kimhey

I have had this model in my shop for some time, and while waiting for my AERO L29 from Air-C-Race, I decided to complete my Mirage I pull out the Jetcat P20sx from my HABU32 which have had many successful flights.

I am close to finishing, but can´t decide whether to go with or without rudder control... probably won´t use it anyways. The kit comes without gear doors for the mains, so I made some from GF/CF and resin.

As now, AUW is a few grams short of 3 kg (6,6lbs) with a whopping 600ml of fuel + the small UAT. The tank I am using, is custom made by Marc (GBRjet) for the Habu32, but fits nicely in the Mirage.

Maiden flight will be in stock gray, with colourful markings taped on for better orientation

If it flies well, I can start finding a nice scheme



Kim

bidrseed2

My Feedback: (2)

Good luck!
My mirage is slightly heavier than yours.
Getting it to rotate can be a problem. I had to lengthen the nose gear to give a positive angle on the ground.
I also had to tilt the main gear forward, as th wheels are behind the CG. But it looks like you have that covered in the photos.
Make sure you have all the elevator Travel you can get.
I'm away from home right now otherwise I'd give you exact figures and my CG
Best of luck.

Dave Wilshere

Kim

I test flew Frank's Mirage, plenty of Expo on ailerons and little on elevator . Also with your ECU position don't fly on wet runways, the nose wheel will throw water on it!

Dave

kimhey

@Bidrseed2, Thanks for the info. I will appreciate if you get a chance to check your CG. Can you recall if it differed much from the manual´s recommendation?

Did you modify for rudder control?


@ Dave, good catch I am planning to make a "cage" attached to the cockpit floor, to reduce/minimize water from entering the electronics area...

bidrseed2

My Feedback: (2)

Ok,
Home on wednesday ( In case anyone wants to break in in the meantime), Ill measure the CG then, and the control throws, dual rates etc that im flying with.

I did install a rudder.
Its not very useful, but good to have when youre flying slow with a high angle of attack. Not sure id bother fitting it just for that though.
The take off roll is very long though, so it does come in useful on the ground. But my example weighs 8 lbs wet, so if you are lighter and your takeoff roll shorter, you may be okay.

If i was you, Id try without and how quickly you get airborne would determine if you needed one.

kimhey

Thank you so much

I am at 6.6lbs wet, and I have a positive attitide on the model on three wheels. Maybe I can reduce takeoff roll compared to you, but we do have 300m of asphalt rwy...if thats not enough, this model will go of the rwy at a scaringly high speed[X(]....

I am greatful if I can copy your CG/throws

I am still pondering about the rudder.....



Kim

xxq111

http://www.youtube.com/watch?v=V3wUGIApOkQ

http://www.rc-network.de/forum/showt...FCr-JetCat-P20

Regards
Sejenssen

bidrseed2

My Feedback: (2)

http://m.youtube.com/watch?v=cblPhji4xqM

Takeoff's around the 2 minute mark

CG & throws to follow.

kimhey

Great! I have been searching Youtube to find videos of this model, but this last video was new to me

Thanks!

speed is life

Hi Kim, my HT/JetArrows Mirage is high power 90mm EDF, 8lbs all up RTF, no changes to the CG from the instructions it is spot on as is.
My aileron throws are +/-6mm, elevators are dual rate: +17mm/-10mm takeoff & landing, +/- 8mm high speed flight, throws measured from the inboard trailing edge. You will need all that elevator throw for take off and slow speed approach/landing high alpha.
no rudder and not really needed.
The problem with long takeoff roll as I see it with mine is not ground stance (I have positive angle as well) but a scale main gear location which is really too far aft of the CG. This makes rotation very difficult at lower speeds due to the downforce needing to be achieved by the elevators to overcome the moment arm. Mine has to run probably 125-150 meters to rotate for takeoff.
Trim for takeoff is about 4mm up elevator as measured at the inboard trailing edge and you have to pull nearly full up to get it to rotate.

kimhey

Thank you speed_is_life. Very useful info for me

kimhey

Got a chance to maiden the Mirage today, and with a great result. Thank you all for inputs in this thread

I had 20mm up elevator on high rate, but needed only half stick to rotate after less than 100m. Flipped the switch to low rate (10mm up/down 30% expo) and left it there for the rest of the flight. Ailerons were also quickly set to low rate (6mm up/down 35% expo).

2,5 kg of thrust on a 3kg model is more than adequate. I only had full power on take off, one high speed run and a couple of verticals. The rest was at just above mid stick.

My feet were getting cold ... (winter in Norway), so I decided to land. I kept a slighty positive incidence, and the Mirage slowed down nicely and stuck to the runway at first touch down.The flight lasted just over 4 minutes, with 50% fuel left in the tank.

CG was according to the manual, but I think it might be a tad nose heavy now (my measuring might be a bit off). I will fly it more before shifting it backwards.

I did not care to paint the model before maiden (I seldom do), but covered the model with yellow solartrim to get some sort of visual orientation in the air. The model is small as we know, but can also be flown inside a small envelope if speed is reduced. Control authority were good at lower speeds.

How it looks now in temporary markings:

Bob_B

My Feedback: (11)

Congrats on the maiden

Delfin29

Hi Kim.... Do you still have the HT Mirage?
I'm looking at one at the moment and wondered if you can give me some more info on flying characteristics etc...
You mentioned previously your AUW was 6.6lbs... can you tell me how you achieved this weight i.e. can you give me a kit list of your components...
-Tank size?
-Retracts Air or Electric and which brand for legs oleos wheels and tires?
It seems there are a number of different flying weights out there and although this is a delta and should be fairly stable and benign in the stall, I would like to keep it as light as possible...
I fly EDF at the moment s this would be a first turbine model...
If you do still have it and fly it... It would be interesting to hear how you have set it all up now...
Thanks in advance.

kimhey

Sorry, I sold it almost a year ago. I enjoyed it alot, but after some weeks, it was always left at home when I went flying...I prefere my bigger jets.

I can not recall paying special attention to weight saving, so you should have no problem achieving the same auw as I did. Retracts were taken from my Habu32, I think they are called Eflite 25? I don't recall what struts I used. Servos were Futaba 3150.

This Mirage is a sweet flying model, and I flew it with the same setup as on maiden, on the following flights before I sold it.