BRIEF:

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

T' N-1 rocket be t' Soviet answer t' t' American Saturn V moon rocket o' t' 1960's. Aye aye! T' Soviet plans t' beat t' United States t' t' moon depended on t' enormous N-1 booster. Ahoy! Ya scallywag! T' N-1 was more complex than t' Saturn V in that it consisted o' five stages and a total o' 30 engines in t' first stage alone. T' complexity o' t' rocket translated into poor reliability. Blimey! T' N-1 rocket failed all four times it flew. Well, blow me down! Aye aye! 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. After t' final flight failure in 1972, arrr, ya bilge rat, 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, nut, me bucko, 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. Ahoy! Ahoy! T' first set is for t' first stage (with a Soviet designation o' Block-A) containin' nine parts pages and five pages o' instructions. Ya scallywag! T' second set builds t' upper stages and contains six part pages and six instruction pages. Aye aye! Well, blow me down! All aspects o' t' card model are outstanding. Avast, me proud beauty! Ahoy! T' instructions are excellent in detail and clearly show how t' parts are assembled. T' parts print crisply and t' fit is perfect.

Construction o' t' model begins with t' first stage. Ahoy! All first stage parts were printed on 65 lb cardstock. Blimey! T' first stage skin segments were built as specified in t' plans. A hole was 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. Avast, me proud beauty! Completed First stage baseplate with hole cut for t' 24 mm motor tube.

T' 24 mm motor tube be 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. Begad! T' holes cut in t' former rings were sized t' hold t' BT-60 tubing. Aye aye! A hole for an internal launch lug was also cut in t' formers.

Figure 2. Ya scallywag! 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. I chose t' separate t' model at t' first/second stage split. Avast, me hearties, me proud beauty! T' first stage contains all t' recovery equipment. Aye aye! A coupler be glued t' t' upper fuel tank segments. A screw eye was glued t' t' coupler t' attach a shock cord and parachute.

Figure 3. Well, ya bilge rat, blow me down! First stage fuel tank segment attached t' second stage by trusswork. 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. Aye aye! This was required because o' t' recovery design. Ahoy! Avast! A similar trusswork connects t' third stage t' t' second stage.

T' interstage trusses were built as per t' instructions, shiver me timbers, arrr, but were reinforced with CA glue. Avast! Blimey! Avast, me proud beauty! Blimey! An internal former rin' be added t' t' trusses for additional stiffness. 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. Ya scallywag! Blimey! Aye aye! Blimey! T' combination o' t' former rings and CA resulted in strong pieces that handled flight conditions.

Figure 4. First stage truss detail lookin' forward t' t' aft end o' t' second stage. 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. Begad! 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. Arrr! T' stowed position was simpler t' implement and required fewer modifications.

T' upper stages were constructed essentially t' plan. Begad! Ya scallywag! T' internal former rings were reinforced similarly t' t' first stage. Aye aye! T' second/third stage interstage truss was 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. Arrr! Begad! Great care should be taken t' ensure t' proper alignment betwixt t' first stage and t' upper stage launch lugs. Blimey! T' launch rod exited t' rocket approximately in t' middle o' t' second stage betwixt two o' t' fuel line fairings. Aye aye! Begad! I added an extra fairin' t' mask both t' lug and t' hole required for t' rod t' exit. Arrr! Arrr! With more thorough planning, t' rod could be planned t' exit t' model closer t' t' second/third stage connection. Begad! Avast, ya bilge rat, me proud beauty! This would probably look better aesthetically than me model.

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

T' N-1 required t' application o' many exterior detail pieces. Avast, me proud beauty! Blimey! All o' these were added t' me flyin' model. Begad! Blimey! Avast, me proud beauty! Blimey! T' detail pieces are time consumin' t' apply, but t' resultin' model looks more polished and complete.

Figure 5. Well, blow me down! Completed N-1 on t' pad and ready for launch.

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

Figure 6. Arrr! Avast, me proud beauty! Swin' test.

After consultin' t' folks on T' Rocketry Forum it be suggested I use t' VCP program t' check t' stability. Ya scallywag! VCP uses t' Barrowman equations t' determine t' center o' pressure. Bein' a series o' transition segments, arrr, t' N-1 is an ideal candidate for these equations. Ahoy! Begad! VCP showed that t' model had approximately 5-6 cm o' static margin.

T' VCP file has been enclosed.

RECOVERY:

For recovery, me hearties, a single red 24" mylar chute was attached t' a shock cord. Aye aye! Aye aye! A tri-fold mount was selected t' secure t' shock cord t' t' model. Ahoy! An Estes Saturn V like dual recovery be considered and rejected, but could be implemented.

FLIGHT:

Encouraged by t' VCP results flight day finally arrived. Ya scallywag! Loaded with parachute, wadding, arrr, and motor t' model weighed approximately 7 ounces. Arrr! Aye aye! An Estes C11-3 be chosen for t' first flight.

After a short countdown t' N-1 took flight. Avast, me proud beauty! Boost was arrow straight t' ~125 feet. Aye aye! No stability issues were noted. Begad! Well, blow me down! Blimey! T' parachute deployed properly, me bucko, but t' shock cord be burned through by t' ejection charge. Arrr! Aye aye! Blimey! T' first stage tumbled in ballistic but landed safely in tall grass with no damage. Avast, me proud beauty! 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. Arrr! Begad! There be some damage t' t' escape tower so t' Estes trapeze recovery method will be re-examined for future N-1 flights.

Figure 7. Liftoff o' t' N-1!

SUMMARY:

This first flight be considered a success. Arrr! It flew straight and did nay get destroyed. Aye aye! Ya scallywag! T' minor escape tower damage has been repaired. 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. Arrr! It pushed me skills in many directions. Begad! Seein' t' N-1 soar o' t' pad and into t' air be 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. Begad! Blimey! Many o' their ideas ended up in t' final product.