35 Sand flapsanddrillfor flap horn (noteoffset— seeplan).Installflaps
and hingetemporarilyto wing
36Mountthreeservos Makeallpushrodsasshownon planHingerudder
and elevatorCheck allcontrolsforfreemovement
37.Removeengine,R/Cgear,landinggear mainstrutsandallcontrolsurfaces
This modelmaybe covered withSuperMonoKote(followinstructionson
enclosed leafletclosely)or alternativelymaybe covered andfinishedusing
silkanddope Hingeallcontrolsurfacespermanentlyafter covering
38. Installfueltankreceiver,battery,wheels,engineandspinner,andcockpit
canopy Check CG (see planforcorrect position) and ifnecessarymove equip-
mentfore or afttoget CG correct
FLYING
With a good 35 to 45-size enginetheairspeed isa relativelyconstant 70
to 80mphAutomaticspeed controlis anadvantageduringmaneuveringThis
isachieved by propellerselection,airfoil,andflyingweightof under6 lbs
The planformof theplan,wingshape withswept leadingedge and fuselage
profileprovideexcellentyawstabilityandaccurateroll response
The stuntflaps,whichwillbe describedlater,contributeexcellent lateral
stability
Anearlysymmetrical planeandneutralstabilitycoupled with efficient
or
large control surfacesproduce the Noblers maneuverabilityThe rudderand
elevator areunusuallylargefora modelairplaneThe aileronsarereflexing
trailingedge sectionswithsealedhingegap givingrapidaccuratelinearresponse
with littledragNormalcontrolsurfacemovementsare ailerons± 10degrees,
elevator ± 15degrees,and rudder± 30 degrees The coupledflaps move ±
5degrees
For manyyearscontrollineplanes have had mechanically coupled flaps
and elevators to givethemsmootherflightandmore liftinsharpcorners The
same advantagesapplywithRC planesControllinemodels used equalcoupled
flapandelevatormovement,whiletheRC modelsshouldhavemuch
less
flap
movementthanelevatormovementThis is becauseof theinferiorpower/weight
ratioof RC modelscomparedto CL models,and theconsequentnecessityto hold
down thedragto maintainflyingspeed
Aradiocontroledmodelgainsotheradvantages withflaps Forexample,
withmore pitchaxispower,we canhave a moreforwardCG locationforgroovier
flyingWhendeflecteddownward,thecentersectionof thewingis operatingat
ahigherangleof attackthanthewingtipsensuringagainsttipstallingduring
highg maneuversor low speeds Withtheadditionalliftof theflapstheplane
needs less rotationabout its pitchaxis fora given response, therebycausing
less dragspeed changes,andshowinga smootherflightpathThe symmetrical
airfoil is,therefore,infinitelyvariableto obtainoptimumperformance
When landing or takingoff,the flapsallow slower and more stable flight.
Even ingustyor windyweather,the Nobler seems to flyas if on railsThe
flaps keep thewingsextrastablebecause thewingtips areflyingat a lower
angleof attackwhiletheotherfeatureskeepittrackingaccuratelyEventhough
the flapsarenotsharplydeflected,theyprovidea tremendousamountof additional
lift, even at low speeds
The techniqueof usingflapscoupled withthe elevator functionisrelatively
new to RC flyingA detailedinvestigationof theperformancewiththeflaps
and withouttheflapshasbeenmadeAt the1969 DCRC Symposium,Fred Marks
and EdSweeney presented a paperdescribingthe techniqueshowingthe results
of
testsand experiments with several airplanes
To
make their findingsmeaningful,
7