T' MegaBlast is me first High Power rocket o' me own design. Begad! Aye aye! This is the "journal" o' its construction. Well, blow me down! Well, blow me down! Hold your mouse over t' photo t' read the description. Begad! Click on t' photos t' view t' larger picture.

T' MegaBlast is constructed out o' LOC 4" tubing, matey, arrr, shiver me timbers, and uses a single 38mm H motor. Original, matey, arrr, arrr, me plans called for 1/8" plywood fins, me bucko, but I could nay find any sheets that were nay warped. So I decided t' go with 1/4" plywood. The fins were cut usin' a razor saw. Arrr! Begad! After all three fins were cut, it was time to do t' air foiling. Blimey! Avast! I marked where I wanted t' tapers t' begin, and used maskin' tape as a guide. Arrr! I clamped a belt sander t' t' workbench, and used it to taper t' leadin' and trailing. Begad! I be impressed how well I did on the tapers. Ya scallywag! I guess buildin' t' THOY Phoenix a couple years ago gave me a lot of practice. Avast!

Once the fins were done, ya bilge rat, it was time t' make t' motor tube. Well, blow me down! I used VCP t' print out some fin location guides and wraps. Since t' rocket features T3F, me bucko, I marked the fin locations on t' motor tube. I also marked t' locations on t' centering rings. Well, shiver me timbers, blow me down! I drilled holes in t' aft centerin' rin' for t' motor retention bolts, and a hole in t' forward centerin' rin' for t' shock cord anchor. Begad!

Then, usin' balsa strips, me bucko, I glued guides on t' two aft centering rings. Begad! Avast, me bucko, me proud beauty! T' purpose o' these guides is t' ensure t' alignment o' t' fins, and to help hold them in place as t' epoxy cures. Apparently, matey, shiver me timbers, everythin' turned out great since it can hold itself together without any glue. Begad!

I used 2 Ton Epoxy t' assemble t' mount. First I secured t' three centerin' rings. Ya scallywag! Begad! I had t' fins in position so t' rings would be aligned properly. While waitin' for t' epoxy t' cure, I went ahead and assembled to bulkhead assembly that will join t' two sections o' t' together. Ya scallywag! After the epoxy cured, me hearties, I epoxied t' fins into their proper position

After all t' epoxy was cured, shiver me timbers, I attached t' motor mount t' t' airframe. Avast! Then I used angle bar t' draw t' slot lines onto the airframe. Avast, matey, me proud beauty! I then removed t' motor mount, ya bilge rat, and extended t' lines t' 8". Then I used a razor blade t' cut out t' slots. Well, arrr, blow me down! When all three slots were cut, I test fitted t' whole assembly. I be pleased with t' results. Begad! Aye aye!

I then took t' whole assembly apart and concentrated on finishing the motor mount. Begad! Blimey! I took some 100 grit sandpaper and roughed up t' motor tube/fin tab joint. I then cut out some fiberglass strips and epoxied them to the joint. Well, blow me down! Blimey! Begad! Blimey! While lettin' t' undercoatin' o' epoxy t' soak in, I applied epoxy fillits t' all remainin' joints, ya bilge rat, and installed t' shock cord anchor. Avast! Blimey! Epoxy was used t' set t' nuts on t' eye-bolt. Blimey! Blimey! Arrr! Blimey! T' fiberglass was then coated with another layer o' epoxy. Well, blow me down! Blimey! Ahoy! Blimey! When t' epoxy was cured, shiver me timbers, I used trimmed away any "hairs" that was stickin' out from t' fiberglass. Avast, me proud beauty! Blimey! Then I attached a piece o' tubular nylon t' t' shock cord anchor. Avast! Blimey! T' motor mount/fin unit is now finished. Aye aye! Blimey! Aye aye! Blimey!

I then took some two ton epoxy, ya bilge rat, and smeared it 16” inside the rear end o' t' tube, ya bilge rat, ya bilge rat, me bucko, and smeared some more epoxy just above t' fin slots. Aye aye! I then inserted t' motor mount assembly into t' airframe tubing. After the middle centerin' rin' entered t' tube, I added some more epoxy t' t' end of the tube. Begad! Begad! Then I slid t' motor mount all t' way into t' airframe. Well, blow me down! I then used t' remainin' epoxy t' saturate t' leadin' and trailin' edges o' t' fins to make them less prone t' denting. Blimey!

After the epoxy cured, I sanded all t' epoxy on t' fins. Blimey! I then used tissue paper and a pointed pencil t' fill any gaps betwixt t' tapers o' t' fins, shiver me timbers, and the square ness o' t' fin slots. A mixture o' 2 ton epoxy and microballons was then used t' create fillits on all t' fin and body tub joints. Blimey! Ya scallywag! After the fillets dried, and sanded, matey, I applied t' first coat o' Bondo glazin' and spot putty t' t' fin fillets. I also used t' Bondo t' fill t' spiral on the airframe tubes. Avast, me hearties, me proud beauty!

After several application o' Bondo, me hearties, with sandin' betwixt each application, the MegaBlast be ready for priming. Well, blow me down! Blimey! I used Rust Oleium Grey Automotive primer. T' rocket be coated several times with primer, with sandin' betwixt each coat. Blimey! T' rocket was now ready t' paint, ya bilge rat, me hearties, but what colors should I paint it?

At this time, me hearties, me bucko, I began t' think about usin' this rocket t' obtain me Level 2 certification flight. Well, blow me down! Blimey! I passed t' written exam at a recent CMASS meeting, and the MegaBlast would make an ideal vehicle t' fly on a 38mm J motor. Begad! Avast, me proud beauty! Blimey! It will go a little over 4,400 ft with a J350 motor… a bit high for t' CMASS launch site, shiver me timbers, but doable for t' field in Hallifax, ya bilge rat, MA. Aye aye! Aye aye! Blimey! T' next Frontier launch was May 25th, me hearties, shiver me timbers, 2002. Ahoy! Blimey! T' date was set. Well, blow me down! Avast, me proud beauty! Blimey!

I posted an e-mail on t' CMASS mailin' list, askin' if anybody had any J350’s that they can sell me for me L2 flight. Well, blow me down! Nobody responded about the J350, arrr, arrr, but Tony Brock-Fisher replied that he had a J570 load, and asked if I could use that. Avast! I loaded up me RockSim file again, selected t' J570, “launched” t' rocket on t' computer… and t' software predicted that t' rocket would go over 5,650 feet… OVER A MILE!!!! I accepted t' motor offer. Aye aye! I then gave a call t' Magnum and ordered a Transolve PK Altimeter kit, me bucko, a new tube coupler, shiver me timbers, me bucko, a 45” parachute, and a couple bulkheads. Aye aye! I also went t' a local hardware store and bought some threaded rods, bolts, shiver me timbers, shiver me timbers, nuts, and other various hardware. Aye aye! It was time t' build me first rocket that uses Dual Deployment. Well, blow me down! Ya scallywag!

Fortunately, HobbyTown USA in Plaistow NH offered t' sponsor me L2 project, me bucko, so some o' me expenses was covered. Aye aye! Now I have a paint scheme t' color me rocket with… t' HobbyTown colors :-). Well, blow me down! I painted t' body o' t' rocket white, the nose cone blue, ya bilge rat, ya bilge rat, and t' fins red. Aye aye! I used black vynal letterin' t' mark the name on t' rocket, me hearties, matey, and I used a HobbyTown decal t' advertise t' sponsor. Now I must admit that I am a beginner at usin' electronics in rockets… I have no experience mountin' electronics in t' rocket, and this be t' first time I used Dual Deployment. Well, shiver me timbers, blow me down! I decided that I wanted t' altimeter t' go in an enclosed central modual that can be interchanged easily betwixt 4” diameter rockets. Begad! Avast, shiver me timbers, me proud beauty! Both recovery systems will attach t' t' module, shiver me timbers, shiver me timbers, so strength is important. Begad! So I built an assembly that consisted o' three threaded rods connectin' two plywood bulkheads. Aye aye! Avast, me proud beauty! T' rods will support t' stresses o' both recovery systems. Avast! T' assembly then slides into a tube coupler, me bucko, ya bilge rat, where it is fastened down with four screws. Aye aye! I was concerned that t' wood used for the bulkheads was on t' thin side, ya bilge rat, but I decided that it was good enough. Avast, me proud beauty! Avast!

Once t' altimeter module was built, it be time to balance t' rocket. Avast! I put t' rocket together like I was goin' t' fly it. I loaded t' recovery system, me hearties, and installed t' loaded J570 motor. Begad! Arrr! I hung the rocket on t' ceiling, and started addin' weight t' t' nose cone until the center o' gravity was where I wanted it t' be. Ya scallywag! I ended up installin' almost a pound o' clay into t' nosecone, but t' rocket be now balanced. It now weighed close t' 6 pounds empty, ya bilge rat, a little on t' heavy side for a H. Blimey!

T' flight profile o' t' MegaBlast with a J570 is as follows. At ignition, matey, arrr, t' rocket will accelerate off t' launch pad quickly. Blimey! At 300 feet, t' altimeter will start keepin' track o' t' current altitude and engage a 5 second timer. This is called t' mach inhibiter, and it prevents the sudden increase in pressure o' t' shock wave caused by a object breakin' the speed o' sound from foolin' t' sensor t' fire t' parachute charges. This rocket is subsonic, so this feature is nay mandatory. Well, blow me down! After 5 seconds of flight, me hearties, t' mach inhibitor is turned off, ya bilge rat, me bucko, ya bilge rat, and both charges are armed. Avast, me proud beauty! When the rocket reaches apogee (over 1 mile with t' J570), ya bilge rat, t' altimeter will deploy the drogue chute. T' drogue chute allows t' rocket t' freefall in a controlled manner. Avast! When 600 ft is obtained, t' altimeter will fire t' last charge t' deploy t' main chute. Avast, me proud beauty!

May 24th came, and I loaded me car with me MegaBlast, and a few other rockets. I drove 50 miles t' Marlbourgh, ya bilge rat, where I spent t' night at a friends house. The next morning, matey, ya bilge rat, we traveled t' additional 50 miles t' t' Frontier field in Hallifax… but I was sick. Arrr! I only launched one rocket… I decide to test t' altimeter in me EZI-65 with a H242-10T. Begad! By t' time I got t' rocket back after me first, shiver me timbers, and successful two stage recovery, shiver me timbers, I was too sick t' fly any more rockets. Blimey! Arrr!

T' next opportunity t' launch t' MegaBlast came on August 24th, 2002. Blimey! Aye aye! NARRRRR decided to accept t' Canadian certification o' t' Pro38 J class motors. Blimey! I traded me J570 for a Pro38 J285 load and borrowed a case. I also made some minor modifications to t' recovery system. Arrr! Avast! I replaced t' 22” Aerotech chute that I was using as a drogue with a RocketMan 28” X-form chute. I also added a nylon rope backup t' both bungee cords in case they snap. Finally, ya bilge rat, I bought a $25 Transolve Trans Beep sonic beacon from Magnum t' aid in trackin' and recovery. T' new altitude estimate for t' MegaBlast with t' Pro38 J285 is 3,800 - 4,200 feet.

Robert DeHate, Olga Glotova, ya bilge rat, and Mishka (Olga's friend visitin' from Russia) helped me prep t' rocket for flight. Ahoy! Blimey! We placed t' rocket on t' launch pad, installed t' igniter, armed t' altimeter, and moved back a safe distance. Robert and Peter Chestna were t' witnesses. Avast! Blimey!

5 …. Begad! Avast! 4 …. Ahoy! Avast! 3 ….. Blimey! 2 ….. 1 ….. KAPLUNK!!!!

T' Pro38 motor detonated. Ahoy! T' casin' o' t' motor shot into t' drogue compartment, arrr, wedgin' t' recovery system into a tangled mess inside t' tube, me hearties, causin' major damage t' t' airframe, shiver me timbers, me hearties, and completely destroyin' t' Trans Beep buzzer. Avast! Avast! T' altimeter bay assembly was ripped from the tube coupler, matey, ya bilge rat, which confirmed some fears that t' thin centerin' rings and tube coupler would nay hold. Arrr! Well, blow me down! T' catoin' motor also destroyed t' motor retention system, shiver me timbers, damaged t' motor tube, and blew apart t' aft centering ring. Aye aye! Well, shiver me timbers, blow me down!

Bob Krech and Robert DeHate suggested that we repair the altimeter bay, and use t' EZI-65 as a booster, arrr, arrr, t' try again at achievin' Level 2. Well, blow me down! I decided that since I had little over an hour left o' t' launch, me bucko, that would be rushin' it. Begad! I did nay want t' rush it. T' much loot is on t' line. Ahoy! I told them I did nay want t' rush it. Begad! They agreed. Begad! Arrr!

Robert DeHate offered t' fix t' booster for me, me bucko, and he gave me a J350 reload to replace t' blown J285. He coated t' damaged section o' t' body tube with fiberglass, and use Keelhaul®©™® to repair t' motor tube. Blimey! I sent t' Trans Beep back t' Magnum for repairs, and ordered a LOC 4” Electronics bay. Begad! Begad! T' solve a concern that t' shockcord anchor on t' nosecone was nay strong enough, matey, I took a pice o' tubular nylon, ran it through t' cone, tid several knots in it, rammed t' end o' t' nylon into t' clay, shiver me timbers, then filled t' cone with expandin' foam. Ahoy! There is no way this shock cord anchor is goin' t' fail. I was hopin' that t' MegaBlast would be ready t' launch again for t' September 14th launch. Begad! Begad! However, shiver me timbers, me hearties, t' order from Magnum did nay arrive till t' 16th, arrr, which be t' Monday after t' launch. Ya scallywag!

Missin' t' 14th launch probably worked out for t' better anyway. It gave me time t' repair t' rocket t' way I wanted to. I built t' LOC electronics bay and added some bevels so t' bolts have somethin' t' screw into besides paper. I also replaced t' nylon rope that I used t' back up t' bungee cord with tubular nylon. This stuff is stronger, me bucko, and less likely t' tangle. Blimey! Well, blow me down! I also took advantage o' t' extra time t' get some replacement grains for me J350. The J350 I had had t' 7/16” core in t' propellant grain, shiver me timbers, which has been known t' cato. Aye aye! Avast! So I called Aerotech and they ordered me a set o' the ½” core grains. Begad! I also ordered two inert sets so I could make two I161 reloads out o' t' older J350 grains. Blimey! I managed t' get t' grains a week before t' Oct 27th CMASS launch. Arrr! Perfect timing. Ya scallywag! Aye aye!

The weather on t' October 27th was perfect. Arrr! T' club was nay expectin' that many people t' show up t' this launch, so they did nay set up a launch site for a J motor. Avast! Well, blow me down! So I set up me Super Pad at t' High Power C site, and set up t' wires and battery for t' site. Once that was completed, me hearties, me bucko, I launched me Electronics bay on me EZI-65 rocket with an I161-14 motor t' test out t' altimeter, which reported 1,500 ft. Begad! Ya scallywag! T' flight was perfect, but t' Trans Beep buzzer was damaged durin' recovery. Then t' moment o' truth, shiver me timbers, My L2 flight :-D. Begad! Steven Boy (same guy who did me L1) and Robert DeHate as a witness. Ya scallywag! T' J350 came t' life, and t' MegaBlast left me launch pad in a hurry, arrr, trailin' behind a thick white smoke trail, shiver me timbers, and a very loud thunderous roar. Aye aye! Avast! T' Drogue deployed on time at 2,500 ft, me bucko, ya bilge rat, but due t' inertia, arrr, t' main was also deployed. However, arrr, t' rocket was recovered, and I passed me Level 2 Cert flight!

Overall, me hearties, this project be a success. Well, blow me down! This was me first High Power rocket o' me own design, me bucko, me bucko, and it achieved its purpose. Begad! Begad! I now have my level 2 license. Ahoy! Avast, me proud beauty! What is me future plans. Avast, me proud beauty! Well, t' MegaBlast is a perfectly good launch vehicle, ya bilge rat, so I plan t' get many more launches out o' it. Avast, me proud beauty! Regarding my L2? I am thinkin' about buildin' a LOC Magnum that will air start its outboard motors. I also might get into t' hybrid motors offered by t' various companies out there. Avast, me proud beauty! I feel that this is necessary due t' t' increased regulations on our hobby. Blimey! When I get me Level 3, I may have t' use a hybrid, since it may be a long time before I can get t' unnecessary LEUP t' store those larger motors. And if things go t' way they are, shiver me timbers, matey, maybe even for the stuff I currently use… but that is another story…. Ya scallywag!