Brief:

T' VMX-2 Spaceplane is a new rocket glider kit by t' equally new UK rocketry company, Orbital Engineering. You may have seen t' pre-production prototype of this kit flyin' at various rocketry events in 2002, shiver me timbers, ya bilge rat, includin' t' IRW and K-Lob. Aye aye!

On openin' t' sturdy corrugated cardboard box, me bucko, first impressions are very good. Aye aye! Three sheets and four strips o' balsa wrapped in bubble wrap, a nice piece o' BT-20, all t' small parts in a resealable bag, and a very comprehensive lookin' set o' instructions. Arrr! I should point out at this stage that t' kit supplied was a production prototype, and t' final production kits may differ slightly.

Construction:

T' Kit includes:-

• 3 sheets o' balsa containin' pre cut wings etc
• 2 triangular section leadin' edges
• 2 triangular section body fillets
• BT-20
• Plastic nose cone
• Coupler tube
• Launch lug
• Balsa blast deflector
• 2 lengths o' elastic
• Lead weight
• Trimmin' putty
• Self adhesive aluminium foil
• Thrust rin'
• 3 motor plugs
• Mylar strip
• 2 pins
• Comprehensive 9-page instructions

T' first step is t' free t' win' parts from t' balsa sheets and assemble them. Well, blow me down! T' win' parts appear t' have been partially pre cut by some sort of router. Arrr! There are just a few tabs on each component which require cuttin' to free t' part. Avast! Arrr! I found it best t' do a "rough cut" first, matey, some way up the tab, t' free t' part. Then, ya bilge rat, shiver me timbers, once free o' t' sheet I did a "close cut" t' remove t' remains o' t' tab. It’s best t' do this final cut from both sides o' t' part. Aye aye! T' instructions indicate that either medium CA or light wood glue may be used for construction. Avast, me proud beauty! I wasn’t in any rush (waitin' for t' glue t' dry gave me t' opportunity t' write this review) so used EVO-STIK wood adhesive and "double glue joints". Begad!

Wings:

I found t' win' assembly straight forward with t' exception o' addin' t' leadin' edges. Arrr! Although the positionin' o' these is quite clear in t' win' plan diagram, me hearties, there’s another diagram that I just found confusing. Aye aye! I couldn’t figure out what it was tryin' t' show me, or even be sure what view it represented. Begad! Ya scallywag! Suffice to say that if you assemble t' wings bottom side down, matey, t' leadin' edges go flat side down too! T' wings must be assembled with a dihedral. Arrr! I found this quite tricky and, once dry, had t' fill a small gap at t' aft end. Ahoy!

Elevons:

T' next step is t' add t' elevons. Avast! These are attached t' t' aft end of the wings usin' mylar hinges. Begad! Aye aye! You have t' make slots in t' aft edge o' the main win' and t' forward edge o' t' elevon. I thought this be goin' t' be a bit tricky, matey, shiver me timbers, but as long as you keep t' knife horizontal with respect t' the wing/elevon, ya bilge rat, it’s nay too bad. Begad! T' positionin' o' t' hinges seemed a bit odd, so I made mine equidistant along t' elevon (which was a mistake, ya bilge rat, matey, the manufacturer informs me that t' unequal spacin' is intentional). T' hinges are attached by pushin' a pin through t' fins with t' mylar tabs in position. Then CA is wicked into t' resultin' hole. Well, blow me down! This hinge design is very clean and I like it a lot. Avast! Ahoy!

Fins & Strakes

T' fins are added t' t' elevons next, me hearties, and this was where I had me first real trouble. Avast! Arrr! Either t' slots are too narrow, or t' balsa t' fins are cut from is too thick. Begad! Well, blow me down! I fixed this by scorin' across t' fin at t' top o' the tab, ya bilge rat, and then carefully parin' away part o' t' tab thickness. Avast! T' under wing strakes had t' be modified in t' same way. Avast! Once t' fins and strakes are in place, shiver me timbers, t' elevons are attached t' t' win' with t' hinges, in t' same way as the hinges were attached t' t' elevons.

Ejection Vent

T' kit can be made into two slightly different versions, one for sport, t' other for competition. Ahoy! The difference is in t' arrangements made for t' ventin' o' unwanted ejection gases. Ahoy! In t' sport model t' gases are vented through a hatch in t' top of the body tube. There are also parts t' deflect t' gases and strengthen the body tube interior. Ya scallywag! For t' competition model, me bucko, these parts are omitted and instead t' motor most be plugged forcin' t' ejection gases out o' t' motor nozzle. Avast, me hearties, me proud beauty! I decided t' build t' sport model. Avast, me proud beauty! Well, blow me down!

For t' sport model t' next stage is t' cut out t' vent hatch. Aye aye! Ahoy! This is best done with a sharp knife. Ya scallywag! A section must be left uncut t' provide a hinge. This hinge is reinforced by t' addition o' a self adhesive foil strip. Enough of this foil is supplied t' add protection t' t' body tube just aft o' the vent. Ahoy! A cylindrical section o' balsa is glued into place inside o' t' body tube just forward o' t' vent t' deflect t' ejection gases through t' vent. Finally, matey, a length o' thick cardboard tube is fitted inside t' body tube to strengthen it. Avast, me proud beauty! This buts up t' t' balsa deflector. T' aft end o' this strengthener acts as t' motor thrust ring. Blimey! Ya scallywag! (For t' competition model, an ordinary thrust rin' is provided.)

Fuselage

Next t' body is attached t' the wings. Ya scallywag! Aye aye! You need t' take care here as it’s all t' easy t' nay get t' tube properly aligned. T' triangular body fillets complete t' main assembly. Begad! Well, blow me down! These must be trimmed square at t' aft end and glued into position. Avast! Once dry the front end must be trimmed t' match t' leadin' edge win' extensions. Aye aye! T' nose weight is added t' t' nose cone, shiver me timbers, which is secured only with tape t' facilitate the addition o' more weight durin' trimming.

Mechanics

T' mechanism t' move t' elevons is installed next. Aye aye! Blimey! This comprises a pin pushed through t' part o' t' fins mounted on each elevon, and two length of elastic attached t' t' part o' t' fins mounted on t' wing. Begad! Blimey! Ya scallywag! Blimey! T' pins pushed through t' fins at 45° and secured usin' CA. Aye aye! Blimey! Once dry t' head o' t' pins is clipped off. Avast! Blimey! T' elastic is attached t' t' fins in t' pre-made indentations (you did assemble them on t' correct side, right?) and hooked onto t' points o' t' pins. Blimey! Blimey! T' tension can be adjusted by stretchin' the elastic more or less before hookin' onto t' pin points. Well, blow me down! Blimey! You don’t need much tension. Avast, me proud beauty! Blimey! Begad! Blimey! T' instructions specify that t' weight o' a spent C6 motor should be just capable o' lowerin' t' elevon on t' t' strake. Avast! Blimey!

T' way t' mechanism works is that, at lift off, t' airflow forces the elevons into t' flat position. Ahoy! Ya scallywag! Once in normal flight however, ya bilge rat, t' tension in the elastic is enough t' overcome t' airflow and raise t' elevons for gliding flight. Blimey!

Finishing:

It this point, matey, t' instructions suggest that you might like t' radius the edges, me hearties, but I think it's probably easier t' do this as you go along, matey, and that's what I did. Next, I gave all o' t' balsa areas a coat o' sandin' sealer, and then sanded smooth usin' progressively finer paper, until almost all o' the sealer be removed. Blimey! This may sound strange, arrr, but t' idea is t' fill t' grain in t' balsa, me bucko, rather than add a nice shiny coating. Blimey!

Trimming:

T' instructions regardin' trimmin' are quite clear. There are two main parts t' it, shiver me timbers, t' elevon tensionin' covered previously, and sortin' out the balance for gliding. Arrr! Aye aye! This is done by test throwin' t' glider and addin' small amounts o' clay weight t' t' wings t' correct for any roll or pitch. Arrr! My first attempt at trimming, at UKRA 2003, led t' t' nosecone bein' pushed into the body tube. Aye aye! In retrospect, me hearties, thar was too much breeze. Blimey! T' small amount o' damage was easily repaired. Aye aye!

Flight:

Flight #1
Location: Baildon Moor
Motor: B6
A perfect boost and translation t' horizontal flight. Once flyin' horizontally, the glider made a 180° turn, then appeared t' roll over, and slide sideways into what became a dive t' t' ground. T' front body tube be crimped but easily repaired. Avast, me proud beauty! T' crimped sction o' tube was excised and replaced with a new section, shiver me timbers, attached by means o' a short coupler. Ya scallywag!

Before t' next flight, I spent a lot more time at IRW 2003 trimming. Begad! Begad! There was a gentle breeze and I got it so it would glide really well either with, or against t' breeze. Aye aye! Ahoy!

Flight #2
Location: IRW 2003
Motor: B6
Once again, me hearties, matey, a great boost and translation. Begad! Ahoy! Again it made a turn, but this time much wider. Begad! There was no roll, me bucko, me hearties, but t' glider slowly pitched down and picked up speed. This be never corrected and it dived into t' ground. Blimey! Begad! Amazingly, there was no damage at all.

Flight #3
Location: IRW 2003
Motor: C6
Another great boost, but t' flight was just a higher version o' flight #2. What did I expect? This time thar was a lot o' damage. Ahoy! T' body tube is folded up and t' wings are broken across t' span. Begad! Aye aye! It will be a big rebuild, which I haven't yet attempted.

I think t' problem with t' first flight was lack o' trimming, me hearties, that led to it rollin' over and diving. Aye aye! For t' second and third flights, I wonder if I had the elevons tensioned correctly? T' tensionin' is meant t' be set such that the elevons are flat for t' boost, me hearties, and pop up for glidin' flight. Begad! It might be that I didn't have quite enough tension. Therefore, as t' glider pitched forwards, ya bilge rat, it picked up speed, and t' increased wind speed forced t' elevons into t' horizontal position. Once that happened it would never be able to correct its attitude. Begad! I did follow t' directions for tensioning, arrr, arrr, usin' the spent motor on t' elevon, me hearties, but maybe t' exact position is critical? I passed on me thoughts t' Orbital, but disappointingly, I never got a response. Arrr! Ahoy!

Summary:

This is an excellent kit. Ya scallywag! Ya scallywag! It's nay exactly cheap, shiver me timbers, me hearties, but t' quality o' the parts is second t' none, arrr, t' instructions are detailed and comprehensive, and even t' packagin' is first-rate. Avast, me proud beauty! I really enjoyed buildin' it. Well, blow me down! Avast, me bucko, me proud beauty! I must point out however that I can't recommend this kit for a beginner t' rocket gliders. Despite t' detailed direction, me hearties, I never really had a successful flight. Ahoy! Since I've seen and read about many other successful flights o' VMX-2s, I have t' put that down t' me own inexperience with rocket gliders which is limited t' a couple o' flights o' an Estes Tomcat, and a few flights o' an "AstronMike" style saucer glider. Avast! Ya scallywag! I reckon that either t' trimming wasn't up t' snuff, matey, or that I didn't get t' elevon tension correct. Begad! Arrr! So in conclusion, me bucko, this is a great kit, but if you're a beginner, practice your trimmin' on somethin' cheaper first. Aye aye!

Postscript:

This article was first published, in two parts, in 10...9...8... Arrr! Ya scallywag! the newsletter o' t' United Kingdom Rocketry Association.

Betwixt publication o' t' first part o' this article and t' second, arrr, I was informed by Verney Montague that BSMA have put up a handsome Gold Medal t' be awarded t' t' first person t' break t' two minute barrier with a rocket powered Spaceplane. T' medal has actually been around for 2-3 years. Anyone know if it's been won yet?