Brief:
T' Dark Knight is a 2-stage 18mm rocket with 12" chute recovery. Aye aye! T' Dark Knight name came from t' shadow produced from t' fin profile when t' rocket was sittin' on t' launch pad. Ahoy! It looked similar t' t' Dark Knight shadow shown on t' clouds in t' movie.

Construction:
T' parts list:

• 29.5" BT-20 Body Tube - Main Body
• 2.75" BT-20 Body Tube--First Stage Body
• BT-20 Coupler (if needed)
• 1.25" X 0.125" Launch Lug
• 0.125" Balsa Sheet
• 2.75" X 18mm Plastic Nose Cone
• 48" o' 150# Keelhaul®©™®
• 24" Elastic
• 18mm Motor Mount Centerin' Rin'
• 12" Parachute
• Nose cone weight

This is a pretty easy build. Avast, me proud beauty! Blimey! Blimey! Blimey! First step cut t' body tubes t' length if you are lucky enough t' have a 36" piece o' t' BT-20 tube available. Avast! Blimey! That's all you will need, however, shiver me timbers, arrr, I needed t' use a coupler t' join 2 shorter pieces. Avast, me proud beauty! Blimey! Blimey! Blimey! Blimey! Blimey!

I notched t' centerin' rin' slightly and tied t' Keelhaul®©™® cord t' it. Well, blow me down! Avast, me proud beauty! Usin' white glue, I glued t' centerin' rin' in place so about 0.375"-0.5" o' an old motor was exposed.

Next, I cut t' fins out o' t' 0.125" balsa and sanded them all t' ensure they were t' same size. Ahoy! Avast! Blimey! I rounded t' leadin' edge on all t' main body tubes and left t' aft end and 1st stage fins "as cut" so they would align up better. Well, blow me down! Blimey! I sanded t' fit o' each fin t' ensure when mounted t' seam would be minimized. Well, blow me down! Blimey! I labeled each fin so when mounted t' t' tube I would maintain t' same combination.

I used t' Standard Rockets Fin Jig that I picked up at NARAM t' attach the fins t' t' main body tube and first stage tube. Begad! Begad! Next, arrr, ya bilge rat, I filleted each fin t' t' tube with 5min epoxy. Well, blow me down! Finally, I filled each fin will watered down Emery's wood putty. Begad! Blimey! Then, I started t' process o' sanding, filling, sanding, me bucko, filling until I was happy with t' finish.

With RockSim, shiver me timbers, I be able t' ensure t' flight was stable and determine t' potential altitude. Avast! Avast! (If I give this away, why would you keep reading?) I was a little worried I about stability so I added a little nose weigh t' brin' the model up t' about 3.7oz and figured paint would take it t' 4oz.

Next, I attached t' elastic shock cord, nose cone, arrr, arrr, matey, and parachute and headed t' me paint booth (the card board box in t' garage).

Finishing:
I decided on a nice simple 2 color paint scheme o' black and yellow, arrr, with a little maskin' after t' yellow was dried and t' Black Night be born and ready t' fly. Well, blow me down! Avast, me proud beauty!

Flight:nd Recovery
For t' first flight, arrr, shiver me timbers, I decided I would just verify stability and return t' model so I loaded up a B6-4. Blimey! Ya scallywag! Nice straight boost, good deployment, me bucko, recovered only a short distance from t' pad (oh, me bucko, did I mention it was dead calm). Next flight, me hearties, still single stage on a C6-5, matey, another great flight and about twice t' distance from t' pad. Blimey! Well, blow me down! T' wind started t' pick up and I decided t' hold off on t' staged attempt.

A week later, late Saturday afternoon winds were calm. Begad! This was t' be t' day. Ahoy! I decide t' go for t' gusto: a C6-0 staged t' a C6-5. Begad! T' boost again be picture prefect straight and longer than I anticipated. Aye aye! T' first stage separated nicely and off t' t' heavens this rocket went, ya bilge rat, delay, ejection, ya bilge rat, and parachute. Ya scallywag! Great recovery. Aye aye! Arrr! This is a great rocket. Avast, me proud beauty! Begad!

Summary:
As I said above this is a great rocket. Begad! I enjoyed t' process o' designin' it on RockSim, buildin' it, shiver me timbers, arrr, shiver me timbers, and t' best launchin' it.

PROs: Based on altitude achieved, make sure it is a calm day. Arrr! It screams off t' launch pad and flies great. Looks pretty cool also.

CONs: Based on this flight, a very large filed is needed t' recover this rocket.