Dec 06, 2009, 05:11 PM
Registered User
JCL's Avatar

'Nother Drenalyn

I built a 21" span drenalyn out of PBIII.

AUW ~9Oz with 3s 800mah battery

BW brushless, 9g HXT servos, HXT esc and AR6000 RX.

Maidened it today in slight winds with gusts.

I made the rudder too small (didn't scale it up enough from the 17" plans), but that didn't see to harm anything.

Flew well, no drama. It does really like to climb with throttle, but flew great except for that. I think I have too much right thrust as it goes that way under power even if trimmed for straight glide.

Rolled okay, I could up my aileron throws, but it is fine for now. Elevator throw is probably a bit much, but not a real problem. Rudder definitly helped on turns.

I wasn't able to really hover, but I could fly very high alpha into the wind.

Only one minor crash due to dumb thumbs. I was in a near hover low but I was a little close to the flight line. I didn't manage a good transition from high alpha to normal forward flight. No real damage.

As is my habit, I forgot to take pictures before first flight.
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Dec 10, 2009, 08:11 AM
Registered User
davereap's Avatar
just made a new video
drenalyn2.AVI (7 min 9 sec)

Its been a good day for flying, the sun is out and the wind is strong, but not a gale as it has been lately.
The Drenalyn had a new motor mount fitted so I can adjust the thrust lines easier.. The video is only its second flight,
Thrust lines still need more down and I think its flying nose heavy because its inverted is not so good.
A few teething troubles at the start but I enjoyed the flight and think this one is another keeper... cheers to the designer..yet again.
The wheels are now better fixed... I am glad I used a removable UC system because it only took a couple of seconds to get back flying, not a return to home job..
The COG needs to go back a bit, but I will have to move a servo to get this correct.. so a job for tommorow.
The video was made using one of the gumpack cameras fitted to a headband.. not bad for a £5.55 camera.. the card for the camera was twice as much..and its only my second go with the cam.
Last edited by davereap; Dec 10, 2009 at 01:36 PM.
Dec 10, 2009, 12:25 PM
flyin' fool
goldguy's Avatar
It's way too cold to go flying here today, so got my flying fix from watching your video. Thanks for letting me have a turn on your sticks.
Dec 28, 2009, 03:06 PM
Registered User
JCL's Avatar

A couple of pics

Nothing special, just some blue foam.

The first picture shows why I want to give this a 25 cent paint job. Does this shape remind anyone of anything?

And also gives me an idea on how to paint my next nutball. Waka Waka Waka!

Dec 28, 2009, 06:25 PM
For us He died, in me He lives
Jimmy JFlyer's Avatar
Now if you can just remember all the Ghost's names.
Dec 29, 2009, 01:17 AM
flyin' fool
goldguy's Avatar
No, but I am reminded that the blu foam bends one way better than the other. I've got a 15 incher with the bends against the ripples and had to get mad at it to get it to hold it's shape.

Other than that, it looks good and you'll have a blast with it. Got mine all polished up and ready for our New Years Day bash.
Last edited by goldguy; Dec 29, 2009 at 12:21 PM.
Dec 29, 2009, 09:58 AM
Curiouser and curiouser
Kokopeli's Avatar
Okay, so as to just get my "ripples" thinking straight.
Are JCL's ripples going in the unrecommended direction? (see pictures on post #259)

Dec 29, 2009, 12:26 PM
flyin' fool
goldguy's Avatar
It bends easier when bent parallel to the ripples and yes, it's only a recommendation.

I bent the foam for my new blu one like Joe's and had to force the bend at the rounded tips with heat and brute power for it to stay permanent.
Dec 31, 2009, 01:57 PM
For us He died, in me He lives
Jimmy JFlyer's Avatar
Nice to see this guy in all blue. Still have half a bundle downstairs...
Hmmm, which plane gets to donate it's guts.
Jan 30, 2010, 06:50 AM
flyin' fool
goldguy's Avatar
My poor old 19 incher took a real thrashing over the summer, mostly from impromptu combat and letting others take a turn. It was either the scrap pile or a major rebuild. Since it's one of my better flying Drenalyns, I chose the latter. Here's the results with a cover up paint job...................
Jan 30, 2010, 10:21 AM
Registered User

Another build

Just to let you know, Goldguy, that the Drenalyn is a popular build. My friend in North Carolina built one (about 20” or so) and we all oohed and aaahed appropriately about the fantastic way it handled. He has since built a 13” or 14” and helped his brother build a larger outside one. I found your thread and have built a 13” and a 20” one from the plans posted by Atx_Heli. Thanks for the great plans and the spreadsheet.
My 13” one is 3m Depron, powered by a 1811-2000 with a 360mah Rhino battery, HXT500, 5oz servos and no rudder. It is 3.5 oz with bat. I haven’t tried it yet as with my flying skills, a large garage is nowhere big enough and weather has been much to cold and blustery here in the mountains of Virginia. My 20” one is blue foam with Blue Wonder, TG9oz servos and finishes out at 8.3 oz with a 1000mah Zippy. It flies very nicely even though I got the wavy lines wrong. Very floaty and runs like a bat out of hell when I jam the stick. I got one try a couple days ago in my front yard and the house and trees were in danger. I missed them in spite of my dumb thumbs. I used the extended motor mount for balance but they look like they will be very susceptible to breaking. Worked great to balance the small one but the big one still needs battery all the way forward. I’ll post a few pictures of each. The little one first and then the big one. Thanks for your great plans. Much fun on snowy days. We have 9” today from last night and it is still coming down. PROJECT DAY!!:
Jan 30, 2010, 11:11 AM
flyin' fool
goldguy's Avatar
Wow, it's nice to hear others are pumped up with 'drenalyn'. Yup, it's one of the best LAR fliers out there. I still don't get it that others don't get it. The Drenalyn solves two problems that haunt flatties, pitch problems and smooth inverted flight. It doesn't care if it's right side up or up side down and at any speed. What more could you ask for?

I've got a 17 incher that ended up with the wrinkles the wrong way too. I just kneaded it with the flats of my hands where it bends down towards the LE and at the tips where it bends up produce the reflex and it worked.

When you get some nice weather, haul that big one up into the mountain for some sloping. I've done it with mine and you'd think it was a glider.

Snow. We get rain in the winter, just as bad for flying and it looks like for the next 10 days or so. And just think, we have the winter Olympics just around the corner from here in just a few days. Could be .
Feb 28, 2010, 08:14 PM
still learning
aeroknot's Avatar
any size recommendations for
2mm depron / 10g motor / front yard (13 inches?)
3mm depron / 24 g 1500kv motor / outside (20 inches?)
Mar 02, 2010, 08:49 AM
still learning
aeroknot's Avatar
For the 24g motor, I'll try:

airfoil 3mm depron, 25 inch wingspan

fuselage, 3mm depron probably laminated with 3mm epp (2mm would be better), front box tapered back fuselage

motor mount thin ply with epp with landing gear like the later dart landing gear
Mar 02, 2010, 02:18 PM
still learning
aeroknot's Avatar
here's a misc approximately 5-24 airfoil, scale to suit

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