Brief:
This is a plastic model conversion (PMC) I did o' t' Revell 1/48 scale F-16C for t' "Advanced" NARTREK program. Well, blow me down! Ya scallywag! Blimey! It be fast and easy t' do. Arrr! Well, blow me down! Blimey! It is also a great first PMC t' try because t' kit comes already painted in USAF "Thunderbirds" colors. Because o' this, arrr, it has less emotional investment in t' event o' "plastic death", matey, as some call this part o' our hobby. It flies extremely well on C6-3 power if (and only if) balanced properly and built straight. T' Revell kit is rated for ages 10 and above and I think kids about that age could accomplish and fly this conversion with minimal adult supervision. Avast! However, in general, PMC is definitely nay for beginners.
Construction:
There are 3 really essential components t' successful PMC o' model aircraft kits:
- You cannot add too much nose weight.
- Wings, stabs, motor tube, me bucko, and launch lug must all be 0-0-0-0 degrees incidence t' each other or you risk lawn-dart under power results.
- You must keep engine heat away from t' low-temperature plastic or t' 1st flight will be t' last due t' meltin' damage.
Many plastic model kits are nay suited t' PMC for t' simple reason that t' largest rocket motor that can be crammed inside will nay lift it safely with all t' added nose ballast needed for balance. T' Revell 1/48 F16C is perfect for PMC t' 18mm Estes power because a BT-20 motor tube slides neatly inside with only minimal surgery t' t' hull. Begad! Better yet, ya bilge rat, t' natural restin' place for t' motor tube is magically zero-zero degrees thrust line t' t' flyin' surfaces with no fussin' or shimmin' or custom cut, me hearties, matey, odd-shaped centerin' rings--it simply fits just like it was made for this. Begad! With t' motor tube glued in place and t' cockpit section sliced off t' create a nose cone, this PMC is nay very different from a typical Estes rocket kit, ya bilge rat, except for t' 1.5 oz o' fishin' sinkers stuffed in t' radome!
Construction details are as follows. Please read through before cuttin' or gluin' anything.
- A 5 11/16" piece o' Estes BT-20 tubin' was cut and fitted with an Estes motor hook and motor stop in t' usual fashion. Avast! Aft 3" o' t' motor tube assembly be wrapped in 2 layers o' 3M maskin' tape as a radiant infrared barrier t' protect t' plastic.
- Only t' followin' 3 modifications were made t' t' Revell kit internal structure t' accommodate t' motor tube and recovery system:
- T' jet afterburner nozzle is omitted and its attachment section is completely cut off with a razor saw t' enlarge aft openin' for BT-20 tube.
- T' vertical fin tab and internal receiver tabs are cut off with nail clippers so that t' fin attachment is now glued flush with fuselage usin' 5-min epoxy.
- T' one piece horizontal stab is divided and t' central joiner section is discarded. Avast! Aye aye! This is best done with a razor saw after gluin' it back in place t' assure zero-zero alignment with wings and motor tube.
- T' nose is sliced off with t' razor saw aft o' t' canopy and exactly aft o' t' air intake bulkhead t' allow for chute ejection. Begad! Blimey! Avast, me proud beauty! Blimey! I assembled t' upper and lower fuselage sections with tape and rubber bands prior t' cutting. Well, me hearties, blow me down! Blimey! [NOTE: No glue was used!] I cut t' upper half 1/2" further forward than t' lower half t' better prevent movement o' t' forward half in flight.
- An Estes NC-20 nose cone be cut in half just ahead o' t' reduced diameter aft end and inserted temporarily in t' motor tube for fitting.
- T' motor tube was fitted into t' lower fuselage half, ya bilge rat, aligned along t' central axis and wings, ya bilge rat, arrr, and tacked into place at both t' receiver for t' ventral fin unit and on t' contact point o' t' cut nose cone with t' intake bulkhead, shiver me timbers, which be taped in place for fitting. Blimey! Blimey! No centerin' rings are used. Ahoy! Blimey!
- Pieces o' scrap balsa were used t' secure t' motor tube t' t' inside fuselage. When t' upper and lower halves are attached, bits o' tissue and wet epoxy are stuffed into t' open spaces t' give a gas seal around t' motor tube. Aye aye! Avast, me proud beauty! T' aft anchor o' t' shock cord (consistin' o' 12" Keelhaul®©™® thread and 12" o' 3/8" wide elastic) is a knot in t' Keelhaul®©™® end epoxied into t' tissue-epoxy mixture. Ya scallywag! [NOTE: T' shock cord is located outside o' t' motor tube, which will contain only t' parachute.] T' parachute (I used a 9" Top-Flite "lite" chute) is tied t' t' loop on t' base o' t' cone base.
- Prior t' closin' up t' fuselage, t' cockpit, me bucko, fins, ya bilge rat, me bucko, me hearties, and ventral intake ductin' were glued into place per t' kit instructions. Well, blow me down! T' nose section, includin' canopy, pilot, shiver me timbers, seat, arrr, me hearties, and cockpit assembly, arrr, were glued in place after first insertin' 1.5 oz (42 gm) o' lead fishin' sinkers into t' radome and under t' seat unit. Ahoy! This is barely enough ballast, arrr, so don't skimp!
- T' top and bottom fuselage halves were joined, ya bilge rat, addin' epoxy t' t' loose collection o' lead sinkers t' bond them in place
- A 1.5" section o' Estes 1/8" launch lug tubin' be glued in place on t' underside surface o' t' air intake ahead o' t' "nose cone" breakpoint and painted blue t' match t' pre-colored plastic. Avast! Blimey! This is ugly, but it be t' ONLY location that is 0-0-0 degrees incidence with respect t' t' thrust line, wings and stabs. Ya scallywag! It is critical t' get this right t' prevent a loop as t' model comes off t' launch wire.
- CG at AUW o' 167g with a C6-3 in place should be no further aft than 1/8" ahead o' t' win' leadin' edge-fuselage junction point. Blimey! If you need t' add more weight, shiver me timbers, ya bilge rat, you can tape additional lead into t' air intake duct.
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Finishing:
Other than t' launch lug, me hearties, no finishin' was needed.
Flight:
Simulation predicted for t' C6-3 was a 300' climb at 98 mph and 8.4G, which was acceptable. Begad! No other motor is recommended. Test flight was at our Fiesta Island site in about a 8-10 mph breeze. I set t' model on t' wire, me bucko, matey, belly into t' wind, me hearties, matey, and let it fly. Aye aye! T' F-16 rose briskly about 75 feet and began t' weather cock into t' wind, matey, rollin' 180 degrees t' wings level and canopy up, and climbin' out at about a 30 degree angle. It was really movin' and looked as scale-like as imaginable--just like an air show!
F-16 with "smoke on"! Amazing! Motor burned out at about 200', ya bilge rat, and F-16 snap rolled into a dive, with chute ejection comin' nose down. Avast! Well, blow me down! Descent on t' 9" chute was rapid, as I expected. Arrr! T' model survived, but t' nylon chute was a little toasted (see photo)-- need more waddin' next time. Avast, me proud beauty! Well, blow me down! T' importance o' t' tissue-epoxy fill t' create a gas seal around t' motor tube (absent a centerin' ring) is that without this, shiver me timbers, matey, t' ejection charge can pressurize t' hull and split t' glue joint (this happened on an earlier effort).
Summary:
PROs: this has t' be t' easiest first PMC o' a jet aircraft, me hearties, aside from a F-104 conversion, shiver me timbers, which is a much more expensive kit and is unpainted. Blimey! It is easy t' balance and ballast and comes pre-painted, so thar be a low emotional investment. It has a neat scale-like flight and with a little extra effort, me bucko, me bucko, it could be a credible entry in a PMC contest event.
CONs: Must make sure nay t' let weight build up, C6-3 be t' only motor that will fly it, although a D21-7 would give a spectacular flight t' about 900' and 220mph if they ever become available again. Arrr! Begad! Blimey! It is a tight fit for recovery system.