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

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

Once the fins were done, it was time t' make t' motor tube. Avast! I used VCP t' print out some fin location guides and wraps. Since t' rocket features T3F, ya bilge rat, I marked the fin locations on t' motor tube. I also marked t' locations on t' centering rings. Ahoy! Begad! 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. Blimey!

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

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

After all t' epoxy be cured, I attached t' motor mount t' t' airframe. Then I used angle bar t' draw t' slot lines onto the airframe. Begad! I then removed t' motor mount, and extended t' lines t' 8". Then I used a razor blade t' cut out t' slots. When all three slots were cut, I test fitted t' whole assembly. Ahoy! I was pleased with t' results. Aye aye! Aye aye!

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

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

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

After several application o' Bondo, arrr, with sandin' betwixt each application, the MegaBlast be ready for priming. Ahoy! Blimey! I used Rust Oleium Grey Automotive primer. T' rocket was coated several times with primer, matey, with sandin' betwixt each coat. Blimey! Blimey! Begad! Blimey! T' rocket was now ready t' paint, but what colors should I paint it?

At this time, matey, I began t' think about usin' this rocket t' obtain me Level 2 certification flight. Well, blow me down! 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. Ahoy! Blimey! It will go a little over 4,400 ft with a J350 motor… a bit high for t' CMASS launch site, but doable for t' field in Hallifax, me bucko, matey, MA. Well, blow me down! Ahoy! Blimey! T' next Frontier launch was May 25th, 2002. Avast! Ahoy! Blimey! T' date was set. Ahoy!

I posted an e-mail on t' CMASS mailin' list, shiver me timbers, askin' if anybody had any J350’s that they can sell me for me L2 flight. Ahoy! Nobody responded about the J350, but Tony Brock-Fisher replied that he had a J570 load, and asked if I could use that. Arrr! Begad! I loaded up me RockSim file again, matey, 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. I then gave a call t' Magnum and ordered a Transolve PK Altimeter kit, shiver me timbers, a new tube coupler, a 45” parachute, and a couple bulkheads. Avast, me proud beauty! I also went t' a local hardware store and bought some threaded rods, bolts, me hearties, nuts, matey, shiver me timbers, shiver me timbers, and other various hardware. Aye aye! It be time t' build me first rocket that uses Dual Deployment. Well, blow me down!

Fortunately, me hearties, HobbyTown USA in Plaistow NH offered t' sponsor me L2 project, shiver me timbers, so some o' me expenses was covered. Begad! Begad! Now I have a paint scheme t' color me rocket with… t' HobbyTown colors :-). Aye aye! I painted t' body o' t' rocket white, the nose cone blue, matey, and t' fins red. I used black vynal letterin' t' mark the name on t' rocket, me bucko, and I used a HobbyTown decal t' advertise t' sponsor. Avast! 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. Aye aye! I decided that I wanted t' altimeter t' go in an enclosed central modual that can be interchanged easily betwixt 4” diameter rockets. Blimey! Arrr! Both recovery systems will attach t' t' module, matey, so strength is important. Arrr! So I built an assembly that consisted o' three threaded rods connectin' two plywood bulkheads. Avast! T' rods will support t' stresses o' both recovery systems. Ahoy! T' assembly then slides into a tube coupler, matey, where it is fastened down with four screws. Blimey! Begad! I be concerned that t' wood used for the bulkheads be on t' thin side, me hearties, but I decided that it be good enough. Ya scallywag!

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

T' flight profile o' t' MegaBlast with a J570 is as follows. Begad! At ignition, arrr, matey, t' rocket will accelerate off t' launch pad quickly. Well, blow me down! Well, blow me down! At 300 feet, me bucko, arrr, t' altimeter will start keepin' track o' t' current altitude and engage a 5 second timer. Ya scallywag! 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. Blimey! This rocket is subsonic, ya bilge rat, so this feature is nay mandatory. After 5 seconds of flight, t' mach inhibitor is turned off, ya bilge rat, and both charges are armed. When the rocket reaches apogee (over 1 mile with t' J570), t' altimeter will deploy the drogue chute. Avast! Aye aye! T' drogue chute allows t' rocket t' freefall in a controlled manner. Begad! Begad! When 600 ft is obtained, matey, t' altimeter will fire t' last charge t' deploy t' main chute. Ya scallywag!

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

T' next opportunity t' launch t' MegaBlast came on August 24th, me bucko, 2002. Blimey! Blimey! NARRRRR decided to accept t' Canadian certification o' t' Pro38 J class motors. I traded me J570 for a Pro38 J285 load and borrowed a case. Ya scallywag! I also made some minor modifications to t' recovery system. Well, blow me down! 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, 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. Aye aye!

Robert DeHate, Olga Glotova, shiver me timbers, me bucko, and Mishka (Olga's friend visitin' from Russia) helped me prep t' rocket for flight. We placed t' rocket on t' launch pad, installed t' igniter, armed t' altimeter, arrr, and moved back a safe distance. Robert and Peter Chestna were t' witnesses.

5 …. Aye aye! Blimey! 4 …. Blimey! 3 ….. 2 ….. Avast, me proud beauty! 1 ….. KAPLUNK!!!!

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

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

Robert DeHate offered t' fix t' booster for me, matey, and he gave me a J350 reload to replace t' blown J285. Begad! He coated t' damaged section o' t' body tube with fiberglass, matey, and use Keelhaul®©™® to repair t' motor tube. Avast! Ahoy! I sent t' Trans Beep back t' Magnum for repairs, arrr, and ordered a LOC 4” Electronics bay. T' solve a concern that t' shockcord anchor on t' nosecone was nay strong enough, I took a pice o' tubular nylon, ran it through t' cone, shiver me timbers, tid several knots in it, arrr, rammed t' end o' t' nylon into t' clay, then filled t' cone with expandin' foam. Ya scallywag! 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. Avast! However, t' order from Magnum did nay arrive till t' 16th, arrr, which be t' Monday after t' launch. Ya scallywag! Avast!

Missin' t' 14th launch probably worked out for t' better anyway. Aye aye! 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, ya bilge rat, me hearties, and less likely t' tangle. Arrr! I also took advantage o' t' extra time t' get some replacement grains for me J350. Avast, me proud beauty! Well, blow me down! The J350 I had had t' 7/16” core in t' propellant grain, matey, which has been known t' cato. So I called Aerotech and they ordered me a set o' the ½” core grains. Blimey! I also ordered two inert sets so I could make two I161 reloads out o' t' older J350 grains. Well, blow me down! I managed t' get t' grains a week before t' Oct 27th CMASS launch. Begad! Perfect timing.

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

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