Mitch G
Jun 16, 2003, 01:00 AM
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<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/intro_plane_pic.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/intro_plane_pic_t.jpg"
width="200"></a></p>
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<strong>Wingspan:</strong>
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47" (1210 mm)
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<strong>Wing area:</strong>
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338sq. in. (21.8 dm2)
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<strong>Weight:</strong>
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Specified: 16-18 oz (450-500 g)<br>
As built: 22 oz (628 g)
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<strong>Wing Loading:</strong>
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As built: 9.4 oz/sq. ft (28.8 g/dm2)
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<strong>Motor:</strong>
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Mega 16/15/5 and<br>
Mega 16/15/7
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<strong>ESC:</strong>
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Jeti 18-3P Gold Label
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<strong>Radio:</strong>
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Hitec Electron 6 RX<br>
HS-55 servos
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<strong>Available From:</strong>
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Northeast Sailplane Products (<a href=
"http://www.nesail.com/">http://www.nesail.com</a>)
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</p>
<p>
<big><b>Introduction</b></big>
</p>
<blockquote>
<p>
I had been flying a sp400 rudder/elevator sailplane for the past year, but I was getting a
bit bored with it. So, I started to look at electric sailplanes with ailerons figuring I
could have a bit more fun in terms of maneuvers and also a bit of fun playing with things
like spoilerons and flaperons. So, when I was given the opportunity to review the TopModels
Navaho from Northeast Sailplane Product (<a href=
"http://www.nesail.com/">http://www.nesail.com</a>), I gladly accepted.
</p>
<p>
The Navaho does not sport a long sleek, high aspect ratio wing like some other sailplanes.
Nor, does it have the latest high-tech airfoil and wing construction. Instead, the
Navaho has a low aspect ratio (6.2), relatively short ,1.2 meter, built-up balsa wing based
on an s4083 airfoil. No, the Navaho is not sexy. Instead, it offers a simple design, with
light wing loading, easy transport, and quick assembly in the field. In other words, it's a
great grab-and-go electric sailplane for hunting lift whenever the opportunity presents
itself.
</p>
</blockquote>
<p>
<big><b>Kit Contents</b></big>
</p>
<blockquote>
<p>
The Navaho is an ARF. It is a relatively quick-building plane with all the hardware
included. Upon opening the box, one sees a fully covered wing and tailfeathers, with a
fiberglass pod and carbon fiber boom. All the covering (which is Oracover) was done very
well and the fiberglass fuselage pod was very well molded with no blemishes.
</p>
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<a href="/articles/liftzone/2003/jun/navaho/kit_contents.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/kit_contents_t.jpg" width="200">
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The kit contents.<br>
It looks like a quick build.
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<p>
Although the parts were all well executed, I was a bit concerned about the instruction
manual. It is presented entirely in pictures/drawings with no text to help the builder along
the process. I like to have a bit of prose to go along with pictures. But, I found that by
going through the manual a few times before sitting down to build helped me assimilate the
instructions. And, hopefully, this review will help add that missing narrative for any other
future Navaho owners.
</p>
<p>
<b>Deviant Behavior</b>
<br>
When doing a review, I don't like to deviate too far from the stock setup and
instructions. However, there were a few obstacles to achieving this goal for the
Navaho.
</p>
<p>
First of all, I no longer have any brushed sp400 gear. So, from the start I knew I would be
using a brushless setup. My previous sailplane had flown on a direct drive sp400 motor
spinning a 6x3.5 prop on 8x1100HE cells, then a Mega 16/15/5 swinging the same prop and
using the same cells, and then finally on a Mega 16/15/7 swinging a 9x5 prop, again on the
same packs. From this experience, I knew that the 16/15/5 was a very close substitue for the
brushed sp400. It basically spun the prop at the same RPMs, but did it at a lower current
draw (i.e. it was more efficient). And, I knew that the 16/15/7 setup was simply fabulous at
pulling the plane to altitude. So, I decided I would fly the Navaho on both the 16/15/5 and
16/15/7 power systems. The former would provide a good example of how the plane would
perform on the stock setup, and the latter would be an example of a more spirited setup.
</p>
<p>
The other problem I had to address was that the instructions show a non-standard (for me at
least) battery configuration using a 7-cell pack. Well, all my packs for this size of plane
are 8-cell packs side-to-side configured. So, based on the configuration and placement of
the pack in the instructions, and based on some posts on the E-zone, I was pretty sure I
would end up with a nose-heavy plane. One approach mentioned on the E-zone to mitigate this
problem was installing the rudder/elevator servos in a tandem configuration near the nose.
This then allows the battery pack to be slid well into the aft end of the fuelseage. Well, I
thought that changing the servo installation was a bit too radical for a product review. So,
I decided to just build the plane pretty much in line with the instructions, and deal with
the nose-heavy condition if necessary. As it turned out I only had to add about 0.5oz to the
tail.
</p>
<p>
Therefore, to summarize, I did deviate from the stock plane in terms of the number of cells
- 8 vs 7, and in terms of the motor - a brushless sp400 size vs. a brushed sp400. However,
the Mega 16/15/5 is such a close replacement for a standard sp400 in terms of power and
RPMs, that I expected the flight tests with this motor would closely match flights with a
brushed sp400 motor. But, I did not deviate in terms of radio installation. I installed the
servos and electronics pretty much as per the instructions (although putting them as far
back in the fuselage as I could) understanding that I would likely have to add weight to the
tail to get the plane to balance.
</p>
</blockquote>
<p>
<b><big>Assembly</big></b>
</p>
<blockquote>
<p>
As I was working on the steps given on page 3 (installing the r/e servos and
receiver), I happened to think about how the wing is held in place and realized that had I
finished page 3 and glued everything in place, I think I would have had a heck of a time
installing the blindnut and plate for the wing bolt. So, I changed the order of the
instructions such that I did Page 6 before Page 3. The rest of the pages were left in their
original order. However, as you will read below, I don't think it would be a bad idea to
even do Page 6 before Page 2 to make rigging the tail feathers and boom easier.
</p>
<p>
<strong>Page 1 (~30 minutes):</strong><strong><br>
</strong> Page 1 is pretty straight forward, but there is a mistake in the instructions
regarding the installation of the elevator control horn. Assuming you installed the rudder
control horn as per the instructions, the instructions for the elevator control horn are
incorrect. Following the instructions would result in the elevator control horn being on the
same side of the plane as the rudder control horn which could cause interference between the
two. Instead, install the elevator control horn on the other side from that shown in the
instructions to avoid this problem.
</p>
<p>
The rest of the instructions on Page 1 are fine and easily followed. However, check the
holes in your control horns before gluing them to the control surfaces. The holes in my
control horns were all too small for the included control rods. It's much easier to ream out
holes before the horns are attached to the surfaces.
</p>
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<a href="/articles/liftzone/2003/jun/navaho/fin_square.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/fin_square_t.jpg"
width="200"></a>
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Squaring the fin to the stabilizer while the epoxy sets.
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</p>
<p>
<strong>Page 2 (~45 minutes):<br>
</strong> Page 2 is all about gluing the tail to the boom and gluing the boom to the pod.
Attaching the tail feathers to the boom was not too difficult. I used a Dremel to flatten
the top of the boom as per the instructions. And, attaching the tail was a matter of
applying epoxy and then holding the tail and boom together with my hands until the epoxy
set.
</p>
<p>
However, attaching the boom to the pod without any jigs or other aids other than my ability
to line things up was a bit daunting and a rather non-ARF like step. But, I had no choice.
So, I inserted the boom into the pod the appropriate distance (as indicated in the
instructions) and then propped the tail on a couple of rolls of 1" tape. This appears to
give the right vertical angle of boom to pod - I believe. Then, I lined up the horizontal
boom-to-pod angle. Once I was convinced that gluing it like this would be fine, I applied
epoxy and made sure everything was lined up correctly as before and let the epoxy set.
</p>
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<a href="/articles/liftzone/2003/jun/navaho/tail_propped.jpg"><img
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</a>
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Tail propped on rolls of tape in preparation for boom-to-pod attachment.
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<a href="/articles/liftzone/2003/jun/navaho/straight_boom.jpg"><img
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<p>
Side shot of boom and pod attached.<br>
(Red line added to show boom - hidden behind the line - is at the correct angle.)
</p>
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<p>
Unfortunately, I got a little cocky and didn't think I needed to have the wing on the plane
when gluing in the boom. Instead, I figured I could eyeball it using a triangle. I was
wrong. As a result, my tail is a touch off kilter from the wing when looking down the
length of the plane. It's not the end of the world and the plane flies fine, but it is
annoying and I'm mad I wasn't more diligent in this step. So, let this be a warning to you.
In fact, it may even make sense to do Page 6 before Page 2 so that you can officially attach
the wing and set the boom orientation before the epoxy sets.
</p>
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<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/squaring_tail_feathers.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/squaring_tail_feathers_t.jpg"
width="115"></a>
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The wrong way to square the tail feathers.<br>
(What was I thinking?)
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</p>
<p>
<strong>Page 6 (~30 minutes):<br>
</strong> Regardless, if you didn't do page 6 before Page 2, you will want to do Page 6
now so that you'll have enough working room to put the blindnut and bolt plate in position.
If you do page 3 before page 6, I think you'll find it rather challenging to maneuver these
parts (parts 2-31 and 2-3) in position for gluing. Overall page 6 is not too hard. Attach
the dowel to the wing, and drill the front end of the wing saddle to accept the dowel. Then,
position the wing correctly by measuring the distance between wing tips and horizontal
stablizer tips. Once satisfied with the position of the wing on the pod, drill through the
predrilled wingbolt hole near the trailing edge of the wing and into the pod. Then, assemble
the blindnut and bolt plate and glue it into position.
</p>
<p>
<strong>Page 3 (~20 minutes):<br>
</strong> Now that the wing bolt parts are glued into place in the pod, one can direct their
attention to positioning the equipment that goes in the pod. Page 3 starts that process by
getting the pod ready to accept the motor and by getting the tail boom ready to support the
control rods and sleeves. The steps on page 3 are not difficult. I would suggest, however,
not bothering to actually install the motor at this point since it'll just get in the way in
later steps.
</p>
<p>
<strong>Page 4(~60 minutes):<br>
</strong> The main goal of page 4 is getting the control rods and servos for the rudder and
elevator installed along with the receiver. I spent a good amount of time dry-fitting
everything in place before gluing - just to make sure there would be no binding and the
like. That's why this step took so long. I started by drilling the holes in part 1-3 for the
control rod sleeves and threading the sleeves into the part and then fitting it into the pod
as far back as I dared. I also trimmed the edges of part 1-3 a bit to get it to fit deep
into the pod (behind the opening under the wing).
</p>
<p>
For the reciever, I ended up using a Hitec Electron 6 after trying a Hitec Superslim 7 and
deciding that I can get the equipment a touch further back in the pod using the Electron.
(Remember I'm concerned about coming out nose heavy. In retrospect, I wonder if using a Berg
5* receiver might have been the way to go since it looks to be smaller than the Electron and
has end connectors which would allow the servos to go back even further.) Since the RX was
going to be tucked well out of reach, I attached servo extensions for the aileron servos and
for the ESC connection to the RX so I would be able to make these connections once
everything was in place.
</p>
<p>
I then focused on the rudder and elevator servos. I taped the HS-55 servos for the rudder
and elevator together side-by-side and then marked the servo rails (parts 1-2) for the screw
holes. I attached the servos to the rails and then plugged them into the RX. At this point,
I started playing with where everything should be located. Once I decided on how far back I
could position the equipment and be free of any binding, I glued the control rod sleeve
holder part in place and glued the servo rails in place.
</p>
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<a href="/articles/liftzone/2003/jun/navaho/pod_with_servos.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/pod_with_servos_t.jpg" width=
"291"></a>
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<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/battery_installed.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/battery_installed_t.jpg" width=
"200"></a>
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The pod with r/e servos and RX in position.<br>
(The RX is tucked well back and is hard to see.)
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Here you see the battery in position.
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<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/all_installed.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/all_installed_t.jpg"
width="200"></a>
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A view under the canopy with battery in place and ESC tucked to the side.<br>
It's tight, but everything fits.
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<p>
<strong>Page 5 (~45 minutes)<br>
</strong> Page 5 is focused on getting the aileron servos and controls in place. The biggest
challenge here was fishing the servo wires through the wing. There's a piece of fishing line
in the wing to help you fish the wires through. However, I was not convinced it would hold
up to the challenge. So, I used the fishing line to fish a thicker string through the wing.
</p>
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<a href="/articles/liftzone/2003/jun/navaho/stout_string.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/stout_string_t.jpg" width="502">
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A stout string in place for fishing the servo wires through the wing.
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</p>
<p>
Then, I dry fittted the servo in the precut hole. This requires sanding/filing down the side
of one of the servo holders so that it can fit in the area at the leading edge of the wing.
Once everything fit nicely, I got ready to fish the servo wire through the wing. The servo
wires on the HS-55 servos are too short, so I added 6" servo extensions to them. To hold the
extensions to the servo wires while being fished through, I added a drop of CA to where the
servo wire and extension connect. Then, it was time to pull the wires through. This was a
challenge requiring a bit of fenagling and twisting to get the wires through. But, they
eventually made it in tact. Once they were through, I put the servo in place and glued the
servo holders in place.
</p>
<p>
This is then followed by installing the aileron control horns and control rods.
Unfortunately while trying to get the proper bends into the aileron control horns, I messed
up. So, I decided to use some control rods with clevises I happened to have. They are pretty
hefty control rods and overkill (and likely contributed to my overweight condition - see
below), but they work. Fortunately, I had not glued the control horns in place yet. So, I
drilled out holes in the horns, and installed the control rods. This did have the
beneficial side-effect of allowing me to attach the control rods to the control horns closer
to the control surface thus giving me more travel in the aileron throws.
</p>
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<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/aileron_servo_inplace.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/aileron_servo_inplace_t.jpg"
width="266"></a>
</td>
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Aileron servo and control rod in place.
</td>
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</td>
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</p>
<p>
<strong>Page 7 (~20 minutes)<br>
</strong> Page 7 has you gluing the canopy hold-down rod to the canopy. Very simple step.
However, I found I had to bend the ends of the rod to allow me to slip the canopy in
place. Also, the rod along with the epoxy popped off one time while installing the canopy. I
reglued it in place and have had no problems since.
</p>
<p>
Page 7 is also where the balancing is done. As anticipated, I was nose heavy. I found adding
about 3/8oz to the tail allowed the plane to balance with the battery pack pushed back as
far as possible. Although my all up weight (AUW) ended up being 22oz (as opposed to the
specified 16-18oz), I wasn't too upset since the wing loading is still less than 10oz/sq.
ft. I also did some informal research among other E-zoners that have the plane, and it
appears that the 16-18oz target is a bit optimistic. So, don't fret if you come out a bit
heavy. Regardless, the plane does not seem to notice the extra few ounces.
</p>
<p>
<strong>Page 8 (~15 minutes)<br>
</strong> Setting the control throws wasn't too troublesome given my Hitec Eclipse computer
radio. However, I was not able to achieve the 20 degrees elevator throw nor, the 35 degrees
rudder throw - even with setting the EPA at 125%. And, since the servo arms were as close as
possible to the fuselage sides already, the only way to eek out any more travel using
mechanical means would be to drill new holes in the control horns closer to the surfaces. I
decided it wasn't worth the trouble. I ended up with about 15 degrees on the elevator throws
and about 25 degrees on the rudder. I figured this would still be sufficient. The aileron
throws were set as per the instructions.
</p>
</blockquote>
<p>
<big><b>Flying</b></big>
</p>
<blockquote>
<p>
So with a little over 4 hours elapsed time into the plane, it was ready to fly. Having
only one other ARF in my fleet, I had forgotten what a time saver it is not to have to apply
covering. If I had to build and cover this plane, it would have easily taken me an
additional 8 or more hours. (I'm very slow.) So, I was quite happy to be ready to fly after
only 4 hours of effort and this includes taking pictures and pondering ad infinitum the
placement of the equipment in the fuselage.
</p>
<p>
For the flight tests, I decided I would first fly the plane using the Mega 16/15/5 and 6x3.5
prop and then change over to the 16/15/7 with the 9x5.
</p>
<p>
<strong>Mega 16/15/5, 8x1100HE battery pack, 6x3.5 Aeronaut Folding Prop<br>
</strong> I had flown this setup on my other sailplane - a Soarwatt - before buying the
7-turn Mega, so I had a feeling for how it would fly and I knew that this setup flew the
Soarwatt pretty much the same as the original sp400 motor I had used. Therefore, I was
confident flying the Navaho using the 5-turn Mega would give a good approximation of what
one could expect with the stock sp400 setup.
</p>
<p>
So, I powered up and gave a light toss into the air. Although it took a bit of straight and
level flight for the plane to get on step, once there, the plane climbed at a good solid
30-45 degree angle. It was a bit windy so at times it would pop up at a higher angle when it
got some wind under its wings. But, the bottom line is that the plane would get to altitude
easily and quickly. I tried some rolls and loops. They were doable from level flight but
were smoother if preceeded with a bit of a dive to get the airspeed up.
</p>
<p>
<strong>Mega 16/15/7, 8x1100HE battery pack, 9x5 Graupner CAM Folding Prop<br>
</strong> Again, having flown this setup on my other sailplane, I had an idea what to
expect. I was not disappointed. In fact, this motor seems to be a better match for the
Navaho than Soarwatt. This setup pulls the plane up at a solid 60+ degree angle and gets it
to altitude very quickly. Additionally, rolls and loops are much more enjoyable. I also flew
some inverted but found it required full down elevator to keep level. If you haven't bought
a power system for the plane yet, then I think this is definitely the way to go.
</p>
<p>
I took some <a href="/articles/liftzone/2003/jun/navaho/launch.mpg">video of a launch</a> with each motor system. It is 5.2MB so be warned.
When watching it, notice how
much quicker the 16/15/7 takes the plane above the treeline in the background. With the
16/15/5 it was necessary to fly level for a bit before climbing. The 16/15/7, on the other
hand, allowed the plane to be yanked back into a steep climb right from the start.
</p>
<p>
<b>Enough of This Motor Talk, What About Gliding?</b>
<br>
I was surprised at how well the plane glided. Although I'm not even close to being
an accomplished thermal hunter/sailplane flyer, and even on a day that I would not say had
alot of lift, I had no problem keeping the plane aloft. With the 7-turn motor, I had two
17-minute flights with 3-4 climbs on two different days. This was followed by a more
thermal-friendly session where I had a 19-minute flight with only 2 climbs and a 20-minute
flight with 2-3 climbs. In all these cases, I still had plenty of juice left in my battery
packs. The main reason for landing was my neck was sore. Furthermore, the 19-minute flight
started with some incredible thermalling where I was able to do Cuban 8s and loops without
the motor on. Very fun. Though, as would be expected with the low AR wing, it doesn't
penetrate in windy conditions as well as some other planes, but I had no problem flying it
in 10mph winds (with some gusts above that). The bottom line here is that this plane soars
quite well.
</p>
<p>
Further evidence of this plane's general desire to stay aloft is that I was having trouble
landing the plane where I wanted to because it would not settle in and drop to the ground.
It just kept on floating along even gaining altitude on final as it would fly over a thermal
or the wind would pick up. As a result, I subsequently dialed in some spoilerons and down
elevator. This helped immensely. Now, once the plane is on final and just about ready to
land, I flip my flight mode switch to pop up the spoilerons (I have them set at about 90%)
and the plane settles right in.
</p>
<p>
<table cellspacing="0" cellpadding="1" width="400" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center" width="50%">
<a href="/articles/liftzone/2003/jun/navaho/flyingpiccloudy.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/flyingpiccloudy_t.jpg" width=
"200"></a>
</td>
<td valign="top" align="center" width="50%">
<a href="/articles/liftzone/2003/jun/navaho/flyingpiclanding.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/flyingpiclanding_t.jpg" width=
"150"></a>
</td>
</tr>
<tr>
<td valign="top" align="center" width="50%">
Flying Into the Wild Gray Yonder
</td>
<td valign="top" align="center" width="50%">
Returning to Terra Firma
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
</blockquote>
<p>
<big><b>Conclusion</b></big>
</p>
<blockquote>
<p>
<b>The Topmodels Navaho has a lot going for it:</b>
<br>
<ul>
<li>
It's well priced.
</li>
<li>
It's a very well made ARF.
</li>
<li>
It's quite transportable given the 1.2m wingspan.
</li>
<li>
And, it flies great.
</li>
</ul>
</p>
<p>
And, if you don't already have the power system picked out or in hand, I would strongly
suggest a setup such as the Mega 16/15/7 so you can swing a nice big prop.
</p>
<p>
<b>Acknowledgements</b>
<br>
I would like to thank fellow E-zoner "Sal C" for taking the in-flight
photos and video.
</p>
</blockquote>
<table cellspacing="0" cellpadding="0" width="400" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="1" cellpadding="5" align="center" border="0">
<tbody>
<tr>
<td valign="top" align="center" width="100%" bgcolor="#E6E6E6" colspan="2">
<p>
<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/intro_plane_pic.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/intro_plane_pic_t.jpg"
width="200"></a></p>
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>Wingspan:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
47" (1210 mm)
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>Wing area:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
338sq. in. (21.8 dm2)
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>Weight:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
Specified: 16-18 oz (450-500 g)<br>
As built: 22 oz (628 g)
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>Wing Loading:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
As built: 9.4 oz/sq. ft (28.8 g/dm2)
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>Motor:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
Mega 16/15/5 and<br>
Mega 16/15/7
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>ESC:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
Jeti 18-3P Gold Label
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>Radio:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
Hitec Electron 6 RX<br>
HS-55 servos
</td>
</tr>
<tr>
<td valign="top" align="right" bgcolor="#E6E6E6">
<strong>Available From:</strong>
</td>
<td valign="top" align="left" bgcolor="#E6E6E6">
Northeast Sailplane Products (<a href=
"http://www.nesail.com/">http://www.nesail.com</a>)
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
<big><b>Introduction</b></big>
</p>
<blockquote>
<p>
I had been flying a sp400 rudder/elevator sailplane for the past year, but I was getting a
bit bored with it. So, I started to look at electric sailplanes with ailerons figuring I
could have a bit more fun in terms of maneuvers and also a bit of fun playing with things
like spoilerons and flaperons. So, when I was given the opportunity to review the TopModels
Navaho from Northeast Sailplane Product (<a href=
"http://www.nesail.com/">http://www.nesail.com</a>), I gladly accepted.
</p>
<p>
The Navaho does not sport a long sleek, high aspect ratio wing like some other sailplanes.
Nor, does it have the latest high-tech airfoil and wing construction. Instead, the
Navaho has a low aspect ratio (6.2), relatively short ,1.2 meter, built-up balsa wing based
on an s4083 airfoil. No, the Navaho is not sexy. Instead, it offers a simple design, with
light wing loading, easy transport, and quick assembly in the field. In other words, it's a
great grab-and-go electric sailplane for hunting lift whenever the opportunity presents
itself.
</p>
</blockquote>
<p>
<big><b>Kit Contents</b></big>
</p>
<blockquote>
<p>
The Navaho is an ARF. It is a relatively quick-building plane with all the hardware
included. Upon opening the box, one sees a fully covered wing and tailfeathers, with a
fiberglass pod and carbon fiber boom. All the covering (which is Oracover) was done very
well and the fiberglass fuselage pod was very well molded with no blemishes.
</p>
<p>
<table cellspacing="0" cellpadding="1" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center">
<a href="/articles/liftzone/2003/jun/navaho/kit_contents.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/kit_contents_t.jpg" width="200">
</a>
</td>
</tr>
<tr>
<td valign="top" align="center">
The kit contents.<br>
It looks like a quick build.
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
Although the parts were all well executed, I was a bit concerned about the instruction
manual. It is presented entirely in pictures/drawings with no text to help the builder along
the process. I like to have a bit of prose to go along with pictures. But, I found that by
going through the manual a few times before sitting down to build helped me assimilate the
instructions. And, hopefully, this review will help add that missing narrative for any other
future Navaho owners.
</p>
<p>
<b>Deviant Behavior</b>
<br>
When doing a review, I don't like to deviate too far from the stock setup and
instructions. However, there were a few obstacles to achieving this goal for the
Navaho.
</p>
<p>
First of all, I no longer have any brushed sp400 gear. So, from the start I knew I would be
using a brushless setup. My previous sailplane had flown on a direct drive sp400 motor
spinning a 6x3.5 prop on 8x1100HE cells, then a Mega 16/15/5 swinging the same prop and
using the same cells, and then finally on a Mega 16/15/7 swinging a 9x5 prop, again on the
same packs. From this experience, I knew that the 16/15/5 was a very close substitue for the
brushed sp400. It basically spun the prop at the same RPMs, but did it at a lower current
draw (i.e. it was more efficient). And, I knew that the 16/15/7 setup was simply fabulous at
pulling the plane to altitude. So, I decided I would fly the Navaho on both the 16/15/5 and
16/15/7 power systems. The former would provide a good example of how the plane would
perform on the stock setup, and the latter would be an example of a more spirited setup.
</p>
<p>
The other problem I had to address was that the instructions show a non-standard (for me at
least) battery configuration using a 7-cell pack. Well, all my packs for this size of plane
are 8-cell packs side-to-side configured. So, based on the configuration and placement of
the pack in the instructions, and based on some posts on the E-zone, I was pretty sure I
would end up with a nose-heavy plane. One approach mentioned on the E-zone to mitigate this
problem was installing the rudder/elevator servos in a tandem configuration near the nose.
This then allows the battery pack to be slid well into the aft end of the fuelseage. Well, I
thought that changing the servo installation was a bit too radical for a product review. So,
I decided to just build the plane pretty much in line with the instructions, and deal with
the nose-heavy condition if necessary. As it turned out I only had to add about 0.5oz to the
tail.
</p>
<p>
Therefore, to summarize, I did deviate from the stock plane in terms of the number of cells
- 8 vs 7, and in terms of the motor - a brushless sp400 size vs. a brushed sp400. However,
the Mega 16/15/5 is such a close replacement for a standard sp400 in terms of power and
RPMs, that I expected the flight tests with this motor would closely match flights with a
brushed sp400 motor. But, I did not deviate in terms of radio installation. I installed the
servos and electronics pretty much as per the instructions (although putting them as far
back in the fuselage as I could) understanding that I would likely have to add weight to the
tail to get the plane to balance.
</p>
</blockquote>
<p>
<b><big>Assembly</big></b>
</p>
<blockquote>
<p>
As I was working on the steps given on page 3 (installing the r/e servos and
receiver), I happened to think about how the wing is held in place and realized that had I
finished page 3 and glued everything in place, I think I would have had a heck of a time
installing the blindnut and plate for the wing bolt. So, I changed the order of the
instructions such that I did Page 6 before Page 3. The rest of the pages were left in their
original order. However, as you will read below, I don't think it would be a bad idea to
even do Page 6 before Page 2 to make rigging the tail feathers and boom easier.
</p>
<p>
<strong>Page 1 (~30 minutes):</strong><strong><br>
</strong> Page 1 is pretty straight forward, but there is a mistake in the instructions
regarding the installation of the elevator control horn. Assuming you installed the rudder
control horn as per the instructions, the instructions for the elevator control horn are
incorrect. Following the instructions would result in the elevator control horn being on the
same side of the plane as the rudder control horn which could cause interference between the
two. Instead, install the elevator control horn on the other side from that shown in the
instructions to avoid this problem.
</p>
<p>
The rest of the instructions on Page 1 are fine and easily followed. However, check the
holes in your control horns before gluing them to the control surfaces. The holes in my
control horns were all too small for the included control rods. It's much easier to ream out
holes before the horns are attached to the surfaces.
</p>
<p>
<table cellspacing="0" cellpadding="1" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center">
<a href="/articles/liftzone/2003/jun/navaho/fin_square.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/fin_square_t.jpg"
width="200"></a>
</td>
</tr>
<tr>
<td valign="top" align="center">
Squaring the fin to the stabilizer while the epoxy sets.
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
<strong>Page 2 (~45 minutes):<br>
</strong> Page 2 is all about gluing the tail to the boom and gluing the boom to the pod.
Attaching the tail feathers to the boom was not too difficult. I used a Dremel to flatten
the top of the boom as per the instructions. And, attaching the tail was a matter of
applying epoxy and then holding the tail and boom together with my hands until the epoxy
set.
</p>
<p>
However, attaching the boom to the pod without any jigs or other aids other than my ability
to line things up was a bit daunting and a rather non-ARF like step. But, I had no choice.
So, I inserted the boom into the pod the appropriate distance (as indicated in the
instructions) and then propped the tail on a couple of rolls of 1" tape. This appears to
give the right vertical angle of boom to pod - I believe. Then, I lined up the horizontal
boom-to-pod angle. Once I was convinced that gluing it like this would be fine, I applied
epoxy and made sure everything was lined up correctly as before and let the epoxy set.
</p>
<p>
<table cellspacing="0" cellpadding="1" width="400" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center" width="100%">
<a href="/articles/liftzone/2003/jun/navaho/tail_propped.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/tail_propped_t.jpg" width="200">
</a>
</td>
</tr>
<tr>
<td valign="top" align="center" width="100%">
Tail propped on rolls of tape in preparation for boom-to-pod attachment.
</td>
<tr>
<td valign="top" align="center" width="100%">
<a href="/articles/liftzone/2003/jun/navaho/straight_boom.jpg"><img
class="c1" height="113" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/straight_boom_t.jpg" width="466">
</a>
</td>
</tr>
<tr>
<td valign="top" align="center" width="100%">
<p>
Side shot of boom and pod attached.<br>
(Red line added to show boom - hidden behind the line - is at the correct angle.)
</p>
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
Unfortunately, I got a little cocky and didn't think I needed to have the wing on the plane
when gluing in the boom. Instead, I figured I could eyeball it using a triangle. I was
wrong. As a result, my tail is a touch off kilter from the wing when looking down the
length of the plane. It's not the end of the world and the plane flies fine, but it is
annoying and I'm mad I wasn't more diligent in this step. So, let this be a warning to you.
In fact, it may even make sense to do Page 6 before Page 2 so that you can officially attach
the wing and set the boom orientation before the epoxy sets.
</p>
<p>
<table cellspacing="0" cellpadding="1" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center">
<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/squaring_tail_feathers.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/squaring_tail_feathers_t.jpg"
width="115"></a>
</td>
</tr>
<tr>
<td valign="top" align="center">
The wrong way to square the tail feathers.<br>
(What was I thinking?)
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
<strong>Page 6 (~30 minutes):<br>
</strong> Regardless, if you didn't do page 6 before Page 2, you will want to do Page 6
now so that you'll have enough working room to put the blindnut and bolt plate in position.
If you do page 3 before page 6, I think you'll find it rather challenging to maneuver these
parts (parts 2-31 and 2-3) in position for gluing. Overall page 6 is not too hard. Attach
the dowel to the wing, and drill the front end of the wing saddle to accept the dowel. Then,
position the wing correctly by measuring the distance between wing tips and horizontal
stablizer tips. Once satisfied with the position of the wing on the pod, drill through the
predrilled wingbolt hole near the trailing edge of the wing and into the pod. Then, assemble
the blindnut and bolt plate and glue it into position.
</p>
<p>
<strong>Page 3 (~20 minutes):<br>
</strong> Now that the wing bolt parts are glued into place in the pod, one can direct their
attention to positioning the equipment that goes in the pod. Page 3 starts that process by
getting the pod ready to accept the motor and by getting the tail boom ready to support the
control rods and sleeves. The steps on page 3 are not difficult. I would suggest, however,
not bothering to actually install the motor at this point since it'll just get in the way in
later steps.
</p>
<p>
<strong>Page 4(~60 minutes):<br>
</strong> The main goal of page 4 is getting the control rods and servos for the rudder and
elevator installed along with the receiver. I spent a good amount of time dry-fitting
everything in place before gluing - just to make sure there would be no binding and the
like. That's why this step took so long. I started by drilling the holes in part 1-3 for the
control rod sleeves and threading the sleeves into the part and then fitting it into the pod
as far back as I dared. I also trimmed the edges of part 1-3 a bit to get it to fit deep
into the pod (behind the opening under the wing).
</p>
<p>
For the reciever, I ended up using a Hitec Electron 6 after trying a Hitec Superslim 7 and
deciding that I can get the equipment a touch further back in the pod using the Electron.
(Remember I'm concerned about coming out nose heavy. In retrospect, I wonder if using a Berg
5* receiver might have been the way to go since it looks to be smaller than the Electron and
has end connectors which would allow the servos to go back even further.) Since the RX was
going to be tucked well out of reach, I attached servo extensions for the aileron servos and
for the ESC connection to the RX so I would be able to make these connections once
everything was in place.
</p>
<p>
I then focused on the rudder and elevator servos. I taped the HS-55 servos for the rudder
and elevator together side-by-side and then marked the servo rails (parts 1-2) for the screw
holes. I attached the servos to the rails and then plugged them into the RX. At this point,
I started playing with where everything should be located. Once I decided on how far back I
could position the equipment and be free of any binding, I glued the control rod sleeve
holder part in place and glued the servo rails in place.
</p>
<p>
<table cellspacing="0" cellpadding="1" width="400" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center" width="50%">
<a href="/articles/liftzone/2003/jun/navaho/pod_with_servos.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/pod_with_servos_t.jpg" width=
"291"></a>
</td>
<td valign="top" align="center" width="50%">
<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/battery_installed.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/battery_installed_t.jpg" width=
"200"></a>
</td>
</tr>
<tr>
<td valign="top" align="center" width="50%">
The pod with r/e servos and RX in position.<br>
(The RX is tucked well back and is hard to see.)
</td>
<td valign="top" align="center" width="50%">
Here you see the battery in position.
</td>
</tr>
<tr>
<td valign="top" align="center" width="100%" colspan="2">
<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/all_installed.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/all_installed_t.jpg"
width="200"></a>
</td>
</tr>
<tr>
<td valign="top" align="center" width="100%" colspan="2">
A view under the canopy with battery in place and ESC tucked to the side.<br>
It's tight, but everything fits.
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
<strong>Page 5 (~45 minutes)<br>
</strong> Page 5 is focused on getting the aileron servos and controls in place. The biggest
challenge here was fishing the servo wires through the wing. There's a piece of fishing line
in the wing to help you fish the wires through. However, I was not convinced it would hold
up to the challenge. So, I used the fishing line to fish a thicker string through the wing.
</p>
<p>
<table cellspacing="0" cellpadding="1" width="400" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center">
<a href="/articles/liftzone/2003/jun/navaho/stout_string.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/stout_string_t.jpg" width="502">
</a>
</td>
</tr>
<tr>
<td valign="top" align="center">
A stout string in place for fishing the servo wires through the wing.
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
Then, I dry fittted the servo in the precut hole. This requires sanding/filing down the side
of one of the servo holders so that it can fit in the area at the leading edge of the wing.
Once everything fit nicely, I got ready to fish the servo wire through the wing. The servo
wires on the HS-55 servos are too short, so I added 6" servo extensions to them. To hold the
extensions to the servo wires while being fished through, I added a drop of CA to where the
servo wire and extension connect. Then, it was time to pull the wires through. This was a
challenge requiring a bit of fenagling and twisting to get the wires through. But, they
eventually made it in tact. Once they were through, I put the servo in place and glued the
servo holders in place.
</p>
<p>
This is then followed by installing the aileron control horns and control rods.
Unfortunately while trying to get the proper bends into the aileron control horns, I messed
up. So, I decided to use some control rods with clevises I happened to have. They are pretty
hefty control rods and overkill (and likely contributed to my overweight condition - see
below), but they work. Fortunately, I had not glued the control horns in place yet. So, I
drilled out holes in the horns, and installed the control rods. This did have the
beneficial side-effect of allowing me to attach the control rods to the control horns closer
to the control surface thus giving me more travel in the aileron throws.
</p>
<p>
<table cellspacing="0" cellpadding="1" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="4" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center">
<a href="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/aileron_servo_inplace.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/aileron_servo_inplace_t.jpg"
width="266"></a>
</td>
</tr>
<tr>
<td valign="top" align="center">
Aileron servo and control rod in place.
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
<p>
<strong>Page 7 (~20 minutes)<br>
</strong> Page 7 has you gluing the canopy hold-down rod to the canopy. Very simple step.
However, I found I had to bend the ends of the rod to allow me to slip the canopy in
place. Also, the rod along with the epoxy popped off one time while installing the canopy. I
reglued it in place and have had no problems since.
</p>
<p>
Page 7 is also where the balancing is done. As anticipated, I was nose heavy. I found adding
about 3/8oz to the tail allowed the plane to balance with the battery pack pushed back as
far as possible. Although my all up weight (AUW) ended up being 22oz (as opposed to the
specified 16-18oz), I wasn't too upset since the wing loading is still less than 10oz/sq.
ft. I also did some informal research among other E-zoners that have the plane, and it
appears that the 16-18oz target is a bit optimistic. So, don't fret if you come out a bit
heavy. Regardless, the plane does not seem to notice the extra few ounces.
</p>
<p>
<strong>Page 8 (~15 minutes)<br>
</strong> Setting the control throws wasn't too troublesome given my Hitec Eclipse computer
radio. However, I was not able to achieve the 20 degrees elevator throw nor, the 35 degrees
rudder throw - even with setting the EPA at 125%. And, since the servo arms were as close as
possible to the fuselage sides already, the only way to eek out any more travel using
mechanical means would be to drill new holes in the control horns closer to the surfaces. I
decided it wasn't worth the trouble. I ended up with about 15 degrees on the elevator throws
and about 25 degrees on the rudder. I figured this would still be sufficient. The aileron
throws were set as per the instructions.
</p>
</blockquote>
<p>
<big><b>Flying</b></big>
</p>
<blockquote>
<p>
So with a little over 4 hours elapsed time into the plane, it was ready to fly. Having
only one other ARF in my fleet, I had forgotten what a time saver it is not to have to apply
covering. If I had to build and cover this plane, it would have easily taken me an
additional 8 or more hours. (I'm very slow.) So, I was quite happy to be ready to fly after
only 4 hours of effort and this includes taking pictures and pondering ad infinitum the
placement of the equipment in the fuselage.
</p>
<p>
For the flight tests, I decided I would first fly the plane using the Mega 16/15/5 and 6x3.5
prop and then change over to the 16/15/7 with the 9x5.
</p>
<p>
<strong>Mega 16/15/5, 8x1100HE battery pack, 6x3.5 Aeronaut Folding Prop<br>
</strong> I had flown this setup on my other sailplane - a Soarwatt - before buying the
7-turn Mega, so I had a feeling for how it would fly and I knew that this setup flew the
Soarwatt pretty much the same as the original sp400 motor I had used. Therefore, I was
confident flying the Navaho using the 5-turn Mega would give a good approximation of what
one could expect with the stock sp400 setup.
</p>
<p>
So, I powered up and gave a light toss into the air. Although it took a bit of straight and
level flight for the plane to get on step, once there, the plane climbed at a good solid
30-45 degree angle. It was a bit windy so at times it would pop up at a higher angle when it
got some wind under its wings. But, the bottom line is that the plane would get to altitude
easily and quickly. I tried some rolls and loops. They were doable from level flight but
were smoother if preceeded with a bit of a dive to get the airspeed up.
</p>
<p>
<strong>Mega 16/15/7, 8x1100HE battery pack, 9x5 Graupner CAM Folding Prop<br>
</strong> Again, having flown this setup on my other sailplane, I had an idea what to
expect. I was not disappointed. In fact, this motor seems to be a better match for the
Navaho than Soarwatt. This setup pulls the plane up at a solid 60+ degree angle and gets it
to altitude very quickly. Additionally, rolls and loops are much more enjoyable. I also flew
some inverted but found it required full down elevator to keep level. If you haven't bought
a power system for the plane yet, then I think this is definitely the way to go.
</p>
<p>
I took some <a href="/articles/liftzone/2003/jun/navaho/launch.mpg">video of a launch</a> with each motor system. It is 5.2MB so be warned.
When watching it, notice how
much quicker the 16/15/7 takes the plane above the treeline in the background. With the
16/15/5 it was necessary to fly level for a bit before climbing. The 16/15/7, on the other
hand, allowed the plane to be yanked back into a steep climb right from the start.
</p>
<p>
<b>Enough of This Motor Talk, What About Gliding?</b>
<br>
I was surprised at how well the plane glided. Although I'm not even close to being
an accomplished thermal hunter/sailplane flyer, and even on a day that I would not say had
alot of lift, I had no problem keeping the plane aloft. With the 7-turn motor, I had two
17-minute flights with 3-4 climbs on two different days. This was followed by a more
thermal-friendly session where I had a 19-minute flight with only 2 climbs and a 20-minute
flight with 2-3 climbs. In all these cases, I still had plenty of juice left in my battery
packs. The main reason for landing was my neck was sore. Furthermore, the 19-minute flight
started with some incredible thermalling where I was able to do Cuban 8s and loops without
the motor on. Very fun. Though, as would be expected with the low AR wing, it doesn't
penetrate in windy conditions as well as some other planes, but I had no problem flying it
in 10mph winds (with some gusts above that). The bottom line here is that this plane soars
quite well.
</p>
<p>
Further evidence of this plane's general desire to stay aloft is that I was having trouble
landing the plane where I wanted to because it would not settle in and drop to the ground.
It just kept on floating along even gaining altitude on final as it would fly over a thermal
or the wind would pick up. As a result, I subsequently dialed in some spoilerons and down
elevator. This helped immensely. Now, once the plane is on final and just about ready to
land, I flip my flight mode switch to pop up the spoilerons (I have them set at about 90%)
and the plane settles right in.
</p>
<p>
<table cellspacing="0" cellpadding="1" width="400" align="center" bgcolor="#000000" border=
"0">
<tbody>
<tr>
<td>
<table cellspacing="10" cellpadding="0" align="center" bgcolor="#E6E6E6" border="0">
<tbody>
<tr>
<td valign="top" align="center" width="50%">
<a href="/articles/liftzone/2003/jun/navaho/flyingpiccloudy.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/flyingpiccloudy_t.jpg" width=
"200"></a>
</td>
<td valign="top" align="center" width="50%">
<a href="/articles/liftzone/2003/jun/navaho/flyingpiclanding.jpg"><img
height="150" src="http://static.rcgroups.com/articles/liftzone/2003/jun/navaho/flyingpiclanding_t.jpg" width=
"150"></a>
</td>
</tr>
<tr>
<td valign="top" align="center" width="50%">
Flying Into the Wild Gray Yonder
</td>
<td valign="top" align="center" width="50%">
Returning to Terra Firma
</td>
</tr>
</tbody>
</table>
</td>
</tr>
</tbody>
</table>
</p>
</blockquote>
<p>
<big><b>Conclusion</b></big>
</p>
<blockquote>
<p>
<b>The Topmodels Navaho has a lot going for it:</b>
<br>
<ul>
<li>
It's well priced.
</li>
<li>
It's a very well made ARF.
</li>
<li>
It's quite transportable given the 1.2m wingspan.
</li>
<li>
And, it flies great.
</li>
</ul>
</p>
<p>
And, if you don't already have the power system picked out or in hand, I would strongly
suggest a setup such as the Mega 16/15/7 so you can swing a nice big prop.
</p>
<p>
<b>Acknowledgements</b>
<br>
I would like to thank fellow E-zoner "Sal C" for taking the in-flight
photos and video.
</p>
</blockquote>