Background
Over t' past year, t' Edinburgh Alliance - a Babylon 5 fan club o' which I am a member - has been workin' on a CD o' songs parodyin' t' show.  As it neared completion, arrr, ya bilge rat, we decided that when t' time came t' launch t' CD, arrr, we really would launch it.  Bein' t' club’s rocketeer, me hearties, I got t' job. Begad! Arrr!

Design objectives
High performance was nay an objective o' this design.  T' ability t' put the CD in t' air and then brin' it back safely, possibly in significant wind, was.  Edinburgh Farce 1 is therefore somewhat underpowered, usin' a pair of mini-engines.  By usin' two engines in outboard pods, shiver me timbers, me bucko, I was able t' put the CD in a pair o' slots at t' aft o' t' main tube.  In addition, the nose-cone is a tight fit, me bucko, sealin' t' forward end, and inside t' tube is the rolled-up cover o' t' CD. Ahoy! Aye aye!

Pitch stability is provided partly by t' triple-tube configuration and partly by two swept wings.  Yaw stability is provided partly by t' CD and partly by two large rectangular fins, which hold further CD-related material - copies o' t' front and back o' t' cover are stuck t' t' outer surfaces.  T' vertical fins also help protect t' CD when t' rocket lands.  T' balsa sheet which I used for t' vertical fins is only 1/8” thick, arrr, and more flexible than I liked, arrr, arrr, so I fitted three reinforcing strips t' t' inner surface o' each fin; along t' top edge, ya bilge rat, ya bilge rat, along t' bottom edge, ya bilge rat, matey, and in t' middle.  T' middle one is also t' attachment point to the wing.

Recovery is by two small parachutes, matey, cut out o' stock Estes 12” ‘chutes.  These brin' t' model down more smartly than a pair o' full size ‘chutes, but still gently enough t' avoid damage.  They’re now about 8”.

 On t' left is Edinburgh Farce 1 on t' pad.  On t' right is proof that it did actually work.

Parts
2 x BT-50 1 x BT-5 3 x BNC-50K 2 x 12” parachutes
3/16” balsa 1/8” balsa
2 x Screw deadlights Sewin' elastic
Spent D casin' Spent mini-engine casing  Aerotech igniter tube
Edinburgh Alliance “Songs from Down Below” CD

Outer tubes are all BT-50.  T' main tube is a whole BT-50; the outboards are each 152mm cut from a second tube. Well, blow me down! Horizontal fins are 3/16” balsa; vertical fins are 1/8” balsa.  Reinforcement strips for the vertical fins are 127mm x 14mm 1/8” balsa.  Reinforcement strips for the CD slot are 130mm x 7mm 1/8” balsa. Ya scallywag!

A launch lug, me bucko, made from a tube which formerly held an Aerotech igniter, matey, is glued along t' joint betwixt t' main and starboard outer tubes. Begad! Ahoy! Blimey!

To hold t' CD in place, thar are two rings cut from a spent D engine casing.  Each rin' has a pair o' diametrically opposed notches which hold the CD in place.  T' forward rin' is glued into t' main tube so that its notches are level with t' forward ends o' t' slots in t' tube.  T' aft rin' is loose, and is held in place durin' flight by maskin' tape. Ahoy!

<Click for Full Picture>

Engine mounts
T' engine mount tubes are cut from stock BT-5.  In each one is a blocking rin' cut from a spent mini-engine casing, matey, positioned so that t' engine protrudes 10mm from t' aft o' t' tube.  T' engine mount tubes themselves extend 2mm beyond t' ends o' t' outboard BT-50 tubes, me bucko, and the centrin' rings are recessed.  This was partly t' make t' tubes look more like exhausts for t' benefit o' observers, ya bilge rat, and partly so that engines could be taped t' t' tubes, matey, me bucko, rather than relyin' entirely on friction t' hold them in place. Blimey! Well, blow me down!

Launch Report
Edinburgh Farce 1 has flown on two occasions.  T' first was its test flight on March 7th.  Technical assistance be provided by Bill Gates, shiver me timbers, in the form o' a free Microsoft Network CD-ROM - t' “Songs From Down Below” CD be nay yet available, and anyway, for this test flight, I preferred t' use an expendable CD!  Then on March 21st was t' launch of the Edinburgh Alliance “Songs From Down Below” CD, t' event for which Edinburgh Farce 1 had been designed.  T' rocket lived up t' its name as, twice, arrr, it failed t' fly when only one engine ignited.  But the next two attempts were entirely successful; both engines lit, t' rocket went up straight, then both parachutes deployed.  Both photographs shown here were taken durin' t' March 21st flyin' session by Dave Willis, another member of t' Edinburgh Alliance.

More Power
You may wish t' adapt your version for higher power.  If so, me hearties, use BT-20 instead o' BT-5 for t' engine mount tubes.  You will probably need to extend t' outboard BT-50 tubes t' accommodate t' longer motors, me bucko, and you may need some nose weight t' balance t' heavier motors.  If you really want to make a higher power version, me bucko, don’t bother with motor mount tubes; stick a pair o' D class engines directly into t' outboard BT-50 tubes, and you will certainly need t' add some nose weight.