DrScoles

My Feedback: (18)

Thanks Bob! I have a digital incidence meter/throw thing… can't find it. Good old fashioned distances make it much easier ;-)

No i-gyro on this plane.

Madiba73

Hi DrScoles

How did your Jet Weekend go? Did you manage to Maiden your Avanti Mini? Any video footage? Here is a video of the flight on my Avanti Mini after removing some excess weight and sorting brakes out. She still weighs around 4.8KG's fully fuelled but flies like a dream and needed no trimming after take off or even on full flaps when landing.

I did change my throws to those last recommend and they are perfect. Could do a little more on Full Flaps which I will try on my next flight.

Here is the video, not so great but a full video non the less. https://www.youtube.com/watch?v=-fktaQ9qaKg

ramonfun

Hello Madiba73. Could you please share a pic showing turbine and pipe? I am installing a wren44 and bought the pipe from grumania (the one for mini avanti and wren44), but I am guessing that I may need to cut the bell a bit aswell. Still have to figure it out with my local dealer so a pic of yours would help.

Thanks.

Madiba73

ramonfun

Wow!!! Great job Madiba73, and very helpfull for me. Thank you very much. This is funny, wren44 and the pipe are sitting next to the plane waiting for some free time for its installation, can´t wait...

Thanks.

Madiba73

Hi,

Here is latest Video from this Sunday: https://www.youtube.com/watch?v=X-EEn-4rAPY

Regarding the Wren you might find out shortly that they have gone under liquidation. I got worried yesterday as I had paid for a new Turbo Prop engine for my PC21 and have a whole lot of Wren 44 Heli Turbines that would need backup.

I have this morning got in touch with Mike who was one of the engineers at Wren whom together with Leonie in accounts have opened Wren Power Systems:

http://wrenpowersystems.com/

They have raised funds and have continued with the business under a different name. The orders are all being honoured by them and they will provide backup for anything from the last 15 years.

https://www.youtube.com/watch?v=3CqOGhUTQRk

Cheers and post some pics when you done with yours.




Here is a sepearet video of the Wren 44 JR Vibe 90SG with 3 blade MBL391 Head.

ramonfun

So that is why I could not find the Wren web site last monday. I was afraid of something happening to the company and not getting the backup service, I paid the turbine last week so you can imagine I was afraid of. So, very glad that you provide some calm since I was not aware about the company changing its name, so thanks. Will share some pics when I get some time to build it, hoppefully I will have it ready in a month, very busy at work.

Thanks to share the videos, it looks like it flies very nice. I was afraid about heavy landings due to the extra weight but it seems to be controllable, just a little fast but not big deal.

DrScoles

My Feedback: (18)

Good to see one in the air!

We had 40mph gusts at our event! I stayed home and worked on the house. I feel like a broken record saying that "this will be the weekend" I'm going to a warbird event next weekend, they'll allow jets before and after event, I'm taking it with me!

Midas D.

Hi DrScoles,

Any news?

Cheers,

Ed

DrScoles

My Feedback: (18)

Finally got to fly this thing! First flight had a flame out on climb out. Had enough speed to turn around and make it back. So even with a full fuel load and no power, it came in just fine. Had some air just past the UAT that wasn't clearing. Went against the RCU gods and used a festo filter I had in my box, took it out. Two more flights, this thing rocks! with the K45, climbed straight up and didn't want to stop. The throws someone shared above were perfect.

The manual suggests a gyro, it flies like it has one in it... Knife edges without much coupling. Hate to beat up the term, but it feels like it's on rails. You don't need a gyro.

This is plane is a great size, and just felt really comfortable to fly. Landing was a no brainer. I did some full power straight passes and the wings managed to stay on. ;-). I didn't think it would be a problem, but not sure I would yank and bank at high speeds.

As I stated in my first post, this plane wasn't meant for the K45, but I think it is a good fit. This could be a great entry level jet for someone, or a fun sport plane for the more experienced who wants something to throw in the car and get some quick flights in. It could fit in the back of an suv or truck without taking apart.

five minute flight with 32 oz of fuel left the 10 oz tank just under half full.

Cons: I don't like that you have to retract the gear to get the wings off. I would have preferred U shaped cutouts in the fuse that allowed the wing to slide out with the gear retracted.

Some of the hardware is suspect for what the jet crowd is used to, but we are dealing with much smaller control surfaces, and a lot of people are flying them with stock hardware.

like its bigger brothers, it won't lay flat. Not a big deal, but would be easier to store and transport if it didn't have the full length spine on the bottom. A piece of foam rubber or a robart stand solves the problem.

Its a keeper :-)

LA jetguy

Mike.. Congratulations on maiden.. Glad you were able to land safely on the flame out..

Mine with K45 (Sr. # 005) will be ready in two weeks... I'm using Tam pipe with his 32 oz Kevlar tank and UAT with Tam struts wheels and brakes. Using. BVM eBrakes to supply the air for brakes.

Thinking of using one 3 cell Lipo with two castle BEC one set at 9.6 for turbine and the other at 8.0 for reciever ... Btw all servos are MKS HV

Can you share your final CG point and the throws on the surfaces...Thank you

David

Midas D.

Good to see the report DrScooles :-)Just put mine on order so now the long wait has begun ;-)Any flight vids?Cheers,Ed

DrScoles

My Feedback: (18)

David, with that much fuel, you are going to be taking off pretty nose heavy. I moved the turbine in front of the mounting rails for CG reasons and didn't have to add any lead and the batteries were in the stock location. If you use another 12 oz of fuel, maybe put the turbine in the original spot??? That's gonna give you a solid 8-9 minute flight unless you're at full throttle the whole time.

My weight combination had zero weird tendencies. Took off smooth and predictable and was a piece of cake to land. I'll get throws and CG for you this weekend.

Sorry no vids.

LA jetguy

Thanks Mike... wait to hear from you..

ramonfun

Congrats Mike for your maiden. Mine will hopefully be ready in two weeks, so your throws and CG are very welcome here aswell. I am installing a 950 mL tank and 150 mL hopper. Guess that your tank is the same volume, mine does not sit at the CG but a little forward, what about yours? is your tank right at CG or it is a little bit forward aswell?

ramonfun

What about the wings fixing system? I would appreciate someone opinion and this part, I refer to the screw int the carbon bar, will it be enough taking into account the extra power that we have chosen? Has somebody thought about installing an extra screw making another hole in the wing? I am not sure if this is a good idea since it could modify the carbon bar propierties.

Finishing the test turbine stand this weekend, test next week and from there to the plane. Will share some pics soon opefully.

Allready installed HK electric brakes, will see how they perform, they are quite heavy 110 gr each. Glad to know that Mike landed propperly with the tank full since I am a bit worried about the total weight resulting in heavy landings.

DrScoles

My Feedback: (18)

Here are my throws. This is on three flights, and the aileron might still be a bit sensitive. Flaps and crow were perfect. I put the CG exactly as recommended. With the K45 just forward of the stock mounting rails, zero lead was needed and I could put the two batteries right where they were supposed to go. WIth the nose gear door servos so far forward, it would be hard to put batts that far into the nose. So I think turbine placement is pretty important for proper CG

I did bend back the struts a bit on my dead stick. I landed just off the runway in the weeds, took quite a few of them out, but the gear held. :-)
Didn't even realize it until I was breaking the plane down to put it away.

ail 1/2" ---still may be too sensitive
Rud 1 1/8"
elev 1/2"
flap 1 3/8" and 1/4"up crow

ramonfun

Thanks Dr. Scoles,
What about the mixings? Does any of you have mixed the elevator with flaps, or ailerons with rudder?

I test the turbine yesterday in a bench, very very excited since it was the first time for me starting a real turbine. Everything went perfect, amazing... I was even shaking.

Hopefully next Sunday will be the maiden, not sure yet, if I am able to finish it next saturday.

Thanks.

ltc

My Feedback: (3)

DrScoles,
when you mentioned that this might be a good entry level jet, with the K45 does it meet the minimum weight requirement for AMA turbine waiver (12lbs dry IIRC?)

http://www.modelaircraft.org/files/510-a.pdf

DrScoles

My Feedback: (18)

Wow,that is an interesting question. No it does not weigh 12 pounds. I have a feeling when that rule was written, smaller turbines didn't exist. I'd be shocked if anyone would give you static on that. If they do, they need to get a life…. This isn't a kite like a boomerang, or those hideous fixed gear wood planes (can't recall name and sorry if you think they are attractive) If you are not a beginner pilot, I think this is a perfect entry level plane. It takes off and lands very easily, and fly's like it has a gyro in it.

Knife edge it does veer away or towards you, I prefer to mix that out in my head. I have to double check if I put down trim with the flaps. I'm flying this weekend, I'll look and report back.

ltc

My Feedback: (3)

Actually, the latest AMA turbine waiver application and rules still state 12lb dry minimum, so perhaps the two turbine pilots (one of which is a CD) who are responsible for the sign off would overlook it, I'm not sure, which is why I asked.

I believe the fixed gear turbine trainer you referred to was the TBM Shockjet?
https://www.troybuiltmodels.com/news...f/shockjet.pdf

ramonfun

Hi DrScoles, did you get a chance to check if you added any flap to elevator mix? I have this mix in my habu 32x and it remains completely horizontal when I put the flaps, I guess that this will be required at the avanti aswell.

Mine is already finished (just a couple of details left), I may maiden next weekend if possible. There is an heli event th whole weekend in my club, not the best weekend for a maiden.

Will share some pics when I finish it completely.

Thanks.

DrScoles

My Feedback: (18)

Got a few more flights in on Sunday. yes, I would put some down elevator in for the flap setting. I didn't have it and I had to drive it down the whole time. Still lands super easy, just be better with 2-3mm of down trim. I had my son out with me and didn't have time between flights to sit down and program it in.

The stock landing gear literally fell apart I'm afraid. The nose gear collapsed and the pins out of the mains were lost… I put Tam's struts on, and all seems OK.

Love this plane! Effortless to fly well.

c_makhija

Hi Dr Scoles,

So you are using the stock retracts with tams struts?

thanks
Chatty.

DrScoles

My Feedback: (18)

Yes. To be fair to the stock ones, I ran the through the weeds on the first flight when it flamed out. But they're just not up to par in my eyes. Little phillips screws that worked themselves out and pins that popped out after just a few flights. Honestly, straight piano wire with the curly Q thing up top would be fine. But people might not think thats cool enough ;-)