I finally got to flight test my Extra with the new Saito 91 today. Man... what a difference!! With 15% Coolpower, it performs very well with almost unlimited vertical. However, when I tried 30% nitro fuel, the plane became a rocket! On 15%, it turns the 14x6 APC at around 9600 RPMs, but it turns it ~10200 using the 30% fuel. Those 500-600 extra RPMs are definitely noticeable too... I climb straight up after takeoff with no problems whatsoever. Plus, I'm even running the engine on the rich side so I know even better performance is possible.

According to info I found on the web, the FA-82a produces 1.5 HP and only weighs 16.3 ounces. The 91, on the other hand, weighs 18.3 ounces and provides 1.6 HP. Furthermore, the 82a should fit under the cowl better than the 91. Although it is slightly less powerful than the 91, I suspect it would pull the Extra around very well... especially on 30% nitro. I don't regret going with the 91 though. Since it is my third engine for this airplane, I wasn't about to take any chances on power.

I can't recall what prop I ran with the 50SX, but it definitely didn't provide the power I wanted. I know a 60 2-stroke will perform similarly to the Saito 91, but I really wanted to go with a 4-stroke.

I've just ordered the 300S .40 size ARF and hope to start building tomorrow. I had a Midwest Aerostar trainer with an OS 46AX that I pushed too hard trying to do some arobatics... the wing snapped in 1/2. So I decided to move up to something I can have more fun without the fear of the wings coming off.

I plan on using my .46 in it for now. I realize that might be a little underpowered, but I have it available now (due to the aforementioned crash) and I am still relatively new to flying.

I have a few questions for those who have worked with this plane:

This will be my first plane with a cowl. How do you access the glow plug and needle valve with the cowl in place? Do you just drill holes to reach both of these? I saw you can get a DuBro remote glow plug ignitor. Does anyone use that? If you drilled holes to access the plug and needle, can you post a pic or two?

Looking back at some previous messages in this thread and a couple others, I've read that some people are "glassing" the inside of the cowl and the landing gear pants. What is glassing? Is it just applying a substance on the surface to add strength?

I also saw a few reports of some problems with the horizontal stab cracking or breaking after flight. How prevalent is this? Are people taking any other precautions with regards to the stab?

Finally, do you have any other words of wizdom before I start construction? I appreciate any help or ideas you can provide. Thanks!

By all means reinforce the cowling or it will severely crack. I ruffed up the interior with some sandpaper. Get some light glass cloth, the LHS should have some, and lay some pieces inside. Take some 30 minute epoxy and thin it down with some alchohol. Brush the resin of the glass and let it cure. That's the way I do it. I'm sure that there are other better ways.

As for me the Saito 91 does stick out of the cowling. The valve covers and glow plug are easily reached. With a two stroke I think you would need to make a hole in the cowling for the ingiter. I would not use the remote glow igniter because you would have to take the cowling off to get to the glow plug.

<-----------------------Avitar

I also added flying wires on the tail after reading about the flight failures. It was easy to do and it helped balance the plane with that 91 on the front.

By all means be very careful when flying it for the first little while. It has a nasty tip stall that will get you that other planes do not have. Keep your airspeed up and watch the elevator input.

Today I maiden a Phoenix Models Extra 300S that I built for a friend. I am using a Thunder Tiger Pro 46 that is about 3 years old and well broken in, although not unlimited vertical this engine pulled the plane at a good pace. The plane hand no nasty habits what so ever. I yanked the elevator really hard several times to try to make this thing snap and nothing. Also on landing it had no nasty habits of tip stalling. This extra for the money was not a bad deal.

Check it out.
http://www.towerhobbies.com/products/pmm/pmma0540.html

Dave,

I have an Extra 300s with a saito 100!! WOW!! unlimited vertical at 3/4 throttle.
No mods during the ARF buildup, just built it like the manual sais.

This airplane like to fly fast, it gets mushy when airspeed is too low. I have an older extra with an OS 91 four-stroke but does not have the performance of the extra with the Saito 100 ( I call it 'Extra Strong' ).

I have been flying extra strong for about a year now and it is my favorite plane. I am running 15% nitro and an APC 14X6 prop. It is plenty strong and I always run it rich (@10200), I have no need to peak out the engine because it is so powerful that even running rich I have great performance. It does require a good chunk of rudder during take-off to keep it straight on the runway. And landing...well just keep a little speed and don't slow it down too much.

When I first put the Saito 100 in the airplane, I was doing it as an experiment in power, but I am glad I did, The Saito 100 weighs less than the OS 91 and far outperforms it. I would recommend this engine for this airplane, It may seem like too much but it really is a great combination.

Good luck with your extra, I'm sure you will have a blast with it.

MR G

AQ500,

Thanks for the tips.

Joe

I use a remote glow igniter for my Extra, which cleans up the look of the cowl. I have to remove the cowl after each flying session to add after-run oil, which could be avoided by cutting a hole in the cowl. It really depends on how much you want to avoid having additional holes in your cowl. I run the wires from the plug to a Futaba-type J-connector near my charge connector. My flight box has a special igniter output so I use that instead of the regular handheld glow plugs. Still... adding a remote glow igniter means extra holes in your firewall and extra wires; I'm not sure I'd do it again.

My stab is just fine, and I haven't applied any reinforcement to it. I think you just want to be really careful when cutting away the MonoKote to avoid cutting the balsa which will weaken it. Adding flying wires is another good way to add strength. I glassed the joint between the two main wing pieces however. Snap rolls tend to put a lot of stress on the wing... though I doubt it would fail without the glass. Adding it just gives me 'warm fuzzies.'

I also glasses the inside of my cowl. I had one rather nasty crash a while back, which cracked the cowl (and destroyed the wing). Since then, the cracks have become worse. At this point, the fiberglass is the only thing holding the cowl together. I'd highly recommend this step but try to go light on the epoxy as it adds weight. Also, you might consider glassing the inside of the wheel pants. They will probably crack much sooner than your cowl. Or... you could fly without them altogether like me. They are generally more trouble than they are worth. Stan's Fibertech makes fiberglass cowls and wheelpants for a variety of ARFs including this Extra. I plan to order some from him when my ABS cowl finally gives up the goat.

On engines... when you're learning to fly this plane, the 46 should be fine. However, if you're like me, you'll quickly become frustrated with the lack of vertical performance. Flying the Extra with the 91 4-stroke is a completely different experience than with the 50SX. In fact, I find it much easier to fly with more power despite the added weight. I can't imagine what a 100 4-stroke would be like. If you're into 2-strokes, a 60 should provide a lot of pull.

Finally, as others have said, keep up the speed with this airplane when landing. It does tend to tip stall when you get too slow. Also, stick to the recommended throws on the control surfaces. I fly high rate all the time, but when you're getting used to aerobatic planes, the low rate setting is a must. Also, even though the travel on the elevator seems small, it's sufficient for flying this airplane.

Have fun.

Dave

P.S. Don't forget to mount the little plywood screw reinforcement to the bottom side of the wing before adding the belly pan. The instructions don't mention this step and removing a belly pan that has been CAed into place is a pain in the butt!

The cracked horizontal stab had nothing to do with cutting away the monocoat.. If you run your fingers across the stab you can feel the center section is quite solid and seems to be strong enough.. It is at the end of the "solid" portion, that mine cracked... No Monocoat cuts out there... I sheeted mine to fix it since I had to teke the covering off to repair it anyway... I checked the differance between the 40 size and 60 size kits. One of the big differances was the sheeted stab on the 60 size kit. Flying wires etc should work just as
well if you catch it before it cracks... My next one will have the wires... Just my experiance with this great plane :-]

HELP!

I just got this arf version of the .40 extra 300s by gp and i cant get the servo wires out of the wing. I did what the instruction say and i tied the servo wire to the string and mounted it on and hmnnnn i cant find the string on the other side to fish it out? WHAT DO I DO?? someone please help me. Thnx alot,

STeve

Please help me

i cant get the string on the other side whereits supposed to be fished out as the manual says, what do i do?

Please help,

Steve

Tie a 4-40 nut to a piece of cotton, and, holding the wing up, let gravity rattle it down through the holes in the ribs, from the servo end by shaking the wing.

Use a piece of wire with a hook bent on the end of it, throught the hole in the center of the wing. You are bound to hook the thread in the end.

-David C.