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eflight-ray
05-12-2006, 06:23 PM
Managed to get my old B25 Mitchell airborne again, after a 3 year rest, (the plane, not me).
It will be 13 years this June since it first flew, and has normally had a few outings each year, but what with moving house 2 years ago and getting the ‘I must build something new’ bug over and over again, it sat collecting dust.

Well it got a dusting down, a good checking over, and a rethink.

It was a originally powered by two Speed 600 12v motors on 14 cell each, with everything in series, that meant 28 cells. Now that was when 1700mAh nicads were big capacity.

So a rethink with the GP3300 nimh cells I now use meant that it could go to parallel motors on just 14 cells, (a saving of about 2lbs weight).

I had also used Punctillio 12x8 wood props, mainly because I could get normal and reversed pitch for ‘counter-rotating’ props, (no torque effect).

This time I felt that a change of prop to an electric type might be worth while, so on went a pair of APCe 14x10’s. Don’t ask why 14x10, I had ordered them some time ago for something that I never got round to, so why not.
Well they work, but draw 34 Amps at the start, but she sure does climb out better now. And will cruise on very low throttle, and the torque effect is minimal.

Well here’s a few pics of her in action, please ignore the look of worry, (pain?), on my face, I really was enjoying it. You should have seen the ‘grin’ after touch down. :D
(special thanks to Mike Greenslade for the pics)

firemanbill
05-12-2006, 06:26 PM
Sweet looking bird ya got there Ray! nice work

crxmanpat
05-12-2006, 06:51 PM
Ray,

Very nice! Isn't it fun when you get to maiden a plane all over again after upgrades?

Wow, looks like you could trim the grass with those props while taxiing!

Do the bomb bay doors work? Looks like they might. Ever dropped anything from it? Now that you have saved 2lbs in battery weight, some powder bombs may be in order!

Cheers!

bsoder
05-12-2006, 06:54 PM
Beautiful plane, Ray. Any chance of some more pictures? Or flight video? :)

eflight-ray
05-12-2006, 07:31 PM
Pat

It can drop bombs, I can carry two fairly large ones, (rather over scale), the're made from a rolled balsa sheet body, foam nose, with a paper cone and fins. The idea being that if the're big and light they can be seen for longer.


I do have some 8mm cine of its first flight, (22nd June 1993), I must try and get it converted.

crxmanpat
05-12-2006, 07:42 PM
Ray,

I know it don't look pretty, but you can add some flourescent streamers to the rear of the bombs also for added visibility. The drop module for the Hobbyzone planes includes two plastic bombs with streamers, and a paratrooper. The bombs can be seen from 500' up.

vax6335
05-12-2006, 08:49 PM
Maybe get some 3 blade props for better clearance and looks?

Bill G
05-12-2006, 09:04 PM
Maybe get some 3 blade props for better clearance and looks?

That's what I thought. It looks like its doing a little lawnmowing in the first pic. Nice plane though.

eflight-ray
05-13-2006, 11:50 AM
Just had a fright. Giving it a thorough check over, looked at the props again.

There not 14x10's, there........

....14x12's, Please, no one say it out loud, just in case the planes listening.

Why, I just don't know, but like I said they work, (perhaps rather hard).

Bill G
05-15-2006, 04:32 AM
Please, no one say it out loud, just in case the planes listening.


They do listen. Why do you think a bad flying plane just keeps getting worse?

Finally got the B25 back up:eek:
On that note, boy I wish I could get my Control Panel back up.

_____________
Why do people keep going back to places they can't stand?

if last edited, it was for no good reason

eflight-ray
06-27-2011, 01:59 PM
Only 5 years to wait, but I managed a video at last, this morning actually.

She never left the hangar this year till now, lots of dust, cobwebs, and good old faithful Nimh cells. They held a fair voltage, and charged well, but I really should cycle them to bring them back up to speed.

She had her official flying birthday only a few days ago. First flew 22nd June '93.

http://www.youtube.com/watch?v=tg0eLNHrEEw
(http://www.rcgroups.com/forums/showthread.php?t=1343353&page=56#post18608695)

crxmanpat
06-27-2011, 10:41 PM
Ray,

Wow, a blast from the past, about a blast from the past! :p>

Great flying. Hard to believe you're still using brushed motors and NiMH packs. And it flies scale, not like a barn burner.

Well done.

acdii
06-30-2011, 07:07 PM
Imagine lighter brushless, ESC and Lipo's, you could drop real bombs with it. J/K, wouldnt want to be anywhere around if you did! :)

So you flew that as an electric way back in 93? I didn't know they had anything strong enough to use in a plane way back then, but then again I was not really into it during the 90's, I had given it up in the late 80's until just recently.

TM4197
07-01-2011, 03:25 PM
That is a very nice plane..Great job flying. and I want your flying field!
next vid.....drop some flour bombs![popcorn]

road king 97
07-01-2011, 06:06 PM
Very very nice ray she looks great and looks to fly very well also. :D joe

Fishbonez
07-01-2011, 06:24 PM
Wow what a video. I think that may be one of my all time favorites. That plane looks Sweeeet in thw air. Very graceful for a lady her age. The greenery was beutiful as well what a great place to fly from

CHELLIE
07-02-2011, 12:37 AM
Very nice plane Ray, it flies very well, Glad you had a good time flying a blast from the past again :) Take care and have fun, Chellie

eflight-ray
07-02-2011, 08:45 PM
As she has 'come of age', 18 years old, I have bought her some jewelry.

Two brushless motors to be precise, and a couple of Lipos to feed them.

Now I just hope she doesn't mind me fiddling inside her cowls to make a few adjustments ;).


The annoying thing is, I'm now getting a collection of relatively useless belt drives, (couldn't stand whining gearboxes, and belts made a nice realistic 'rumble'). That's two from the B-25 and four from my B-17. Plus of course a few brushed motors as well.
Kids!, the things we do for them. :roll: