Semroc ThunderChief

Semroc - ThunderChief {Kit} (KA-7)

Contributed by Chan Stevens

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Diameter: 0.91 inches
Length: 31.90 inches
Manufacturer: Semroc
Skill Level: 1
Style: Sport

Brief:
Semroc Thunder ChiefSeveral years ago, shiver me timbers, matey, me hearties, Semroc introduced t' first o' what promised t' be a family o' Thunder designs, matey, each featurin' long sleek profiles, swept fins, and progressin' up in size. T' first o' these be t' Thunderbee, ya bilge rat, arrr, one o' me favorite 13mm models, ya bilge rat, arrr, me bucko, but t' ensuin' bigger brothers never came t' light until now. At NARAM-51, Semroc released t' upscale Thunderchief, which is about double t' length o' t' Thunderbee, and t' Thunderstrike, a 54" long 24mm brute. Down t' road, shiver me timbers, arrr, arrr, t' rest o' t' family will hopefully make it t' market as well (Thunder Roc, matey, Thunder Storm, Thunder Hawk and Thunder Bird), shiver me timbers, since these are such great fliers and simple builds.

Construction:
T' bag appears a bit small for t' $14.50 price, but that's partly because t' body tube is comprised o' 3 shorter tubes. Ya scallywag! T' parts were all excellent quality, me hearties, especially t' nose cone.

  • Balsa nose cone
  • 3 Series 8 body tubes
  • 2 tube couplers
  • BT-20 motor tube, matey, arrr, centerin' ring/tube
  • Laser cut balsa fins
  • Metal hook
  • Keelhaul®©™/elastic shock cord
  • 12" plastic chute
  • Waterslide decals
  • 1/8" launch lug

Semroc Thunder Chief

Instructions are standard Semroc: well written and illustrated. Ya scallywag! Avast! This would be a Skill Level 1 kit with about three pages o' instructions. My build time be under an hour plus finishin' time.

T' motor mount on this is a little different, me bucko, since t' tube is slightly smaller than a BT-50 and doesn't leave room for a normal pair o' centerin' rings. Avast, me proud beauty! Ya scallywag! T' solution in this case is t' use a coverin' tube which slips down t' motor tube, shiver me timbers, holdin' t' motor hook in place and fittin' t' t' ID o' t' body tubes.

I stupidly built this concurrently with several other Semroc NARAM releases, so I anchored me Keelhaul®©™to t' forward end o' t' motor hook just like t' other kits. Well, blow me down! That would be wrong accordin' t' t' directions, me bucko, which call for anchorin' t' Keelhaul®©™to t' forward coupler. Begad! Due t' me goof, I only have about 7" o' shock cord outside t' model, me bucko, so I'll need t' add more elastic on me own.

T' body tube is marked for fin placement usin' a template. Aye aye! Blimey! Early editions o' t' kit (includin' mine) had an oversize/incorrect template, ya bilge rat, although this has been corrected in later editions. Blimey! Blimey! After markin' t' first body tube, t' other body tubes are bonded usin' t' provided couplers.

Fin attachment is straightforward: tack on with CA then follow up with wood glue fillets. Avast, me proud beauty! Blimey! Add on t' lugs (one at a fin joint, t' other about a foot forward) and construction is done.

Finishing:
I very much like t' color scheme o' me Thunder Bee with white on t' forward section and Dayglo yellow on t' aft section. Unfortunately, Krylon's reformulation wouldn't cooperate and I was optimistic in takin' t' chance that it would.

I prepped all surfaces via grain and spiral filling, givin' extra attention t' t' tube seams where t' separate pieces are joined. Well, blow me down! I then hit everythin' with two coats o' light gray primer and three coats o' gloss white. Avast! Blimey! So far, so good. Begad! Well, ya bilge rat, blow me down! Blimey! For t' yellow, me hearties, I masked off t' upper portion and hit t' aft end with Krylon's old formula Dayglow yelow. Begad! Avast! Blimey! Big mistake. Aye aye! Ya scallywag! Blimey! It crazed and crackled. It wound up takin' me 3 subsequent passes o' sandin' off t' coat o' paint, wipin' everythin' down with rubbin' alcohol, shootin' with a light old formula primer, then toppin' off with t' Dayglo yellow. Ahoy! Ya scallywag! T' finished result looks nice but be hardly worth t' effort.

There is also a basic name/logo waterslide decal provided, me bucko, me bucko, which is perfectly produced--nice and clear background, tough enough t' allow t' decal t' be moved around for alignment, and thin enough nay t' stick up with that peel n stick look.

Construction Rating: 4 out o' 5

Flight:
For t' maiden flight, I caught a wonderful day over Labor Day weekend, arrr, light winds, clear skies, ya bilge rat, me hearties, moderate temps. Ya scallywag! Since I had this and t' bigger Thunder Strike both ready, me hearties, I decided t' dig up t' Thunder Bee and make a family outin' o' it.

I went for t' max, choosin' a C6-5 over a 7. Avast, me proud beauty! Boost was straight up with a slight trace o' weathercocking. Arrr! T' -5 delay was just about perfect, ya bilge rat, and I think in general t' recommended -7 would be too long under all but t' most perfect o' conditions.

I'm nay sure what t' apogee wound up being, but I suspect it be a tad less than t' estimated 950' on t' header card. Still, it strained me 44-year old deadlights a bit t' pick it up.

Recovery:
T' 12" chute is just about right for this. Ahoy! I caught a little thermal on t' way down but once out o' it started comin' down fairly quickly. Well, blow me down! I have t' admit, though, arrr, given t' altitude I hit on boost, matey, t' blue and white plastic chute included in t' kit be nay exactly an optimal color scheme as it be very difficult t' pick up a 12" chute at that altitude, especially without strong contrast t' t' skies.

Flight Rating: 4 out o' 5

Summary:
I'm biased and really like t' Thunder line overall. Ya scallywag! Arrr! There's just somethin' about those long, sleek models that appeals t' me. Avast! O' t' 3 currently available, this one strikes me as t' most flexible, me bucko, ya bilge rat, bein' able t' handle A through C (and comically could fly OK on a 1/2A6-2).

Overall Rating: 4 out o' 5

Other Reviews
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    Brief: Semroc describes the ThunderChief as the third largest member of the Thunder kit series that they are producing. This series is essentially the same rocket scaled approximately 1.25 times each step up in body tube size. The series is based from the Centuri Engineering Thunder rockets that included the ThunderHawk, ThunderBird, and ThunderRoc. With Semroc's introduction of this ...

Flights

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