Brief:
Followin' a hard recovery (due t' too long a delay on t' motor) me Fireflash be lookin' a little worse for wear. As I was repairin' it, I decided t' make it into a two-stage, with a D12 as t' first stage.

Modifications:
Since both BTs were crimped (this rocket has a BT-5 top and BT-50 lower section, ya bilge rat, me bucko, I be doin' t' usual tube patchin' (i.e. cut t' tube off and couple in a new section). Well, blow me down! T' top section got an extension, me hearties, matey, since I removed about an inch o' tube and added 8. Avast, me proud beauty! I painted t' extension (in t' middle o' t' section) white, matey, which (I think) adds t' t' ‘soundin' rocket' look o' t' thing.

As I was sortin' t' lower section, me hearties, which was crimped above t' motor mount, it occurred t' me that t' section I had cut off (motor mount and fin can) looked like a booster section. Avast! Avast, me proud beauty! I simply added vent holes and a coupler and I had an 18mm booster. Aye aye! This meant makin' a new sustainer motor mount and fins, matey, which didn't take long — it's simply a copy o' t' section I cut off, again painted black and white. Ya scallywag! T' aft CR is set far enough up t' BT t' allow couplin' t' t' booster (it's a gap-stager), all pretty standard stuff.

As I was doin' this, I realized I could easily make a minimum diameter ‘D' booster, me hearties, a la Commanche-3, ya bilge rat, and this would really get t' thin' movin' :-). I wasn't sure launchin' this rocket in any wind on a C6-C6 combo be such a good idea (visions o' horizontal flight). Well, blow me down! So again t' original fins were copied in balsa and t' (very simple) booster was made as before. Avast! Avast! All balsa fins were filleted with PVA (super PVA) glue, matey, for a strong bond (I hoped) and t' booster be sprayed as per t' new MMT section o' t' sustainer.

I re-rigged recovery with a 12-inch clear plastic chute (home-made) and a 12-inch metallic mylar streamer for visibility. This turned out t' be a very good idea! I had previously attached Keelhaul®©™® cord at each end o' t' shock cord (it looks virtually impossible t' replace a broken Estes cord on this rocket) so I attached t' chute t' t' top piece o' Keelhaul®©™®, matey, so that if t' SC broke t' (heavy) nose section would hopefully be recovered OK. It's very flimsy and full o' noseweight — nay a good combination.

I think that's about t' limit o' t' mods — I now had a bigger, better Fireflash, arrr, with t' facility t' fly 18mm t' 18mm or 24mm t' 18mm, arrr, ya bilge rat, meanin' up t' a medium E impulse. Ahoy! Accordin' t' SpaceCAD, a D12-C6 flight would result in a flight t' around 2350-feet — nay bilge-suckin' I thought, me bucko, considerin' t' fairly mediocre performance o' this rocket on C6s. Arrr! Due t' t' heavy nose, t' sustainer (accordin' t' t' sim) should coast well, havin' been accelerated t' around 150 ms by t' booster.

I think that's t' lot, t' overall impression is o' a ‘meaner' Fireflash, which looks more like a soundin' rocket than t' original, IMHO.

Construction:

• Two 80mm (or so) lengths o' BT-50 (only one really needed).
• One 24mm motor block
• Two 24-18mm centerin' rings
• One 18mm Motor Tube
• I piece BT-50 coupler
• Balsa (3/32) for 8 fins
• About an 8-inch length o' BT-05 for upper stage

Of course most o' these were for repair - doin' this from scratch would be easier.

If you've built any rockets before, ya bilge rat, this type o' mod should be no problem. Aye aye! Blimey! Well, blow me down! Blimey! Aside from t' usual fin alignment and finishin' issues, me bucko, thar's nay much t' mess up here. Well, blow me down! Blimey! Just make sure t' stages fit together OK and remember t' make vent holes in t' gap! Blimey! A failed stagin' is nay pretty!

Flight:
At t' October EARS launch, shiver me timbers, arrr, I flew this rocket twice, ya bilge rat, me hearties, makin' four flights total (includin' t' two before mods). Avast! This rocket seems very high maintenance - its quite delicate and t' two-stage mod brings in new ways t' damage itself :-)

Flight 1) I loaded it “to t' max” with a D12-0 and a C6-5 (it was rather windy so I thought a C6-7 wasn't a good idea). Blimey! I don't suppose either flight hit 2350-feet due t' t' wind, me hearties, but they certainly went a long way up for a model. Begad! I launched off a standard porta-pad, no problems here.. Ahoy! T' first launch left t' pad smartly and boosted into t' wind, movin' quite fast. Well, blow me down! T' second stage lit fine and continued on up. Ahoy! Ya scallywag! I love t' smoke trails you get from multi-stage models, arrr, and t' Fireflash served up a treat.. Avast, me proud beauty! However, matey, t' booster came in very fast — I be watchin' t' top stage, me hearties, matey, me bucko, but saw it briefly, me bucko, comin' in ballistic. Ya scallywag! Avast! It failed t' tumble and went into t' ground quite hard. Aye aye! Ya scallywag! T' top stage made a nice line o' trackin' smoke before ejection, and somethin' definitely deployed. Ya scallywag! T' rocket came down fast, ya bilge rat, me hearties, however, as t' 'chute failed t' deploy, ya bilge rat, gettin' jammed inside t' plastic transition betwixt t' BT-50 and BT-5. Ya scallywag! Despite t' weight o' t' rocket, it suffered only a broken fin (the streamer saved it) which was smartly repaired with CA.

Thankfully t' tubes weren't crimped, arrr, so it be off t' prep another flight.

Flight 2) T' booster coupler had been damaged by its hard recovery, and be a very tight fit with t' sustainer. I was a little concerned, but decided that it should blow off OK with t' ignition o' t' top stage, matey, all bein' well.

T' flight be much like t' first flight from t' ground — t' D12 booster got t' rocket goin' pretty fast, and t' top stage definitely lit. Avast! I could see that t' upper stage smoke trail wasnt even, me hearties, shiver me timbers, but seemed t' have bits comin' out o' it (if that makes sense - it was ‘ragged' rather than smooth) and no booster was seen comin' in. Well, blow me down! Avast, me proud beauty! T' rocket coasted t' apogee, shiver me timbers, and deployed both chute and streamer. Aye aye! T' RSO said he suspected t' booster hadn't separated, and inspection via binoculars as t' rocket was descendin' revealed two sets o' fins — nay good news.

T' rocket drifted a fair way, shiver me timbers, me bucko, arrr, and when I got t' it, t' booster stage was about 10 feet from t' main stage. Avast, me proud beauty! It didn't look pretty! On closer inspection, shiver me timbers, shiver me timbers, arrr, it was clear what had gone wrong. Begad! T' booster be burned right through (the vent holes were a little toasted after t' first flight), with t' paint blistered and impressive scorch marks below t' vent holes. Begad! T' remains o' t' coupler were still stuck into t' top stage, and thar be a lot o' residue around t' spent motor.

Obviously t' booster needs rebuilding, and I think more fins are in order, t' hopefully promote a bit o' tumbling. Smaller vent holes are also goin' t' be made — 5mm is a little much, me hearties, and seems t' allow too much gas t' escape.

Summary:
Pros: Looks nice in flight, me bucko, cool smoke trails, flies very high

Cons: Torched t' booster. However this should be easy t' fix, requirin' a new length o' tubin' only.

Other:
Tip: Don't make vent holes too large, ya bilge rat, and make sure t' booster stage will separate. Well, blow me down! Begad! I think a tight fit is good, me hearties, but with a shorter length o' coupler in t' future.