this morning at 7.30AM (geez, i didn't even have my coffee at that time! ) we maidened the mini bandit. Bruce deVisser was so kind and helped me out with his expert advice and his bungee.

i calculated the CG with that 25%/33% rule and first flight was with a 7x600AE pack - an awesome AUW of 14.5oz.! the fan unit still vibrated like crazy, even with the nice rotor mod from dave morris. whatever, i was too curious and wanted to see if this thing flies...

<a href="http://www.feiermehl.com/rc/images/bandit_maiden_1.jpg"><img src="http://www.feiermehl.com/rc/images/bandit_maiden_1_tn.jpg"></a>

first launch: the bandit went off the bungee like crazy, but once it slowed down after the launch i saw there was not enough ooomph from the fan to keep the jet flying zippy. also the elevator trimming was too much up. so the jet climbed every time it gained speed, then slowed down and began to stall. so i flew it like this from one stall to another and brought it down safely after ~2 minutes. at least Bruce caught some time to make an inflight picture.

second launch: we decided to move the CG back a little and used a lighter NiMH battery pack this time. but the enormous acceleration of the bungee shot the pack from its front position all the way to the back and this messed up the CG during the launch. the plane just dropped like a dead bird directly after launch, but nothing broken. well, "a little less bungee next time."

third launch: lawn dart! two ticks down trim were apparently too much, so the bandit digged its nose with high speed into the lawn. one wing side ripped of the fuse, repairable.

<a href="http://www.feiermehl.com/rc/images/bandit_maiden_2.jpg"><img src="http://www.feiermehl.com/rc/images/bandit_maiden_2_tn.jpg"></a>

bottom line: it was fun and i am happy that it was in the air at least once, my first stick time with a jet. but several problems/variables like the CG position, fan vibrations->too little power, too high AUW, and the trimming, let the mini bandit be far away from a "zippy flying jet". there's still a lot of work/experimenting to do.

i appreciate every input for improvements.

_Jens

Jens, Your jet looks really good. I like the color scheme. You'll have to tell me how you mounted the wing. I hope it is not damaged too badly. Will you have it out this weekend? I am starting work on the A-7 real soon.

you would like to try it with my BL02012t? if you can get the CG worked out and just need more power I will be happy to loan it to you to try. It would be best if you could squeeze in a 8 cell 600ae pack, I have a 2 sticks of 4 your welcome to. let me know.
Dave

Hi Jens - that Bandit is way too nice to become a hangar queen.. Hope you get it tweaked out soon. Dave's offer sounds like a good start

kasra, the damage is not so bad. the wings were just mounted with wooden dowels and epoxy, this whole thing broke off the fuse during "lawn darting". i show you next time on the field.

dave, thanks - your offer sounds really tempting! i "just" have to get a smaller BL controller. i will contact you off board about the motor.

haldor, hangar queen?! no way, i won't give up until this jet flies zippy. with dave's help it will hopefully get the needed power.

one thought was, to make a new, lighter version of the mini bandit which has unsheeted foam wings, just stiffened by strapping tape and the covering. this should save at least an ounce. any other advices on how to save weight?

I can send you a jeti BL 18 amp controller, about as light as they come. I assume you aready are using micro size servos, (hs 50's or 55's) and a light Rx (case removed). What is the AUW of the wing with servo? for ref. the Minx is about 1.5 oz. it is made from 1/32 balsa D tube contruction, and has a single hs 50. Also what size balsa did you use for the fuse? Contest grade? I also like dope and tissue to keep weight down, but econokote is pretty good too, but I am behind in what is out there that is really light and does not require dope. Outside of that there is only so much you can cut, The only other thing would be to lighten up the motor/batt/controller. I will weigh the hacker/jeti/7 cell 600ae pack against the astro010/jeti/10cell nimh 720 pack and report back the weights. I did not do an RPM test with the hacker on a 7 cell pack, the astro 010 on 10 720's was 31k. If the hacker is about the same and you can only use the 7 cell pack, then the astro may be the way to go if it is lighter.

i am using 2x HS-50s for the tailerons. the receiver is a micro receiver, the battery leads are as thin as i thought i could use for this amperage (18ga). for the fuse i used regular 3/32" light balsa wood. just one former is made out of light plywood.

the foam wing cores were 10gram (0.35oz) each half when they were unsheeted. sheeted with contest balsa using 3M Super77 adhesive they came out 21gram (0.74oz) each! when you have to add the ultracote covering you end up with almost an ounce for one side. that's why i thought about leaving them unsheeted.

for the ducts: is this clear mylar stuff lighter than the light cardboard i used?

the 010 setup might be lighter than the hacker setup, but the performance will also drop, when you compare 31k RPM 010 vs. 36k RPM B20. i could stuff 8 or 9 600AEs in the fuse if necessary.

What about a build-up wing ?

What about a build-up wing ?

i was thinking about this, too. but i received new foam cores made from lighter white foam, instead of the heavy blue foam. the new cores are half the weight now, this alone will save .5 ounce.