Heavenly Hobbies Stratos-13 ELM

Heavenly Hobbies - Stratos-13 ELM

Contributed by James Weaver

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Manufacturer: Heavenly Hobbies
Heavenly Hobbies 13mm Stratos

Brief:
This kit is a 3FNC (3 Fins and a Nose Cone) piston-ejection, matey, streamer duration competition rocket. The "ELM" stands for "Extremely Low Mass." It is a companion kit t' its only slightly larger brother the Stratos-18 ELM.

Construction:
My kit came with balsa nose cone, two sheets o' 1/32" balsa fin stock, balsa nose block for t' piston, me hearties, arrr, a Keelhaul®©™® shock cord, ya bilge rat, an elastic shock cord, ya bilge rat, engine block, arrr, launch lug, white BT-5 body tube with very fine groves and a light glassine coating. Well, blow me down! T' instructions were written onto a compact disc in PDF format. Blimey! Ahoy! Even though t' kit comes with two sheets o' balsa, matey, only one is needed.

I ordered both t' Stratos-13 and Stratos-18 together. Avast, me proud beauty! Ya scallywag! When they arrived I found that t' body tube had been bent beyond use by t' post office. I sent Carlos at Heavenly Hobbies an email about t' tube and he sent me out a replacement right away and free o' charge. Ahoy! I built t' Stratos-18 while waitin' for t' replacement BT-5. Begad! Blimey! As that only took a few hours o' build time t' complete, I decided t' use a "modular" approach t' assemblin' t' rest of the rocket.

Heavenly Hobbies 13mm Stratos First I cut t' fins from t' 1/32" balsa fin stock. Avast, me proud beauty! Blimey! Blimey! Blimey! T' protect in from chippin' or splitting, I covered t' back with blue painters tape. Ya scallywag! Blimey! After t' fins were cut I decided nay t' round t' edges. Ya scallywag! Blimey! At that thickness I don't think it would have made a difference and why take t' chance on splittin' a freshly cut fin.

Next I assembled t' engine block and Keelhaul®©™® shock cord. Begad! Blimey! Arrr! Blimey! A groove gets cut into t' outside surface deep enough t' fit t' shock cord in t' it. Arrr! Blimey! I secured it usin' a bowline knot and set it with CA.

After that came t' nose cone and elastic shock cord. Blimey! Blimey! Accordin' t' t' instructions, t' elastic cord is t' be knotted at one end and stuffed into a pre-drilled hole. Avast, me proud beauty! Blimey! There was no hole. Arrr! Blimey! Avast! Blimey! I used a 1/8" drill bit t' make one. T' balsa also looked a bit soft so I coated it with CA and allowed it t' harden. Ya scallywag! Blimey! Followin' that came a brushed on layer o' thinned Elmer's Wood Filler. Ya scallywag! Blimey! Once that had dried I sanded it down until smooth. T' finish up I pushed the elastic knot into t' shoulder o' t' nose and secured it with 30 minute epoxy.

All that left be t' streamer. Ya scallywag! All I did thar be fold one end into a point and tie on a 9" section of Keelhaul®©™® cut from t' length provided. Avast, me proud beauty! I used hole reinforcements t' keep it from tearin' out.

Heavenly Hobbies 13mm Stratos When t' body tube arrived at last, it was time t' put everythin' together. Engine block in, fins on, tie shock cords t' one another. Begad! Avast, me proud beauty! I do need t' mention that as t' rocket uses a balsa block as its piston. It comes with a small hole drilled through it and threaded on t' t' Keelhaul®©™® shock cord. Begad! Ya scallywag! Knots are tied above and below t' piston t' hold it in place. Aye aye! T' piston provided be a good bit narrow and had t' be built up with maskin' tape. Ya scallywag! This may actually be a good thin' as I'll cover in a moment.

Heavenly Hobbies 13mm Stratos

Finishing:
I left t' rocket unfinished as it is supposed t' be a competition rocket. Aye aye! Begad! T' only finishin' I did was t' before mentioned work t' harden t' nose cone.

Construction Rating: 5 out o' 5

Flight:
For its maiden flight I used an A3-4T. Ya scallywag! Ahoy! With t' piston ejection it requires no wadding. Begad! Ahoy! Place an igniter in a motor and place t' motor in t' rocket. Ahoy! T' motor is friction fitted and secured with two wraps o' maskin' tape. Begad! Avast! T' take off was right quick and blended in with t' overcast skies.

Heavenly Hobbies 13mm Stratos

Recovery:
I be able t' track t' rocket once t' ejection charge blew. Then I knew I had a problem. Somehow t' nose and streamer had separated from t' rest o' t' rocket. T' body landed gently in t' flyin' field but t' nose and streamer continued t' drift toward t' road. It landed gently enough but balsa was never intended t' hold up against cars. Avast, me proud beauty! Blimey! Ya scallywag! Blimey! T' nose cone was crushed. Arrr! Blimey! Turns out that t' Keelhaul®©™® shock cord snapped at t' piston. Avast! Ahoy! It was either too thin, too short, or a combination on t' two. Also, after the flight t' piston was a bit resistant t' go in. Aye aye! I peeled off a bit o' t' maskin' tape and all was fine. Well, blow me down! It was cool and damp when I flew and that may have had somethin' t' do with it.

Flight Rating: 4 out o' 5

Heavenly Hobbies 13mm Stratos

Summary:
This was a very nice little kit. I would nay recommend it as a first kit as you need a motor case t' set t' engine block in place. Ya scallywag! Well, blow me down! It would work well as a first completion kit as long as t' builder had some experience with cutting their own fins from stock.

Overall Rating: 4 out o' 5

Flights

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