Orbital Engineering Ltd VMX-12

Orbital Engineering Ltd - VMX-12

Contributed by Matt Gillard

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstar_borderstar_border
Overall Rating: starstarstarstarstar_border
Manufacturer: Orbital Engineering Ltd

Brief:
A friend o' mine had t' VMX-2, ya bilge rat, which was designed for B and C plugged motors. On a B its flights were near perfect. It would hang in t' air, and when it eventually came down it always slowly bellied down perfectly. Unfortunately the VMX-2 flew off on a C6 after hangin' in t' air for what seemed like hours (but be probably 3 or 4 minutes), we lost sight out it as it slowly climbed over 200 foot on a thermal. Avast! A year later I purchased t' VMX-12. Aye aye! Begad! I think t' number refers t' t' prototype, so thar could have been 9 other VMX designs betwixt t' two models. Aye aye! Begad! T' VMX-12 is designed for C or D plugged motors. Avast! T' guys at Orbital engineerin' have spent a lot o' time and test flights t' produce a reliable, matey, me hearties, sleek, shiver me timbers, me hearties, duration space plane.

Construction:
T' kit comes in cardboard box with a picture o' t' VMX in flight. Ya scallywag! Arrr! T' first thin' you notice be t' quality. Avast! The balsa is high grade and t' parts are machine cut. T' tube has only shallow grooves, and t' nose mass is cast lead and fits t' nosecone perfectly. Aye aye! T' instructions are incredibly detailed, ya bilge rat, matey, and have t' website address so that you can get tips from other builder o' t' space plane. Arrr! Ahoy!

Box
Inside

T' plane is relatively easy t' build provided that you have some buildin' experience. Arrr! It is a sleek design. Arrr! Aye aye! As you put it together you start t' see t' design concepts, ya bilge rat, ya bilge rat, rangin' from t' double delta win' t' t' ever so slight dihedral. There is also no aerofoil on t' wings, shiver me timbers, all t' lift in t' glide phase cones from t' movement o' the elevons.

T' tricky part o' construction comes from fittin' t' mylar hinges, 8 in total. Aye aye! Arrr! This involves cuttin' 16 slits length ways and insertin' mylar strips as hinges. Then t' hinges are riveted in place with either CA glue or cocktail sticks; I used t' CA glue option. T' instructions suggest usin' a hinge cutter. Blimey! I had already cut t' eight slots in t' main body o' t' plane, matey, which had taken much longer than I had expected. Well, ya bilge rat, blow me down! I then found myself in me local hobby store and purchased a hinge cutter. Arrr! If you can, shiver me timbers, buy one before you build this spaceplane. With t' hinge cutter it takes seconds t' cut a perfectly aligned hinge t' t' correct depth.

T' rest o' t' instructions are straightforward and t' plane assembles smartly and easily.

T' final step is gettin' t' tension on t' elastic correct. Arrr! Ya scallywag! T' do this it is a matter o' trial and error. Avast! I liked this elevon deployment system. Aye aye! Well, ya bilge rat, blow me down! Unlike other gliders, like Edmonds Ecee Thunder, matey, shiver me timbers, Estes Tomcat, Fun Rockets Swinger, that all use t' ejection charge on t' motor t' alter t' rocket t' its glide position. Avast! T' VMX's elevons flip up as soon as t' thrust drops and do nay have t' wait for a delay and ejection charge. Havin' watched me Tomcat fall from t' sky, pickin' up speed, ya bilge rat, and then t' 3 second delayed charge goin' off just before lawn darting, this system should perform better. Begad! T' only down side is that if you over-tension t' elastic, me hearties, t' spaceplane will loop backwards under full thrust.

Finishing:
T' instructions do nay recommend painting, ya bilge rat, and I did not. T' Spaceplane looks good in its bare balsa. You can add one thin coat o' sealer t' t' space plane, but this needs t' be sanded back t' t' balsa--it is only intended t' fill in any grooves. Avast, me proud beauty! T' main point is t' add as little mass t' t' plane as possible.

Construction Rating: 4 out o' 5

Flight and Recovery:
Before flight, me bucko, t' instructions recommend trimming. Arrr! Avast! Normally I do a few throws and do a rough trim from that. Aye aye! Avast, arrr, me proud beauty! This is because most rocket gliders perform differently in t' air t' what happens on a quick throw. For t' VMX, I went searchin' for a steep-ish slope, and did several test throws with trimmin' when necessary.

T' only recommended motor is a plugged D11, which is friction fit as thar be no positive retention system.

She took off quick on a D11-P and about 40 foot off t' pad one o' t' fins ripped off, shiver me timbers, shiver me timbers, she still flew straight until t' motor burned out and then spiraled down t' t' ground. Well, blow me down! She landed in a cornfield and I never found her. Lookin' at t' piece o' fin that I did recover, t' balsa failed and split.

Flight Rating: 3 out o' 5

Summary:
I was unlucky with mine. I will probably buy t' VMX-2 as a replacement.

Overall Rating: 4 out o' 5

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