THE IDEA going flying field spare glow plugs plug batteries fuel fuel pump muffler etc return ing home clean planeno exhaust messis certainly appealing No starting problem just flip switch away go manufacturers commended efforts bring electric age After reading about seeing available electric power hard ware decided try itbut slightly different design approach electric models now market could believe classified sport Sunday flier types essentially powered gliders rudder-only types necessitated weight motor power supply limited power available Astro flights Astro-25 looked promising us powerplant relatively hot model aerobatic capable model flat bottom wing floater wanted able pattern maneuvers model would have config ured aerobatic capability long will Astro 25 run What prop should use motor de signed 9 X 7 prop turning 9000 rpm 15-minute chargeit will run eight minutes use 10-in prop attempt gain power advises manufacturer will overheat motor burn up armature brushes result short flight duration fun model designed 19 powered Whiplash published Nov 74 AAM looked basis electric model overall size creased somewhat get reasonably light wing loading airfoil changed semi-symmetrical would give us better lift capability still aerobatic full 4-channel installation planned Basic aerobatic designtapered wing strip ailerons generous rudder area etcwere used insure good performance Noth ing revolutionary just sound basic propor tions Fuselage size kept minimum presented biggest prob lem due size weight neces sary battery packs Astro-25 motor unusual arrangement servo installation behind wing accessible through hatch enabled us achieve normal balance point aircraft wing built-up rather foameored lightest possible weight Using vertical spar webs gave necessary strength Plywood fuselage doublers believed necessary because battery weight inherent result light structure heavy powerplant setup somewhat fragile model penalty has ac cepted get aerobatic performance Anyway dont plan crash prototype model built Greg Mali nowski genial proprietor local hobby shop Monmouth Hobby Center Greg went out lightness selecting best balsa keeping glue minimum Builder prototype Greg Malinowski poses Electric trans parent Solar Film covering shows off light-weight construction techniques Greg went far make cut-outs wing ribs tail surfaces went Out selecting light balsa keeping use glue minimum Throttle servo linked small switch on-off control used equipment its smallest servos EHLEUHRIC ONDE careful attention weight successful Pattern job can built using Astro-25 get-up-and-go cutting lightening holes wing ribs tail surfaces etc Solar Film used cover model transparent type show off structure Greg used Pro-Line radio smallest servos throttle servo linked small switch on-off motor control proof flyingand first flights showed us far aerobatic electric model seen heard about Essentially Class B maneuvers can accomplishedconsec utive loops rolls stall turns spins Cuban eights can done also showed us propeller selection critical tremendous effect performance flight duration Flying also must planned split-s turns dives before maneuvers help Much climbing harder power supply plane quite easy fly must careful committed error trying goaround landing approach batteries running out Pushing throttle lever forward didnt help Like plane stalls falls quite easy build Try select light wood sand thoroughly use glue sparingly make real effort keep light payoff will increased aero batic capability fly carefully Dont crashcontinued page 24 Above Close-up nose shows clean installation Astro 25 motor Cooling air enters directly motor exits Out fuselage bottom Rev-Up 9 x 7-1/2 prop found good performer Right Power supply motor takes lot space Wedged cooling air can go through battery packs On-off switch firewall control cable throttle servo Safety shorting plug fuselage side permits motor run plug Electric Some notes construction would suggest cutting out parts ahead time basically make own kit will save time overall cut ribs out individually never did like stack-and-sand method Leaving building feet ribs shown makes building alignment easy lower spar can pinned work board ribs added top spar trailing edge lead ing edge spar webs leading trailing edge top planking added much building done before removing wing board likely warp before bottom planking added No dihedral brace necessary fibreglass cloth/epoxy adequate Ply wood tip plates quick easy may help aerodynamically will protect scrapes bad landings Tail surfaces simply sheet balsa use lightening holes see fit fuselage critical part Plywood doublers attached con tact cement forward bulkheads epoxy nose section must strong contain heavy battery packs Triangle stock along fuselage edges adds strength allows rounding appear ance motor retained tight fit its rolled plywood mounting tube sure allow cooling air passages batteries motor cooling air exists fuselage bottom dont let air go onto batteries An air scoop fuselage top gets air battery com partment exits bottom below batteries prototype second scoop wings upper surface hole through wing leading edge center section feel necessary radio equipment unusually placed behind wing trailing edge accessible top fuselage hatch location necessary obtain proper balance point Room inside crowded aileron servo should mounted wing deep possible maybe laid its side clearance small switch linked throttle servo off-on control As safety feature Greg incorporated shorting plug mounted fuselage side such motor could run place easy forget electric motor will runany radio throt tle advanced serious accident could result have Electric mod est step evolution electric powered r/c aircraft Future advances motor battery technology hopefully result ing better power-to-weight ratios will give us design flexibility days may step line Class C Expert pattern competition flip switch watch electric powered model climb silently air its aerobatic performance Above Weight battery packs calls unusual radio equipment location accessible through hatchalso balances model Below motor installed removed tight friction fit rolled thin plywood tube epoxied fuselage Wire connectors plug Onto rear motor
Edition: Model Aviation - 1975/08
Page Numbers: 23, 24
Edition: Model Aviation - 1975/08
Page Numbers: 23, 24
THE IDEA going flying field spare glow plugs plug batteries fuel fuel pump muffler etc return ing home clean planeno exhaust messis certainly appealing No starting problem just flip switch away go manufacturers commended efforts bring electric age After reading about seeing available electric power hard ware decided try itbut slightly different design approach electric models now market could believe classified sport Sunday flier types essentially powered gliders rudder-only types necessitated weight motor power supply limited power available Astro flights Astro-25 looked promising us powerplant relatively hot model aerobatic capable model flat bottom wing floater wanted able pattern maneuvers model would have config ured aerobatic capability long will Astro 25 run What prop should use motor de signed 9 X 7 prop turning 9000 rpm 15-minute chargeit will run eight minutes use 10-in prop attempt gain power advises manufacturer will overheat motor burn up armature brushes result short flight duration fun model designed 19 powered Whiplash published Nov 74 AAM looked basis electric model overall size creased somewhat get reasonably light wing loading airfoil changed semi-symmetrical would give us better lift capability still aerobatic full 4-channel installation planned Basic aerobatic designtapered wing strip ailerons generous rudder area etcwere used insure good performance Noth ing revolutionary just sound basic propor tions Fuselage size kept minimum presented biggest prob lem due size weight neces sary battery packs Astro-25 motor unusual arrangement servo installation behind wing accessible through hatch enabled us achieve normal balance point aircraft wing built-up rather foameored lightest possible weight Using vertical spar webs gave necessary strength Plywood fuselage doublers believed necessary because battery weight inherent result light structure heavy powerplant setup somewhat fragile model penalty has ac cepted get aerobatic performance Anyway dont plan crash prototype model built Greg Mali nowski genial proprietor local hobby shop Monmouth Hobby Center Greg went out lightness selecting best balsa keeping glue minimum Builder prototype Greg Malinowski poses Electric trans parent Solar Film covering shows off light-weight construction techniques Greg went far make cut-outs wing ribs tail surfaces went Out selecting light balsa keeping use glue minimum Throttle servo linked small switch on-off control used equipment its smallest servos EHLEUHRIC ONDE careful attention weight successful Pattern job can built using Astro-25 get-up-and-go cutting lightening holes wing ribs tail surfaces etc Solar Film used cover model transparent type show off structure Greg used Pro-Line radio smallest servos throttle servo linked small switch on-off motor control proof flyingand first flights showed us far aerobatic electric model seen heard about Essentially Class B maneuvers can accomplishedconsec utive loops rolls stall turns spins Cuban eights can done also showed us propeller selection critical tremendous effect performance flight duration Flying also must planned split-s turns dives before maneuvers help Much climbing harder power supply plane quite easy fly must careful committed error trying goaround landing approach batteries running out Pushing throttle lever forward didnt help Like plane stalls falls quite easy build Try select light wood sand thoroughly use glue sparingly make real effort keep light payoff will increased aero batic capability fly carefully Dont crashcontinued page 24 Above Close-up nose shows clean installation Astro 25 motor Cooling air enters directly motor exits Out fuselage bottom Rev-Up 9 x 7-1/2 prop found good performer Right Power supply motor takes lot space Wedged cooling air can go through battery packs On-off switch firewall control cable throttle servo Safety shorting plug fuselage side permits motor run plug Electric Some notes construction would suggest cutting out parts ahead time basically make own kit will save time overall cut ribs out individually never did like stack-and-sand method Leaving building feet ribs shown makes building alignment easy lower spar can pinned work board ribs added top spar trailing edge lead ing edge spar webs leading trailing edge top planking added much building done before removing wing board likely warp before bottom planking added No dihedral brace necessary fibreglass cloth/epoxy adequate Ply wood tip plates quick easy may help aerodynamically will protect scrapes bad landings Tail surfaces simply sheet balsa use lightening holes see fit fuselage critical part Plywood doublers attached con tact cement forward bulkheads epoxy nose section must strong contain heavy battery packs Triangle stock along fuselage edges adds strength allows rounding appear ance motor retained tight fit its rolled plywood mounting tube sure allow cooling air passages batteries motor cooling air exists fuselage bottom dont let air go onto batteries An air scoop fuselage top gets air battery com partment exits bottom below batteries prototype second scoop wings upper surface hole through wing leading edge center section feel necessary radio equipment unusually placed behind wing trailing edge accessible top fuselage hatch location necessary obtain proper balance point Room inside crowded aileron servo should mounted wing deep possible maybe laid its side clearance small switch linked throttle servo off-on control As safety feature Greg incorporated shorting plug mounted fuselage side such motor could run place easy forget electric motor will runany radio throt tle advanced serious accident could result have Electric mod est step evolution electric powered r/c aircraft Future advances motor battery technology hopefully result ing better power-to-weight ratios will give us design flexibility days may step line Class C Expert pattern competition flip switch watch electric powered model climb silently air its aerobatic performance Above Weight battery packs calls unusual radio equipment location accessible through hatchalso balances model Below motor installed removed tight friction fit rolled thin plywood tube epoxied fuselage Wire connectors plug Onto rear motor
