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Old 08-10-2008 | 12:16 PM
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BMarks4645
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From: Alpharetta, GA
Default RE: Nitroplanes Extra 500

I took mine out for the first flight on 8/8/08. I have a Saito 82A installed. I also fly pattern but thought this one might turn a few heads at the field. My experience:
• Manual is OK for experienced builder, novice may experience some problems.
• My finished weight (digital scale) is 8.7 Lbs not 11 Lbs as stated in Nitros site, nor the 6.2 Lbs as stated in the manual. The 6.2 is probably without servos, etc. As I said I fly pattern and am very conscious of adding weight. I don’t know how I could have saved any weight, although the Saito is a little heavier than 2 Stroke.
• I installed the gear first in order to have a stable platform. I found the gear to have a left and right design, it will be apparent if you have them reversed. I added 1/8” light ply spacers under the gear to keep them level and avoid cutting into the glue build-up for the gear blocks.
• I epoxied my wings together. Be aware the supplied dowels are too loose for the predrilled alignment holes, be careful here. Installing tighter/larger dowels will be a problem if dowels are pre-glued in one side and are too long, wings won’t align due to dihedral. Keep the unglued side minimum length -1/4-3/8”. (You may have a better solution)
• Cutouts for wing servos were larger than my JR/Spektrum std size servos. I added balsa fillers and painted them black.
• I use DuBro pinned hinges with canopy glue, so I can’t comment on supplied hinges but thought they were clever with glue slots, looks like a good idea.
• I stretched a string between the centerline of the dorsal fin and the center of the firewall to establish a centerline for the wing and marked it accordingly. I found that I had to add hardwood (basswood) dowels on the underside of the front wing hold-down bolt holes because the preinstalled ply between the ribs was flexing and may become weak or broken over time. I then made/installed rolled paper tubes with CA on the top side to act as guides for the hold-down bolts so that they wouldn’t get lost inside the wing cavity. I painted these black.
• I used the supplied blind-nuts for the wing hold-down bolts, I don’t like these, but, Oh well! I fitted ¼” basswood blocks with countersunk holes to accept the goofy design of the blind-nuts and epoxied these to the underside of the saddles. I thought the 1/8” thickness was not enough for me and I also wanted to get the bolts to go vertical into the wings.
• I pre-fitted the wing tips. I had to sand in some spots and add 1/32” filler strips in others to maintain level surfaces. I added micro-balloons to the epoxy to fill any gaps and painted the joints silver. I also had to add 1 1/8 oz. of weight on right wingtip to counter-balance the heavier left tip design. (I installed the weight and wing tips as the last item after engine and everything else was installed so that I could balance the plane laterally).
• For the elevator servo, I epoxied small basswood blocks inside the vertical fin to accept servo screws.
• I found the elevator installation to be a bit challenging in terms of keeping the two stabs level, maintaining the same incidence as the wing and keeping an equal measurement from the tip to tip alignment with the wing. I installed the wing first as reference and blocked the plane level. I then put the incidence meter on each stab (for front-to-back) incidence and marked each stab fairing with a paper template so that I would know where to drill the holes for the carbon-fiber dowels and alignment pins. (After all this I still had to enlarge the holes somewhat on one side for final alignment, you may have a better solution). I had to sand the fairing surfaces before installing the stabs as indicated in step #1, it took a fair amount of sanding. I was careful but didn’t get both exactly straight and level, top to bottom and front to back. So I mixed microballoons with the epoxy and glued them in place checking with incidence meter front to back and left to right and taped them in place until glue set.
• My solution for installing the elevators was to cut a slot in the vertical fin instead of drilling a hole for the steel wire connector. I slid the wire into the slot, taped the elevators to the stabs just below the wire and marked the location for the wire holes. I then drilled the holes, trimmed the slots and added thin CA to harden the holes. I then epoxied the wires into the elevators, slid the assembly into the slot and taped them in place until the glue set (using wax paper to avoid gluing to the stabs). After this dried I removed the assembly and installed the hinges as usual. I did not fill the slot and it looks OK to me, but you may want to fill and paint it.
• The fitting and installation of the hinges for the rudder into the vertical fin when using the supplied hinges are suspect to me. Not enough of glue surface. I used the pin hinges again with epoxy and turned the plane on its tail letting the epoxy settle into the hinges to form a thick glue bond on the inside of the fin. I wasn’t able to pull the hinges loose. I could not use the pre-installed pushrod guide for the rudder. Mine was poorly installed. So I bypassed theirs and had to install a new one with plenty of movement for the rod where the rod exits the fairing at the back.
• I normally use Fults dual nose gear but opted to use the supplied gear. It’s either too short or the main gear is too long. I don’t favor the extreme nose-down attitude.
• I didn’t use the supplied motor mounts so I can’t comment on them. I used Great Planes adjustable mounts as I had a pair available.
• I had to fuss with the fitting of the cowl relative to the position of the motor mounts, alignment of the spinner and mating of the cowl to the fuse. Be careful if you trim the length of the cowl as it becomes a smaller diameter to mate to the fuse. My cowl had to be tilted downward to align and I had to sand the bottom of the firewall block considerably at the bottom to get the cowl to align with the spinner. This left a gaping hole between the glass fuse and the firewall block so I filled it with a considerable amount of epoxy-microballoons.
• The last thing I do is install the battery for balance. I made provision for two locations based on the conflicting info in the manual, 5.12” and 4.88”. On my plane there is a 3” difference for battery location using a 5 cell NiMh.
• There is no provision for containing the fuel tank. I installed two “J” bolts with blind nuts and hold the tank in place with rubber bands stretched across the back side of the tank. I use clear silicon at the front. I also cut two teardrop vents in the top of the cowl as my engine seemed to be running a little hot.
• Covering/ finish. The covering was wrinkle free but the wood surface beneath is not good.
• The first flight was OK. Power to weight is less than I like. I ran a 13-8 APC and it struggled a bit on take-off. I had no expo dialed in and at 30 percent travel I had my hands full. I didn’t keep it up long enough to dial in trim. The landing was better than expected. I brought it in rather fast since the position of the elevators doesn’t get much if any propwash. I didn’t want to stall. I want to try a 12-8 for more RPM, so I didn’t try to go up again on Friday. We should be back at the field today for another flight. This time I have expo and have reduced the travel of the ailerons. I also have flaperons initiated with a guesstimate of down elevator dialed in. I’ll save that for last.
• I didn’t know what to expect for a 60 size scale ship with a glass fuse for $155.00 (incl. shipping).

This is my first Nitro model and I suspect from what I have heard about Nitro this plane is probably not a good gauge by which to judge Nitro. This is not the best ARF I have assembled but I suppose one must allow for the price level. It did get a lot of attention at the field, but I hope I get more impressed with the flight characteristics at the next session. I think power to weight is the biggest issue. I don’t like to overpower my planes. I like them to fly on their wings. Hope this helps with your build.
Bob Marks AMA 4645