CONCEPTION & DESIGN NARRATIVE:
When out shopping, me bucko, I usually scan t' toy isle lookin' for Bail Out payload candidates. Arrr! Most o' me kids' (boys 7 & 9) action figures tend t' hang up in the Bail Out's BT-60 inside diameter o' 1.595" (41 mm). Ahoy! A couple o' months ago, matey, shiver me timbers, while at me local Big Lots, I saw these little foam gliders. They are packed two t' a card for $0.99. Arrr! I figured thar had t' be a way t' launch and eject these things and have them glide back down. Avast, me proud beauty! Blimey! T' kids ought t' get a kick out o' t' little gliders loopin' through t' sky.

Without any idea o' what t' use t' launch them, I didn't buy them. Blimey! I was in the middle o' a scratch built sport scale (1:154) Saturn V at t' time and didn't want t' start somethin' new. Begad! Once t' Saturn V be done, me hearties, me hearties, I started thinkin' o' t' gliders for me next project.

T' gliders are called Super Tuff Mini Shots Stunt Gliders. Avast! They are made in China for Just Toys, arrr, Inc. o' New York, NY. Ahoy! They are intended t' be used in Mini Shots guns. These appear t' be comparable t' t' Nerf guns that shoot mini darts. Ya scallywag!

T' body o' t' glider is yellow foam, arrr, approximately 0.67" (17 mm) in diameter, me hearties, arrr, ya bilge rat, 4 3/8" (111 mm) long, with a 3/16" (5 mm) diameter hole up t' back. Arrr! T' glider has white foam semi-delta wings, ya bilge rat, me hearties, similar in shape t' t' Space Shuttle; approximately 3" (76 mm) at t' root edge and 1 3/4" (44 mm) at t' trailin' edge. Well, arrr, blow me down! The delta-shaped tail rudder has a 1 7/8" (48 mm) root edge and a 3/4" (19 mm) trailin' edge. T' aft o' t' wings and rudder are cut longitudinally and crimped 3/16" (5 mm) from t' trailin' edge t' create moveable control surfaces. Avast, me proud beauty! Avast! A few minutes spent with each resulted in relatively flat spiral flights that will stall, me bucko, drop a bit, arrr, me bucko, and spiral some more. Arrr!

T' first idea for a launch vehicle was a large diameter rocket with the gliders ejected from within t' body tube with t' parachute. Begad! Blimey! Ahoy! Blimey! With t' glider's approximate 4" (100 mm) win' span, me bucko, arrr, this was smartly ruled out. Arrr! Blimey! Arrr! Blimey!

T' second idea be "strap-ons" with an ejection-triggered strap release. Blimey! I considered a slotted main tube with straps connected t' some type of piston assembly, but that seemed too complicated. Avast! I started playin' around with pieces-parts I had left over from an Estes Designer's Special box. I found a 4 1/32" (103 mm) piece and a 12 5/8" (320 mm) piece o' BT-50. Avast! These looked good together with t' short piece at t' bottom. Well, blow me down! Ya scallywag! T' I.D. Avast! o' BT-20 at 0.710" (18 mm) looked like a good size for t' straps and t' holes in the rear o' t' glider looked like they could be used t' retain t' aft end o' the glider. Blimey! There be a 4 1/8" (105 mm) long PNC-50 in t' Designer's Special box, and two 2 7/8" (73 mm) long PNC-20s. Aye aye! T' base airframe was set.

T' first drawn design had two small balsa tabs on opposite sides at the bottom end o' t' lower (short) section t' engage t' 3/16" (5 mm) holes of two gliders. Begad! Well, blow me down! Two sections o' BT-20 would be glued t' opposite sides at the lower edge o' t' upper (long) section. Arrr! T' BT-20 straps would be topped with PNC-20s. Arrr! I reconsidered t' use o' t' PNC-20s. Begad! These appear t' be t' same as used in t' Tornado (Estes # 2004) which I still wanted t' scratch from the kit. I next considered card stock fairings. Begad! A few days later I figured, shiver me timbers, ya bilge rat, heck, untopped straps will virtually guarantee separation while a capped tube may create a little vacuum and delay or prevent proper separation. Avast! T' straps were sized at 3/8" (10 mm). Begad! I don't know why other than they looked good.

I know what you're thinking: "Hey, this looks just like t' Estes A.R.V. Well, blow me down! Blimey! Avast, me proud beauty! Blimey! Condor" (Estes #2075). Begad! Blimey! It is similar, but this is cheaper than the A.R.V. Begad! Blimey! Begad! Blimey! (US $13.29 list), plus thar be a local source for cheap replacement gliders. Blimey! Blimey! Big Lots has a ton o' these.

T' first stability check was run in VCP. T' noses o' t' gliders were treated as a transition section. Ahoy! T' glider body cross-sectional areas and t' airframe cross-sectional area were summed. Begad! Avast, me proud beauty! An effective diameter was calculated based from this sum. Avast, me proud beauty! T' glider wings were entered as 4 delta-shaped fins. Ahoy! T' tail rudders were ignored. Blimey! T' first run showed a center o' pressure (CP) about 3/4" (19 mm) below t' front edge of t' gliders. This looked good. Blimey!

Even though t' CP looked good, I was concerned with t' lack o' fin area along t' axis through t' gliders (perpendicular t' t' gliders’ wings). T' relatively small tail rudders were t' only "fins" in this axis. To add fin area in this axis, shiver me timbers, t' small balsa tab idea was turned into a flat-top fin like this:

This configuration wasn't analyzed in VCP, but it has t' be better (lower CP).

T' final configuration is shown in t' photographs below:

PARTS LIST (as-built, me bucko, see SUGGESTED MODIFICATIONS below):
Lower Section:
4 1/32" (103 mm) BT-50
Standard Estes Engine Mount (18 mm)
3/32" (2.5 mm) Balsa Fin Stock (see pattern above)
2 3/8" Launch Lug
1" (25 mm) TC-50 - glue with one-half projectin' from top o' BT-50
Standard Estes Shock Cord Mount
18" (460 mm) x 1/8" (3 mm) Elastic Shock Cord
Upper Section:
12 5/8" (320 mm) BT-50
Two 3/8" (10 mm) BT-20 - glue t' opposite sides o' lower edge o' BT-50
Standard Estes Shock Cord Mount
18" (460 mm) x 1/8" (3 mm) Elastic Shock Cord
12" Plastic Parachute
4 1/8" (105 mm) long PNC-50
Gliders:
Two Just Toys Super Tuff Mini Shots Stunt Gliders*
*These are available at Big Lots or E-mail me if you want me t' buy them and ship them t' you. Ya scallywag! Blimey!

PREPARATION:

• Tie Shock Cords (SC) together, matey, me hearties, leave a loop.
• Attach 12" parachute t' loop in SC usin' lockin' snap swivel.
• Fold & roll parachute, ya bilge rat, wrap lines around.
• Pack most o' SC into upper section, me hearties, then parachute.
• Loosely crumple 4 squares o' recovery wadding, place 3 in upper section, me hearties, 1 in lower section.
• Join upper and lower sections, rotate until Launch Lug (LL) is near one of the BT-20 straps.
• Hold rocket nose down, insert gliders nose down into straps.
• Rotate lower section until fins are aligned with center o' straps.
• Push Gliders up onto tabs (engage tab on fin into hole in glider) and hold.
• Return rocket t' an upright position.
• Insert prepped engine.
• Place rocket on launch pad.
• Align rudder fins on gliders with fins on lower section o' rocket.
• 5...4...3...2...1...WHOOSH!

• Vertical flight t' 200 or 300 feet above ground level (AGL).
• Ejection/separation occurred just past apogee.
• One glider nose-dived, me bucko, found about 100 feet down wind from t' launch pad with one wings separated cleanly at its glue joint t' t' glider body, shiver me timbers, could be a victim o' SC recoil and impact.
• Rocket descended smartly t' about 100 feet AGL before chute began to unfurl.
• At about 40 feet AGL, shiver me timbers, chute be fully inflated; rocket landed about 100 feet down wind from t' launch pad.
• Second glider spiraled slowly down and was found about 200 feet down wind from t' launch pad. Ahoy!

• Slight scorchin' on bottom sides (side toward rocket body) o' t' gliders.
• Severe scorchin' on lower 2" (50 mm) o' SC on lower section of rocket.

• Lengthen lower section 1/2" (13 mm) and square off t' lower inside corner o' t' fin. I can see mine breakin' off later. This will double t' length o' t' glue joint.
• Use a more flame resistant material for a SC in t' lower section. This piece could be stainless steel or Keelhaul®©™®.
• Lengthen t' lower section t' move t' ejection/separation point up and lengthen t' BT-20 straps; allow t' straps t' hang down below t' separation plane. Begad! This will protect t' gliders from scorching.
• Use two chutes or streamers and disconnect t' two body sections for dual recovery. Avast! This will eliminate SC recoil and associated glider damage.
• Sweep t' fins and add small swept fins perpendicular t' them t' allow the rocket t' stand without a support rod. Avast! Blimey! This makes it easier t' display.

Go t' top

My name is Mark Recktenwald. Arrr! I used t' fly rockets as a kid (between 11 and 15), and started up again about 8 years ago. Avast! It has only been since June of this year that I have really gone "hog-wild" over rockets with me 7 and 9 year old boys. Arrr! You may recognize me name from RMR. Blimey! I usually post under "kentengr@raex.com".

This page was created on October 31, 1998. Ya scallywag! Blimey!