BTW, I dropped by to ask what size plane can use this motor ?

Originally Posted by Chophop

If a small light EGT probe can be found, a mixture control can be made. Find the optimum EGT (exhaust gas temperature), program a PIC to monitor the EGT and throttle setting then position a servo to adjust the mixture. It has to be done well or can be more problem than help. Probably best for a larger motor and plane. A nice winter project, and a high EGT detection can initiate an alarm that an engine meltdown is on it's way far ahead of the failure.

That is a pretty cool idea. I like it. Something to think about over the winter.

Actually for your other question any .40 to .45 size plane would be suitable. Some larger planes such as trainers with a flat bottom airfoil could be larger in size though. But the .50 size planes may be too big though they may fly but they'll feel underpowered. The old more or less vintage .60 size planes are smaller than today's modern .60 size planes, and those would work Ok too. The little 9cc engine runs about the same as my old baffled .60 engines do. It turns a 11x7 to 11x8 prop at around the same RPMs. A good example of this is the Top Flite Contender plane, it would fly fine with the little gas engine.

I have one engine in a Big Stick .40 (Ugly stick type of plane).
Another engine is in a Escapade .40.
Then my third engine is in a .45 size Pattern plane, I just got it all setuo, but I haven't flown it yet. This plane isn't much smaller than the Phoenix ARF though. I might have gone with the Phoenix too, but I already have several of these .45 size pattern planes left over from the good old days to use up still.
Now the engines being basically glow engines converted to gasoline spark ignition, tend to not have lots of cooling fins on them, so using the engine in a cowled plane might need some care taken for airflow for cooling, But since I have been torturing the poor engine in the Ugly Stick this summer, maybe it isn't a big thing to worry about.
So that might give you some ideas as to its usefulness or not.

I'm thinking maybe a 3 - 4 lb sport aerobat with a 50 - 60 inch wing ? Looks good, I think I can get it in and out of a 125 foot landing strip. Batteries are great but I'd like to push full or near full power for 10 minutes. This could probably do it.
Plus I keep charging my batteries and the wind changes direction and I can't fly my larger planes out of this field .

Yeah that is the ticket. If you use a LiFePo4 receiver pack and a Tech Aero Ultra iBec, you can save a significant amount of weight as you don't need a really large 4 cell or two separate battery packs then. I flew the Escapade with a 5 cell RX pack and a 4 cell ignition pack and it worked OK, but it really livened up a lot with the LiFe pack and iBec unit as it saved a decent amount of weight, If the RX and servos are rated for 6v they'll work fine with the 6.6v liFe pack. Plus you can charge them back up faster in a hour or so, and they have a really slow self discharge rate as well. It worked out so well that I put a Life pack in my .45 Pattern plane too. The iBec plugs into a Aux channel on the RX and you can turn it on and off, so it serves as a remote on/off switch too.

The CDI ignition module draws about 350ma to 600ma (WOT) so power consumption isn't really much worse than using standard size servos.

Originally Posted by earlwb

Yeah that is the ticket. If you use a LiFePo4 receiver pack and a Tech Aero Ultra iBec, you can save a significant amount of weight as you don't need a really large 4 cell or two separate battery packs then. I flew the Escapade with a 5 cell RX pack and a 4 cell ignition pack and it worked OK, but it really livened up a lot with the LiFe pack and iBec unit as it saved a decent amount of weight, If the RX and servos are rated for 6v they'll work fine with the 6.6v liFe pack. Plus you can charge them back up faster in a hour or so, and they have a really slow self discharge rate as well. It worked out so well that I put a Life pack in my .45 Pattern plane too. The iBec plugs into a Aux channel on the RX and you can turn it on and off, so it serves as a remote on/off switch too.

The CDI ignition module draws about 350ma to 600ma (WOT) so power consumption isn't really much worse than using standard size servos.

I use the same set up on all of my smaller planes up to 30cc and it works great. Highly recommended for reducing weight.

Hi everyone,

After receiving the new spring, testing learned that the engine still ran lean througout the entire rpm-range. Switching back to normal exhaust pressure (without pump) did not help, the engine bogged down just after take-off. A new glow plug did not help either. Performance got worse and worse. The engine died immediately when the plane is held vertical (nose up). I decided to go home and defueled the tank though the clunk line. After removing the wing I noticed that the tank was still half full. Dissasembly of the tank learned that the brass clunk tube that goes though the rubber stopper was completely broken in two. The jagged edges of the fracture were typically fatigue fractures, with hairline cracks in some corners. I replaced the brass tube with a new one. To be continued.

Best regards,

Here are pics of the 9cc engine on my old style pattern plane. It is a fairly large plane with a swept back wing sporting a 59 inch wing span. The day was quite windy and gusty today, and on its first flight of the day, the muffler came loose, and the wind turbulence either had a downdraft or wind shear effect, causing a hard landing of course, and I wound up tearing the nose gear loose on it, and the wing hold downs came loose. So I'll fix that and have it out again soon. It was interesting in how the muffler coming loose really affected the performance of the engine and it starting missing a lot. So I didn't think the muffler would have had that much of a effect on it. Anyway the engine ran really good and the plane didn't feel underpowered at all, it sort of felt just about right actually.

Bit of a shoe horn job Earl but looks good.

Thanks, yeah it was a bit of a tight fit. But with our modern equipment I can use velcro to hold things down to advantage and not need a lot of foam padding.

Our club had a club members only fly in at our club field on Sunday. Only myself and three others braved the windy day. 20mph with gusts over 25 too. We have a tree line on the West end and farther away on the East and North sides. I was the second one to fly that day. I didn't expect the winds to have some kind of a dead zone or downdraft, wind shear or something if I came in too close to the West side tree line. My plane tends to be a windy day plane as I usually fly it in somewhat hot for landings anyway. But that didn't help it any.
Anyway it was a wicked cross wind takeoff and landing day though. I flew the Escapade .40 with the 9cc engine fine that day by coming in farther over to the right and landing farther down the runway more.

Here is a short video clip, where I flew the plane, up until the muffler came loose and the engine started misfiring and the plane got caught in a bit of bad air on the landing. The plane's predecessor like it, had a Saito .80 in the nose so although one might think it is nose heavy, it isn't.

Here is the video with the hard landing for your crash pleasure. It looks worse than it turned out to be.

Flying the NGH 9cc engine in my .45 size low wing pattern plane (2 min 23 sec)

Earl that's one mean ouch , lucky you didn't do more damage. Other than the landing the plane flew very nice with the GT9

As for the in-flight mixture control, using an EGT shouldn't be to hard except getting the biasing right (Lean/Rich). There are EGT's small enough or you can make one, op-amps for the error control, and 555 driver circuit for the servo. I'll have to put this one on my bucket list.

Ray

Thanks.
Yeah at first I was afraid I would be tunneling back into the storage shed to get another one of these planes out of storage to use. Fortunately the damage isn't too bad. So it'll fly again soon. I need to wait on an Eccentric steering arm to be mailed to me for the Fults nose gear though, as it got broke off in the hard landing. Or I go conventional on the nose gear instead.

I did like the way the engine pulled the plane around good too. It seemed to have plenty of power for it.
I didn't even have to trim the plane any either, the trims were all good to go right off the bat.

Hi Guys, have just received this motor with the idea of putting it into a VQ models Spacewalker. Intend to do the recommended mod with the B&S pump kit, but what size fuel nipples do I need for increased fuel pressure mod and where can I get them ? (preferably in Oz but no great deal if they come from O/S).......Cheers

Dubro 8/32 pressure nipple used on the glow mufflers will do. You can get them from Tower Hobby or some sellers on ebay. In Australia I would say Modelflight, Nitrodude, Rcheadquarters etc probably stock them.

Many thanks, Brace, have taken note of your summary of modifications and will be interested to hear what you do about a carb improvement if you go ahead with that. I was considering a fuel mix of high octane with Morgans Coolpower blue at 15/1. erlwb tells us these things need a lot of lubrication. I would appreciate comments from anyone on this thread.....Cheers

Well, I ordered one of these little motors, I may be overly optimistic but I hope that since its fresh stock from HobbyKing, that the manufacturer has incorporated some fixes to the issues mentioned in this thread.