Welcome, Guest. Please login or register. October 25, 2016, 01:16:56 PM

Login with username, password and session length

Pages: 1 2 3 [4] 5 6 ... 10
 on: Today at 07:56:52 AM 
Started by Geoff Goodworth - Last post by Motorman
I would put a little bit just to make sure it's not going the wrong way. Helps the plane groove.


 on: Today at 07:39:12 AM 
Started by Norm Faith Jr. - Last post by Joseph Patterson
  Yes Dan, that's right!

 on: Today at 07:34:52 AM 
Started by Matt Piatkowski - Last post by Matt Piatkowski
Hi Dave,
I know that my approach looks weird but the engine is weird too.
This particular Jett60 is a hybrid of old and new parts and does not run like "normal" Jett. Specifically, it could not reach the ground RPM that are expected from Jett60 on certain props., no matter what I did with variables like fuel, venturis, NVA, glow plugs etc. This deficiency manifested itself very clearly when the engine used Jett's header/muffler only and there was no pipe.

Without going into too many technical details that are described in my previous posts, I can tell you that this engine has some form of fuel transfer timing problem.
You probably know that timing is a very sensitive mechanism and minute differences in ports geometry and surface roughness in critical areas have large impact on the overall engine performance, power, RPM and torque.

Yesterday's tests showed, for the first time, that this engine run better with pipe. Perhaps I was simply lucky when I set the pipe working length (18" and 1/8"), but the ground RPM a little bit below full 2 cycling were much higher than when using only header/muffler with other variables unchanged.
This means that the pipe is "helping" the engine to improve the timing problem, whatever the true nature of this problem is.

The RPM increase on 3blade carbon composite 11' and 7/8'x4" Bolly prop. is especially encouraging and, in my opinion, allows to start thinking about the stunt plane, lets call it the Advanced Stunt Trainer (AST) that will be build around this engine using this (or equivalent) prop and the pipe.

The entire power plant (Jett60 with header, propeller, propeller nut, pipe, pipe silicone connector and the connector clamp) weights about 500 grams (17.6 oz.).
660 in.square wing, lightly build with bellcrank, bellcrank mount, bellcrank to pushrod wire connection, leadouts and light heat shrinkable covering - 375 grams.
Partially build up (front portion only) fuselage with partially hollowed maple engine mounts, Sullivan fuel tank, carbon composite landing gear, light wheels and covered with light covering - 450 grams. Tail surfaces - 80 grams (very conservative). RTF model estimated weight -1405 grams (49.56 oz.). Even if I underestimated the RTF weight by 3 oz., the plane should fly ok for the training purposes with the wings loading around 11 oz./sq.ft.

I have learned to successfully mix different structural materials (foam, balsa, carbon composite stiffeners, Depron, various coverings etc.) and can build very lightly, maintaining reasonable stiffness and strength of critical elements.


 on: Today at 07:33:25 AM 
Started by Avaiojet - Last post by Avaiojet
Hi Charles,
Really coming along!

Hey! Hey! Craig, from down under!
Gorts helmet needs to be colour coordinated with the aircraft.

Ya think! I'm kidding with that "Ya think."  Orrrrrrrrrrr, a color that goes with everything? Is there a color that goes with everything?

Love how he looks! Keep it up mate.

Gort's coming along.

What are the advantages of an adjustable rudder?

There's more advantages to flight performance with a rudder that's adjustable than one that is fixed.   Layingdown

I think the concept of adjustable rudders made the cover of VOGUE once, much has been written about them. I may have gotten in trouble once, maybe twice, asking about that or set-ups? It gets blurry with my replies of yesterday.

I watched Windy do a functioning rudder and worked out why.

Windy who? Oh, that Windy.  Layingdown Layingdown Layingdown

The panel cover really works! Finishes it nicely.

Thank you. That's how it was probably done. Maybe I should wrap it with leather and lace it?

I might try to get the rudder silked today.

Have a great week.

You too and thanks for the reply.


 on: Today at 07:09:09 AM 
Started by fred cesquim - Last post by fred cesquim
hello Charles!
what about the Horn axle? do you recess it as well?
curious to see how it works

have started finishing here

 on: Today at 06:55:15 AM 
Started by Steven Kientz - Last post by Don Jenkins
Finally done with the checkerboard!  The paint mask worked well, and I used individual squares from it to mask the flaps and elevators so everything aligned pretty good.  I'll mask and paint the fuselage next and finish this thing up so I can focus on my next PAMPA plane!


 on: Today at 06:19:49 AM 
Started by Bootlegger - Last post by CL-flyer
Looks like both of these are the same.


Original Tomahawk Kit   
by Brodak:

 on: Today at 06:02:30 AM 
Started by B Norton - Last post by De Hill
I called Lew Woolard at the hospital last night (Monday, Oct. 24) and he sounded good and said that he should get out of the hospital today.

It was a relief to hear him sounding like he normally does.

 on: Today at 05:58:04 AM 
Started by B Norton - Last post by De Hill
Elwyn and I left Tulsa at 6:45 am and headed for Wichita; it took 3 hours to get there. We arrived at Planeview Park in Wichita, and met  Steve Albers, Doug Burright, Gary Mondry, and Pat McElraby. We put on a stunt clinic and Gary Mondry flew several flights to train the new judges.

Sunday morning, Bob Brookins showed up at the contest, and we watched the new judges score the contestants in Beginner, Advanced, Expert, Old time Stunt, Classic, and profile stunt. After it was over, Bob Brookins handed out the stunt awards.

 on: Today at 05:36:14 AM 
Started by Matt Piatkowski - Last post by Dave_Trible
Matt I don't think anyone considers picking an airplane to mate a prop.  You really need to do it the other way around.  You DO mate an airplane to a chosen power plant.  For the Jett .61 on a pipe 630 is acceptable but minimal.  You'd better build it very light.  Your 53 ounces?  Good luck with that.  The hardware alone including engine, coupler, pipe, tank, wheels, prop, spinner, and fasteners will be about 25 ounces.  Most covering and finishes will average 10 ounces.  That leaves something like a Ringmaster for an airframe to maintain your 53.  Odds are you might build a little heavier than a master so your wing loading will run pretty high for 630.  I'd suggest a known design over 660 sq. inches and find the right prop for your finished product.


Pages: 1 2 3 [4] 5 6 ... 10

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines

Valid XHTML 1.0! Valid CSS! Dilber MC Theme by HarzeM