KJKimball

A question for those with the non functioning gear door issue. We (my son is KJKalzone who posts here) did NOT have the problem. I read in one of the posts above that someone with main door issues had not tried the tail wheel yet. Kal always had the tailwheel connected to the controller and sitting on the center section while working on and setting up the main gear and doors. Is it possible all 3 gear need to be plugged in for the doors to function due to a sequencing protocol? As far as I know, Kal did not try our gear without the tailwheel installed. Just a question that popped into my head when reading the posts here and worth trying if you have not plugged in the tailwheel. My gut is that it doesn't matter about the tailwheel being connected but I am curious.

Kevin Kimball
www.pittsmodel12.com

BarracudaHockey

My Feedback: (11)

The controller gives you the option of whether or not a tail wheel is present, and whether or not gear door servos are connected.

fhollahan

I am still deciding on an engine for the H9. My flying experience is with both DLE and DA in my 3D planes. I have had good luck with both for the most part. DLE is a better value based on my experience to this point. I went to a LHS yesterday to look at and measure a DLE-55RA with the stock muffler. It looks like the muffler is actually farther back then the carb and very close to the carb. When I think of getting shorter (minus 12-15mm) standoffs than the current stock ones it looks like I would have a significant problem with the muffler and firewall clearance. I am now leaning towards a DA-60 or DLE-61. The DA would fit I believe with the stock standoffs DA supplies and the DLE would need shorter standoffs but in both cases a wrap around Jtec pitts would be well below the firewall. I think Jtec has a "slim" wrap around designed for the TF-P51 that might work. Has anyone tried to configure the DLE-55RA yet?

ForcesR

Fhollhan, the DLE 55RA muffler will not come in contact with the firewall. The photos show my TF P-51 with the DLE 55RA mounted with the standard standoffs. If 12mm shorter standoffs are used as is needed on the H9 P-51 installation, there will be 9mm distance between the muffler and firewall. The DLE RA muffler is not mounted further back than the carb, the back of the muffler aligns with the mounting bolts of the carb as shown in the photos.

Roger

KJKimball

Ah. OK. Kal wasn't home today for me to ask so that is why I posted the thought.

kalzone

if you don't turn off the tail wheel the doors will move and the gear will not move at all.

fhollahan

Roger, thank you for measuring. Looks like it will be very close to the firewall and the outer edge of the H9 wall is extended 10mm out further then the mounting surface. Will be very tight with heat very close to the wall once the standoffs are shortened. Something to think about.

ForcesR

The H9 60cc P-51D engine firewall to front of cowl is 158mm. The DLE 61 with standard standoffs mounting length is 172mm, therefore shorter standoffs will be required.

Roger

fhollahan

Roger, Thank you for the additional info. I went and measured my H9 to the cowl and I get 158 mm (~6.25") from mounting wall to edge of cowl. Not sure why we are getting different numbers unless I am not measuring correctly. I was targeting roughly 160 to 162 mm to the back of the spinner plate to give me a nice gap. My wrap around mufflers in my other planes all drop well below the firewall and in all cases are not close since the stock standoffs work fine. The challenge for my wrap around mufflers is getting them completely tightened down in the first several flights and getting one that is "slim" on the side to avoid cutting the cowl.

Frank

ForcesR

Hi Frank, you must have read my previous post before I had a chance to correct it. I realized after I posted that 168mm was incorrect and 158mm was the correct length. Sorry about that mistake, unfortunately my dyslexia kicks in every so often and I don't realize it sometimes until after I have posted. You are correct, 160 -162mm would be an ideal clearance between the spinner back plate and the cowl.

Roger

fhollahan

Roger, no problem, I appreciate all the input and these threads are great. Hope I can get moving faster on my build and give back to the thread. All I have is the canopy together at this point. I am down to either using the DLE-61 or the DA-60. A matter of $$ to some extent . Frank

ForcesR

I wonder why H9 engineering chose 158mm distance between the firewall and front of the cowl for engine depth installation? They should have placed the engine firewall back a further 20mm or 25mm to make the engine mounting depth 178mm or 183mm. This would have saved a lot of fustration in choosing an engine with standard standoffs. The TF P-51D engine firewall is 193mm in depth for engine installation, so much easier to select an engine for the TF. For example the Kolm EZ 65cc will fit in the TF with no modification of the firewall where as the H9 60cc P-51D firewall requires major surgery, it has to be moved back.

Roger

marksp

My Feedback: (9)

Yep, I measure 158mm from firewall to outside edge of cowl as well. And like some, am uncertain about engine selection.

I've pretty much eliminated all twins and/or 4-strokes, which would've been my first choice, but no apparent options that fit. I've had great personal experience with DLE. Never had, but highly regard DA. Dig the EME starter which works well on DLE. Have a few flyers at local club with positive experience with EME (V2) engines.

Hmmm....

Lifer

My Feedback: (1)

Didn't they design it around the fuel injected engine they subsequently withdrew from the market? I suspect its dimensions are spot on for the Mustang.

KJKimball

No stand offs is the most stable installation. Longer stand offs are not as stable as shorter ones. The firewall is set for the stand offs used for the recommended installation. There is a hole in the firewall to allow the carb to poke aft thru the firewall and set the prop flange at the proper location while keeping the stand offs as short as possible. The 172mm engine set up with stand offs seems like it could be used with shorter standoffs to set the prop in the correct location since the stand offs in the diagram posted above are long enough to not have the carb poke thru the firewall. Pretty simple determine what length stand offs are required for your selected power plant and then buy them. After that, clear the opening in the firewall to allow your carb to pass thru.

I know there are variations in dimensions, carb location, muffler choices, etc. between the engine companies. If you choose to install a motor NOT planned for in a kit, or your personal car or a ski boat, you will have to make changes to suit your needs. For us, we are putting the Power 360 electric in the Mustang like we did in the Hangar 9 Corsair. So, most everything from the wing leading edge forward will change internally. Like you , we decided to stray from the design intent and it adds some work to the project.

vertical grimmace

My Feedback: (1)

It is very simple to fabricate appropriate standoffs for an exact fit. Choose your engine, and make stand offs. DA engines do not even come with them, or they did not used to.

fhollahan

On the DA-60, 50, and I believe 35, they supply a multi-layer block of plywood that is about 1 inch to start. You remove layer(s) down from there to fit your need. Probably a better mount then standoffs I would think. My 85cc Yak from AW came with one but that one was provided by AW, not DA.

pkoury

My Feedback: (7)

Best method I have found is to use bead chain. Insert it into the wing opening, hold the wing vertical and shake it around a bit until the chain comes out at the center section. The chain is also really good at turning ceiling fans off and on.

Lifer

My Feedback: (1)

The bead chain is an excellent idea! Thanks.

ForcesR

Lifer, I forgot about the fact that the Evo 62GXI was withdrew; you are absolutely correct with what you stated, "I suspect its dimensions are spot on for the Mustang" The engine mount depth for the H9 60cc P-51D from the firewall to the front of the cowl is 158mm See page 14 of the attached Evo 62GXI manual, engine mount to prop thrust washer is illustrated at 129mm, add 33mm standoffs or shims/spacers and you have 162mm depth from the firewall to the prop thrust washer

I can see clearly now, IAW 1970's hit song

Roger

GR7Racer

Regarding the gear/door issues. It took me a while to figure out that both main gear needed to be connected to the controller for it to work properly. You also need to have the main gear in gear slots two and three. The first slot is for the tailwheel and you can and should turn that slot off in the controller if you don't have it plugged in. The other thing that threw me off is that when you change a value in the controller, you need to press save right after you make the change. You'll see a message come up on the controller saying that it has saved the changes. So, the first option is doors so press value until the asterisk is next to P-51 and then press ok, then press the save/test button. Do this for every value that you change...at least that's what I did and it worked. If you are using the recommended Spektrum servos, and Hangar 9 servo arms, then the values listed in the mustang manual for the door settings inside the controller work good. If not, you'll need to put in some values to experiment with. When you have entered the values and saved them, you can scroll through the mode button until you get to test and press the test button to try them out. Doing this from memory, so hopefully this is all right.

Another thing that was giving me trouble with the electric gear was the rib inboard of the mechanism which has a cutout for the strut to fit into when the gear is retracted. This cutout wasn't deep enough on my model and needed to be made deeper. The strut would press against it and not allow the gear to unlock when I tried to extend them. You might also install the small white shims that come with the gear underneath the mounting plates of the gear to gain more clearance. These shims have some peel and stick adhesive on them so you can stick them to the gear and they will stay in place while your are bolting them in.

A friend of mine has a set of Sierra gear and we compared dimensions of them to the Eflite gear, and they look like they will fit with minimal re-work. Since the Sierra and Robart gear are similar in mounting configuration, I suspect they will work as well.

I had my inner gear door hinges come loose on my mustang after a few flights, so I would also recommend sanding inside the hinge slots inside the wing with some sandpaper or a thin file to roughen the surfaces in there. If you already have them installed, put a couple of #2 sheet metal screws through them to help hold them in place.

For those of you with DA 50s and 60s, the JTEC compact wraparound pitts muffler that they make for the TopFlite mustang will work nicely in the H9 bird.

KennyMac

Johnny_Zero

My Feedback: (44)

Thanks so much for this info GR7Racer. This will help all of us very much.

GR7Racer

No problem. Manual on the gear and controller isn't great. Had to sort of figure it out by trial and error.

GR7Racer

Someone also asked about adding nose weight for CG. I had to add about 8-10 ozs to get it to balance. It was recommended to fly it at the forward CG measurement in the manual, and I like the way it flies there and don't plan on changing it. I installed 2 x 2200 mah Spektrum LiFe packs under the hatch just in front of the wing. I used another 2200 mah LiFe under the hatch on the motor box for the ignition. Throttle and Choke servos are next to the fuel tank and RX is under the cockpit floor. If you are setting this airplane up with the servo operated gear doors, take some time to keep the area just in front of the cockpit floor clear of any components or wiring. The servos and servo mount for the doors use up the entire width of the fuselage right there about an inch or so in from the wing saddle. I struggled getting some wires passed through this area without them getting hung up on the servo arms as they operate.

KennyMac

Johnny_Zero

My Feedback: (44)

I may have missed it.....what engine are you using?