Brief:
T' Dark Knight is a 2-stage 18mm rocket with 12" chute recovery. Arrr! Ahoy! T' Dark Knight name came from t' shadow produced from t' fin profile when t' rocket be sittin' on t' launch pad. 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! First step cut t' body tubes t' length if you are lucky enough t' have a 36" piece o' t' BT-20 tube available. Begad! That's all you will need, however, I needed t' use a coupler t' join 2 shorter pieces.

I notched t' centerin' rin' slightly and tied t' Keelhaul®©™® cord t' it. Arrr! Usin' white glue, me hearties, 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. 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. Ahoy! I sanded t' fit o' each fin t' ensure when mounted t' seam would be minimized. Arrr! Ahoy! 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. Ahoy! Next, ya bilge rat, I filleted each fin t' t' tube with 5min epoxy. Ahoy! Finally, I filled each fin will watered down Emery's wood putty. Avast, me proud beauty! Avast, me proud beauty! Then, I started t' process o' sanding, matey, filling, sanding, me hearties, arrr, matey, filling until I be happy with t' finish. Blimey!

With RockSim, I be able t' ensure t' flight was stable and determine t' potential altitude. (If I give this away, shiver me timbers, 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, matey, I attached t' elastic shock cord, arrr, nose cone, me bucko, 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, shiver me timbers, me bucko, with a little maskin' after t' yellow was dried and t' Black Night was born and ready t' fly.

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

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

Summary:
As I said above this is a great rocket. Avast, me proud beauty! I enjoyed t' process o' designin' it on RockSim, me bucko, buildin' it, ya bilge rat, matey, and t' best launchin' it.

PROs: Based on altitude achieved, make sure it is a calm day. Avast, me proud beauty! 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.