv'e had a few flights with the X45 engine, and it is much nicer to fly with the lighter X45 engine! I think that the jet lost 1.2kgs in TOW for the same engine thrust. Here is a hatcam video that gives you an idea of the performance.

why_fly_high

My Feedback: (19)

That much weight would make a huge difference. What else did you do to reduce weight. Taking the k45 out completely would not make up that weight difference.

Aussie1

Smaller batteries and a huge difference between the two engines, plus a small amount of lead was removed that wasn't needed. I think that you may agree that the performance is outstanding!

caliber90

Nice flight and nice field. What are the capacity of batteries on board?

Mine is with X45 and the performance is great, only that my TOW is no where near 4.2kg.

Aussie1

Yes, our club field is perfect for flying jets as the the runway was put in specifically for that purpose, and over the years, has hosted many National jet meets. The grass runway is also excellent, so certainly a asset to have. I use a 1200ma 2s 70c LiPo for the ECU and a 1400ma 3s for the RX. Looking at the turbine comparison chart in RC Jet magazine, the weight of a K45 versus a P20 with 5 minutes fuel is about 1kg versus 1.9kg. The X45 is slightly lighter than the P20, so yet another small weight saving, plus my juice bottle tank is very light. Changing to a light single wall pipe, removing lead and using small batteries has resulted in a very light jet. The weight explanation was for Why Fly High, but the X45/ Mini Avanti is indeed a perfect small turbine jet combination. My other X45 is in a Savex L39, and it flies just as nice as the Avanti!

caliber90

Thanks for sharing.

I use 1450 2S LiPo for both Rx and turbine. Both consume less than 200mAh each flight, with the one for turbine consumes slightly less. I was wondering why not combine the 2 into 1 battery for both?

Another question is what clunk you are using in the tank that is reliable enough to get rid of the UAT?

I have 2 flights yesterday with my X45 powered Mini Avanti. First was good as usual. The second one had flame out at around 1 minute after take off. No white smoke trail from the tail and at ground check, no bubble found in the fuel line. I then did full throttle test and a few taxi run, no abnormal sign found. the Accel and decal has been set to SLOW when I first got the engine. I did not enable the auto restart feature. Don't know how to further diagnose the problem.

Aussie1

Not sure why you had a flameout, but I don't use a trap tank, especially on the micro turbines. They only sip fuel, but I use a Honda felt clunk from a brush cutter, and try to minimize the use of Festo fittings. Touch wood, but have never had a flameout with the X45! I prefer two batteries, as I can monitor consumption from two seperate systems, so maybe that gives me a bit of redundancy. As a Airline Pilot, I guess I'm used to always having at least two seperate systems for everything!

Rich Few

Hi Guys
To save me trawling through this thread, what is the consensus on the best fuel tank and thrust tube for the X45 in the Avanti. Not wanting to spend on a composite tank !
I have the engine on order and converting mine from EDF.
Thanks, Richard

Aussie1

I use a one litre juice bottle tank and it's good for 8-10 minutes. My tube is a Grummania 50mm pipe and it seems to be perfect. I posted a video earlier and I guess that it gives you a idea of how it goes. Pretty impressive setup and definitely one of my favorite jets!!

Rich Few

Thanks Aussie, seen your video and very impressive. Might go the bottle route for the tank. Is your pipe single or double wall ?

Ian Rowe

Aussie1

This pipe is for a P20/K30 which is what I originally had in my Avanti before I put my K45 big can engine in it. It flew very well with the old K45 but was quite heavy. I then fitted my new X45 into it, losing almost 30% of it's total weight for the same power output, making it the perfect combination! The 50mm Grummania pipe is the same as the smaller K30 pipe by having only dual wall in the rear because of critical stab install area and of course, the fin. These pics show the K30 pipe, for comparison, and were designed especially for the Sebart Avanti. The Freewing foam Avanti doesn't need dual wall because you can line the duct with aluminium tape.

K30 size pipe

Helijet

Seems the kit has been sold out everwhere for some time. Anyone know when the next production run might be available?

thx
dw

siclick33

Helijet

I suspect your right.
Thanks for the info!

Dean W.

BarracudaHockey

My Feedback: (11)

SebArt USA either has or is soon getting stock in the US

ltc

My Feedback: (3)

Is that a custom pipe from Grumania?
I looked at all the pipes they offer for the Mini Avanti S across several turbine sizes and none of them look like yours
Did you modify one of their stock pipes or was this a new one that isn't on their website for the X45?
Any info would be appreciated.

Aussie1

This pipe is nearly 10 years old and was the standard pipe supplied with the P20 turbine conversion kit for the Avanti. The 45 size pipe is about 5 years old and was also what Grummania supplied at the time for the Avanti when upgrading to a Kingtech K45 or a Wren44. It was only dual wall in the critical area to keep weight down, and I have found that the 50mm pipe works perfectly with my X45. Looks like conversion kits may still be available.

https://www.dumfries-model-flying.co...conversion-kit

Rich Few

I looked at the conversion kit for a P20 but not sure if it would be suitable for the more powerful X45 !