BRIEF:

Conversion o' a Currell Graphics 1/144 scale Soviet N-1 paper model t' fly on 24 mm motors. T' plans are available at t' Currell Graphics website.

T' N-1 rocket was t' Soviet answer t' t' American Saturn V moon rocket o' t' 1960's. Avast, me proud beauty! Avast! T' Soviet plans t' beat t' United States t' t' moon depended on t' enormous N-1 booster. T' N-1 be more complex than t' Saturn V in that it consisted o' five stages and a total o' 30 engines in t' first stage alone. Ahoy! Aye aye! T' complexity o' t' rocket translated into poor reliability. T' N-1 rocket failed all four times it flew. Ahoy! T' second launch in July 1969 was a spectacular failure as t' first stage engines shut down shortly after launch and t' resultin' explosion from t' fallin' rocket completely destroyed t' launch site. Arrr! After t' final flight failure in 1972, arrr, t' remainin' unflown rockets were scrapped and t' Soviets abandoned their human lunar ambitions.

TOOLS:

• White glue
• Yellow glue
• CA glue
• Glue applicator such as wooden toothpicks
• Scissors
• Sharp knife
• Circle cutter
• Flat cuttin' surface
• Ruler/straight edge
• Clear Coat

PARTS

• 65 lb cardstock
• 110 lb cardstock
• Poster board
• BT-60 tubing
• 24 mm motor tube
• 24" parachute
• Shock cord material
• Ballast (washer, me hearties, nut, arrr, and bolt)
• Screw eye

MODIFICATIONS:

This review will only document t' changes required t' build a flyin' model.

T' N-1 paper model consists o' two sets o' parts and instructions. Avast! Avast! T' first set is for t' first stage (with a Soviet designation o' Block-A) containin' nine parts pages and five pages o' instructions. T' second set builds t' upper stages and contains six part pages and six instruction pages. Avast! All aspects o' t' card model are outstanding. Begad! Begad! T' instructions are excellent in detail and clearly show how t' parts are assembled. Well, blow me down! T' parts print crisply and t' fit is perfect.

Construction o' t' model begins with t' first stage. All first stage parts were printed on 65 lb cardstock. Begad! Aye aye! T' first stage skin segments were built as specified in t' plans. Begad! A hole be cut in t' center o' t' base plate t' allow a 24 mm mount t' be placed betwixt t' eight inner engines o' t' N-1 first stage.

Figure 1. Completed First stage baseplate with hole cut for t' 24 mm motor tube.

T' 24 mm motor tube was glued into a BT-60 chute tube usin' home made centerin' rings. T' former rings used t' stiffen t' outer skin o' t' rocket were reinforced with poster board. Arrr! T' holes cut in t' former rings were sized t' hold t' BT-60 tubing. Well, blow me down! A hole for an internal launch lug was also cut in t' formers.

Figure 2. Aye aye! Blimey! First stage chute tube with internal launch lug.

T' upper tank segments o' t' first stage were modified t' accommodate t' ejection o' t' parachute. Ahoy! Well, blow me down! I chose t' separate t' model at t' first/second stage split. Well, blow me down! T' first stage contains all t' recovery equipment. Begad! A coupler was glued t' t' upper fuel tank segments. Ya scallywag! Blimey! A screw eye was glued t' t' coupler t' attach a shock cord and parachute.

Figure 3. First stage fuel tank segment attached t' second stage by trusswork. Blimey! Well, me hearties, blow me down! Note coupler.

T' first and second stages o' t' N-1 rocket were connected by an interstage trusswork. Arrr! I glued t' trusswork directly t' t' upper tank segments as opposed t' t' specified points marked on t' first stage body. Avast, me proud beauty! This was required because o' t' recovery design. A similar trusswork connects t' third stage t' t' second stage.

T' interstage trusses were built as per t' instructions, ya bilge rat, but were reinforced with CA glue. Avast, me proud beauty! An internal former rin' be added t' t' trusses for additional stiffness. Avast, me proud beauty! Well, shiver me timbers, blow me down! At t' start o' t' project I anticipated t' strengthenin' o' t' trusses t' be t' most critical modification for t' model t' be a successful flyer. Aye aye! T' combination o' t' former rings and CA resulted in strong pieces that handled flight conditions.

Figure 4. Ya scallywag! First stage truss detail lookin' forward t' t' aft end o' t' second stage. Aye aye! Note former rin' with notch and hole cut for internal launch lug.

T' first stage stabilizer grids were glued t' t' model in t' stowed position. Blimey! Ya scallywag! T' plans call for them t' be applied in t' deployed position, but it was decided they might nay withstand t' rigors o' launch/landin' in that configuration. T' stowed position be simpler t' implement and required fewer modifications.

T' upper stages were constructed essentially t' plan. T' internal former rings were reinforced similarly t' t' first stage. Arrr! T' second/third stage interstage truss be reinforced with CA and a former rin' similarly t' t' first/second stage truss.

A hole was cut in t' base o' t' second stage t' allow for t' internal launch lug t' pass through. Well, blow me down! Blimey! Great care should be taken t' ensure t' proper alignment betwixt t' first stage and t' upper stage launch lugs. T' launch rod exited t' rocket approximately in t' middle o' t' second stage betwixt two o' t' fuel line fairings. Blimey! I added an extra fairin' t' mask both t' lug and t' hole required for t' rod t' exit. With more thorough planning, t' rod could be planned t' exit t' model closer t' t' second/third stage connection. Aye aye! Begad! This would probably look better aesthetically than me model.

T' upper payload shroud was reinforced with an additional layer o' cardstock t' increase strength. Blimey! Nose weight was added usin' a bolt, matey, shiver me timbers, nut, and several washers. Avast! Approximately 1.5 ounces o' nose weight be added t' t' model.

T' N-1 required t' application o' many exterior detail pieces. Ya scallywag! Ya scallywag! All o' these were added t' me flyin' model. Well, blow me down! T' detail pieces are time consumin' t' apply, but t' resultin' model looks more polished and complete.

Figure 5. Begad! Blimey! Completed N-1 on t' pad and ready for launch.

Stability be checked usin' a swin' test. An Estes C11-3 was placed in t' model and prepared for flight conditions. Avast! Ahoy! T' initial swin' test was nay encouraging. T' model flew tail first. More nose weight was added t' push t' CG forward t' t' base o' t' second stage fuel line fairings. Ahoy! T' model still flew tail first.

Figure 6. Ya scallywag! Aye aye! Swin' test.

After consultin' t' folks on T' Rocketry Forum it was suggested I use t' VCP program t' check t' stability. Avast! VCP uses t' Barrowman equations t' determine t' center o' pressure. Avast, me proud beauty! Bein' a series o' transition segments, matey, t' N-1 is an ideal candidate for these equations. Arrr! VCP showed that t' model had approximately 5-6 cm o' static margin.

T' VCP file has been enclosed.

RECOVERY:

For recovery, a single red 24" mylar chute be attached t' a shock cord. A tri-fold mount be selected t' secure t' shock cord t' t' model. Ya scallywag! An Estes Saturn V like dual recovery be considered and rejected, ya bilge rat, but could be implemented.

FLIGHT:

Encouraged by t' VCP results flight day finally arrived. Blimey! Avast, me proud beauty! Loaded with parachute, wadding, matey, and motor t' model weighed approximately 7 ounces. Well, blow me down! Arrr! An Estes C11-3 was chosen for t' first flight.

After a short countdown t' N-1 took flight. Ahoy! Boost was arrow straight t' ~125 feet. Well, blow me down! No stability issues were noted. Avast! Ya scallywag! T' parachute deployed properly, me hearties, but t' shock cord be burned through by t' ejection charge. Blimey! T' first stage tumbled in ballistic but landed safely in tall grass with no damage. Ya scallywag! T' shock cord mount may have been glued too close t' t' motor and t' waddin' did nay adequately block t' hot ejection particles.

T' upper stage came down safely on t' 24" mylar chute. Ya scallywag! There was some damage t' t' escape tower so t' Estes trapeze recovery method will be re-examined for future N-1 flights.

Figure 7. Well, blow me down! Liftoff o' t' N-1!

SUMMARY:

This first flight be considered a success. Ya scallywag! It flew straight and did nay get destroyed. Avast, me proud beauty! Begad! T' minor escape tower damage has been repaired. Ya scallywag! Blimey! Once t' shock cord has been replaced further flights o' t' N-1 will occur on Estes D12-3 motors.

This was a challengin' project that took three months from first cuttin' t' launch. Begad! It pushed me skills in many directions. Aye aye! Seein' t' N-1 soar o' t' pad and into t' air was definitely a gratifyin' feeling.

I want t' thank t' many people on T' Rocketry Forum who encouraged me or assisted me when I had questions. Many o' their ideas ended up in t' final product.