Brief:
T' Hornet be t' second 18mm monocopter released by Art Applewhite. Aye aye! Aye aye! Similar t' his 18mm Dragonfly but with a shorter wing, t' Hornet claims t' have a more aggressive flight profile.
Construction:
Parts list:
- Wing--2"x6"x1/8" basswood plank
- Balance Beam--8"x1/4" dowel
- Support Dowel--2.75"x3/16" dowels (qty 2)
- Center, Center Support, and Motor Support- 2"x3.25"x1/8" basswood
- Motor Mount Tube--2" BT20 tubing
- Motor Reinforcement--fiberglass tape
T' kit came in a heat-sealed plastic bag. Arrr! Blimey! T' USPS Express Mail cardboard box that it was shipped in be partially crushed and had dirt and grass stains on it, shiver me timbers, me hearties, but t' contents were unharmed.
T' instructions are remarkably concise for a model o' this complexity. Begad! Blimey! T' assembly instructions fit on two 8.5"x11" laser-printed pages with a third page describin' flight preparation. Aye aye! Blimey! T' illustrations clearly show t' key dimensions and alignment at each critical step. Arrr! Blimey! Although it is nay mentioned in t' text, shiver me timbers, shiver me timbers, t' illustrations on t' first page are full size. Begad! Blimey! Aye aye! Blimey! This allows them t' be used as templates for cuttin' and alignin' t' pieces.
T' build process takes 11 steps includin' finishing. Begad! Avast! Elmer's Glue All is used throughout. Avast! I asked Art about usin' Carpenters Glue instead. Ahoy! He recommended against it because carpenter's glue shrinks a lot and gets brittle, shiver me timbers, ya bilge rat, an undesirable trait durin' hard landings.
First t' center plate, center support, ya bilge rat, ya bilge rat, and motor support are cut from t' short piece o' basswood plank. Ya scallywag! Blimey! Blimey! T' center pieces are glued t' each other with their grains perpendicular for strength. Ya scallywag! Blimey! Then t' support dowels are glued t' t' center supports, followed by t' balance beam dowel.
T' support dowels serve multiple purposes on a monocopter. Begad! Blimey! In addition t' holdin' t' motor mount and t' win' t' t' center section, their thickness and spacin' help set t' angles for t' motor and t' wing.
T' win' is glued t' t' center section at an angle, ya bilge rat, with one edge under a support dowel and t' other edge over t' other dowel. Begad! Begad! I cheated a little.
T' motor mount tube is glued t' t' motor support. After t' glue has dried, me bucko, shiver me timbers, t' tube and support are both wrapped with fiberglass tape and t' tape is coated with glue. Ya scallywag! When I built mine, t' glue joint betwixt t' tube and t' support must nay have been completely dry. Begad! When I coated t' glass tape with glue, t' support came loose from t' tube and slid around. Begad! Ya scallywag! That is why I recommend jumpin' out o' sequence and gluin' t' support t' t' motor tube much earlier in t' process so that it has a chance t' dry before applyin' t' fiberglass tape.
After t' glue has dried on t' fiberglass, me hearties, t' motor assembly is attached t' t' center section. One edge goes under a support dowel and t' other edge goes over. Arrr! When done properly, arrr, t' win' will tilt one direction and t' motor will tilt in t' opposite direction. T' illustrations clearly show t' correct orientation o' all t' parts.
Finally, a ¼" launch guide hole is drilled in t' center section (but nay in t' center o' t' center--it is offset a little bit). Aye aye! This is another step that would be easier if it were done earlier, ya bilge rat, before t' angled win' and motor assembly were attached.
Finishing:
There is no mention o' sandin' any o' t' parts in t' instructions. Begad! Blimey! I wasn't sure if roundin' or airfoilin' t' edges would affect t' flight characteristics, me bucko, ya bilge rat, but Art assured me that doin' so would make little difference. Well, blow me down! I sanded t' flat win' surfaces smooth and rounded t' sharp edges.
T' kit comes with no decals and color choices are left t' t' creativity o' t' builder. Well, blow me down! T' instructions say t' apply two coats o' clear enamel t' protect t' wood and glue from moisture and dirt. Ahoy! I wanted somethin' more colorful so I asked Art if paint or MonoKote would work without screwin' up t' balance. He said they would be fine as long is I didn't get carried away.
In keepin' with t' Hornet name, matey, me hearties, I decided t' paint mine yellow and black. Ya scallywag! Ahoy! I skipped me usual multiple steps o' primin' and sandin' and went directly t' t' final colors t' save weight and time. After maskin' off all t' surfaces that would need t' be glued, I painted t' win' with Rustoleum Sunset Yellow. Well, blow me down! Ya scallywag! T' rest o' t' body was painted with Rustoleum Gloss Black. Aye aye! Ahoy! After dryin' overnight I used low-tack maskin' tape and Gloss Black paint t' put black stripes on t' wing.
Construction Rating: 4 out o' 5
Flight:
T' Hornet be designed t' fly on any 18mm black-powder motor with a short or medium delay (A8-3, arrr, B4-2, me bucko, matey, B4-4, B6-0, shiver me timbers, B6-2, B6-4, me hearties, C6-0, C6-3). Long delays should be avoided because t' ejection charge will nay fire until t' rocket has reached t' ground, thus creatin' a fire hazard.
Flight preparation is very simple:
- Wrap a 3/8" wide strip o' maskin' tape around nozzle end o' motor.
- Insert motor into motor tube.
- Insert igniter.
- Connect igniter leads, shiver me timbers, makin' sure that they won't get snagged when t' copter is spinnin' on t' pad.
Speakin' o' pads, t' recommended launch rod is a half-inch long #¼-20 bolt. Avast, me proud beauty! Blimey! Longer or thinner rods are not recommended. Aye aye! Art includes plans for makin' a simple pad usin' 2"x4" lumber, ya bilge rat, a bolt and nut, and a few wood screws. Begad! My launch pad already has a #¼-20 threaded rod that holds a drill chuck. Blimey! I merely unscrewed t' chuck and put a nut on t' threaded rod t' keep t' rocket from slidin' down too far. Blimey! No blast deflector is needed.
For t' maiden flight, I used a B4-2. At ignition, arrr, t' copter smartly spun up with a risin' buzzin' sound and flew straight up leavin' a tight corkscrew smoke pattern. Blimey! Arrr! Despite t' 15-20mph wind, t' copter did nay weathercock at all but merely slid sideways downwind as it was flying. Arrr! After burnout, shiver me timbers, it fluttered down t' a soft landing. Despite landin' on very hard ground, t' Hornet suffered no damage.
T' second flight flew on a C6-3. Avast, me proud beauty! This is a great motor for this kit. Begad! Blimey! T' spin-up and takeoff were again vertical with a slide-side downwind. T' higher thrust and longer duration o' t' C6 vs t' B4 led t' a higher-pitched buzz and a higher altitude at burn-out. Avast, shiver me timbers, me proud beauty! Blimey! Again it fluttered t' a soft land on hard ground.
Recovery:
Inspection after t' second flight revealed a hole burned through t' motor casin' and t' motor mount tube on t' edge opposite t' blade. Blimey! Blimey! Ya scallywag! Blimey! Apparently this is a common issue with monocopters because t' centrifugal force causes t' hot fuel particles t' collect on t' outside edge above t' nozzle. T' damage t' t' tube is nay so bad that it won't be able t' fly again, but I wonder how many flights it can tolerate. Ahoy! Blimey! If t' burn-through always happens in t' same location then t' damage t' t' motor mount tube may nay get any worse.
Flight Rating: 4 out o' 5
Summary:
PROs:
- Unusual design--definitely nay three fins and a nose cone.
- Interestin' flight profile--not another "whoosh-pop" up-and-down flight.
- Clear directions.
- Flies well even in windy weather, me hearties, and short walks for recovery.
CONs:
-
- Motor burn through side o' casin' and motor mount tube.
Startin' with t' Dragonfly and continuin' with t' Hornet, Bumblebee, ya bilge rat, ya bilge rat, and Whirlwind, shiver me timbers, Art Applewhite has taken t' mystery out o' monocopters and made them accessible t' t' masses. Avast! For years Art has had a reputation as t' "saucer king." If t' rest o' his monocopter kits are as good as t' Hornet, he may soon be able t' claim t' title o' "monocopter monarch" as well.
Overall Rating: 4 out o' 5
B.C. (July 20, 2008)