Following some less than thrilling flights on the flying field with my old stock of Rapier L-2 motors, I put a number of these (both 'standard' and L-2 LT) on the test rig to see what they were actually putting out. This was interesting, enlightening and disappointing at the same time!
A significant proportion of these 2017 motors failed to ignite at all, despite extensive boring out and the use of a red hot igniter. Some that did ignite produced well below 100 mN with a fine confetti of white particles.
This inadequate thrust would explain the lack of my Draken's usually reliable climb out and flights which consisted of little more than extended glide into the ground.
Only a few motors ignited instantly, giving 105-110 mN. This explain's the Drakens occasional good flights.
This unpredictability is of course frustrating on the flying field and not at all fun and I can no longer sell these motors with a clear conscience. I have therefore disposed of
all my old (and quite large) stock of Rapiers.
So, Rapiers are dead. Long live TSP!
Talking to rocketeers who have 'kept the faith', it would appear the L-2 motors they most relish at the moment are '200 mN'. Hmmm ...The bad news is I had only a few '200 mN' motors and plenty of '320 mN' motors.
Tthe good news is that drilling out the nozzles of 320 mN motors to 1.8 mm resulted in a predictable and reliable thrust of 200-220 mN for 18- 20 sec.
It was easy enough, then, to produce a number of packs of '200 mN' thrust motors. Just to be sure, I did test a statistically significant sample of modified motors from these packs and was pleased that my earlier findings held up.
Bottom line: Please contact me if you would like some packs of these (pre-CE) TSP motors which are tested of proven performance.
Hurry, Hurry whilst stocks last!
Prices are £20 (GBP) for a pack of ten plus postage (if not collected in person at, say, a swapmeet).
In conlusion, I (and Daniel) have been using the TSP motors on the flying field all season and had a lot of fun. The CE TSP L-1 motors in particular are great:
Above: my TSP Gripen with a (CE) TSP L-1 motor. Nice.
The CE TSP L-2 motors (170 mN) too, are reliable and great for vintage 'Jetex 50' models. As are the CE TSP L-2HP motors (nominally 320 mN thrust) drilled out to 2mm.
CE TSP motors are of course still available from VMC and I for one am happy with these.