Stevens Aero Model SQuiRT User manual

1
© 2005 Stevens AeroModel all rights reserved.
SQuiRT
Aileron Wing Kit
V1.02b
Span 38” / Area 260Sq.”

2
© 2005 Stevens AeroModel all rights reserved.
WARRANTY
Stevens AeroModel guarantees this kit to be free from defects in both material and workmanship
at the date of purchase. This warranty does not cover any component parts damaged by use or
modification. In no case shall Stevens AeroModel’s liability exceed the original cost of the
purchased kit. Further, Stevens AeroModel reserves the right to change or modify this warranty
without notice.
In that Stevens AeroModel has no control over the final assembly or material used for final
assembly, no liability shall be assumed nor accepted for any damage resulting from the use by
the user of the final user-assembled product. By the act of using the user–assembled product,
the user accepts all resulting liability.
If the buyer is not prepared to accept the liability associated with the use of this product, the buyer
is advised to return this kit immediately in new and unused condition to the place of purchase.

3
© 2005 Stevens AeroModel all rights reserved.
REQUIRED TO COMPLETE KIT:
Kit Contents:
1. Rolled Computer Drawn Plan Sheet
2. Illustrated Instruction Manual
3. Laser Cut Balsa and Hardwood Parts Sheets (See Cut Parts Inventory Sheet)
4. Included Hardware
5. 2 - 1/8” x 17.5” Hardwood dowels
•1-1/8”x3”hardwooddowels.
• 1 - 6” length of servo guide tube (paper)
•1-#16RubberBands(10).
•2-.045”x5”PushRods.
• 1 - Pair Balsa Aileron Stock.
• 1 - Pair Fiberglass Control Horns.
•1-Du-bro845E-ZConnectors(2/Pkg.)
Recommended Finishing Items:
1. One roll of AeroFILM covering available from www.stevensaero.com
Suggested Electronics:
1. 4 Channel Transmitter.
2. 2 - Hitec HS-55 Servos (use of HS-55 servos will negate the need for two 6” servo extensions)
3. 2 - 6” Servo Extension (Only required if you do not use the suggested HS-55 Servos)
4. 1 - 6” Servo “Y” Harness
Items You May Need:
1. Thin CA (super glue) or White Glue
2. Plan/Table Protector (use the bag that this kit came in to protect your work surface from CA glue spills)
3. Razor Blade(s)
4. Med-Fine Grit Sand Paper and sanding block
5. Clear Tape
6. Balsa Wood Filler

5
© 2005 Stevens AeroModel all rights reserved.
INSTRUCTIONS:
Thank you, for purchasing this Stevens Aeromodel SQuiRT – Aileron Wing Kit. This kit provides the builder and pilot a
refreshing change of pace from heavy “ARF” style plywood box airframe construction and blends stick and tissue design
methods of the past with state of the art CAD technology and precision interlocking laser cut parts; the result is something
you will find truly exceptional to build and fly. This kit is intended for a beginner-novice builder and beginner pilot as a
primary 3-channel trainer.
Best Regards,
Bill Stevens
[email protected]
Stevens AeroModel “Laser Engineered Kits™”
P.O. Box 15347
Colorado Springs, CO 80935

6
© 2005 Stevens AeroModel all rights reserved.
Wing Assembly
Basic assembly method. Friction fit all parts together prior to gluing. Sanding parts prior to assembly is not advised
nor should it be required. Prior to installing tab/notch parts gently pinch the tab of each part to allow it to slip into the
corresponding notch. Do not try and force parts together – instead use a solid work surface to support your work
and gently install parts using a rocking motion. You’ll find, particularly when installing the D-Lock ™ interlocking d-
tube sheeting, that slightly rubbing back and forth over the tab notch joint with your finger tip will help seat your parts.
Please use thin CA glue for the entire assembly. Do not use thin CA glue without a glue tip installed as you’ll be in
for a sticky mess. Use the poly tube that this kit was shipped in to protect your plan sheet or work table from CA
spills (Cut tube down one side and unfold over your plans – CA glue will not stick to this poly tube). We suggest that,
as you assemble this wing, you only tack glue the parts at the tab/notch locations. Once the assembly has been
completed you should thoroughly wick thin CA glue into all joints. Note that one small drop of CA glue will
adequately wick into a surface joint of about 2 inches in length! CA Accelerator (Kicker) is a handy item for setting
your glue joints faster and will become a necessity should you need to repair parts/joints where the bonding surface
is already soaked with old/set CA glue.
Hint: Keep from gluing yourself to the work! – wrap each finger tip with masking tape. This will prevent you from
bonding yourself to the wing during assembly!
 Join S1a to S1b to create S1 main spar.
 Join part W5 to bottom center of S1 spar. Next, interlock parts W1 to spar S1 on either side of W5 take note of
the part orientation as W1 is etched to correspond with the R1 rib location. Secure assembly with CA glue at
the tab and notch locations. (see plan sheet for more detail)

7
© 2005 Stevens AeroModel all rights reserved.
InstallRibsR2towingassemblyinthe locations indicated on the plan sheet.
Nextlayinthe1/16”plyspardoublerS2betweenribsR2andontheaftsideofsparS1–retaintheplydoubler
by slipping ribs R1 over the spar and doubler. Wick thin CA in between the balsa S1 spar, ply doubler S2, and
ribs R1.
 Install Ribs R3 as indicated on the plan sheet. Next, Install Rib R4 at wing tips as indicated on the plan sheet.

8
© 2005 Stevens AeroModel all rights reserved.
 Install Rib R2a as indicated on plan sheet.
 Install parts TE2 at wing center section trailing edge as indicated on the plan sheet (etched arrows up). Next,
join parts TE1 to either side of TE2 (the arrows etched on the surface of TE1 should face those of TE2).
Finalize center section trailing edge by installing the 1/16” ply doubler TE3 along trailing edge of wing center
section using the recess created by parts TE1 and TE2 to position the part.

9
© 2005 Stevens AeroModel all rights reserved.
 Complete the trailing edge by first assembling parts TE4 and TE5. Notice that TE5 is etched with “FRONT” this
surface should face up when you install TE4. Also note that TE4 is keyed to fit in only one direction. Install the
completed assembly to the wing trailing edge spanning ribs R2, R2a, R3, and R4. Again, please note the part
orientation as the etch marks on TE5 should face the front or leading edge of the wing. You’ll see where this
orientation is important as the tip of each trailing edge part is tapered up at an angle to match the wing tips.
 Using a new sharp razor blade, cut the provided 6” paper tube into two equal 3” lengths. Gently sand the burr
(from cutting) off each end of these tubes. Next install these between R1 and R2 by gently working the part into
R1 from the bottom side of the wing until it clears R2 and can then be centered between the ribs. Hint: Use a
twisting motion and gentle pressure to work the tube into position. DO NOT GLUE THIS TUBE IN YET

10
© 2005 Stevens AeroModel all rights reserved.
 Install ply servo pocket SR1 to wing assembly between ribs R2 and R2a. SR1 is notched to only fit in one
direction. Once satisfied with the fit, glue both parts SR1 and the paper servo guide tube (installed in the
previous step).
 Install lower cap strips W9 (bottom of R2) and W9a (bottom of R2a and ribs R3).
 Install part SR2 over ply servo pocket SR1.

11
© 2005 Stevens AeroModel all rights reserved.
 Reinforce trailing edge at rib R2. First, install part R2b to double aft section of R2a as indicated on the plan
sheet. Finally, on the opposite side of R2 install triangular part TE1a.
 Sheet center wing section starting with W6. Double check that W6 is centered between R1 prior to committing
the part with glue. Next, complete the center section by installing W7 and W8 as indicated on the plan sheet.

12
© 2005 Stevens AeroModel all rights reserved.
 Install the D-Loc™ sheeting part W2 to complete the D-Tube assembly. Align with tabs on top of spar and tack
glue each tab and notch. Next run glue along the underside of the sheeting at the backside of the spar. Allow
part to completely dry. Place flat on your work surface and gently wrap W2 sheeting down to interlock with the
notches in each rib. You can set these tab/notch joints by gently rubbing your finger over the top of each notch
allowing the tab to firmly seat into position. Work your way down the wing from the root securing the W2 D-
Loc™ sheeting with CA glue at each interlock point. Complete assembly by slightly pinching D-Tube together
at the leading edge of each rib, then wicking in Thin CA, along the inside edges – allow glue to set prior to
moving to the next rib bay.
 Install upper spar caps W10 (atop rib R2) and W10a (atop rib R2a and ribs R3). First glue the caps to the
notches in W2 and allow glue to set. Next, individually wrap each spar cap down to interlock with trailing edge
and glue. Complete by running thin CA glue along underside of spar caps where they meet the tops of each rib.
 Install W3 wing tip as indicated on plan sheet and aligning bottom edge of W3 with bottom edge of R4. Cap
wing tip with part W4 using the same method used for installing spar caps.

13
© 2005 Stevens AeroModel all rights reserved.
 Complete the wing assembly by installing the 2” length of 1/8” hardwood dowel spanning the wing center
section leading edge and 17.5” length of 1/8” dowel across the remainder of the leading edge (cut/sand off
excess dowel that extends beyond wing tip).
Sandthewingtipsround.
 Sand the trailing edge cap strips and the center section wing sheeting to taper into the trailing edge. Mind what
you are sanding and don’t take too much material off the trailing edge; simply bring the cap strip and sheeting to
the trailing edge thickness. The photos below illustrate the required sanding.

14
© 2005 Stevens AeroModel all rights reserved.
 Notice that the rib cap strips forward of the ailerons are inset into the trailing edge stock. Use a sanding block,
lightly blend the trailing edge of the remainder of the wing to match the height and angle of the of the spar cap
strips. Simply center the block over each rib bay and lightly stroke up and down to work the material to the
proper height and angle. See the illustration below for more detail.
 The only real preparation you will need to make to the pre shaped aileron is as follows: Use a sharp knife to
remove any fibers still retaining the lightening hole pieces. Punch out the lightening holes lightly sand the top,
bottom, and inside edge of aileron. Notice that you have a Right and Left aileron – also notice that the ailerons
will hinge from the top (meaning the taper to allow for travel should face the bottom of the wing) and that one
end of the aileron has been laser cut to roughly the proper angle to match your wing tip. Using masking tape,
temporarily attach the right and left aileron to the wing in their respective positions allowing for 1/32” gap
between the inside edge of the wing at R2 and aileron stock. With the aileron taped into position sand a slight
bevel (as illustrated) to the outside edge of the aileron stock following the taper of the wing tip. Finally, sand
along the wing tip edge to match the aileron stock to the wing tip.

15
© 2005 Stevens AeroModel all rights reserved.
 Optional, Finish off the wing by filling any imperfections or gaps with balsa wood filler or a lightweight spackling
compound then loading a fine grit (400) sand paper on your sanding block and lightly sand smooth the entire
wing. Fill the small seam between the leading edge dowel and wing and the seam at the wing tips, allow to dry,
sand wing to remove excess filler. Remember, your covering job is only as good as your surface preparation!
Covering the model
 A complete guide to covering using AeroFILM and AeroFILM Lite is available for download from
www.stevensaero.com Download this document and use it as a guide for covering the SQuiRT. No surprises
here just follow the directions and work slowly remember any imperfections will need to be sanded smooth as
the covering will expose every bump or drip of CA glue.
 A template has been provided on the plan sheet for cutting out a wind screen decal. We typically cut this from
black adhesive backed AeroTRIM or AeroFILM.
Final Assembly
 For a detailed final assembly guide for the SQuiRT please visit www.stevensaero.com. Remove a small piece
of covering from the center section of the wing assembly to allow access for the servo wires to pass through the
wing.
 Temporarily mask the ailerons from the underside of the wing leaving a 1/32” gap between the leading edge of
the aileron and the trailing edge of the wing. Hinge the top side of the ailerons to the wing assembly using clear
scotch tape. Remove the masking tape, flex the aileron up and double with another length of tape along the
underside of the aileron/wing hinge point.
 Slot the covering in the ailerons over the laser cut control horn pocket. Install the fiberglass control horns to the
aileron and secure with a few well placed drops of Thin CA glue.
 Refer to the plan sheet for the servo horn positioning. Remove the servo horn from the servo; connect to your
radio with the trim tab centered to re-center the servo. Next, re-install your servo horns rotated away from the
aileron hinge point at a 45 degree angle (as detailed on the plan sheet). The angle of the servo horn relative to
the hinge point of the aileron and position of the aileron control horn introduces differential aileron travel. In
other words with the suggested linkage setup you will notice that your ailerons travel further upward then down.
This works to counter adverse yaw due to the extra drag created from the downward traveling aileron. This
differential aileron travel will allow you to make reasonably clean turns without necessitating coordinated rudder
inputs. We suggest you read “The Pilots Guide To Mastering Radio Control Flight” by Scott Stoops (available
from www.stevensaero.com) for a more detailed discussion of adverse yaw. Install your servos (HS-55’s) and
connect the aileron linkage to the servos using the supplied Du-Bro 121 EZ-Links. Refer to the plan sheet as a
guide.
Attachthewingtothefuselageusingnomorethenfour #16 rubber bands. For the best crash resistance, do
not cross your rubber bands. Also remember more rubber bands increases the tension on the wing and will
make it more likely to break in a crash. Use fresh rubber bands after a week’s flying.
Testyourradiosetupforfunction and proceed on to first flight.

16
© 2005 Stevens AeroModel all rights reserved.
First Flight
 Are you using fresh rubber bands for each attachment? If not, then replace the motor mount, landing gear, and
wing rubber bands with new.
ThebalancepointorCG(CenterofGravity)isthesame as that listed for the 3ch SQuiRT – please see your
plan sheet for more detail. You roughly would like the model to balance ¼” forward of the wing spar.
 Sight along wings and tail surfaced and remove warps if found. Your rudder should be perpendicular to your
horizontal stabilizer and your horizontal stabilizer should be parallel to your wings. Wing tips should not twist
down in the back (wash in). Ailerons should be evenly set and matched with trailing edge of wing.
A simple way to check your wing for warps is to sight along the underside of the wing from the back of
the model – to do this let your models main gear rest on the ground stand behind the model and raise
the tail up until you can see the underside of the wing. Slowly drop the tail until the underside of the
wing starts to vanish from your line of sight – hold the model in this position and compare the visible
surfaces of the top and bottom of both wings. If you can see more of the bottom of the right wing
compared to the left then you probably have a bit of wash-out (a slight twist up at the wing tip trailing
edge) in the right wing alternatively you may have a bit of wash-in in the left wing or the tendency for
the wing trailing edge to twist down. You can also lay each wing half on a flat surface, hold the root of
the wing (inside rib) flat against your table top and observe if your wing lies flat on the table. Wash
out will make the plane more stable and spin resistant, as the tips of the wing will continue to fly while
the root is stalled. Wash-in will make the plane more difficult to fly at near stall speeds. A model that
always drops one wing at stall will often have a bit of twist in the wing or wash-in on the wing that
drops.
Setcontrolsurfacethrows.
Suggested Control Surface Travel
Elevator +/- 1/2 "
Rudder +/- 3/4"
Aileron + 1/2” – 3/8”
Chooseacalmdayandagrassyfieldforyourmaidentrimflight!
 Slowly advance throttle to ¾power – pick a point on the ground about 100’ out and give the SQuiRT an easy
LEVEL toss into the wind aiming at that point on the ground DO NOT THROW THE PLANE UP into the air.
Alternatively you may ROG (rise off ground) by setting the SQuiRT on a smooth dirt or paved surface facing into
the wind and advancing the throttle slowly - steer with rudder to track the plane straight – within about 10-20’
you will be airborne. Either way allow the plane to climb slowly under power resisting the urge to add excessive
elevator to climb out. Climb out to 100+ feet and begin trimming the plane for level flight at cruise.
 First trim the SQuiRT in pitch. You will notice that the SQuiRT will climb under power this is part of the planes
nature and stems from it’s positive stability (the SQuiRT will recover rapidly to level flight from a dive by simply
centering the control surfaces and allowing the plane to fly itself out of trouble). To trim for pitch set your throttle
to just over ½. Next, use the trim tab on your transmitter for elevator to add or decrease elevator trim until you
have the plane flying level. Reducing power or adding power will necessitate re-trimming the plane in pitch.
Remember when you want your plane to climb add power not up elevator. When you want to descend, reduce
power.
 Next, trim the plane in roll. Using the aileron trim tab on your transmitter add left or right aileron trim until the
wings are level.
Next,trimtherudder.Withthepoweroffenterashallowdiveandnoteiftheplanetracksrightorleft.Trimthe
plane to track straight in a shallow dive.
 The SQuiRT carries energy very well and will glide in nicely for simple landings once the plane has been
trimmed.
Enjoyyour4chSQuiRT!

17
© 2005 Stevens AeroModel all rights reserved.
SQuiRT Flight Guide
Aileron Supplement
Written By Scott Stoops
“The Pilot’s Guide to Mastering Radio Control Flight”
www.rcpilotguide.com
About the Author
A lifetime in aviation would be an accurate description of the involvement Scott Stoops has had in both the RC modeling
world and full-scale aviation. He grew up in an aviation family, with his father being an airline pilot. From an early age, he
exhibited an interest in all things aviation. With the help of his father, he built his first RC model aircraft at the age of 10.
He stayed active in RC models for the balance of his adolescence, which was only limited by his education and interest in
full-scale aviation.
At the age of 16, he soloed a full-scale aircraft and progressed quickly through his FAA licenses, becoming a
commercially rated pilot and Certified Flight Instructor at the age of 18. He specialized in tailwheel, instrument, and
aerobatic instruction. While working full time as a flight instructor, glider tow-pilot, and cargo pilot, Scott completed his
college degree. Upon completing college at 21 years of age, with over 2800 hours of flying experience, he was hired by
United Airlines as a Boeing 737 First Officer. Since that time he has flown as a First Officer on the Boeing 737-200, 737-
300, Airbus A320, Boeing 767/757, and as a Captain on the Boeing 737-300.
While learning to fly and working as an instructor, Scott’s interest in aerobatic flight grew. He learned and later taught
aerobatics in a variety of aircraft. He has also competed in a Russian Yak-55 in full scale International Aerobatic Club
contests progressing through the ranks towards the Advanced category. Scott currently flies the Russian Sukhoi Su-26mx
in the Advanced category. He currently has over 10,000 hours of full scale flying including over 1500 hours of tailwheel
and aerobatic experience.
At home, Scott and his wife Michelle have three lovely children Andrew (7), Alex (5), and Abigail (2). It is his interest in
passing along the joy of model aviation to his family and friends that has sparked and renewed his involvement in model
aviation in recent years. He currently enjoys building, testing, and reviewing models for a major magazine and model
manufacturer. As well, he has written a book titled “Mastering Radio Controlled Flight” from which the following excerpts
have been taken. The book encompasses all aspects of RC flight training including basic flight training, precision
aerobatics, and 3D flight. For more, visit his site at www.rcpilotguide.com.

18
© 2005 Stevens AeroModel all rights reserved.
This guide is offered as an addendum to the original Squirt Flight Guide and is intended to smooth out your transition to
the new aileron wing for your Squirt. Good luck and have fun!
Transition to Ailerons
The primary difference between flying a R/E/T equipped model and an aileron-equipped model is not that one has
ailerons for roll control and one doesn’t, but rather that the aileron-equipped model has, inherently, less overall roll
stability. This is primarily due to the lack of dihedral on the aileron-equipped model. This will provide a small challenge
when transitioning to an aileron-equipped model, as the model will have significantly less self-righting tendencies. You’ll
be forced to make corrections in roll that would have normally been self-correcting in your R/E/T trainer. To me, the
transition to an A/E/R/T model is not a significant one. Where it becomes challenging is when a pilot makes the transition
to a fast model (think a P-51 or Spitfire) or one with a high wing loading (think heavy weight with a small wing) as their
first aileron model. The transition to an aileron-equipped model is challenging enough without adding the additional speed
and agility of a high performance aileron model to the learning process. A more acceptable transition would be from an
R/E/T trainer, to an A/E/R/T aileron trainer, then on to a Warbird or other faster aileron model. Your decision to purchase
an aileron wing for your Squirt is a good one!
From a “flying the plane” point of view, ailerons present several changes to your maneuvering. With ailerons, we’ve split
roll control from yaw control. The ailerons control the roll of the airplane, while the rudder controls the yaw. Turns, as a
result of the decreased dihedral, are a full four-channel exercise. Coordinated turns now require additional control inputs
on the rudder as well as the ailerons to counter adverse yaw.
Adverse Yaw
There are two different kinds of drag that are important to understand, Parasite and Induced. Parasite drag occurs as a
result of pulling objects like the landing gear, antenna, and control linkages through the air and is directly related to the
speed of the aircraft. The faster the airspeed, the higher the parasite drag. The second drag, induced drag, is a by-
product of creating lift. Anytime we create additional lift, we create additional induced drag.
Adverse yaw is a direct result of induced drag. For this example, we’ll initiate a roll into a left turn. When we initiate the
left turn, the left aileron deflects above the wing and the right aileron deflects below the wing. For all practical purposes,
we decrease the lift on the left wing allowing it to drop, and increase the lift on the right wing causing it to be raised. As a
result of increasing the lift on the right wing, the drag is increased on the right side of the airframe. The by-product of that
increase in drag on the right wing is a yaw to the right (opposite the direction of roll). To counter adverse yaw, simply
apply rudder in the direction of the turn...i.e., left turn - left aileron - left rudder. A coordinated turn is one that has been
corrected for adverse yaw. A little later on we’ll discuss some exercises to improve your turn coordination.

19
© 2005 Stevens AeroModel all rights reserved.
Aerodynamics of Turning Flight
It’s just a turn, right? I mean, add a little rudder or aileron and away she
goes, right? Well, sort of. While it is true that most models will turn with
only a touch of aileron/rudder, there are techniques that allow a smooth
transition into and out of bank angles and ensure that the model is
coordinated in roll and yaw during the turn. In fact, during a constant
altitude, constant speed turn, all of the controls are used (including the
throttle).
So what exactly is a coordinated turn? A coordinated turn is one that
maintains a constant rate of turn with zero sideslip. In other words, the tail
follows the nose. It is not uncommon for pilots to slip through an entire
turn. Slipping through a turn causes a large increase in the drag during the
turn. In many ways it can be compared to a car skidding around a turn. In
fact, we use similar terminology to describe uncoordinated turns with
aircraft that is used to describe a poorly cornering car. When the nose is
tracking behind the actual rate of turn, it is called slipping. Conversely,
when the nose is tracking ahead of the rate of turn of the aircraft, it is
called skidding.
It is not only uncomfortable for the occupants (not a particularly large
concern in our models) but is also just sloppy flying.
Note** The term “coordinated turn” is one that describes a turn made by
an aileron equipped model. If you fly a Rudder/Elevator/Throttle (R/E/T)
equipped model, the built in dihedral of the wings handles the coordinating
of the turn for you, but this is still good reading as you will be flying an
aileron model before long**
Note** I know many relatively experienced pilots that have never used
these techniques for turning flight, and their models fly fine. It is true that
some aileron models do not exhibit adverse yaw during turning flight (and
as such do not require rudder coordination). I do find, however, that the
vast majority of aileron trainers require rudder inputs for coordinated flight.
That said, your model will turn with just aileron inputs, it just may not
be perfectly coordinated. In time, I hope that you will integrate this skill into
your flying**
Our goal is to make a constant altitude, constant speed, and constant rate
turn. This will require the use of all four controls. To initiate the turn, add a
small amount of aileron to establish a roll rate towards the intended bank
angle. Most planes, as a result of adverse yaw from the ailerons, will yaw
slightly in the opposite direction of the roll. To keep the turn coordinated in
yaw, add a small amount of pro turn rudder (left aileron/left rudder). This
will cause the nose to fall in line with the turn radius rather than fall to the
outside of the turn (slipping).
As for the other flight controls involved with turning, they are the elevator
and the throttle. The elevator will be used to raise the nose slightly during
the turn to maintain altitude. Why is this necessary? During a turn we use
a portion of the lift created by the wings to change the flight vector of the
aircraft (changing heading) through a bank angle. With a decreased
amount of lift being used to maintain altitude, it is necessary to increase
the lift of the wing to avoid descending. The only way to do this at a
constant speed is to increase the angle of attack of the wing. We do this
through an up elevator input. Keep in mind that this elevator input only
lasts as long as the turn and will cause a balloon in altitude if you don't
take it out as you roll out of the turn.
The last control is the throttle. In a turn, we use the throttle to maintain a
constant airspeed. As mentioned above, total airframe drag is increased
during a level turn. You may need to add a touch of throttle to overcome
the additional drag during the turn.
Who ever thought a simple turn could be so complicated? Fortunately
after a little practice, you'll find yourself making the necessary adjustments
without thinking about it

20
© 2005 Stevens AeroModel all rights reserved.
Dutch Rolls
Dutch rolls are a maneuver that I use to teach better roll and yaw coordination. The primary goal of Dutch rolls is to learn
the correct amount of rudder to add in the direction of a roll to keep the nose coordinated as the aircraft enters a turn. I
recommend practicing this maneuver flying away from yourself initially. Start by rolling slowly into a 30-degree left bank.
Uncorrected, the nose will yaw slightly to the right. Add just enough left rudder to keep the nose from displacing away
from center. Once you reach a 30-degree bank angle, roll into a 30-degree bank to the right, and add enough right rudder
to keep the nose from yawing to the left. Notice how much right rudder it takes to counter the adverse yaw caused by
rolling into that right bank. Repeat until you are comfortable with the correct amount of rudder required to coordinate the
turn.
After mastering the maneuver flying away from your self, try it flying towards yourself. It will be frustrating at first, but just
remember that you are adding rudder in the direction of the aileron input. Hopefully this maneuver will help to get your
fingers trained to compensate for adverse yaw and keep those turns coordinated.
Slips
Slips are a maneuver that we’ll use to help prepare you for crosswind takeoff and landings. In the most basic sense,
slipping flight is uncoordinated flight. Anytime the model is flown with a sideslip condition (i.e., not going where the nose
is pointed), it is slipping. While it‘s a poor technique to use during turns (discussed earlier), slips can be a very useful
technique during crosswind takeoffs and landings. The second common use of slips is to increase the rate of descent by
increasing the drag on the airplane.
With an aileron-equipped model, it is possible to yaw the aircraft one direction, and roll the aircraft in the opposite
direction, causing any turning tendencies to be nullified (i.e. the model continues flying straight ahead). Used in this
manner, the aircraft will be flying sideways through the air and is known as a forward slip (as the aircraft continues
heading “forward”). This significantly increases the drag on the model and thus increases the rate of descent. This is
helpful when you are above your intended flight path and need to increase drag to get back on path.
To practice forward slips and compare their effectiveness in increasing drag, we must compare the rate of descent
between an idle descent rate and an idle “slipping” descent rate.
To start, set up a descent with the throttle closed and mentally record how fast the model descends. Then, after climbing
back up to altitude, set up another idle descent. Once established, roll into a 15-20 degree bank in one direction. Add
enough opposite rudder (i.e. right aileron/left rudder) to stop any turning tendencies and fly straight ahead. Notice the
increased rate of descent. To recover, simply neutralize your cross control inputs and the model will fly normally.
Practice with several different bank angles, adjusting the rudder to maintain a slip with no heading change.
The more common use of a slip is in crosswind takeoffs and landings. This will be explained in the next section but suffice
to say that even Jet Transport Aircraft use slips when taking off and landing in crosswinds. Basically, by de-linking the
rudder with the aileron in a slip we can control bank and yaw independently, allowing precise heading and drift control.