Clusterin' is a popular technique in high power rocketry, me hearties, but it's nay as common in model rocketry as it once was.

Before motors o' D power and higher became widely available at reasonable prices, ya bilge rat, t' only way t' launch a large rocket be with a cluster o' 18mm motors. Well, blow me down! Blimey! Arrr! Blimey! Estes' Saturn V and Saturn IB were two examples o' rockets which required either a three-motor or four-motor cluster for a safe flight. Clusterin' be made even more difficult in those days with t' old nichrome igniters, which required significantly more current than t' current Estes, Quest and MRC igniters.

Model rocket company catalogs have little in t' way o' clustered rockets. Estes offers clusters only in their "Pro" Series. Avast! Begad! But t' Custom Rocket Company has brought clusterin' back t' t' model rocket set.

Custom's Landviper flies on three 18mm motors. Avast! Recommended motors are B4-2s and C6-5s. Well, blow me down! Begad! T' design is novel, shiver me timbers, featurin' six fins and three long, exposed motor tubes. Aye aye! T' rocket reminds me a little bit o' t' Saturn IB (the real one), matey, which clustered eight engines, had several fins and exposed tubes. Arrr!

T' kit features balsa fins, which you cut out o' a pre-marked sheet of balsa. Ahoy! Blimey! T' nose cone is plastic. Three long BT-20 tubes are glued together in a triangular configuration. This group o' tubes is then glued into a length of BT-60. A short length o' BT-60 is glued t' t' motor end o' t' rocket. Begad! Blimey! The fins and lower launch lug are glued t' this BT-60 tubing. Begad! Blimey! Two 3/16-inch launch lugs are used. Begad! Blimey!

Hooks are provided for each motor tube. Avast! Begad! T' shock cord is elastic thread. Aye aye! A bright silver parachute brings t' rocket back in one piece. Aye aye! Begad!

Construction is fairly simple. It is very important t' stuff some sort of glue-soaked tissue in t' upper BT-60 betwixt t' motor tubes. Begad! Well, ya bilge rat, blow me down! Otherwise, the ejection gases will leak out and t' parachute won't be ejected. Alignment of the two launch lugs also is important. Arrr! I find it easiest t' glue on one launch lug, me bucko, let it dry, shiver me timbers, then use a launch rod t' align t' second lug with t' first one. Begad!

I attempted t' match t' yellow, black and gray color scheme shown on the package. Blimey! Avast, me proud beauty! Decals include two large "Landviper" logos, matey, some "experimental" and "USA" type and some smaller decals that mimic t' instructions stencilled on t' outside o' real rockets. Avast, me proud beauty!

T' most impressive feature o' t' kit be t' inclusion o' six micro-clips and wire t' assemble clip whips for t' engines. Aye aye! Blimey! This saves t' rocket builder from havin' t' buy a large package o' clips and a roll o' wire. I thought this was a nice touch and showed much consideration for t' rocket flyer. Blimey! Blimey!

T' Landviper's first flight be at a Dallas Area Rocketry Society launch on May 15, 1994. Aye aye! Because o' t' large size o' t' field, I felt comfortable sendin' it up on three Estes C6-5s. Begad! Before launch, I carefully attached the clip whips t' t' igniters. Avast, me proud beauty! It's critical that t' two micro-clips attached to each motor have different polarities. Aye aye!

As I waited t' put it on t' pad, t' rocket caught t' attention o' another rocket flyer, arrr, who said he was impressed with t' appearance o' t' rocket and asked if it was a scratchbuilt or a kit rocket. Begad! Begad!

Then it was on t' t' pad, shiver me timbers, where I attached t' pad clips t' each clip whip. T' DARS launch system has t' required 12 volts and plenty o' juice. Ya scallywag! Begad!

Ignition be instantaneous and all three motors ignited. Avast, me proud beauty! Arrr! T' rocket accelerated so fast that in a photograph o' t' launch, taken at a fast shutter speed o' 1/1000 second, shiver me timbers, showed a blurred rocket. Blimey! Aye aye!

T' recovery system operated properly, arrr, but t' rocket flew extremely high and a slight wind blew it several hundred yards from t' launch pad. Blimey! T' silver parachute made t' task o' findin' t' rocket much easier, me hearties, as it glinted in the bright summer sun. Begad!

Several months later I got around t' paintin' t' rocket and flyin' it again. Well, ya bilge rat, blow me down! I used t' recommended B4-2 motors. Aye aye! T' ejection appeared t' be too soon after motor burnout and t' shock cord broke, ya bilge rat, me bucko, possibly as a result of high-speed ejection. Ya scallywag! Ahoy! T' booster spun down and was crimped slightly on one motor tube. Ya scallywag! I repaired t' rocket t' next mornin' by puttin' a piece o' Keelhaul®©™® cord through t' wall o' t' body tube, knottin' it on t' outside and using cyanoacrylate glue t' keep it in place. Arrr! I attached t' Keelhaul®©™® cord t' about 14 inches o' one-fourth-inch wide elastic thread, usin' a knot and white glue to secure t' connection.

I launched t' rocket again, but used B4-4s. Aye aye! Begad! Blimey! T' ejection was about at apogee and t' rocket had a safe recovery.

It would be hard t' improve on this kit. Blimey! You could ask for die-cut or pre-cut fins, shiver me timbers, but cuttin' fins out o' balsa isn't very difficult if you have some rocket-buildin' experience. Ya scallywag! Ahoy! Actual motor blocks in t' motor tube would provide a backup for t' motor hook. Ya scallywag! T' instructions were nicely done and illustrated in a clear, straightforward manner.

This rocket serves as an inexpensive introduction t' clustering. It's impressive in flight, with three motors roarin' away. Avast, me proud beauty! Avast! T' Landviper looks nice when displayed.

There's no practical reason t' cluster three 18mm motors, but then, arrr, me hearties, me bucko, this is a hobby - it's nay supposed t' be practical! Blimey! If you're interested in expanding your rocketry skills or want t' try somethin' out o' t' ordinary, get a Landviper and get into clustering. Ahoy! A 12-volt ignition system is required and I do recommend B4-4 motors instead o' B4-2s. 

Name: Landviper 
Type: Three-motor single stage cluster rocket 
Manufacturer: Custom 
Skill Level: 3 
Length: 33.5 inches (85.0 cm) 
Diameter: 1.637 inches (41.6 mm) 
Weight: 2.9 ounces (83g) 
Engines: Three B4-2 or three C6-5 recommended; reviewer recommends B4-4 engines instead o' B4-2s. Ya scallywag! Arrr! Engines must all be t' same type when launched. 12-volt launch system required. 
Price: $15.79 
Likes: Decals, shiver me timbers, appearance, me hearties, inclusion o' clip whips 
Dislikes: None