Flight Log for 2 November 1997, Monroe, WA

1500' to 2000' ceiling, wind 0-2 S increasing to 0-5 variable after noon.
Model Flt 
#
Recovery Type Motor Comments
Bertha 24
21
12" plastic parasheet w/ spill and vents Estes D12-7 This was the usual perfect flight for the Bertha -- there's never been, and likely will never be a more reliable model.  Unfortunately, on recovery, I noticed a crack in the fillet on one fin root -- these fillets are Elmer's Fill 'n Finish over white glue structural fillets -- and on careful inspection, found five more cracks out of eight fillets.  This isn't a huge problem, but requires that I wick some thin CA glue into each fillet to reinforce it before flying again.
Spike
4
18" nylon parasheet Estes D12-3 The packaging states that the Spike can be flown on D through H motors -- and I wanted to try out the lower end of that power range.  I found that the claims are true; you can get a safe flight on a Spike with a D12 motor, providing you didn't use too much epoxy in construction.  In my case, I used only yellow glue, and the 3rd centering ring I added was a fiber stuffing ring; as a result, my Spike is on the light side despite the one ounce penalty for the Universal Motor Retention System.  The altitude was low, but that's to be expected with a 12+ oz. rocket on a D12 . . . and there was certainly no problem with recovery.
Spike
5
18" nylon parasheet Econojet F20-7 This was the second motor from the same pack as the one that gave such good results in Kent on 11 October; unfortunately, this one must have been less carefully made; the forward bulkhead blew out of the casing, taking the burning delay element and intact ejection charge with it.  The good news is, in western Washington this time of year, you couldn't start a grass fire with thermite; the further good news is that the nose cone and recovery system simply got out of the way without damage; the final good news is that the propellant extinguished from the sudden pressure drop.  The rocket body never left the pad, though the nose cone implanted itself in the soft ground after springing back from the end of the shock cord.  Net damage: none.  I'm in negotiations with Aertoech right now concerning warranty service.
Spike
6
18" nylon parashheet Aerotech E18-4 (RMS 24/40) This flight went much better than the last; the igniter lit on the first try, the motor fired immediately, and the burn profile and delay were nominal .  I think I'll wind up burning a lot of these reloads in this rocket; it makes for a very pleasant flight, for less cost than an Estes D12.  I may also look around for some of the D15 load for this case; the extra 3 Ns (compared to the Estes tested value) couldn't hurt, and a little more thrust would be welcome; plus, these loads are even cheaper than the E18s.


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