Distributed exclusively by Great Planes Model Distributors P.O. Box 9021 Champaign, IL 61826-9021 Phone: (800) 338-4639 www.electrifly.com
Yak-55, which was already a winner of several World Aerobatic
Championships, went through a series of structural changes in 1989
resulting in the Yak-55M. The end result was an airframe with an
increased taper on the wing but reduced wingspan and area that allowed
for higher roll rates. When I first saw the
Yak-55M being announced by ElectriFly, I was very excited and could not
wait for the day where I could get my hands on this great rendition of
the legendary aerobatic champion.
First of all, the Yak-55M is
not advertised as a 3D airframe. It is meant to be a precise acrobatic
airframe that gives you the feeling of flying a much larger airframe in
a more manageable 50.5" wingspan. It can be powered by the RimFire .32 and
a 4S2200mAh batteries which should be common in any electric fliers
battery box. With it's great looks and promise of performance, I cant
wait to get started on this Yak55M and see what she has to offer. So
lets dig in...
Magnetic canopy with latching mechanism for added safety
Two-piece wing for quick field assembly
Air foiled horizontal and vertical stabilizers
Fiberglass cowl with which attaches with powerful magnets
Genuine TopFlite MonoKote covering
Yak-55M arrived in a colorful and well packaged box which contained
individually wrapped components all taped down to survive the rigors of
shipping. Once all the items were removed and laid out on my workbench,
I had to check the box again to see if I was missing something as there
are very few components required to complete the Yak-55M. Initial
inspections showed no damage to any of the components and the covering
looked good with no major issues.
of the first things that strikes your eye with the Yak-55M ARF is the
magnetically attached cowl which employs four strong magnets to hold
the cowl in place. The magnets are attached to an inner ring, which mates to the magnets on the firewall, making a
very clean installation. In addition to the cowl, there is a plastic
grill and spinner included. Although the real Yak-55M does not have a
spinner, I think the white spinner looks great on this model.
wings and stabilizers were flawless. The ailerons come pre-hinged
from the factory but the elevator and the rudder have to be hinged by
the modeler. I was actually very excited to see the beautiful airfoil
on both stabilizers. This Yak-55M should fly very precisely with these
canopy is held in by two carbon fiber rods on the front and a powerful
magnet on the back. Additionally, the canopy has a little wooden
mechanism that allows it to lock in place. The way to remove the canopy
is to push it towards the nose
and de-latch it first then lift it off. I almost broke the canopy the
first time I tried to remove it as I was not aware of this latch.
canopy also comes with a very detailed dash sticker and a plastic
canopy floor that is left off to allow the modeler to install a 1/5th
landing gear is aluminum with fiberglass spats, which in my opinion is
the only thing that should be put on the end of a Yaks landing gear.
The tail gear is the type that is inserted in the rudder to provide the
steering mechanism. It should work nicely with a model that is so light.
the items that were supplied for the review include the 4S2200mAh
battery, the 45A Silver Series ESC, the RimFire .32 motor and 4 S3150
servos. I've used all of these items before and know from personal
experience that they all work very nicely together and expect to have
zero issues with them in this build as well.
manual contains clearly documented steps to aid in bringing the Yak-55M
together. Detailed instructions are given for each step of the assembly
process and the recommended CG and control surfaces directions are
started the build of the Yak-55M with the tail section so that I
could get all of the
required gluing out of the way. The horizontal stabilizer inserts in
the opening of the rear of the fuselage and is epoxied in place. The
stabilizer was perfectly parallel with relation to the wing right out
of the box and I did not
have to mess with any adjustments which made me pretty happy. The two
elevator halves are connected together with a pre-bent metal rod that
has to be installed as the stab is being glued in. I placed a little
oil around the metal to make sure that epoxy would not stick to the
metal and that it would have a full range of movement afterwards. The
elevator halves can then be CA hinged, and the metal connector epoxied,
to the stabilizer.
both elevator halves hinged, the rudder can be installed by first
installing the tail gear and then the CA hinges. The whole tail section
comes together very quickly and looks great once it is done. One thing
you will realize here is that the rudder throw is limited by the
elevator on both sides. If this was a 3D airframe, it could pose a
little problem but as I discovered while flying the Yak, the amount of
rudder throw is more than enough for precision flight allowing for some
very nice knife edge passes.
main gear also comes together very quickly as there is no drilling or
tapping required. Once the axles are bolted in place, the spats simply
install with two screws and bolts through pre-drilled locations. No
messing up the angle of the spat here. The wheels are held in place
with four wheel collars. The whole assembly slides into the side of
the fuselage through pre-cut slot and then bolts in place using six metal
screws. I first had a problem installing one of the screws as the
washer was making contact with the fuselage till I discovered that in
the parts kit was a supplied washer that was half cut which I assume
was specifically put there for this location. A bonus indeed.
is essentially the bulk of the build. The rest of the build involves
installing the radio and power system and getting the Yak-55M ready for
Futaba S3150s are installed in the wings by removing some covering and
drilling and hardening the locations for the screws. You will need
two 9 - 12" servo extenders for this step.
specifically instructs you to not install the plastic grommets on the
servos but instead use a simple wood screw and washer to hold the
servos in place which makes for a perfectly flush installation. The
control horns are then simply screwed in place into the hard wood
locations on the ailerons. You
can harden the wood here with some thin CA to make sure that they wont
ever back out again.
push rod connection is made by placing a bend in the rod and routing it
through the servo horn. They are locked in place with a plastic retainer. The
supplied rods fit perfectly through the long arms of the S3150s with
7C sits squarely in the middle ground in computer systems. It's a
system that offers much of the 9C's set-up versatility matched to
4-channel ease of use. Like all other computer systems on this page, it
offers Dial 'n Key? simplicity for programming, and the 2.4GHz FASST
system for an unparalleled RF link.
Dial 'n Key programming
Large 72 x 32 LCD screen with adjustable contrast
6-character model naming
Digital trims, trim memory, EPA, sub-trims and servo reversing (all channels)
the elevator and rudder servos are housed in the tail section. The same
method used to install the aileron servos is employed for the tail
servos by cutting, drilling, tapping/hardening the wood and installing
the servo with a screw and a washer. The control horns are then
installed into the hardened wood sections of both the elevator and the
rudder. I really like the fact that there is only one servo for the
elevator making it a light, no fuss installation.
linkages for the rudder and elevator are the same as the ailerons. I
was pleased to see that the finished assembly was completely slop free.
At this point, I also installed the R617FS receiver by using some double sided
tape and small piece of hook-loop tape to attach it to the vertical
member right below the wing tube.
RimFire .32 which was supplied for this review mates perfectly to the
holes that have been pre-drilled and prepared with blind nuts on the
firewall. All that is left for the modeler to do is to attach the
X-brace to the motor and attach it using four screws.
Silver Series 45A ESC can then be taped/strapped to the side of the
motor box and the leads routed inside the fuselage through the air
holes. I used a piece of double sided tape again to first stick the ESC
in place, then I wrapped the whole assembly including the slack of the
wires with a piece of hook-loop tape.
recommended 4S2200mAh battery straps nicely in the fuselage. There is
ample space to move the battery forward and aft to make fine adjustments in
CG. Note the aluminum thumb screws that are used to hold the
wings in place. I really like these screws as they are very easy to
attach and remove without any tools and they are very light.
as Ammo motors have revolutionized brushless inrunner technology,
RimFire motors have done the same for outrunners! The combination of
superior performance and a competitive price makes these power plants a
great value. Plus, the wide selection means there's a RimFire motor
that's ideal for whatever the application, including
brushed-to-brushless upgrades as well as glow-to-electric conversions.
Equip your airplane with a RimFire, and watch it reach new heights!
Engineered for explosive acceleration and maximum torque.
The lightened aluminum motor can houses high-torque, "rare-earth" Neodymium magnets.
Better cooling means 50% more power than many others outrunners of similar size.
Dependable and virtually maintenance-free; no comms or brushes to worry about, and bearings are double-shielded.
include hardware, gold-plated bullet connectors (male connectors are
installed; female connectors are included) and a motor mount.
Silver Series brushless ESCs, the only way their performance would be
any easier to enjoy is if they came already installed. As it is,
hook-up takes only seconds ? and set-up takes no time at all. Silver
Series brushless ESCs do it automatically on hook-up, and offer the
option to use brake (or not) with a flick of the throttle stick. And
with seven affordable models to choose from, there's a Silver Series
ESC for almost any airplane and brushless motor combination.
Compatible with LiPo, NiCd and NiMH batteries for maximum versatility.
Ready to use, with leads and Deans®Ultra Plug®Connector, gold-plated bullet plugs for motor and universal radio connectors already attached.
No set-up. Detects starting voltage at hook-up ? and sets the low-voltage cutoff automatically!
smooth, precise and responsive throughout the throttle range.
Transition from instant full-power thrust to all-power off in the same
heartbeat and enjoy longer flights and cooler operation in the long
deliver true rated current and the extra amps that digital servos ? or
extra-servo setups ? require. (Except SS-45D & SS-60)
Brake/No Brake operation. Stop folding props cold ? or let fixed props freewheel.
Protect pilot, plane and ESC with Safe Start programming, and automatic heat and current overload features.
preparing the canopy of the Yak-55M, I decided to install the optional
1/5th scale pilot figure. The provided canopy floor is prepared by
attaching the dash sticker and the pilot can be glued on with some
medium CA. The whole assembly can then be installed and glued in place
from the bottom of the canopy. The completed canopy really looks
great with the 1/5th pilot figure.
mentioned before, the cowl is attached to the fuselage using magnets
attached to an inner wooden ring. Do a test fit first to make sure that
all four magnets are making contact. I noticed I had to move a portion
of the inner ring a little close to the edge of the cowl to make a
perfect fit. Since it is attached with CA, it is relatively easy to
break the original bond, move it a little and then fix it in place with
some thin CA. The engine grill can then be cut and glued to the
cowling. Make sure you place the spinner backplate on the motor to
determine how much of the grill you need to cut. I used a rotary
grinder to get as close to a perfect circle as possible after making the
everything in place, the final bit of assembly is to mount the 12x6E
propeller to the motor and attach the spinner. With the battery placed
midway in the fuselage, the Yak-55M balanced very close to the
recommended CG. The completed Yak55 looks fantastic and I cant
wait to get her in the air.
maiden flight of the Yak-55M happened to land on a nice but windy day for Houston. The Yak-55M fits
nicely in the back of my SUV so I do not have to take the wings off for
transportation. However field assembly would be very
easy as the supplied aluminum wing bolts are very easy to work with and
you only need to make two servo connections to get the Yak-55M ready to
at the field, I strapped in the 4S2200mAh battery in the center position and rolled the Yak-55M
around the runway a little bit to observe its ground handling
capabilities. The Yak-55M is very responsive on the ground and can be
taxied without fear of tipping over. With all of the pre-flight checks
done, I lined the Yak-55M on the top of the runway and started to apply
throttle. Within a few feet, the tail lifted off and she was airborne.
Coming out of the first turn, I had to apply a few clicks of right and
down trim to get her to fly level. Once that was done, I started to
realize how nicely the Yak-55M cuts through the air. The recommended S3150 servos do a great job
of controlling the surfaces and what you end up with is a very precise
airframe that stays where you put it and flies straight and true no
matter what the orientation is.
taking it easy for five minutes or so on the first battery and doing
some simple loops, rolls and stall turns, I decided to land and check
how much was left in the battery. I lined the Yak-55M with the runway
and reduced the throttle and allowed it to gently glide in for a
very soft landing on the mains. Very nice, I thought to myself. After
checking the battery, I noticed that I had used approximately ~%65 of
the battery so I decided to set my timer to 6 minutes overall.
subsequent flights, I started to really enjoy what the Yak-55M was
capable of. Quick rolls are very axial, point rolls can be performed
very precisely and slow rolls only require small inputs from rudder and
elevator to keep the fuselage tracking straight throughout the maneuver. I found my self
constantly over correcting as I tried to perform precise maneuvers and
realized that the Yak-55M only needs the slightest touch. Even against a
fairly strong 10-15mph wind, the Yak-55M flew very straight and precise
and did not get thrown around like a smaller electric would. Knife edge
flight had very little coupling towards the canopy which I easily mixed
out and it was a true pleasure to fly the Yak-55M on its side all across
the runway with nothing but the rudder.
though there is a reference to 3D rates in the manual, the Yak-55M is
not a 3D airframe. I was however able to end up performing some very
nice rolling harriers which especially looked good coming out of fast
rolling circles. The limited throw on the rudder and the speed of the
S3150 servos limit the amount of hoverbatics that Yak-55M can perform
but again, that is not what this airframe was designed for. The Yak-55M
also allows you to perform some very nice avalanches.
day, we also had our friend Robert show up who is one of the better
IMAC pilots that I know. I handed him control of the Yak-55M and let him
take her up for three flights. It was a pleasure to watch Robert fly
the Yak-55M as it was meant to be flown, fast and precise. Robert also
commented on how precise the airframe allowed him to perform vertical
climbs and rolls. Robert also performed some of the best
looking flat turns I've seen being flown on a small electric while
alternating from upright to inverted which unfortunately did not make it in the video.
There is no doubt in my mind that this Yak-55M will be my one of my favorite airplanes going forward.
Check out the video to
see her in action!
Yak-55M (Pilots: Burc Simsek, Robert Bryant - Stills & Video: Burc Simsek and David Smith)
Download the Video (30.2MB) CLICK HERE
every new airframe that comes to market these days claiming that it is 3D
capable, it is nice to see an airframe that is specifically designed
for precision. As advertised, the Yak-55M flies like a larger airplane,
and with a 50.5" wingspan, is not really that small in reality. It is very precise and goes
where you point it.
its durability, in one of my flights, I was not paying attention
to the timer and hit the LVC. I was too far out to make it back safely
to the runway so I decided to land it in the uncut grass. When the main
gears hit, the Yak-55M came to an immediate halt and toppled over. I was
pleased to see that there was no damage at all to the airframe from
this minor incident. Of course this is not to say that the Yak-55M would
survive undamaged from a more forceful impact after all it is a very
light balsa airframe and not meant to be crash landed. But from what I
have seen so far, it is one of my sturdier airframes.
I am very pleased with both the looks and the performance of the
Yak-55M. I think the optional pilot figure is a must for this airframe
as it really pushes the scale looks over the top. The color scheme that
was chosen is very visible on both sides, and the airframe can do any
aerobatic maneuver you can throw at it. Having such a
surgical instrument that is easy to transport, setup and fly will certainly push me to expand my
piloting skills in the precision department.
Great job ElectriFly!
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The comments, observations and conclusions made in this review are solely with respect to the particular item the editor reviewed and may not apply generally to similar products by the manufacturer. We cannot be responsible for any manufacturer defects in workmanship or other deficiencies in products like the one featured in the review.