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-   -   "mirage 2000" (https://www.rcuniverse.com/forum/electric-rc-jets-198/11607260-mirage-2000-a.html)

jofro 11-28-2014 11:15 PM

"mirage 2000"
 
1 Attachment(s)
My highly modified foamy Mirage by FlyFly at its favoured flying field. Hotted up to 9S next to 7S powered Habu. Another flying day in paradise.http://www.rcuniverse.com/forum/atta...mentid=2050776

jofro 12-02-2014 11:58 PM

5 Attachment(s)
http://www.rcuniverse.com/forum/atta...mentid=2051835http://www.rcuniverse.com/forum/atta...mentid=2051836http://www.rcuniverse.com/forum/atta...mentid=2051837http://www.rcuniverse.com/forum/atta...mentid=2051838http://www.rcuniverse.com/forum/atta...mentid=2051839Few more pix of this unique build.

jofro 12-03-2014 10:57 PM

1 Attachment(s)
http://www.rcuniverse.com/forum/atta...mentid=2052048I'm changing efflux nozzles on all my jets, if it doesn't look better or more unique at least it improves my performance and makes the sound more silver-lish. Summer is finally here, lets do more flying!

jofro 12-10-2014 12:17 AM

2 Attachment(s)
http://www.rcuniverse.com/forum/atta...mentid=2053574http://www.rcuniverse.com/forum/atta...mentid=2053575Mirage has been working overtime, it's been long time being dead calm at the beach, another magic day and what a strip! Enjoy latest pix.

jofro 09-12-2015 11:48 PM

2 Attachment(s)
http://www.rcuniverse.com/forum/atta...mentid=2119586http://www.rcuniverse.com/forum/atta...mentid=2119587How the time flies when you having fun, 12 month since my last post, another hundred of flights added in the log, couple today in windy 90 deg. cross wind conditions, this model handling it with ease. How about the landing strip?

aeromax18 02-18-2016 02:10 PM

Could you elaborate on the nozzle change and improvement?
Thanks
Solly

jofro 02-18-2016 10:18 PM

It minimizes the efflux spiral turbulence.

aeromax18 02-21-2016 11:40 AM

Thanks Jofro
I enjoy your posts and videos. Great inspiration. I returned to RC after 30 years involvement with Experimental aircraft. lost my medical so I can't fly anymore. I'm about to finish a Foamy F16 that's 160 cm length and 100 cm span. I decided to glass it as practice for future builds but it added quite a bit of weight ( about 800 grams to the foam airframe) Total weight is now 2.7 kg. I need to choose some inexpensive servos for it.
In your opinion how much torque do I need from each servo if I place two for elevators and two for flaperons? would appreciate your help on this.
Thanks
Solly

jofro 02-21-2016 03:28 PM

Good to hear, I have been flying Starmax foamy F-16 for over 5 years now, its smaller at 145x 100cm runs 8S at 3.6kg AUW, (3.5kW). On lot of these models I use 1/2 size metal gear servos with 4-5kg torque. Linkage geometry is more important, I rather have shorter control arms to minimize the slack. 800g is lot of extra weight for small airframe, 2.7kg, is it only the frame or fitted with power unit ect.?

aeromax18 02-23-2016 11:45 AM

Jofro,
This is a profile F16. I had 5 cm(2 ") plates of XPS 50X120 cm. I had cut one with hot wire and created two 2.5 cm plates. Bonded them together to create the wing plate and used a 5cm to create the fuselage. I hollowed out a tunnel in the top fuse half to run the wires hidden in it. I'm using a 3248 NTM motor 815 W with 4s (5000 ma) . Total wt. is 2.7 kg. I had sanded the foam wing into an airfoil shape and glassed the whole thing over with a 125 grams of fiberglass cloth ( could not a 75 grams locally).

Initially I thought it would be a hand launch but now with this weight I figured a wing loading of 37 Oz. per sq.inch I am not sure. I need your advise on this. Should I attach a fixed landing gear to it?
for some reason I can not down load the pictures I took from my LG phone to the computer. I can mail a coupel of pics. on whatzup if you have an account.

We have great beaches here too (Netanya, Israel) but it's too cold now. I'm waiting for the summer in a couple of months.

Best Regards

jofro 02-23-2016 09:18 PM

Hi, I didn't realize you built it from scratch, I'm afraid your power won't be good enough at 2.7kg AUW. The loading you probly meant to say per sq. foot? I work metric which would translate to some 115g/dm2, that's pretty heavy for a small plane and no power. Forget about 4S, 6 would be more realistic but than again extra weight. I wouldn't worry about the l/gear at your weight. I suggest extend your wing tips by 3-4"each to reduce loading, that's what I do with overweight models, easy fix, I don't use whatzup. Cheers.

aeromax18 02-24-2016 08:25 AM

Jofro,
Thanks fro your help. I'm new to Electric so I used the recommended power to weight ratio of 150 W per 1 lb which indicated a 800W motor will be plenty of power but I tend to agree with you that it looks a bit under powered. I have a bigger motor 4248 600kv / 1200W which I'll use. with 5s
I also measured the wing area more accurately (seriously) and it is larger than I thought. the wing loading came to 86 gr per dm2. with wing extensions as you suggested it will reduce to 74 gr/dm2. sounds like a much more reasonable to handle thank the 115. I think I will go ahead with the extension since I haven't flew rc in 30 years.
I'll try to figure how to download the pics. and send some to you.
Thanks again Cheers

jofro 02-24-2016 03:52 PM

Hi, I would never rely on recommended or listed figures, most of my EDFs are 300-450W/lb. Jets are heavy hard ware, if you know what I mean. 75 grams loading sounds pretty good, just about loading of a nice pattern plane. It is your own build, so it's great idea to extend those w/tips if you can't reduce the weight. Make sure you get good cooling for your ESC and motor by adding heat sink to it if possible. Good luck with it. J.

aeromax18 02-25-2016 01:25 PM

2 Attachment(s)
some pictureshttp://www.rcuniverse.com/forum/atta...mentid=2149426http://www.rcuniverse.com/forum/atta...mentid=2149427

aeromax18 02-25-2016 01:39 PM

I think that the flying fuselage area will add to the total wing area by about 20%? I'm definitely adding wing extensions that I can saw off later on after some flying practice. It's first foamy so it's not very scale, Hahaaa. Esc and batt. are placed in that slot up front. Do you think they'll have enough air flowing around for cooling? Wires are hidden inside the fuse. Waiting on some servos to arrive. 4.5 kg.
Cheers

jofro 02-26-2016 02:05 PM

I didn't realize it is a pusher, post it in different Thread, this is EDF Forum. Never the less it should fly fine if you stream line your control's Trial edges, BTW, it was a waste of time to glass it with all the extra added weight. Enjoy having fun with it. J.

aeromax18 02-28-2016 01:39 AM

Yes I think it will fly fine. Thanks for your help and I'll start a thread elsewhere.
Cheers

jofro 02-29-2016 07:39 PM

1 Attachment(s)
http://www.rcuniverse.com/forum/atta...mentid=2150085Back to the subject, another perfect flying day burning some Watts, video nect.

jofro 03-01-2016 02:53 PM

No sign of wear after all these years, enjoy.
https://youtu.be/O10O8L3U9sc

Joseph Frost 05-01-2016 03:07 PM

Another action taking off the rugged air strip.
https://youtu.be/P_MN70nPF2w

Joseph Frost 07-17-2016 08:46 PM

1 Attachment(s)
Using my Mirage to brake in new set of lipos. Latest video.
https://youtu.be/aT7JzbqnCms

Joseph Frost 07-26-2016 02:47 PM

1 Attachment(s)
Latest spectacular video footage from my club.
https://youtu.be/j17KUMg9we8

Joseph Frost 08-15-2016 12:30 AM

My work horse Mirage at its best.
https://youtu.be/8LJOeamuEkQ

Joseph Frost 09-13-2016 11:57 PM

1 Attachment(s)
Latest footage with some shaky landing in windy conditions.
https://youtu.be/pQCDdUoPCcE

Joseph Frost 10-17-2016 11:12 PM

1 Attachment(s)
After 2 days of 60-70k wind today was just another perfect flying day, latest "Mirage" action, just noticed on top of fuse stress crack in the foam after all the hard work the model is going through, needs some attention.
Today's video footage. https://youtu.be/eL6RToUrvjg


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