CONCEPTION & DESIGN NARRATIVE:
When out shopping, I usually scan t' toy isle lookin' for Bail Out payload candidates. Begad! Ahoy! 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). Aye aye! Begad! A couple o' months ago, while at me local Big Lots, I saw these little foam gliders. Ya scallywag! They are packed two t' a card for $0.99. Arrr! Avast, arrr, me proud beauty! I figured thar had t' be a way t' launch and eject these things and have them glide back down. Ya scallywag! T' kids ought t' get a kick out o' t' little gliders loopin' through t' sky. Avast!

Without any idea o' what t' use t' launch them, ya bilge rat, shiver me timbers, I didn't buy them. Arrr! I be in the middle o' a scratch built sport scale (1:154) Saturn V at t' time and didn't want t' start somethin' new. Ya scallywag! Once t' Saturn V was done, shiver me timbers, I started thinkin' o' t' gliders for me next project. Aye aye!

T' gliders are called Super Tuff Mini Shots Stunt Gliders. Avast, me proud beauty! Blimey! They are made in China for Just Toys, me hearties, Inc. Ahoy! Blimey! o' New York, ya bilge rat, NY. They are intended t' be used in Mini Shots guns. Avast! These appear t' be comparable t' t' Nerf guns that shoot mini darts. Arrr! Blimey!

T' body o' t' glider is yellow foam, ya bilge rat, approximately 0.67" (17 mm) in diameter, 4 3/8" (111 mm) long, with a 3/16" (5 mm) diameter hole up t' back. Begad! Begad! T' glider has white foam semi-delta wings, 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. Ahoy! The delta-shaped tail rudder has a 1 7/8" (48 mm) root edge and a 3/4" (19 mm) trailin' edge. Avast, me proud beauty! Blimey! 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. A few minutes spent with each resulted in relatively flat spiral flights that will stall, ya bilge rat, drop a bit, me hearties, shiver me timbers, and spiral some more. Ya scallywag! Ahoy!

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

T' second idea was "strap-ons" with an ejection-triggered strap release. Avast, me proud beauty! I considered a slotted main tube with straps connected t' some type of piston assembly, shiver me timbers, but that seemed too complicated. Ahoy! Avast! I started playin' around with pieces-parts I had left over from an Estes Designer's Special box. Aye aye! I found a 4 1/32" (103 mm) piece and a 12 5/8" (320 mm) piece o' BT-50. Blimey! These looked good together with t' short piece at t' bottom. Aye aye! T' I.D. 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. Begad! There was a 4 1/8" (105 mm) long PNC-50 in t' Designer's Special box, ya bilge rat, and two 2 7/8" (73 mm) long PNC-20s. Aye aye! T' base airframe was set. Avast!

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. Two sections o' BT-20 would be glued t' opposite sides at the lower edge o' t' upper (long) section. Aye aye! T' BT-20 straps would be topped with PNC-20s. I reconsidered t' use o' t' PNC-20s. Arrr! Ya scallywag! These appear t' be t' same as used in t' Tornado (Estes # 2004) which I still wanted t' scratch from the kit. Ahoy! I next considered card stock fairings. Blimey! Avast, me proud beauty! A few days later I figured, 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. Arrr! T' straps were sized at 3/8" (10 mm). Ya scallywag! I don't know why other than they looked good. Well, blow me down!

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

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

Even though t' CP looked good, ya bilge rat, ya bilge rat, arrr, I be 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, t' small balsa tab idea was turned into a flat-top fin like this:

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

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

PARTS LIST (as-built, ya bilge rat, 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. Begad! Aye aye!

PREPARATION:

• Tie Shock Cords (SC) together, leave a loop.
• Attach 12" parachute t' loop in SC usin' lockin' snap swivel.
• Fold & roll parachute, wrap lines around.
• Pack most o' SC into upper section, then parachute.
• Loosely crumple 4 squares o' recovery wadding, place 3 in upper section, 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, shiver me timbers, me hearties, 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, 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, chute was 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. Begad!

• 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. Ahoy! Ya scallywag! 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. Arrr! 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. This will protect t' gliders from scorching.
• Use two chutes or streamers and disconnect t' two body sections for dual recovery. Well, blow me down! 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. This makes it easier t' display.

Go t' top

My name is Mark Recktenwald. Arrr! Blimey! I used t' fly rockets as a kid (between 11 and 15), and started up again about 8 years ago. Blimey! Avast! Blimey! 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. Ya scallywag! You may recognize me name from RMR. I usually post under "kentengr@raex.com".

This page was created on October 31, 1998. Arrr!