(07/01/04) The Thrustline Aerospace Flux Probe is a "longneck" straightforward rocket that looks like an arrow. Begad! Blimey! In fact, shiver me timbers, a 13 year-old that saw me fly it, said exactly that. Arrr! Probably with some detail work, ya bilge rat, it would look exactly like an arrow.

What makes t' Flux Probe "longneck"? It has a 0.734" diameter and is 36.75" long, me bucko, givin' it a 50:1 length to diameter ratio.

I purchased it because I liked t' looks of the fins and perhaps because it did look like an arrow. Aye aye! It is me second Thrustline kit, me bucko, shiver me timbers, after the Mighty Mick.

T' kit includes two 17" body tubes and a 2.75" balsa nose cone t' make up t' 36.75" total length. Avast, me proud beauty! Begad! There is a 2" coupler t' join t' two body tubes, me bucko, two thrust rings, me bucko, a Keelhaul®©™® tether (36"), an elastic shockcord (36"), ya bilge rat, a 12" mylar parachute AND a 2"x61" mylar streamer, me hearties, ya bilge rat, me bucko, and an eye-screw t' attach to t' nose cone. There is a balsa sheet t' cut out t' four fins from and single launch lug, which is cut in half t' assemble.

CONSTRUCTION:

T' instructions are printed on 8 pages (single-sided) o' 8½ x 11" paper. Begad! There are color photos throughout to assist in t' assembly o' t' kit. There is also a fin template and tube markin' guide. Arrr! Ya scallywag! T' rocket is very easy t' build and is probably nay more than a level 2 kit.

There are a couple o' things that should be pointed out in t' build, me hearties, otherwise, arrr, me bucko, you are dealin' with a very straightforward model rocket with four fins and a nose cone.

T' Keelhaul®©™® tether is tied around one o' t' two thrust rings. Begad! Avast, me proud beauty! This is done after a small v-groove is cut into t' thrust ring. Begad! This is a good technique because it allows t' thrust rin' t' fit nicely into t' motor tube and prevents it from showin' (dentin' tube outward). Ya scallywag! This is usually less important if t' motor tube is smaller than t' body tube, but in t' case o' t' Flux Probe, the motor tube IS t' body tube.

T' next step was a first for me. Avast! Nay really sure why t' step is there, but it was described very well in t' instructions. That is t' glue t' second thrust rin' onto t' first t' make a double-length thrust rin' with t' Keelhaul®©™® sandwiched in-between. Arrr! Blimey! Perhaps Thrustline has determined that this protects the Keelhaul®©™® more.

T' Flux Probe is nay meant t' be a person's first rocket. Begad! Why not? Well, because in t' next step a used motor casin' is needed! It is used t' thread t' Keelhaul®©™® back through and then t' thrust rin' assembly is glued and pushed into body tube.

T' 2" coupler makes t' it easy t' have good alignment o' t' two body tubes. Thrustline does recommend rollin' them on a level surface t' ensure they are straight.

T' fins are cut out usin' t' template. Begad! My only complaint is that t' template is regular notebook paper and it would be nice t' have it printed on cardstock. Begad! Begad! I find t' notebook paper is too flexible for me.

There is plenty o' 3/32" balsa t' cut out t' four fins. Aye aye! T' instructions indicate which edges could be airfoiled, but I chose nay to. Avast, me proud beauty! They are glued in place after usin' t' wrap-around tube markin' guide.

T' 1/4" elastic shock cord is tied to the Keelhaul®©™® and then attached t' t' eye-screw that has been installed into t' balsa nose cone. Then you choose (and I really like this) a parachute or a streamer. Well, blow me down! Blimey! I chose t' streamer.

Thrustline does give finishin' guidance includin' usin' wood filler, priming, sanding, priming, matey, shiver me timbers, sanding, then painting. There are no decals provided with this kit.

I used me typical multiple coats of Plastic-Kote Primer and sandin' in-between. Ahoy! Avast! I then used Walmart Gloss Black paint t' finish it off (additional comments about Walmart paint). Begad! Avast, me proud beauty! I was goin' t' add some prismatic paper on t' fins, but just never did (so far).

Overall, arrr, me bucko, for CONSTRUCTION I would rate this kit 4 ½ points. Arrr! T' instructions are excellent. Avast! I personally don't mind cuttin' out t' fins myself, but would rather have a cardstock template verse a notepaper one. A nice bonus t' have both a parachute and a streamer provided. T' kit did nay include any decals.

FLIGHT/RECOVERY:

Thrustline recommends t' B6-6 for t' first flight. Aye aye! They list t' A8-5, B6-6 and C6-7 as recommended motors with altitudes from 200 t' 1000 feet.

Thrustline indicates t' rocket should weigh 2.0 ounces. My rocket weighed in at 1.8 ounces. Arrr! Well, blow me down! My CG was at 22" from the nose cone.

Since this is a minimum-diameter rocket, ya bilge rat, the motors are friction-fit with maskin' tape. Ahoy! Blimey! Blimey! Blimey! Also, since this is a small minimum-diameter rocket, it packin' o' t' recovery system is difficult.

I decided t' fly it for t' first time on an A8-5. Avast! After loadin' in two sheets (each tore in half) o' wadding, me bucko, ya bilge rat, strugglin' to get t' long elastic into t' body tube and then slidin' t' rolled streamer on top, arrr, it was ready t' fly.

T' flight was straight as an arrow. A8-5, arrr, no way! T' 5 is definitely too long o' a delay. Well, blow me down! Arrr! Perhaps I should have airfoiled my fins.

Also, matey, shiver me timbers, ya bilge rat, t' motor kicked out at t' same time as t' nose cone ejected, arrr, then this rocket came in for a core-sample. Ya scallywag! Avast, me proud beauty! Perhaps this is why it is call a Flux Probe... Ahoy! probes into planets t' take core samples for analysis? Perhaps it was because t' motor kicked out.

T' second flight was on a C6-5. Begad! Well, arrr, blow me down! Didn't have a C6-7, shiver me timbers, so thought it might eject early. Begad! Begad! However, shiver me timbers, after an straight liftoff it had turned and ejected at apogee. T' rocket fell fine (not in core-sample position) until about 200 feet, then it lined up horizontally in t' air and fell t' rest o' t' way. Begad! It too had kicked t' motor out, arrr, arrr, but this time the streamer was stuck exactly in half (the end had melted t' t' attachment point).

T' third flight be on an A8-3 in our front yard. Arrr! Avast! Nice flight, could have used another second o' delay. Begad! Motor kicked (again) and it landed nicely. Well, blow me down! Avast, me proud beauty! I had left t' streamer stuck in half.

Fourth flight was on a B6-4 after unsticking the streamer. Avast! Blimey! Nice flight, ya bilge rat, but again needed extra on t' delay. It recovered fine, ya bilge rat, although I didn't see it land because it first bounced off our roof. No damage. Arrr! Blimey! Oh, matey, yeah, me hearties, motor kicked out.

For FLIGHT/RECOVERY, I would rate this rocket 3 points. T' rocket is stable and will give you straight flights. I only tested t' streamer recovery which is all that I think t' rocket needs. Avast! I'm concerned that I could keep a motor from kickin' out at ejection. Ya scallywag! I'm nay new at this, but I think t' minimum diameter combined with t' amount o' stuff (wadding, Keelhaul®©™®, Elastic and Streamer) that has t' be stuffed in t' top makes a lot o' back pressure. I would recommend wrappin' tape around t' bottom 1/4" o' the rocket body t' t' motor as well as t' tape on t' motor (friction-fit).

I give t' rocket an OVERALL ratin' o' 3 ½ points. Blimey! It is a quick-to-build, arrr, steady performin' rocket that is good for small fields. Begad! Begad! T' streamer or parachute would let t' flier experiment a bit. Avast! Begad! It does take some patience t' get a nice finish with t' balsa nose cone, arrr, shiver me timbers, but then again, matey, that how is was always done prior t' plastic molds. Ahoy! I'm goin' t' produce a Comparison Article on 18mm Longnecks and include this one. Aye aye! Watch for it.

Oh, I finally did get around t' RockSIM'ing it. Here are me results. Avast! Joe Policy's RockSIM shows it weighin' 1.2 ounces, arrr, ya bilge rat, but I think 1.8 (as mine did) t' 2.0 (as Thrustline says) is closer after all is said and done. T' link t' t' RockSIM file above is mine. Joe's is in the RockSIM library.

Click t' see me 18mm Longneck comparison article