Brief:
This be t' Sport Scale SR-71 Blackbird Model Rocket. Avast, me proud beauty! Blimey! It is an 18mm motor with parachute recovery Estes challenge kit. Ahoy! 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. Arrr! I built kit number EST-7003. Arrr! Arrr! It is labeled as a "Challenge" kit series with a skill level three. Inside t' box you will find three body tubes, arrr, a plastic nose cone, arrr, two plastic tail/inlet cones and one die-crunched balsa sheet. Begad! Also included are two green centerin' rings, arrr, engine mount tube, arrr, engine hook, me bucko, one launch lug, die-cut paper patterns for t' win' and jigs, a parachute kit, some shock cord and a rectangle o' water slide decals. 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. There is even a decal placement chart. This kit be given t' me by a friend o' a friend so I don't know how old it is, ya bilge rat, 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. T' kit provides two cardstock "jigs" t' lay t' fins on while they are dryin' in order t' keep them aligned. Blimey! T' jigs are used again on t' outer fins t' keep them level with t' inner "wings". Avast! I used aliphatic resin ( carpenters yellow glue). Avast, me proud beauty! I put a bead o' glue on t' fin, let it sit for a minute t' thicken. Ahoy! 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". Ya scallywag! 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. Begad! T' fins came out pretty straight.

T' trick in this kit be t' center paper fuselage overlay. Well, blow me down! Arrr! There is a top and a separate bottom piece. T' paper is almost impossible t' line up exactly with t' balsa fins. Partly because o' t' poor quality o' t' die cuttin' on t' balsa. Ahoy! Blimey! You can use small black sprin' type paper clips t' hold t' paper around t' edge o' t' balsa fins. Ahoy! Glue t' paper in steps, as per t' instructions and take your time, me bucko, shiver me timbers, it actually works!

You could scratch build this kit. Blimey! You would just have t' cut out your own paper pattern for t' center fuselage piece. Aye aye! 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. Well, blow me down! Blimey! Avast, matey, me proud beauty! Blimey! T' top fins angle in and t' lower fins angle outward as per prototype. Begad! 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. Avast! Blimey! Perhaps they were just old. Avast! Blimey! 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, B6-4 and C6-5. Ya scallywag! Considerin' that t' box cover weight shown is 3.2 oz. Avast, me proud beauty! Ya scallywag! I don't know where they came up with this number, this thin' is heavy! Ours came in at 4.1+ . Arrr! Ahoy! T' instructions tell t' builder t' add ALL o' t' provided clay in t' nose cone. So I did t' very first launch with a C6 engine. As far as launching, shiver me timbers, t' model is very conventional and it does requrie recovery wadding. Blimey! T' motor retention is standard Estes wire clip.

T' Blackbird looks awsome when finished. Avast, me proud beauty! In addition it is a somewhat unusual rocket t' brin' out t' t' launch pad.

T' first flight was loaded with an Estes 18mm C6-3 and four sheets o' blue recovery wadding. Well, blow me down! Well, blow me down! 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. Blimey! 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. Ahoy! T' provided shock cord is way too short, me bucko, shiver me timbers, so we added 18 inches o' some after market shock cord. Well, blow me down! Avast, me proud beauty! It be gluded in via t' three fold card stock method, shiver me timbers, just like any other rocket kit. Aye aye! T' recovery parachute is good. Aye aye! 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. We taped t' motor casin' with some scotch tape t' make up for t' smaller diameter. Ahoy! With less power, me bucko, t' Blackbird flew straighter for some reason! This be a great flight with perfect ejection. 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, because you have t' wait for t' glue really t' dry on one operation in order t' proceed t' t' next step. T' die-cut balsa fins would be much better if they were laser cut. Blimey! As they were, it took some re-sanding, matey, fillin' and fittin' t' get them t' fit properly. Avast! T' plastic parts supplied look nice and fit perfectly.

I believe t' decals were just old, some o' them did nay stick well at all. Arrr! Overall t' rocket looks good, it was fun t' build. Well, arrr, blow me down! T' kit instructions directed t' builder t' put all o' t' supplied clay in t' nose cone. Begad! Begad! 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. We will need t' do a center o' pressure study on t' model t' see if we can improve t' stability durin' boost. We might experiment with removin' some o' t' nose clay.