Author Topic: YIPPEE P-38 Lightning RTF... (Read 3360 times)

wwwarbird · « **on:** June 04, 2019, 07:53:05 PM »

Well, I've finally finished the Don Hutchinson P-38, YIPPEE!!!

Power is two bone stock OS.35FP's turning Tornado 10x6 3-blade props with Tru-Turn FAI spinners and Perfect 4oz wedge tanks. Finish is all Brodak except for the "Vermillion Red" overall color that came from Randolph. Final clear is Brodak "Crystal Clear". Wing is covered with Polyspan and the rest of the model was covered entirely with medium silkspan. Controls are one-off aluminum bellcranks built per the Hutchinson plans combined with Tom Morris leadout wire, C/F pushrods with titanium ends and ball links throughout. I haven't gotten it on the scale yet but will update with that info soon...

wwwarbird · « **Reply #1 on:** June 04, 2019, 07:58:44 PM »

More pics...

wwwarbird · « **Reply #2 on:** June 04, 2019, 07:59:51 PM »

Top-n-bottom...

Crist Rigotti · « **Reply #3 on:** June 04, 2019, 08:25:04 PM »

Ya done good Wayne!

pat king · « **Reply #4 on:** June 04, 2019, 09:06:09 PM »

Looking good, Wayne

Pat

wwwarbird · « **Reply #5 on:** June 04, 2019, 09:11:07 PM »

Thanks guys,

Just two test flights so far, this past Saturday evening at the Polk City, IA Stunt/Carrier contest. Initial flights on 64' lines went really well with it tracking like it was on a rail. I was actually surprised that it wasn't a lot faster since I'm running .35's in place of the recommended .25's. I was sort of expecting to have a red rocket to work on slowing down a bit. I didn't get any lap times but launching it at 9300 rpm the speed was really comfortable. The rest of the world thought I was nuts for hanging the .35's on it but it felt really good cooking along out there with great power everywhere.

Flying upright the outboard tip was up just a bit, forgot to look at it inverted, dang. I'll have to check next time out but I think a simple flap adjustment should even things out there. I need to dial in some more elevator as it was fairly slow on the controls but it feels like it's all there just waiting to wake up. Overall everything shows great promise and after some minor tweaking I'm confident everything will fall into place, it doesn't need much.

Gary Dowler · « **Reply #6 on:** June 04, 2019, 09:20:23 PM »

Quote from: wwwarbird on June 04, 2019, 09:11:07 PM

Just two test flights so far, this past Saturday evening at the Polk City, IA Stunt/Carrier contest. Initial flights on 64" lines went really well with it tracking like it was on a rail. I was actually surprised that it wasn't a lot faster since I'm running .35's in place of the recommended .25's. I was sort of expecting to have a red rocket to work on slowing down a bit. I didn't get any lap times but launching it at 9300 rpm the speed was really comfortable. The rest of the world thought I was nuts for hanging the .35's on it but it felt really good cooking along out there with great power everywhere.

Flying upright the outboard tip was up just a bit, forgot to look at it inverted, dang. I'll have to check next time out but I think a simple flap adjustment should even things out there. I need to dial in some more elevator as it was fairly slow on the controls but it feels like it's all there just waiting to wake up. Overall everything shows great promise and after some minor tweaking I'm confident everything will fall into place, it doesn't need much.

Slow pitch response , coupled with "tracking like it was on rails", sounds like a classic nose heavy condition. More elevator won't counter this. Place an ounce on the tail and try it again. I'll wager you will see significant improvement.

Gary

bill bischoff · « **Reply #7 on:** June 04, 2019, 09:31:07 PM »

Aren't the lines a little short?

wwwarbird · « **Reply #8 on:** June 04, 2019, 09:31:56 PM »

Quote from: Gary Dowler on June 04, 2019, 09:20:23 PM

Slow pitch response , coupled with "tracking like it was on rails", sounds like a classic nose heavy condition. More elevator won't counter this. Place an ounce on the tail and try it again. I'll wager you will see significant improvement.

Gary

Very possible Gary and something I do plan to be looking at. One note though is that it didn't have the slightest tendency to drop the nose once the engines quit, or pitch up, it just continued forward with a nice level and very controllable glide. FWIW the flap/elevator setting is currently 1:1 so I do feel like I can feed it more elevator, we'll see.

wwwarbird · « **Reply #9 on:** June 04, 2019, 09:34:17 PM »

Quote from: bill bischoff on June 04, 2019, 09:31:07 PM

Aren't the lines a little short?

Maybe, but that's what I had on hand for the moment.

Clint Ormosen · « **Reply #10 on:** June 04, 2019, 10:05:07 PM »

Came out pretty darn good, Wayne. I'd love to fly it!

wwwarbird · « **Reply #11 on:** June 04, 2019, 10:20:13 PM »

Can't resist this comparison...

Dennis Leonhardi · « **Reply #12 on:** June 05, 2019, 09:13:38 AM »

Awesome Wayne! Can't wait to see it fly …

Dennis

Air Ministry . · « **Reply #13 on:** June 05, 2019, 09:39:52 AM »

Yep, @#$% hot .

Dunno if the Tornado 10 x 4s , if youve got some , mightnt pan out . Sort of lower gear , locked in , with a few more revs .
The old OS 35S like them . Pulled my ten ton P-38 , on one , through a loop or two .

Larry Renger · « **Reply #14 on:** June 05, 2019, 09:47:24 AM »

You specified 64 INCH lines. Wow!

Jared Hays · « **Reply #15 on:** June 05, 2019, 09:10:25 PM »

Flight video from Des Moines Contest with Keith Sandberg at the controls.

wwwarbird · « **Reply #16 on:** June 05, 2019, 09:38:32 PM »

Quote from: Larry Renger on June 05, 2019, 09:47:24 AM

You specified 64 INCH lines. Wow!

DOH! Good catch Larry, I suppose that's what Bill was getting at too, I meant 64 FOOT lines, thanks!

wwwarbird · « **Reply #17 on:** June 05, 2019, 09:51:51 PM »

Quote from: Jared Hays on June 05, 2019, 09:10:25 PM

Flight video from Des Moines Contest with Keith Sandberg at the controls.

Thanks Jared! That was the second flight with Keith pulling just a few soft maneuvers.

Air Ministry . · « **Reply #18 on:** June 05, 2019, 10:57:23 PM »

Not a lot to complain about there .

Gary Dowler · « **Reply #19 on:** June 05, 2019, 11:17:11 PM »

It looked smooth and predictable. But it did look sluggish on pitch. Was this due to the pilot? This will often be the result of being nose heavy. It can also come from too small an elevator on a flapped plane.

Gary

Jerry Eichten · « **Reply #20 on:** June 06, 2019, 01:14:05 AM »

Really nice Wayne. Good job!

Peter in Fairfax, VA · « **Reply #21 on:** June 06, 2019, 08:18:04 AM »

Nice job. Always enjoy the sound of a twin. Any multi, really. And it has a stylized look to it, as well, with the bright color and markings.

Question: Have you given any thought to uniflow tanks? Wasn't able to observe the end of the flight on the video, but my experience is that this arrangement has less of a tendency to lean out near the end of the flight.

Peter

Jim Carter · « **Reply #22 on:** June 06, 2019, 08:37:51 AM »

Hi! That really looks nice. I've done a bit of browsing to see how to acquire one of these kits or even the plans but I've had no luck figuring out where or who to contact. There is a really neat build log for the Hutchinson kits over on the Stunt Works site but again I couldn't find any contact info. Can anyone help?

Don Hutchinson AMA5402 · « **Reply #23 on:** June 06, 2019, 04:48:38 PM »

Hello Jim-
Send me an e-mail and I can supply plans. There are 25 warbirds in the series, plans unlike any you usually see!
Don

dhutch2@yahoo.com

Clint Ormosen · « **Reply #24 on:** June 06, 2019, 09:47:45 PM »

Twins sound so cool!!

Outstanding effort, Wayne!

wwwarbird · « **Reply #25 on:** June 06, 2019, 10:49:28 PM »

Got it on the scale tonight, 84.5 ounces. Of note here is the fact that my scale reads actual weight, unlike some others on this forum.

It's a little heavier than I'd hoped but it didn't seem to be a big problem on the initial flights. Kind of weird, my PBY came out at 84 ounces RTF too, the P-38 doesn't pull as hard as that one though. Whatever the case, it is what it is at this point.

wwwarbird · « **Reply #26 on:** June 06, 2019, 10:53:04 PM »

Quote from: Gary Dowler on June 05, 2019, 11:17:11 PM

It looked smooth and predictable. But it did look sluggish on pitch. Was this due to the pilot? This will often be the result of being nose heavy. It can also come from too small an elevator on a flapped plane.

Gary

Gary,

The "smooth and predictable" was the pilot, the "sluggish on pitch" was the airplane, and that will get dealt with. Keep in mind this was only the second flight on an all new model, just getting a feel with a few big soft maneuvers, we weren't going for the Combat corners or contest day bottoms at this point. So far I'm considering it a success.

wwwarbird · « **Reply #27 on:** June 06, 2019, 11:01:29 PM »

Quote from: Peter in Fairfax, VA on June 06, 2019, 08:18:04 AM

Question: Have you given any thought to uniflow tanks? Wasn't able to observe the end of the flight on the video, but my experience is that this arrangement has less of a tendency to lean out near the end of the flight.

Peter

Right now it's the Perfect standard wedge tanks on muffler pressure, a simple setup I've typically had good luck with. It seemed to work perfectly here too, and I'm a big "if it ain't broke don't fix it" guy, K.I.S.S.

jim gevay · « **Reply #28 on:** June 07, 2019, 05:19:18 AM »

As great as it looks on the ground, it should look even greater in the air. Hope to see it soon Wayne, well done.

Jim Carter · « **Reply #29 on:** June 07, 2019, 03:17:20 PM »

Quote from: Don Hutchinson AMA5402 on June 06, 2019, 04:48:38 PM

Hello Jim-
Send me an e-mail and I can supply plans. There are 25 warbirds in the series, plans unlike any you usually see!
Don

dhutch2@yahoo.com

Done! Thanks again!!

Norm Faith Jr. · « **Reply #30 on:** June 07, 2019, 11:15:22 PM »

That is one nice looking plane! I've got a set of the prints...been waiting to see one done and in the air...I'm now going to have to build one.
Norm

wwwarbird · « **Reply #31 on:** June 17, 2019, 09:12:30 PM »

A great pic of the maiden flight launch...

Clint Ormosen · « **Reply #32 on:** June 17, 2019, 11:03:28 PM »

Are you flying, launching, or taking the picture?

Michael Schmitt · « **Reply #33 on:** June 18, 2019, 07:15:18 AM »

Looks great Wayne!!!

wwwarbird · « **Reply #34 on:** June 18, 2019, 07:02:07 PM »

Quote from: Clint Ormosen on June 17, 2019, 11:03:28 PM

Are you flying, launching, or taking the picture?

I'm the fat guy out there holding the handle.

Serge_Krauss · « **Reply #35 on:** June 18, 2019, 07:27:08 PM »

Really nice job! Thanks for the pictures and update.

jim gevay · « **Reply #36 on:** June 19, 2019, 06:31:02 PM »

That's a great photo of you and Keith, thank the photographer.

wwwarbird · « **Reply #37 on:** June 19, 2019, 06:49:13 PM »

Quote from: jim gevay on June 19, 2019, 06:31:02 PM

That's a great photo of you and Keith, thank the photographer.

I agree, an excellent impromptu photo! I couldn't resist either, I just picked up an 8x10 print of it tonight to go on my shop wall. Having a few of these photos sprinkled around the shop helps for inspiration if I get bogged down during a build. I'm not sure, but I think Tom Sontag gets the credit for this one, thanks Tom!