Brief:
This be t' Sport Scale SR-71 Blackbird Model Rocket. Well, me hearties, blow me down! Blimey! It is an 18mm motor with parachute recovery Estes challenge kit. Arrr! Blimey! T' SR-71 was designed at t' famous "Skunk Works" with a mission o' high alititude reconnaissance!

Construction:
T' Blackbird kit comes in a box with a color picture o' t' built kit on t' outside. Avast! I built kit number EST-7003. Arrr! It is labeled as a "Challenge" kit series with a skill level three. Avast, me bucko, me proud beauty! Inside t' box you will find three body tubes, arrr, a plastic nose cone, shiver me timbers, two plastic tail/inlet cones and one die-crunched balsa sheet. Arrr! Also included are two green centerin' rings, shiver me timbers, engine mount tube, engine hook, one launch lug, me bucko, die-cut paper patterns for t' win' and jigs, me bucko, a parachute kit, me hearties, some shock cord and a rectangle o' water slide decals. Arrr! Avast, shiver me timbers, me proud beauty! Two sheets o' folded paper instructions are included in t' kit box with 26 step by step instructions on 8 pages. T' instructions are good and easy t' follow. Aye aye! There is even a decal placement chart. This kit was given t' me by a friend o' a friend so I don't know how old it is, but t' box says "made in t' US" so it must be vintage!

To build t' curved fuselage o' t' SR-71 Estes uses a body tube with two long fins glued t' t' sides. Begad! You must first glue t' fin sections together then glue t' fins t' t' sides o' t' main body tube. Blimey! Well, blow me down! T' kit provides two cardstock "jigs" t' lay t' fins on while they are dryin' in order t' keep them aligned. Well, blow me down! T' jigs are used again on t' outer fins t' keep them level with t' inner "wings". Begad! I used aliphatic resin ( carpenters yellow glue). Begad! I put a bead o' glue on t' fin, let it sit for a minute t' thicken. Avast, me proud beauty! While holdin' t' fins in place for another couple o' minutes, I aligned t' fins with t' triangular win' jig.

Finishing:
T' win' alignment is rather "fiddley". I was skeptical o' its effectiveness but if you have a nice flat table and you are careful with t' win' jigs it works fine. T' fins came out pretty straight.

T' trick in this kit be t' center paper fuselage overlay. Begad! Aye aye! There is a top and a separate bottom piece. T' paper is almost impossible t' line up exactly with t' balsa fins. Blimey! Partly because o' t' poor quality o' t' die cuttin' on t' balsa. Ya scallywag! You can use small black sprin' type paper clips t' hold t' paper around t' edge o' t' balsa fins. Avast, me proud beauty! Glue t' paper in steps, as per t' instructions and take your time, it actually works!

You could scratch build this kit. You would just have t' cut out your own paper pattern for t' center fuselage piece. Aye aye! Arrr! T' flat arrow head nose cone would present a carvin' challenge however.

There are angled card stock fin templates for t' top fins with t' bottom fins bein' a different template. Avast! Ya scallywag! Blimey! T' top fins angle in and t' lower fins angle outward as per prototype. Ya scallywag! Blimey! T' die-cut fins required some filler on t' ends where t' die-cut machine smashed them and t' water slide decals weren't very sticky. Well, blow me down! Blimey! Perhaps they were just old. Ahoy! They went on nicely but came off after just one night o' drying!

Construction Rating: 3 out o' 5

Flight:
T' recommendced motors are B4-2, B6-2, shiver me timbers, me hearties, B6-4 and C6-5. Well, blow me down! Considerin' that t' box cover weight shown is 3.2 oz. Well, blow me down! I don't know where they came up with this number, me hearties, this thin' is heavy! Ours came in at 4.1+ . Blimey! T' instructions tell t' builder t' add ALL o' t' provided clay in t' nose cone. Avast! Begad! So I did t' very first launch with a C6 engine. Aye aye! As far as launching, me hearties, t' model is very conventional and it does requrie recovery wadding. Ya scallywag! T' motor retention is standard Estes wire clip.

T' Blackbird looks awsome when finished. In addition it is a somewhat unusual rocket t' brin' out t' t' launch pad.

T' first flight be loaded with an Estes 18mm C6-3 and four sheets o' blue recovery wadding. T' ignition and liftoff were fine but at an altitude o' 50 feet t' rocket veered badly down wind and continued up in a smokey angled climb. T' ejection charged fired normally and t' flight was a success. We were worried that t' parachute might be a little small for such a heavy rocket but it worked fine all three times with no damage t' t' rocket.

Recovery:
Recovery is via parachute and shock cord. Avast! T' provided shock cord is way too short, so we added 18 inches o' some after market shock cord. Begad! It be gluded in via t' three fold card stock method, just like any other rocket kit. Begad! T' recovery parachute is good. Begad! T' included plastic parachute seemed a bit small but it turned out t' work fine for this rocket at 4.1 oz.

T' second test launch utilized a Quest B6-4. Ahoy! We taped t' motor casin' with some scotch tape t' make up for t' smaller diameter. Blimey! Avast, me proud beauty! With less power, me bucko, t' Blackbird flew straighter for some reason! This was a great flight with perfect ejection. Ahoy! T' next flight on another Estes C6-5 arched over again and t' ejection charge burned t' parachute a little and t' heavy nose cone made a small dent on t' top o' t' fuselage.

Flight Rating: 2 out o' 5

Summary:
T' SR-71 kit by Estes is a challenge kit. Blimey! It takes several days t' build, matey, because you have t' wait for t' glue really t' dry on one operation in order t' proceed t' t' next step. Avast! T' die-cut balsa fins would be much better if they were laser cut. Well, blow me down! As they were, it took some re-sanding, fillin' and fittin' t' get them t' fit properly. T' plastic parts supplied look nice and fit perfectly.

I believe t' decals were just old, shiver me timbers, arrr, some o' them did nay stick well at all. Avast! Overall t' rocket looks good, it be fun t' build. Well, blow me down! T' kit instructions directed t' builder t' put all o' t' supplied clay in t' nose cone. Avast! I'm nay sure this helped t' stability as it was intended.

Overall Rating: 3 out o' 5

Other:
T' win' jigs supplied in t' kit look flimsy and usin' them is "fiddley" but they do work. Ya scallywag! Aye aye! We will need t' do a center o' pressure study on t' model t' see if we can improve t' stability durin' boost. Ya scallywag! We might experiment with removin' some o' t' nose clay.