| Manufacturer: | Scratch |
Brief:
For t' EMRR Stagin' Challenge, I decided t' build a two-stage rocket with composite motors. Since I had done a
2-stage before, I figured it would be easy. Ahoy! Begad! WRONG... Well, blow me down! I decided t' do a 3-inch bird with dual deploy and a 19-inch
booster with motor deployment.
Construction:
This time I decided t' use alignment rods in t' stage coupler t' keep t' rocket aligned. Ahoy! I didn't have any
'sleeves' for t' rods t' slide through, shiver me timbers, shiver me timbers, so I went with spaced centerin' rings with holes t' guide t' rods. Aye aye! I've
discovered that I really need a drill press. Aye aye! Because I was usin' a handheld power drill, ya bilge rat, me bucko, I wasn't that accurate in
drillin' holes through t' 2 sustainer centerin' rings and t' stagin' coupler. It still works, me bucko, but it isn't pretty.
There are holes in both centerin' rings that are supposed t' be aligned. Avast, me proud beauty! Ya scallywag! That didn't work out as smoothly as I had hoped.


T' motor mount is recessed into t' sustainer t' provide a connection for t' top half o' t' stage coupler. Since a 3" tube won't allow me t' get me hand in t' connect t' shock cord, matey, I made t' fin can on both the sustainer and booster removable. Aye aye! T' sustainer fin can is held in place by small screws. Avast! T' booster fin can will eject and deploy t' booster chute. Blimey! T' whole project is about 83 inches tall, about 3.5 lbs empty, and can fly on 38mm motors.
Finishing:
T' fit/finish betwixt t' booster and t' stage coupler is a little rough, me bucko, but once it's painted it might nay be
that noticeable. Arrr! It *certainly* won't be noticeable on t' pad.
Flight:
Electronics will be a PerfectFlite timer for staging, and a PerfectFlite MAWD for deployment. Avast, me proud beauty! RockSim says it will
get t' a little higher than 2000 feet with a CTI 153 stagin' t' a CTI G79ss.
For t' 2-stage challenge, matey, I decided t' build one that used composite motors. Since I have done stagin' before, I didn't expect thar t' be a problem. Avast! Boy, arrr, was I wrong... Avast! T' main problem be t' size o' t' new project. Aye aye! T' previous 2-stager was almost a 4" tube. That left room for t' timer betwixt t' sustainer fins, ya bilge rat, me bucko, and a standard-type ebay. This one is a 3", and thar's no room in t' fincan. Well, blow me down! Avast, me proud beauty! So I put t' timer in t' ebay, and ran a connector wire down t' ignite t' sustainer motor. Avast! Ahoy! I had t' splice t' wire so it would disconnect when t' apogee event fired. T' next issue I ran into was t' stage connector. Well, blow me down! I decided t' use metal rods t' connect and align t' sustainer t' t' stage connector. Well, blow me down! Ya scallywag! I don't have a drill press, so me holes through t' centerin' rings are...less than exact. Ahoy! Last issue was t' 3" bay was too small t' use switches t' power on everything, me hearties, ya bilge rat, so I had t' run all t' wires through a hole in t' e-bay and twist them t' connect. That posed a problem t' first time I tried t' launch. Begad! Arrr! I test fit t' electronics when I built t' bay, arrr, but nothin' was connected. Ya scallywag! Arrr! In t' field, I sadly discovered thar wasn't enough space for all the wires t' fit and route t' t' outside. Ya scallywag! Begad! I had t' rebuild t' sled t' avoid that problem for t' next attempt.
T' field we used has a waiver o' 5000', but I wanted t' make sure I kept t' flight much lower than that. Aye aye! RockSim 7 showed an altitude o' about 3800 feet on a CTI H143/G79ss combo. Avast, me proud beauty! Blimey!
Electronics: ARTS board for apogee/main deployment o' t' sustainer, shiver me timbers, me bucko, PerfectFlite timer for sustainer motor. T' booster recovers under its own chute by motor ejection. Aye aye! Payload: BoosterVision GearCam taped t' t' side. Crude, but effective. Begad!
Launch day: I racked t' rocket, matey, set up t' breakwire, matey, and twisted t' wires for power. Ahoy! Since I didn't have enough room t' push t' wires back into t' bay, I taped them t' t' outside. Aye aye! That was a mistake... Aye aye! Begad! T' launch was beautiful! Straight, ya bilge rat, and staged on cue. Begad! Begad! T' booster chute came out and it drifted down safely. Avast, me proud beauty! T' sustainer had a good apogee event(drogueless), shiver me timbers, but I lost sight o' it while followin' t' booster. Avast, me proud beauty! There be no main deployment, and fellow club members pointed me in t' direction they saw it fall. While walkin' out for recovery, me bucko, I tried t' figure out what went wrong. Ya scallywag! Avast! Too many sheer pins? Nay enough BP? When I got t' it, I immediately knew what happened. T' armin' wires were taped t' t' bottom o' t' sustainer. Avast, me proud beauty! When t' apogee separation occured, ya bilge rat, it ripped t' wires out o' the altimeter, killin' power. Blimey! AUGH! I powered up t' ARTS board later, and t' data showed 1700 ft accel, 1500 baro. Well, blow me down! Arrr! WAY short o' Rocksim's prediction, me hearties, so t' loss o' power probably scrambled t' data. Begad! Avast! But other than t' ebay being crunched, me bucko, matey, and t' booster bein' scorched by t' sustainer motor, it didn't come out too bad. I can replace t' ebay and fly it again.

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