orthobird

My Feedback: (1)

bottom of the wings are sheeted. still have a long way to go before i can sheet the top of the wings. the da 85 will definitely fit on this bird, it is only the muffler, i am in need of one. I also had to build my own motor mount. it weighs 3 ounces.
i have also weighed all the parts, minus the muffler, covering/paint/fuel tank/and servos, it weighs 18 pounds. not bad!!

rossmick

Mpizpilot

Thanks for the comment on the cockpit. Yes, the struts are turned around for testing as I did not want to cut the axle bolt off until I had satisfactory, consistent, retraction. Unfortunately, that never happened with the CJM gear. Now I have an expensive set of bookends, or maybe I will put them in a boxed picture frame labeled 'Not my greatest idea' and hang it in the shop as a reminder. I am waiting for the Sierra gear, and once received, will run the airlines, install the value and setup the servo to operate the value. I understand that the tail attach points will have to be re-engineered to install the Sierra tail wheel, so there will some work to be done before this bird gets in the air. I am not sure about the air line disconnect arrangement, but will see how others have managed it. Too bad it could not all be held in the wing, but the line to the tail wheel would still need some disconnection so might as well keep in all in the fuselage.

Mpizpilot

My Feedback: (45)

I went through something very similar to what your are going through with your gear. I had a ESM BF-110 that I went round and round with the gear on. Started with the stock ESM air units which were garbage, spent $250 to convert them to electric lado's which didn't hold up either. Finally just sprung for the Sierra units. All said and done I spent over $1000 on the gear. I feel your pain.

Mpizpilot

My Feedback: (45)

Here's a couple of pics of mine that I'm working on. I kinda made up my own scheme, not too worried since I'm not scale competitor.

sjhanc

My Feedback: (3)

orthobird,
If you cant the cylinder head 20 degrees away from the exhaust port you will not have to butcher the cowling side for a muffler hole. You will have to install a reinforcement mount strap between the muffler and the engine mount to prevent the bolts from constantly loosening in flight. With out this strap the bolts won't make one flight with out loosening and can do serious damage to the cylinder mounting flange requiring machining or replacement. Use of thread locker will not prevent loosening of muffler bolts and may cause the threads to pull out of the cylinder head. This is a problem with all gas engine sizes but is greatly exaggerated with larger engines. I have used a ZDZ 80 in several of my P 51 airplanes and had to buy a new cylinder on one occasion and machine the cylinder flange another time. This is not an out of balance condition but is caused by the extreme power pulse the bigger engines deliver to the airframe. You can see it in the wing tips as a blur at lower throttle settings and control surface buzz.

sjhanc

My Feedback: (3)

Incidentally both my kit and ARF built planes grossed out at 29lbs without needing ballast weight, but they both flew fine at that weight. Take off and landing speeds were slower with the 26 inch props this size engine uses. I think the big prop (26 1/4 inch is scale diameter for the Mustang) blows more air and covers most of the flap span giving more lift. Just don't chop the throttle to idle and expect it to glide the large prop has much better braking action, the plane will suddenly stop and drop. I keep high idle speed on and don't reduce power until the wheels are rolling. Another characteristic with large props is that when you turn it into the wind for take off, a too sudden increase in throttle with the tail wheel on the ground will result in the plane jumping into the air and it is not flying. It will torque off to the left, drop the left wing tip and cartwheel. 20+ lbs of balsa in a cartwheel never ends well. As far as general ground handling compared to smaller props I think it is much better with little torque steer and much shorter take off runs at a little above idle power. I advance throttle slowly until the tail is up then continue to increase power a click at a time. It will be off and climbing by the time you get it to 1/4-1/3 throttle and you can use 1/2 for verticals. Don't chop power on the downside, the braking action of big props will stop the plane and cause instant stalls at low altitudes that can't be recovered. I increased flap travel and fly approaches at 40-50% power until touch down. They don't glide with big props idling.

orthobird

My Feedback: (1)

thank you very much for the great advice.

what size spinners are you all using?

sjhanc

My Feedback: (3)

On my first 2 planes I used the supplied 5" spinner, however the first one came off in flight and disappeared into the swamps at the Sanford Fl. club field. The second developed a crack radiating from one of the prop cutouts and I replaced it with a 5" Tru-turn. That spinner lasted for 317 flights until the fuselage broke in half during a radar speed check at 122mph. The guys in the Dunnellon who witnessed the crash said that the crater in the runway was the largest they had ever seen. The beautiful Tru-turn was molded back around the crankcase. That engine is still in the junk box. My brother wanted me to make a wall plaque with the spinner. I didn't want to be reminded of it so it was sold with scrap aluminum.
Now I used Dave Brown Vortec 5" spinners and if I have money to burn an occasional Tru-Turn. I now reinforce the fuse with 3/4" triangle stock at the bulkheads and haven't any more fuse failures. This is the plane that took the famous dive. It was a sweet flyer while it lasted.

JDjetjock

My Feedback: (2)

I'm using a Tru-turn 5.5" spinner with the Leo Spychalla cowl. Looks much more scale.

Cheers,

orthobird

My Feedback: (1)

SSJHANC, thank you very much for the great advice. i appreciate you. this is really good to know. i have been practicing this on my simulators. and you are definitely correct, even on the sims, the warbirds want to stall, so i come in to land with power, and once about 1 or 2 feet above the runway, i start to cut power down, and it lands nicely. again, this is on a sim, heaven knows how i will do the 1st time.

sjhanc

My Feedback: (3)

Just remember, when you cut power, it stops flying. If the wheels are more than 6 inches off the ground it will drop and bounce and this airframe is famous for wing and landing gear damage from bad landings. Most pilots are used to lighter sport planes that will glide to the runway when power is cut- this plane needs air blown against the flaps for gentile touch downs. And if you cut power below a fast idle on the rollout the big prop creates a drag bucket behind it that blanks airflow over the tail surfaces. This is the cause of nose overs and ground loops that are embarrassing at the least or broken props and damaged landing gear. You can read about these problems in this thread and others. When the plane touches down strong airflow over the tail maintains good control. The weight of a 20lbs.+ airframe bearing down on the wheels is going to slow it as long as power is below take off power. It is a plane that needs a long enough runway to land and run out. Every now and then I find I have arrived at touch down at just the right angle of attack, airspeed, and throttle and it will do a beautiful 3 point landing. This combination of ideal factors happens so rarely that I have stopped trying to do it as a regular event because if it isn't exactly right, it turns into a disaster. Much better to power it on under full control. The day the picture above was taken this was the only landing that worked like I wanted. I did 5 flights and 10-15 touch and goes on each flight. When I got this landing I packed it up and went home.

orthobird

My Feedback: (1)

what a beauty that one was. sorry for your loss. it is not only the airframe, but the time and dedication. I feel that pain as well. been there.

sjhanc

My Feedback: (3)

Thanks, It takes a lot of nerve to commit that much work and money to this particular part of the RC hobby knowing that you have to carry large garbage bags with you every time you go flying. Back around 2005 I met three of the Tuskeegee airmen pilots at an event in Ocala. They saw my plane and remarked that they knew the actual WWII pilot, Lt. Jim Brooks and had flown missions along side him. When I mentioned the unpredictable Take off and landing results I was getting they stayed and described exactly how they did it during their training and war experiences out of the Mediterranean theater. The thing they said that was the cause of most accidents was the pilot forgetting to fly the plane after touch down, and all the way to the parking chocks.

After incorporating their suggestions in my own flying my success rate went up-and my confidence in my ability to land without damage gave me a lot of satisfaction and lowered the stress level. Now, when I go to my local field I usually devote one entire flight to approaches and landings so that when I visit out of town events I have that confidence that I can do it right. Most of the time, anyway.

sjhanc

My Feedback: (3)

orthobird,
I have both Realflight and Phoenix simulators and the P 51 performance in these simulators is different than real planes, the sim planes are easier to fly. I think the reason for this is they don't want to discourage buyers from trying their products. You can modify the P 51 in the Phoenix sim by changing the size, airfoils, drag and engine size and get a sim that more closely represents the plane you fly. I also use my JR 11x Transmitter with the Phoenix sim so that there is no change when I switch to the real model. You can set up the Realflight sim with your own trans. but if it is not a Futaba the sim will forget your settings as soon as you turn the pc off. That is a major pain when you boot it the next time. I mainly use the sims to practice low level maneuvers and touch and goes and as soon as I get a good landing I stop so my brain remembers the right way to do it rather than a dork.

orthobird

My Feedback: (1)

just ordered the Dave Brown 5.5" spinner. thank you all for the advice.

DLEVETT

My Feedback: (13)

Nice looking P-51 your building Mpizpilot.
Thanks for sharing the pics.

Dave

SWORDSN

My Feedback: (13)

The original ARF came with a spinner that attached to the back plate with 4 screws.This would crack over a short number of flights.TF sent me a replacement with 8 screws at no charge.The replacement is still going strong after 350+ flights.

sjhanc

My Feedback: (3)

rossmick,
I now have 3 flights on the slotted flaps. The first flight revealed a roll problem when the flaps were deployed. I tracked this to unequal gap from left to right. I used drill bits to gauge the gap at the root and tip of the flaps on both sides. Adjusting the gap to be the same on both sides then checking the angles solved the trim problem. I haven't tried to fly it as slow as it will go yet but I decreased the full flap deflection 10 degrees. The power needed for the landing approach is less (40%) and the approach speed is a little slower. As I get used to flying this new setup I hope to be able to land even slower with full control. I don't think I will ever go back to the stock flap hinging.

rossmick

sjhanc

Great work on the flaps. Sounds like a super modification, something I would like to try in the future.

It has been awhile since I have posted as I managed to fly my modified 60" Stik in the ground. It was total pilot error as I had not flown in two months and got a tad bit carried away and lost situational awareness. So I went down the same day and picked up the Giant Stik and put a DA 35 in it. Did some major changes in that the servos for rudder and elevator were in the tail and I moved them up under the wing in the more standard location. The blog on the Giant Stik made it pretty clear that it took several pounds of weight in the nose to get it to balance with the servos in the rear. By moving the servos forward, the tank backward, and putting the batteries behind the fire wall, I balanced without using any weight. I also used the Smart Fly board so it takes three batteries(all 2100 LIFEs), two for the board (backup) and one for ignition. Took it to the field on Friday and with a 19x8 prop I could not get the plane to not taxi at idle. I have now installed a 20x6 and will try that tomorrow, weather permitting. The DA 35 is a great engine, started right up after a choke and then started on the first flip every time there after, All the guys were amazed as their non DA engines were taking electric starters to get going. You pay more, but I think it shows.

I will now go back to work on the P-51, however, will not fly it for awhile until I get some consistent flying time in.

fytrjok

My Feedback: (2)

Has anyone put a DLE 61 in one of these yet? Assembling all the bits and getting ready to settle into a nice long bash into a B model. Would love to find out if Leo Spychalla is still producing his wonderful cowl! Already done with the gear mount/spar/shear web mods...about ready to join the wing. I did a bit of sanding on the joiner and butt ribs that will give me a few more degrees of dihedral...every bit helps! I plan on glassing, panel lines and paint. Love this plane! Splattered my last one and can't live without my "Princess"!

spitfire66

I finally have my aircraft ready to paint! It's been a long process with work and life, but it's been a great time. Now I have to teach myself how to paint!

spitfire66

I am going with an olive drab rendition of ding Hao, planning on behr latex or nelson hobby paint. I have no experience with using an hvlp spray gun or thinning paint so it may take a while with experimentation. I have read latex paint is fine for gasoline, but I'm thinking nelson hobby clear or the minway waterbased polyurethane to overcoat the plane to protect the paint from gasoline. My main concern is going to be the handpainted nose art that will be applied. I'll keep you all advised!

I have been waiting to see if dle will make a dle 61 RA version, but I'm getting restless and may go with the 55 ra. Fytrjok, I love the B-model and early in my process though about the Spychalla B conversion and cowling, but couldn't cut up my RTC. Tony Howard at Pacific Scaled Models has a new cowling you may look at as well. Looks really nice.

chris923

My Feedback: (53)

fytrjok,

Yes, Leo Spychalla still makes the cowls.

chris923

My Feedback: (53)

This is my Ding Hao, G62, Scale exhaust. I am a lousy painter, mine is mostly done in 21st century covering.

spitfire66

I can't find my answer anywhere. Is 600 grit sandpaper too fine for paint adhesion with latex paint?